The invention relates to covalent polymer networks composed of macro-diacrylates and polyacrylates having shape memory properties and that can be used in medical technology.

1. Field of the Invention
The invention relates to macro-diacrylates and polyacrylates for the production of a covalent polymer network with shape memory properties, the polymer networks obtainable thereof and their use.
2. Description of the Related Art
Shape memory materials are materials which change their external shape when affected by an external stimulus. The materials are by way of example capable of changing their shape in a controlled manner when the temperature increases above what is known as the switching temperature Ttrans.
The shape memory effect is not a specific intrinsic property of materials (shape memory polymers ("SMPs")). Rather, it results directly from the combination of structure and morphology and from processing/programming technology.
In shape memory materials, a distinction is made between a permanent and a temporary shape. The material is first brought to its permanent shape by conventional processing methods (e.g., extrusion or injection molding). The material is then brought to its desired temporary shape and fixed. This procedure is also termed programming. It consists either in heating the specimen, forming, and a cooling procedure, or else in forming at relatively low temperature. The permanent shape is in memory, while the temporary shape is actually present. Heating of the material to a temperature higher than the transition temperature for a change of morphology (switching temperature) triggers the shape memory effect and thus leads to resumption of the permanent shape from memory.
The shape memory effect, i.e., permitting controlled shape alteration of a material via application of an external stimulus, is described, for example, in Angew. Chem., 114, 2138-62 (2002).
The shape memory polymer is first brought to its permanent shape by a conventional processing method. It is then deformed to the desired temporary shape and fixed in that shape (e.g., via temperature reduction). Heating to temperatures above the switching temperature triggers the shape memory effect, and the permanent shape is resumed from memory. The permanent shape can have been stabilized via physical crosslinking or via chemical crosslinking, in particular via covalent crosslinking. The covalent polymer network can on the one hand be obtained via subsequent crosslinking of linear polymers or on the other hand via a polyreaction of difunctional monomers. In turn, the monomers can be low-molecular-weight monomers or can themselves be macromolecules (macro-monomers).
For the purposes of the invention, a macro-diacrylate is a macro-monomer having two acrylate groups and a macro-polyacrylate is a macro-monomer having at least two acrylate groups.
Covalent polymer networks with shape memory properties are mostly obtained via free-radical polymerization (e.g., of macro-diacrylates). Production of covalent polymer networks often encompasses the following three stages:
1. synthesis of macrodiols,
2. acrylation of the end groups; and
3. free-radical crosslinking of the acrylate groups.
These shape memory polymers have been known for a long time, as can be found in the published overview "Formgedächtnis-Polymere" [Shape-Memory Polymers] by A. Lendlein and S. Kelch, Angew. Chem., 114, 2138-62 (2002)), which describes, inter alia, biodegradable polymer networks with shape memory via polymerization of oligo(ε-caprolactone) dimethacrylate whose average molecular weight is in the range from 2,000 to 10,000 g/mol in the presence of from 11 to 90 percent by weight of n-butyl acrylate. To prepare the oligo(ε-caprolactone) dimethacrylate, oligo(ε-caprolactone)-diol is to be functionalized with polymerizable methacrylate end groups. The macro-diacrylate described includes no urethane groups.
DE 102 17 351 B3 describes interpenetrating networks that include (i) a covalently crosslinked polymer component and (ii) a polyester-urethane component. The polyester-urethane component is not covalently crosslinked, but physically crosslinked. It derives from a macrodiol based on pentadecalactone, if appropriate together with caprolactone or from p-dioxanone, preference being given here to block polymers. The macrodiol whose average molecular weight is from approximately 1,000 to approximately 20,000 g/mol is reacted with diisocyanates to give polyesterurethanes whose molecular weights are from approximately 100,000 to approximately 250,000 g/mol. The details of preparation of the polyesterurethane component are not described. However, it clearly includes no reactive group, in particular no acrylate group.
The covalently crosslinked polymer component is obtained via crosslinking of functionalized macro-monomers. The functionalization is achieved via ethylenically unsaturated units, in particular via acrylate groups and methacrylate groups. The macro-monomers are homo- and/or copolyester diols based on caprolactone, lactide, glycolide and p-dioxanone. The hydroxyl groups are functionalized via syntheses known per se to give acrylate groups and methacrylate groups. By way of example, dimethacrylate polycaprolactone whose average molecular weight from GPC analysis is from 2,000 to 30,000 g/mol was obtained. DE 102 17 351 B3 includes no specific statements concerning preparation of the macro-diacrylates, though they include absolutely no urethane groups.
DE 699 17 224 T2 likewise describes biodegradable polymer compositions with shape memory characteristics, where the polymer includes either hard and soft segments (variant 1) or one or more soft segments which have been covalently or ionically crosslinked with one another (variant 2) or polymer mixtures (variant 3).
A copolyesterurethane is stated as an example of the polymer composition having hard and soft segments. This multiblock copolymer was prepared via reaction of a diisocyanate (e.g., of TMDI) in 1,2-dichloroethane at 80° C. in at least ten days with two different macrodiols via precipitation in hexane, and purified via repeated dissolution in 1,2-dichloroethane and precipitation in hexane. The macrodiols were a poly(6-caprolactone)-diol (i.e., the soft segment) and a α,ω-dihydroxy[oligo(L-lactate-co-glycolate)ethylene-oligo(L-lactate-co-glycolate)] (i.e., the hard segment). Although nothing is said about the end groups, the polyesterurethane includes no reactive groups, such as acrylate groups. As an example of covalent crosslinking, the synthesis of the macro-monomer from a polydiol and methacryloyl chloride is described. For this reaction, the following detailed steps in a process are needed:    (i) Methacryloyl chloride is added dropwise at 0° C. to a solution of poly (ε-caprolactone)-diol and triethylamin in tetrahydrofuran (THF);    (ii) The reaction mixture was stirred at 0° C. for three days, and the precipitated salt was filtered off;    (iii) Once the mixture had been concentrated at room temperature under reduced pressure, ethyl acetate is added and the mixture is again filtered;    (iv) Finally, the product was precipitated with a ten-fold excess of a mixture of n-hexane, diethyl ether and methanol;    (v) The colorless precipitate was collected, dissolved in dichloroethane and again precipitated; and    (vi) Finally, the poly(ε-caprolactone) dimethacrylate was carefully dried at room temperature under reduced pressure.
That process gives macro-monomers whose average molecular weights are from 4,500 to 10,000 g/mol. That type of preparation process for a macro-diacrylate is very complicated in terms of time (more than three days) and environmental factors (many purification steps with large amounts of solvents). The resultant macro-diacrylate clearly comprises absolutely no urethane groups. The obtained polymer mixture (variant 3) is mixture of thermoplastic polymers with the same basis structure. Nothing is said about reactive groups, and certainly nothing about acrylate groups.
DE 102 17 351 B3 describes polyesterurethanes which can exhibit shape memory effects. The macrodiol derived from polypentadecalactone whose average molecular weight is from 1,000 to 20,000 g/mol is reacted with conventional diisocyanates, preferably with trimethylhexane 1,6-diisocyanate (TMDI) to give corresponding polyesterurethanes whose molecular weight is in the range from 50,000 to 250,000 g/mol. The reaction takes place at 80° C. with stannous ethylhexanoate used as catalyst and 1,2-dichloroethane as solvent in an average of two days. Although nothing is said about the end groups, these are unreactive end groups and, in particular, not acrylate groups.
DE 692 21 128 T3 describes a mixture of isocyanate-terminated polyurethanes (polyurethane prepolymer). This reaction product is derived from an amorphous polyester polyol and from a polyisocyanate, in particular a diisocyanate. It is used together with a semicrystalline polyurethane derived from a polyester diol and a polyisocyanate, and with a prepolymer derived from a poly(tetramethylene ether) glycol and a polyisocyanate. This polymer mixture features good adhesion on metal substrates and polymer substrates and is therefore intended to be used as a hot-melt adhesive, as a coating and/or as a sealant. This polymer mixture is intended inter alia for use in adhesive bonding of polysubstrates because it has improved creep strength. Its use as an actual shape memory polymer is not described. The isocyanate prepolymers include no acrylate groups.
In view of the foregoing, the object of the invention includes providing novel covalent networks whose monomers can, with a view to both technical and economic factors, be rapidly prepared and easily purified. The intention is that the switching temperatures, the mechanical properties, and the degradation behavior of such networks be capable of controlled adjustment via variation of the composition, without resultant loss of the shape memory properties. If possible, the covalent polymer network should also be biodegradable.
Novel macro-diacrylates and polyacrylates usable for the production of covalent polymer networks with shape memory properties have been found, and are characterized in that they include both carboxylic ester structural units and urethane structural units.
The macro-polyacrylates of the invention include at least approximately 2 acrylate groups, preferably approximately 2, 3, 4, 5, 6, 7, 8, 9 or 10 and more preferably approximately 2, 3 or 4 acrylate groups.
For the purposes of the invention, preferred macro-diacrylates and preferred macro-polyacrylates that include macro-diacrylates have the general Formula (I):
in which R1 is a substituent of a macrodiol, R2 is at least one of a substituent of a low-molecular-weight diisocyanate or of a diisocyanate prepolymer with a number-average molecular weight Mn in the range from approximately 500 to approximately 3,000 g/mol, R3 is at least one of a hydrogen or a lower alkyl, R4 is at least one of a branched or unbranched alkylene group having from approximately 2 to approximately 10 carbon atoms and m is 0 or an integer in the range from approximately 1 to approximately 10.
For the purposes of the invention, preference is also given to macro-polyacrylates of the following general Formula (II):
and in particular to macro-diacrylates of the following general Formula (IIa):
in which R1 is a substituent of a macro-polyol, R3 is at least one of a hydrogen or lower alkyl, R5 is at least one of a branched or unbranched alkylene group having from approximately 2 to approximately 10 carbon atoms, and n is 2 or an integer greater than 2.
As macro-diols and polyols, polyester diols and polyols, polyether diols and polyols or polycarbonate diols and polyols are preferred. The macro-diols and polyols of the invention include at least approximately two hydroxy groups, preferably approximately 2, 3, 4, 5, 6, 7, 8, 9 or 10 and more preferably approximately 2, 3 or 4 hydroxy groups. As an example, macro-polyols with 2 hydroxy groups are also called macrodiols, such with 3 hydroxy groups macrotriols, such with 4 hydroxy groups macrotetroles, etc.
The preferred polyester diols and polyols are prepared by ring opening polymerization of cyclic lactones usually using an initiating compound or by polycondensation of polycarboxylic acid, polyhydroxycarboxylic acid, hydroxy polycarboxylic acid, or polyhydroxy polycarboxylic acid and polyhydroxy compound. In the case of polyhydroxycarboxylic acid, hydroxy polycarboxylic acid, or polyhydroxy polycarboxylic acid the polycondensation can also be performed between molecules of the same structure and/or the polycarboxylic acid and/or the polyhydroxy compound.
The functionality (valency) of the initiating compound, polycarboxylic acid, hydroxy polycarboxylic acid, polyhydroxy polycarboxylic acid, polyhydroxy carboxylic acid and polyhydroxy compound is selected by considerations that are obvious to a person skilled in the art to get the desired polyester polyol, e.g. polyester diol, triol, tetrol, etc.
As cyclic lactones for the ring opening polymerization ε-caprolactone, diglycolide, dilactide (LL-, DL-, LL/DL- or rac-dilactide), p-dioxanone, ω-pentadecanolactone, butyrolactone (β, γ-butyrolactone) or their mixtures are used. Preferred are ε-caprolactone, diglycolide, dilactide (LL-, DL-, LL/DL- or rac-dilactide) or their mixtures.
The polyester diols which are synthesized by polycondensation have an average hydroxyl functionality of at least about 1.9, are well known to the art and are prepared conventionally using an excess of the diol to provide hydroxyl termination. The other polyester polyols useful for the present invention can be prepared accordingly by known means.
Examples of the polycarboxylic acid, dicarboxylic acids, but also carboxylic acids of higher functionality (valency; e.g., tricarboxylic acids, tetracarboxylic acids, etc.), and the ester-forming derivatives or anhydride or mixtures of any two or more of these acids thereof include succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, pimelic acid, suberic acid, dodecanedicarboxylic acid, terephthalic acid, isophthalic acid, orthophthalic acid, phthalic acid, p-hydroxybenzoic acid, 1,2,3-propane tricarboxylic acid, and benzene -1,2,3-tricarboxylic acid (hemimellitic acid).
Examples for polyhydroxycarboxylic acid, hydroxy polycarboxylic acid and polyhydroxy polycarboxylic acid compounds that can be used for the invention include 3,4,5-trihydroxy benzoic acid (gallic acid), 2-hydroxy-nonadecan-1,2,3-tricarboxylic acid (agaricin acid), citric acid, hydroxy succinic acid, and dihydroxy succinic acid.
Examples of the polyhydroxy compound (i.e., polyols like diols, triols, tetrols, pentols, hexols, etc.), include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, 2-methyl-1,5-pentanediol, neopentyl glycol, 1,4-cyclohexanedimethanol, polycarbonate diol, bisphenol-A-ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polytetramethyleneoxide glycol, dimethylolpropionic acid, glycerine, 1,1,1-tris(hydroxymethyl)ethane (trimethylol ethane), 1,1,1-tris(hydroxymethyl) propane (trimethylol propane), [2,2-bis(hydroxymethyl)-1,3-propandiol (pentaerythrite, pentaerythritol), sugars (polyhydroxy aldehydes or polyhydroxy ketones) or sugar alcohols (reduced sugars), as well as ethoxylated derivatives of the polyols.
Examples of an initiating compound for the above described ring opening polymerization (i.e., a polyhydroxy compound, such as those mentioned above, but also other initiators that are known in the art) include polyamines or polymercaptanes or compounds which include a total of at least two groups selected from hydroxy, amino and mercapto groups.
Preferred polyester polyols and diols include: polycaprolactone polyol, poly -(ε-caprolactone-co-glycolide)-polyol, poly-(ε-caprolactone-co-lactide)-polyol, poly-(lactide-co-glycolide)-polyol, polypentadecalactone polyol, poly-(ε-caprolactone-co-pentadecalactone)-polyol, poly-(1,6-hexamethylene-adipate) polyol, poly-(1,6-hexamethylene-sebacate)-polyol, poly-(1,10-decamethylene-sebacate)-polyol, polycaprolactone diol, poly-(ε-caprolactone-co-glycolide)-diol, poly-(ε-caprolactone-co-lactide)-diol, poly-(lactide-co-glycolide)-diol, polypentadecalactone diol, poly-(ε-caprolactone-co-pentadecalactone)-diol, poly-(1,6-hexamethylene-adipate) diol, poly-(1,6-hexamethylene-sebacate)-diol, poly-(1,10-decamethylene-sebacate)-diol and the respectice triols, tetrols, pentols, hexols, etc.
Examples of the macrodiols include polyether diols such as polyoxyethylene glycol, polyoxypropylene glycol and polyoxytetramethylene glycol.
Examples of the macrodiols include polycarbonate diols such as a commercially available aliphatic polycarbonate ether diol (Desmophen® C2200) and length extended aliphatic polycarbonate ether diol with polycarboxylic acid or derivatives with diisocyanate.
Examples of the macro-polyols, in particular the macrodiols, include polyether ester block copolymers such as poly-(caprolactone-b-ethylene glycol-b-caprolactone) triblock copolymer, poly-(ω-pentadecanolactone-b-ethylene glycol-b-ω-pentadecanolactone) triblock copolymer, poly-(ll-lactide-b-ethylene glycol-b-ll-lactide) triblock copolymer, poly-(dl-Lactide-b-ethylene glycol-b-dl-lactide) triblock copolymer, poly-(caprolactone-b-pentadecalactone-b-caprolactone) triblock copolymer, poly-(propylene glycol-b-ethylene glycol-b-propylene glycol) triblock copolymer.
The preferred macro-diold and polyols, in particular the macrodiols, have an average molecular weight ranging from about 1,000 to 50,000 and more preferably from about 3,000 to 30,000 and most preferably 5,000 to 20,000, melting points within the range of about 20° C. to about 150° C., and more preferably within the range of about 30° C. to about 100° C., a hydroxyl functionality of 2 and acid number below 3 mg KOH/gram.
The urethane acrylate end groups, as for example the preferred CH2═CR3—CO—O—R4—O—CO—NH—R2—NH—CO— end groups, have been obtained in the first step via an addition reaction of an OH group of a macrodiol to an isocyanate group of a diisocyanate and in the second step of the process via an addition reaction of an OH group of a hydroxylated acrylate compound, preferably a hydroxyalkyl (meth)acrylate, to the other isocyanate group.
In the simplest case, the macro-diols and polyols, in particular the macrodiol, can be composed of a homo- or copolymer or block copolymer. The macropolyol can comprise urethane groups or comprise no urethane groups. In this case, it is thus possible with a single component to program a system with two temporary shapes, as described in DE 102 17 351 B3 for a polymer mixture.
Lower alkyl (R3) is generally a straight-chain or branched hydrocarbon substituent having from approximately 1 to approximately 4 carbon atoms.
The hydroxylated acrylate compound in the invention (see, e.g., the compound of Formula (VI) in the following) may preferably be a hydroxyalkyl acrylate wherein the carbon number of the alkyl group moiety is from approximately 1 to approximately 10, particularly preferably is a hydroxyalkyl acrylate wherein the carbon number of the alkyl group moiety is from approximately 1 to approximately 5. Particularly preferred among them is a hydroxyalkyl (meth)acrylate. Specifically, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, pentandiol mono(meth)acrylate or hexanediol mono(meth)acrylate may, for example, be mentioned, and 2-hydroxyethyl (meth)acrylate or 2-hydroxypropyl (meth)acrylate are particularly preferred. 2-Hydroxyethyl acrylate or 2-hydroxypropyl acrylate are most preferred.
As (mono) isocyanato acrylate compounds (see, e.g., the compound of Formula (VIII)) in principle are useful for the invention, and are formally (meant in the sense of chemical structure, not necessarily in the sense of chemical synthesis) derived from the hydroxylated acrylate compound described above by replacing the hydroxy group with an isocyanato group. Preferred compounds include isocyanatoalkyl acrylates, wherein the carbon number of the alkyl group moiety is from approximately 1 to approximately 10, and particularly preferably from approximately 1 to approximately 5. Particularly preferred among them are isocyanatoalkyl (meth)acrylates. Specifically, 2-isocyanatoethyl (meth)acrylate, 2-isocyanatopropyl (meth)acrylate, 3-isocyanatopropyl (meth)acrylate, 2-isocyanatobutyl (meth)acrylate or 4-isocyanatobutyl (meth)acrylate may, for example, be mentioned, and 2-isocyanatoethyl acrylate or 2-isocyanatopropyl acrylate are particularly preferred. 2-Isocyanatoethyl (meth)acrylate or 2-isocyanatopropyl (meth)acrylate are most preferred.
The hydroxylated acrylate compounds or the isocyanato acrylate compounds usually include only one acrylate group, but can also include 2 or more acrylate groups. The isocyanato acrylate compound can preferably be 1,1-bis(acryloyloxymethyl)ethyl isocyanate, a compound that is available from Showa Denko under the tradename KarenzBEI.
As polyisocyanate, in particular as diisocyanate (see, e.g., the compound of Formula (IV) in the following), trimethylhexamethylene diisocyanate, tolylene diisocyanate, isophorone diisocyanate and lysine diisocyanate, tolylene diisocyanate, 4,4′-diphenylmethane diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate, 4,4′-methylenebis(cyclohexylisocyanate), methylcyclohexane2,4-diisocyanate, methylcyclohexane-2,6-diisocyanate, 1,3-(isocyanate-methyl)cyclohexane, and isophorone diisocyanate are preferred. The polyisocyanate compounds may be used alone or in combination as a mixture of two or more of them.
For medical applications, polyisocyanates such as trimethylhexamethylene diisocyanate, tolylene diisocyanate, isophorone diisocyanate and lysine diisocyanate are most preferred.
It is also possible to use diisocyanate prepolymers whose molecular weight is greater than 500 g/mol, and in particular up to 3,000 g/mol. These polyurethane prepolymers are prepared via a known reactions of the abovementioned diisocyanates with low-molecular-weight diols or macrodiols (e.g., with oligoether diols, oligoester diols or oligocarbonate diols with MW of from 500 to 3,000 g/mol).
The preferred macro-polyol urethane acrylates, in particular the macrodiol urethane acrylates, will preferably have an average molecular weight ranging from approximately 1,000 to approximately 50,000 and more preferably from approximately 3,000 to approximately 30,000 and most preferably from approximately 5,000 to approximately 20,000, melting points within the range of approximately 20° to approximately 150° C. and more preferably within the range of approximately 30° to approximately 100° C., and an isocyanate content below approximately 5 ppm.
The first aspect of the invention provides two methods or processes for producing urethane polyacrylates as precursors for shape memory cross-linked polymers.
The first method includes reacting of the above-mentioned macrodiol with the polyisocyanate to form the isocyanate end terminated macrodiol and afterwards the end termination of the isocyanate end groups with the hydroxylated acrylate compound. By this method, a compound of general Formula (I) is obtained. In this method, the use of macropolyols with more than 2 hydroxy groups would result in undesired crosslinking in the first step.
The second method includes the end termination of the macropolyol in one step with the isocyanate group of the acrylate. By this method a compound of general Formula (II) is obtained.
The second aspect of the invention includes the curing of the macro-polyacrylate, preferably via photo-curing.
The third aspect of the invention includes the thermal and mechanical properties and the shape memory effect of these cross-linked urethane acrylates.
By the first method, a macrodiol, in particular the macrodiol (III),H—O—R1—OH  (III)and a polyisocyanate compound, in particular the polyisocyanate compound (IV),OCN—R2—NCO  (IV)are reacted under such a condition that the isocyanate group is stoichiometrically excessive in order to obtain an urethane prepolymer having a terminal isocyanate group, in particular prepolymer (V)OCN—R2—NH—CO[—O—R1—O—CO—NH—R2—NH—CO]m—O—R1—O—CO—NH—R2—NCO  (V),For each of (III), (IV) and (V), R1 and R2 are as defined above for general Formula (I). Then, the hydroxylated acrylate compound, in particular the hydroxylated (meth)acrylate compound (VI),CH2═CR3—CO—O—R4—OH  (VI)is reacted to the terminal isocyanate groups of the urethane prepolymer to give a polyester polyurethane diacrylate, in particular the polyester polyurethane diacrylate of the general Formula (I). In (VI), R3 and R4 are as defined above for general formula (I).
The proportions of the macrodiol component (e.g., the compound of general formula (III)) and the polyisocyanate compound (e.g., the compound of general formula (IV)) is preferably from approximately 1.5:1 to approximately 2:1.
The reaction is preferably carried out at a temperature for a common urethane-modification reaction (e.g., from approximately 30° to approximately 90° C. in solvent and from approximately 100° to approximately 150° C. solvent-free in melt). At the time of the reaction, a urethane-modification catalyst such as zinc naphthenate, dibutyltin dilaurate, tin 2-ethylhexanoate, triethylamine or 1,4-diazabicyclo[2.2.2]octane, may be used. But the reaction is preferably carried out without catalyst.
The reaction of the urethane prepolymer having a terminal isocyanate group with a hydroxylated acrylate compound, in particular the hydroxylated (meth)acrylate compound (VI), is carried out preferably in such a proportion that the molar ratio of the terminal isocyanate group to the hydroxyl group will preferably be from approximately 1:1 to approximately 1:1.5. The temperature for the reaction is preferably from approximately 30° to approximately 90° C. in solvent and from approximately 100° to approximately 150° C. solvent-free in melt. At the time of the reaction, a polymerization inhibitor may be added in order to control the thermal polymerization reaction of the acryloyl group, in particular the (meth)acryloyl group. As a preferred polymerization inhibitor, hydroquinone or hydroquinone monomethyl ether, may, for example, be mentioned. Such a polymerization inhibitor is used within a range of from approximately 100 to approximately 1000 ppm relative to the hydroxylated acrylate compound, in particular the hydroxylated (meth)acrylate compound (VI).
By the second method, a macro-polyol, preferably the macro-polyol of general Formula (VII),R1(OH)n  (VII)in particular the macrodiol (VIIa),R1(OH)2  (VIIa)and an isocyanato acrylate compound, in particular the isocyanato acrylate compound (VIII),CH2═CR3—CO—O—R5—NCO  (VIII)are reacted in an one step process to give a macro-polyacrylate, in particular the macro-polyacrylate of the general formula (II) or (IIa) respectively. The proportions of the macrodiol or polyol component, in particular the macropolyol component (VII) or (VIIa), and the isocyanato acrylate compound, in particular the isocyanato acrylate compound (VIII), preferably is n: 1. In the formulae, R1, R3, R5 and n have the same meaning as defined above for general Formula (II).
The reaction is preferably carried out at a temperature for a common urethane-modification reaction (i.e., from approximately 30° to approximately 90° C. in solvent and from approximately 100° to approximately 150° C. solvent-free in melt). At the time of the reaction, a urethane-modification catalyst such as zinc naphthenate, dibutyltin dilaurate, tin 2-ethylhexanoate, triethylamine or 1,4-diazabicyclo[2.2.2]octane, may be used. The reaction is preferably carried out, however, without catalyst. Preferred polymerization inhibitors include hydroquinone or hydroquinone monomethyl ether. Such a polymerization inhibitor is used within a range of from approximately 100 to approximately 1,000 ppm to the isocyanato acrylate compound.
The following advantages are associated with the preparation process of the invention for the macro-polyacrylate, in particular the macro-diacrylate:    1. The macro-diacrylates and polyacrylates are obtained more quickly and at lower cost;    2. It is easier to purify (less solvent);    3. The yield is higher;    4. Higher degrees of acrylation are achieved; and    5. The process (i.e., a one-pot reaction) makes it easier to increase the molecular weight of the macrodiol via reaction with the diisocyanate, and then to terminate it with diacrylate. Various macropolyols can be used together in the processes of the invention. Various switching segments can also therefore be introduced into the shape memory polymer.
The resultant covalent polymeric networks exhibit, among other things, good mechanical and thermal properties, a high degree of cross linking, good shape memory properties, a very low level of relaxation and creep effects and are biocompatible.
The cross-linking of the urethane diacrylates and polyacrylates, in particular the urethane diacrylates, take place by free-radically polymerization. The free-radically polymerization can be initiated by using a conventional chemical initiator system, such as a peroxide or a combination of a peroxide and an amine. The urethane diacrylates and polyacrylates, in particular the urethane diacrylates, are preferably initiated by using a photoinitiator, optionally combined with a suitable photosensitizer or accelerator. The photoinitiator should be capable of generating free radicals for addition polymerization at some wavelength between approximately 200 and approximately 800 nm, more preferred wavelength between approximately 250 and approximately 700 nm, most preferred wavelength between approximately 300 and approximately 500 nm. Suitable photoinitiators include, for example, alpha-diketones, monoketals of alpha-diketones or ketoaldehydes, acroleins and their corresponding ethers, chromophore-substituted halomethyl-s-triazines, chromophore-substituted halomethyl-oxadiazoles, aryliodonium salts, and other commercially available ultraviolet ("UV") and visible light photoinitiators. Preferred photoinitiator systems include, for example, a mono or diketone photoinitiator together with a suitable donor compound or accelerator. More preferred photoinitiators are Kip 150 (polyfunctional oligomeric hydroxy ketone, Lamberti Sp. A.), 1-hydroxy-cyclohexyl-phenyl-ketone, TZT (Liquid Benzophenone derivative) and D,L-champor quinone.
As thermoinitiators organic peroxides, benzoyl peroxide, lauroyl peroxide, dialkyl peroxides such as dicumyl peroxide and di-tert-butyl peroxide, peroxydicarbonates such as diisopropyl peroxydicarbonate and bis(4-tert-butylcyclohexyl) peroxydicarbonate, alkyl peresters such as tert-butyl peroxyoctoate and tert-butyl peroxybenzoate, can be used. In particular, lauroyl peroxide is preferred. Furthermore, a different kind of radical generator, for example a radical-generating azo compound such as azobisisobutyronitrile, may be used in lieu of the peroxide.
The covalently cross-linked shape memory urethane diacrylates and polyacrylates, in particular urethane diacrylates, can be semi-crystalline or amorphous and have generally switching temperatures within the range of approximately 20° to approximately 150° C. and more preferably within the range of approximately 20° to approximately 100° C. For medical application switching temperatures within the range of approximately 35° to approximately 55° are most preferred.
Due to the good thermal and mechanical properties, high shape recovery and good biocompatibility of the cross-linked urethane polyacrylate, in particular diacrylate, these materials can be used in many technical applications, preferred is the use as network precursors in medical technology.
The various embodiments of the invention having thus been generally described, several examples will hereafter be discussed to illustrate the inventive aspects more fully.
It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention and specific examples provided herein without departing from the spirit or scope of the invention. Thus, it is intended that the present invention covers the modifications and variations of this invention that come within the scope of any claims and their equivalents.

Helmholtz-Zentrum Geesthacht Zentrum Fuer Material- und Kuestenforschung GmbH


All purpose cleaning or microemulsion compositions more environmentally friendly, which is especially effective in the removal of oily or greasy soils, contains a positively charged surfactant-polymer complex, a hydrocarbon ingredient, a cosurfactant, and water.

The present invention relates to a hard surface cleaning composition containing a positively charged surfactant-polymer complex.
This invention relates to an improved all-purpose liquid cleaner designed in particular for cleaning hard surfaces and which is effective in removing grease soil and/or bath soil and in leaving unrinsed surfaces with a shiny appearance.
In recent years all-purpose liquid detergents have become widely accepted for cleaning hard surfaces, e.g., painted woodwork and panels, tiled walls, wash bowls, bathtubs, linoleum or tile floors, washable wall paper, etc. Such all-purpose liquids comprise clear and opaque aqueous mixtures of water-soluble synthetic organic detergents and water-soluble detergent builder salts. In order to achieve comparable cleaning efficiency with granular or powdered all-purpose cleaning compositions, use of water-soluble inorganic phosphate builder salts was favored in the prior art all-purpose liquids. For example, such early phosphate-containing compositions are described in U.S. Pat. Nos. 2,560,839; 3,234,138; 3,350,319; and British Patent No. 1,223,739.
In view of the environmentalist""s efforts to reduce phosphate levels in ground water, improved all-purpose liquids containing reduced concentrations of inorganic phosphate builder salts or non-phosphate builder salts have appeared. A particularly useful self-opacified liquid of the latter type is described in U.S. Pat. No. 4,244,840.
However, these prior art all-purpose liquid detergents containing detergent builder salts or other equivalent tend to leave films, spots or streaks on cleaned unrinsed surfaces, particularly shiny surfaces. Thus, such liquids require thorough rinsing of the cleaned surfaces which is a time-consuming chore for the user.
In order to overcome the foregoing disadvantage of the prior art all-purpose liquid, U.S. Pat. No. 4,017,409 teaches that a mixture of paraffin sulfonate and a reduced concentration of inorganic phosphate builder salt should be employed. However, such compositions are not completely acceptable from an environmental point of view based upon the phosphate content. On the other hand, another alternative to achieving phosphate-free all-purpose liquids has been to use a major proportion of a mixture of anionic and nonionic detergents with minor amounts of glycol ether solvent and organic amine as shown in U.S. Pat. No. 3,935,130. Again, this approach has not been completely satisfactory and the high levels of organic detergents necessary to achieve cleaning cause foaming which, in turn, leads to the need for thorough rinsing which has been found to be undesirable to today""s consumers.
Another approach to formulating hard surfaced or all-purpose liquid detergent composition where product homogeneity and clarity are important considerations involves the formation of oil-in-water (o/w) microemulsions which contain one or more surface-active detergent compounds, a water-immiscible solvent (typically a hydrocarbon solvent), water and a xe2x80x9ccosurfactantxe2x80x9d compound which provides product stability. By definition, an o/w microemulsion is a spontaneously forming colloidal dispersion of xe2x80x9coilxe2x80x9d phase particles having a particle size in the range of 25 to 800 xc3x85 in a continuous aqueous phase.
In view of the extremely fine particle size of the dispersed oil phase particles, microemulsions are transparent to light and are clear and usually highly stable against phase separation.
Patent disclosures relating to use of grease-removal solvents in o/w microemulsions include, for example, European Patent Applications EP 0137615 and EP 0137616xe2x80x94Herbots et al; European Patent Application EP 0160762xe2x80x94Johnston et al; and U.S. Pat. No. 4,561,991xe2x80x94Herbots et al. Each of these patent disclosures also teaches using at least 5% by weight of grease-removal solvent.
It also is known from British Patent Application GB 2144763A to Herbots et al, published Mar. 13, 1985, that magnesium salts enhance grease-removal performance of organic grease-removal solvents, such as the terpenes, in o/w microemulsion liquid detergent compositions. The compositions of this invention described by Herbots et al. require at least 5% of the mixture of grease-removal solvent and magnesium salt and preferably at least 5% of solvent (which may be a mixture of water-immiscible non-polar solvent with a sparingly soluble slightly polar solvent) and at least 0.1% magnesium salt.
However, since the amount of water immiscible and sparingly soluble components which can be present in an o/w microemulsion, with low total active ingredients without impairing the stability of the microemulsion is rather limited (for example, up to 18% by weight of the aqueous phase), the presence of such high quantities of grease-removal solvent tend to reduce the total amount of greasy or oily soils which can be taken up by and into the microemulsion without causing phase separation.
The following representative prior art patents also relate to liquid detergent cleaning compositions in the form of o/w microemulsions: U.S. Pat. No. 4,472,291xe2x80x94Rosario; U.S. Pat. No. 4,540,448xe2x80x94Gauteer et al; U.S. Pat. No. 3,723,330xe2x80x94Sheflin; etc.
Liquid detergent compositions which include terpenes, such as d-limonene, or other grease-removal solvent, although not disclosed to be in the form of o/w microemulsions, are the subject matter of the following representative patent documents: European Patent Application 0080749; British Patent Specification 1,603,047; 4,414,128; and 4,540,505. For example, U.S. Pat. No. 4,414,128 broadly discloses an aqueous liquid detergent composition characterized by, by weight:
(a) from 1% to 20% of a synthetic anionic, nonionic, amphoteric or zwitterionic surfactant or mixture thereof;
(b) from 0.5% to 10% of a mono- or sesquiterpene or mixture thereof, at a weight ratio of (a):(b) being in the range of 5:1 to 1:3; and
(c ) from 0.5% 10% of a polar solvent having a solubility in water at 15xc2x0 C. in the range of from 0.2% to 10%. Other ingredients present in the formulations disclosed in this patent include from 0.05% to 2% by weight of an alkali metal, ammonium or alkanolammonium soap of a C13-C24 fatty acid; a calcium sequestrant from 0.5% to 13% by weight; non-aqueous solvent, e.g., alcohols and glycol ethers, up to 10% by weight; and hydrotropes, e.g., urea, ethanolamines, salts of lower alkylaryl sulfonates, up to 10% by weight. All of the formulations shown in the Examples of this patent include relatively large amounts of detergent builder salts which are detrimental to surface shine.
A pH neutral microemulsion composition based on paraffin sulfonate and ethoxylated nonionic surfactant is able to deliver improved grease cleaning versus built, alkaline compositions. Besides the improved grease cleaning, this approach is much safer to surfaces as well as less aggressive on consumer""s hands (Loth et alxe2x80x94U.S. Pat. No. 5,075,026).
The microemulsion technology provides outstanding oil uptake capacity because of the adjustment of the curvature of the surfactant micelles by the molecules of the cosurfactant. Rod-like micelles are preferred as they can xe2x80x9cswallowxe2x80x9d oil to become globular without increasing the surface of contact between the hydrophobic core of the micelle and the hydrophilic continuous phase.
In diluted usage however, the microemulsion state is usually lost and the cleaning performance relies on the adsorption efficacy and leaving character of the surfactant system. Nonionic surfactants perform very well on grease, as they are excellent grease xe2x80x9csolubilizersxe2x80x9d. Actually, they spontaneously form swollen micelles. In moderate climate countries such as the northern states of the United States and the northern countries of Europe, the soil on the hard surfaces contains a major proportion of greasy materials. It is accordingly not surprising that the anionic-nonionic surfactant based microemulsion is very efficient in those countries. However, nonionic surfactants do not impart oil repelling properties and can not deliver soil antiattachment properties on treated hard surfaces so as to achieve next time easier cleaning of said treated surface.
The instant invention teaches hard surface cleaning containing a positively charged complex of an anionic surfactant which is an alkali metal salt such as sodium, of a fluoroalkyl sulfonate, or an ammonium salt of a fluoroalkyl sulfonate, or a mixture thereof, which exhibits very low surface tensions with a polycationic polymer that imparts oil repelling properties and delivers soil antiattachment properties on treated hard surfaces and delivers this desired property.
The present invention provides an improved, clear, liquid hard surface cleaning composition having improved interfacial tension which improves cleaning hard surfaces such as plastic, vitreous and metal surfaces having a shiny finish, oil stained floors, automative engines and other engines. More particularly, the improved cleaning compositions exhibit good grease soil removal properties and leave the cleaned surfaces shiny without the need of or requiring only minimal additional rinsing or wiping. The latter characteristic is evidenced by little or no visible residues on the unrinsed cleaned surfaces and, accordingly, overcomes one of the disadvantages of prior art products. The instant compositions exhibit a grease release effect in that the instant compositions impede or decrease the anchoring of greasy soil on surfaces that have been cleaned with the instant compositions as compared to surfaces cleaned with a microemulsion composition which means that the grease soiled surface is easier to clean upon subsequent cleanings.
Surprisingly, these desirable results are accomplished even in the absence of polyphosphate or other inorganic or organic detergent builder salts and also in the complete absence or substantially complete absence of grease-removal solvent.
In one aspect, the invention generally provides a stable, clear all-purpose, hard surface cleaning composition especially effective in the removal of oily and greasy oil. The cleaning composition includes, on a weight basis:
about 0.1% to about 25%, more preferably about 0.2% to about 20% of a positively charged surfactant-polymer complex comprising at least one alkali metal salt of a fluoroalkyl sulfonate surfactant or at least one ammonium salt of a fluoroalkyl sulfonate surfactant and a polycationic polymer;
0.1% to about 25%, more preferably 1% to 20%, of at least one ethoxylated nonionic surfactant;
about 0 to about 50%, more preferably 1% to 20%, of a water-mixable cosurfactant having either limited ability or substantially no ability to dissolve oily or greasy soil;
0 to about 15%, more preferably 0.1% to 10% of a nonfluorinated anionic surfactant;
0 to about 15%, more preferably 0.1% to 10% of a zwitterionic surfactant;
0 to about 3.5% of a fatty acid;
0 to about 15% of magnesium sulfate heptahydrate;
about 0 to about 10.0% of a perfume or water insoluble hydrocarbon; and
the balance being water, said proportions being based upon the total weight of the composition.
The cleaning composition can be in the form of a microemulsion in which case the concentration of the water mixable cosurfactant is about 0 to about 50 wt. %, preferably about 1 wt. % to about 20 wt. % and the concentration of the perfume or water insoluble hydrocarbon is about 0.4 wt. % to about 10.0 wt. %. The dispersed oil phase of the o/w microemulsion is composed essentially of a water-immiscible or hardly water-soluble perfume. Quite surprisingly although the perfume is not, per se, a solvent for greasy or oily soil,xe2x80x94even though some perfumes may, in fact, contain as much as 80% of terpenes which are known as good grease solventsxe2x80x94the inventive compositions in dilute form have the capacity to solubilize up to 10 times or more of the weight of the perfume of oily and greasy soil, which is removed or loosened from the hard surface by virtue of the action of the anionic surfactant, said soil being taken up into the oil phase of the o/w microemulsion.
In second aspect, the invention generally provides highly concentrated microemulsion compositions in the form of either an oil-in-water (o/w) microemulsion or a water-in-oil (w/o) microemulsion which when diluted with additional water before use can form dilute o/w microemulsion compositions. Broadly, the concentrated microemulsion compositions contain, by weight, 0.1% to 25% of the positively charged surfactant-polymer complex, 0.1% to 25% of at least one ethoxylated nonionic surfactant, 0% to 2.5% of a fatty acid, 0.4% to 10% of perfume or water insoluble hydrocarbon having 6 to 18 carbon atoms, 0 to 50% of a cosurfactant, and the balance being water.
The present invention relates to a stable all purpose hard surface cleaning or microemulsion composition containing a surfactant-polymer complex for delivering soil antiattachment properties. The invention also relates to a light duty liquid composition or light duty liquid microemulsion composition. This present invention also useful in the formation of toilet bowl cleaners.
The present invention relates to a stable hard surface cleaning composition containing approximately by weight: 0.1% to 25% of a positively charged complex of an alkali metal salt of a fluoroalkyl sulfonate surfactant or an ammonium salt of a fluoroalkyl sulfonate surfactant or a mixture thereof and a polycationic polymer, 0.1% to 25% of at least one ethoxylated nonionic surfactant, 0 to 50% of a cosurfactant, 0 to 10% of a water insoluble hydrocarbon or a perfume, 0 to 15% of a nonfluorinated anionic surfactant, 0 to 15% of a zwitterionic surfactant, and the balance being water, wherein the cleaning composition can be in the form of a microemulsion in which case the concentration of the water mixable cosurfactant is about 0 to about 50.0 wt. %, preferably about 0.1 wt. % to about 50.0 wt. % and the concentration of the perfume or water insoluble hydrocarbon is about 0.4 wt. % to about 10.0 wt. %.
When mixing an alkali metal salt such as sodium of a fluorinated anionic surfactant, or an ammonium salt of a fluoroalkyl sulfonate surfactant, or mixtures thereof, and a polycationic polymer, attractive interactions are developed that are very strong and lead to the formation of anionic-cationic complexes in-situ. The complex interactions take place along the polymer backbone, so that surfactant-polymer complexes exist in solution. Attention must be paid not to complex all the positive charges on the polycationic polymer so as to still have enough electric charges on the whole structure so that the complex is positively charged so as to keep the complex water soluble (otherwise phase separation or precipitation might occur). The presence of positive charges on the surfactant-polymer system allows subsequent anchorage on substrate surface for modifying the surface energy.
One of the objects of the instant invention is to deliver higher proportions of a fluoroalkyl anionic surfactant in the adsorbed layer at the solid-water interface by means of surfactant-polymer mixtures. This is due to a boosted adsorption tendency as compare to fluoroalkyl anionic individual surfactant by means of neutralization between the negative charge of the anionic surfactant and the positive charge of the polycationic surfactant that is used in admixture with the anionic surfactant in the instant compositions and due to an increased hydrophobic character imparted to the polymer by the anionic surfactant linked to its backbone. Two anionic surfactants can be used in composition wherein one of the anionic surfactants will possibly preferentially associate with the polycationic surfactant through electrostatic interactions.
According to the present invention, the role of the hydrocarbon is provided by a non-water-soluble perfume. Typically, in aqueous based compositions the presence of a solubilizers, such as alkali metal lower alkyl aryl sulfonate hydrotrope, triethanolamine, urea, etc., is required for perfume dissolution, especially at perfume levels of 1% and higher, since perfumes are generally a mixture of fragrant essential oils and aromatic compounds which are generally not water-soluble. Therefore, by incorporating the perfume into the aqueous cleaning composition as the oil (hydrocarbon) phase of the ultimate o/w microemulsion composition, several different important advantages are achieved.
First, the cosmetic properties of the ultimate cleaning composition are improved: the compositions are both clear (as a consequence of the formation of a microemulsion) and highly fragranced (as a consequence of the perfume level).
Second, the need for use of solubilizers, which do not contribute to cleaning performance, is eliminated.
Third, an improved grease release effect and an improved grease removal capacity in neat (undiluted) usage of the dilute aspect or after dilution of the concentrate can be obtained without detergent builders or buffers or conventional grease removal solvents at neutral or acidic pH and at low levels of active ingredients while improved cleaning performance can also be achieved in diluted usage.
As used herein and in the appended claims the term xe2x80x9cperfumexe2x80x9d is used in its ordinary sense to refer to and include any non-water soluble fragrant substance or mixture of substances including natural (i.e., obtained by extraction of flower, herb, blossom or plant), artificial (i.e., mixture of natural oils or oil constituents) and synthetically produced substance) odoriferous substances. Typically, perfumes are complex mixtures of blends of various organic compounds such as alcohols, aldehydes, ethers, aromatic compounds and varying amounts of essential oils (e.g., terpenes) such as from 0% to 80%, usually from 10% to 70% by weight. The essential oils themselves are volatile odoriferous compounds and also serve to dissolve the other components of the perfume.
In the present invention the precise composition of the perfume is of no particular consequence to cleaning performance so long as it meets the criteria of water immiscibility and having a pleasing odor. Naturally, of course, especially for cleaning compositions intended for use in the home, the perfume, as well as all other ingredients, should be cosmetically acceptable, i.e., non-toxic, hypoallergenic, etc.
The hydrocarbon such as a perfume is present in the hard surface cleaning composition in an amount of from 0 to 10% by weight, preferably 0.4% to 10% by weight, more preferably from 0.4% to 3.0% by weight, especially preferably from 0.5% to 2.0% by weight. If the hydrocarbon (perfume) is added in amounts more than 10% by weight, the cost is increased without any additional cleaning benefit and, in fact, with some diminishing of cleaning performance insofar as the total amount of greasy or oily soil which can be taken up in the oil phase of the microemulsion will decrease proportionately.
Furthermore, although superior grease removal performance will be achieved for perfume compositions not containing any terpene solvents, it is apparently difficult for perfumers to formulate sufficiently inexpensive perfume compositions for products of this type (i.e., very cost sensitive consumer-type products) which includes less than 20%, usually less than 30%, of such terpene solvents.
Thus, merely as a practical matter, based on economic consideration, the microemulsion compositions of the present invention may often include as much as 0.2% to 7% by weight, based on the total composition, of terpene solvents introduced thereunto via the perfume component. However, even when the amount of terpene solvent in the cleaning formulation is less than 1.5% by weight, such as up to 0.6% by weight or 0.4% by weight or less, satisfactory grease removal and oil removal capacity is provided by the inventive diluted microemulsions.
In place of the perfume one can employ a water insoluble paraffin or isoparaffin having 6 to 18 carbon at a concentration of 0 to 8 wt. percent, preferably 0.4 to 8.0 wt. percent, more preferably 0.4 to 3.0 wt. %.
The positively charged complex contained in the instant compositions comprises a complex of:
(a) an alkali metal salt such as sodium of a fluoroalkyl sulfonate anionic surfactant or an ammonium salt of a fluoroalkyl sulfonate anionic surfactant or a mixture thereof; and
(b) a polycationic polymer, wherein the molar ratio of the anionic surfactant to the positively charged binding sites available on the polycationic polymer backbone is 0.95:1 to 0.05:1, more preferably 0.9:1 to 0.1:1. The instant composition contains about 0.1 to about 25 wt. %, more preferably about 0.2 to about 20 wt. % of the positively charged complex.
The fluoroalkyl sulfonate anionic surfactant which has a RF fluoroalkyl group which is a C16F33 to C5F11, preferably a C6F13 to C10F21, fluoroalkyl group and can be selected among the different compounds being depicted by the following structures of,
perfluoroalkane sulfonate salt:
RFxe2x80x94SO3xe2x88x92X+
or perfluoroalkylethane sulfonate salt:
or perfluoroalkyl group containing sulfonate with sulfide and carbonamide linkages:
wherein, X can be an alkali metal counterion such as sodium, or an ammonium counterion such as NH4+, and R1 and R2 are H or methyl groups.
The polycationic polymer is a polyacrylamide dialkyl dimethyl ammonium chloride copolymer having about 25 wt. % to 90 wt. % of the dialkyl dimethyl ammonium chloride monomer and is depicted by the structure of:
wherein m is about 5000 to about 60000.
Another useful polycationic polymer is a polyvinyl pyrrolidone/vinyl imidazole/quaternized vinyl-imidazole [40/40/20] terpolymer. The ratio of comonomers in the foregoing terpolymer is not particularly critical and can be modified to provide the desired soil antiattachment effect.
The at least one nonionic surfactant used in the instant cleaning composition is selected from the group of an aliphatic ethoxylated nonionic surfactant and an aliphatic ethoxylated/propoxylated nonionic surfactant and mixtures thereof.
The water soluble aliphatic ethoxylated nonionic surfactants utilized in this invention are commercially well known and include the primary aliphatic alcohol ethoxylates and secondary aliphatic alcohol ethoxylates. The length of the polyethenoxy chain can be adjusted to achieve the desired balance between the hydrophobic and hydrophilic elements.
The nonionic surfactant class includes the condensation products of a higher alcohol (e.g., an alkanol containing about 8 to 16 carbon atoms in a straight or branched chain configuration) condensed with about 4 to 20 moles of ethylene oxide, for example, lauryl or myristyl alcohol condensed with about 16 moles of ethylene oxide (EO), tridecanol condensed with about 6 to 15 moles of EO, myristyl alcohol condensed with about 10 moles of EO per mole of myristyl alcohol, the condensation product of EO with a cut of coconut fatty alcohol containing a mixture of fatty alcohols with alkyl chains varying from 10 to about 14 carbon atoms in length and wherein the condensate contains either about 6 moles of EO per mole of total alcohol or about 9 moles of EO per mole of alcohol and tallow alcohol ethoxylates containing 6 EO to 11 EO per mole of alcohol.
A preferred group of the foregoing nonionic surfactants are the Neodol ethoxylates (Shell Co.), which are higher aliphatic, primary alcohol containing about 9-15 carbon atoms, such as C9-C11 alkanol condensed with 4 to 10 moles of ethylene oxide (Neodol 91-8 or Neodol 91-5), C12-13 alkanol condensed with 6.5 moles ethylene oxide (Neodol 23-6.5), C12-15 alkanol condensed with 12 moles ethylene oxide (Neodol 25-12), C14-15 alkanol condensed with 13 moles ethylene oxide (Neodol 45-13), and the like. Such ethoxamers have an HLB (hydrophobic lipophilic balance) value of about 8 to 15 and give good O/W emulsification, whereas ethoxamers with HLB values below 7 contain less than 4 ethyleneoxide groups and tend to be poor emulsifiers and poor detergents.
Additional satisfactory water soluble alcohol ethylene oxide condensates are the condensation products of a secondary aliphatic alcohol containing 8 to 18 carbon atoms in a straight or branched chain configuration condensed with 5 to 30 moles of ethylene oxide. Examples of commercially available nonionic detergents of the foregoing type are C11-C15 secondary alkanol condensed with either 9 EO (Tergitol 15-S-9) or 12 EO (Tergitol 15-S-12) marketed by Union Carbide.
One of the water soluble nonionic surfactants which can be utilized in this invention are an aliphatic ethoxylated/propoxylated nonionic surfactants which are depicted by the formula:
wherein R is a branched chain alkyl group having about 10 to about 16 carbon atoms, preferably an isotridecyl group and x and y are independently numbered from 1 to 20. A preferred ethoxylated/propoxylated nonionic surfactant is Plurafac(copyright) 300 manufactured by BASF.
Suitable water-soluble non-soap, anionic surfactants which are nonfluorinated which are used in the instant compositions include those surface-active or detergent compounds which contain an organic hydrophobic group containing generally 8 to 26 carbon atoms and preferably 10 to 18 carbon atoms in their molecular structure and at least one water-solubilizing group selected from the group of sulfonate, sulfate and carboxylate so as to form a water-soluble detergent. Usually, the hydrophobic group will include or comprise a C8-C22 alkyl, alkyl or acyl group. Such surfactants are employed in the form of water-soluble salts and the salt-forming cation usually is selected from the group consisting of sodium, potassium, ammonium, magnesium and mono-, di- or tri-C2-C3 alkanolammonium, with the sodium, magnesium and ammonium cations again being preferred.
Examples of suitable sulfonated anionic surfactants are the well known higher alkyl mononuclear aromatic sulfonates such as the higher alkyl benzene sulfonates containing from 10 to 16 carbon atoms in the higher alkyl group in a straight or branched chain, C8-C15 alkyl toluene sulfonates and C8-C15 alkyl phenol sulfonates.
A preferred sulfonate is linear alkyl benzene sulfonate having a high content of 3- (or higher) phenyl isomers and a correspondingly low content (well below 50%) of 2- (or lower) phenyl isomers, that is, wherein the benzene ring is preferably attached in large part at the 3 or higher (for example, 4, 5, 6 or 7) position of the alkyl group and the content of the isomers in which the benzene ring is attached in the 2 or 1 position is correspondingly low.
Other suitable anionic surfactants are the olefin sulfonates, including long-chain alkene sulfonates, long-chain hydroxyalkane sulfonates or mixtures of alkene sulfonates and hydroxyalkane sulfonates. These olefin sulfonate detergents may be prepared in a known manner by the reaction of sulfur trioxide (SO3) with long-chain olefins containing 8 to 25, preferably 12 to 21 carbon atoms and having the formula RCHxe2x95x90CHR1 where R is a higher alkyl group of 6 to 23 carbons and R1 is an alkyl group of 1 to 17 carbons or hydrogen to form a mixture of sultones and alkene sulfonic acids which is then treated to convert the sultones to sulfonates. Preferred olefin sulfonates contain from 14 to 16 carbon atoms in the R alkyl group and are obtained by sulfonating an xcex1-olefin.
Other examples of suitable anionic sulfonate surfactants are the paraffin sulfonates containing 10 to 20, preferably 13 to 17, carbon atoms. Primary paraffin sulfonates are made by reacting long-chain alpha olefins and bisulfites and paraffin sulfonates having the sulfonate group distributed along the paraffin chain are shown in U.S. Pat. Nos. 2,503,280; 2,507,088; 3,260,744; 3,372,188; and German Patent 735,096.
Examples of satisfactory anionic sulfate surfactants are the C8-C18 alkyl sulfate salts the ethoxylated C8-C18 alkyl ether sulfate salts having the formula R(OC2H4)nOSO3M wherein n is 1 to 12, preferably 1 to 5, and M is a metal cation selected from the group consisting of sodium, potassium, ammonium, magnesium and mono-, di- and triethanol ammonium ions. The alkyl sulfates may be obtained by sulfating the alcohols obtained by reducing glycerides of coconut oil or tallow or mixtures thereof and neutralizing the resultant product.
On the other hand, the ethoxylated alkyl ether sulfates are obtained by sulfating the condensation product of ethylene oxide with a C8-C18 alkanol and neutralizing the resultant product. The alkyl sulfates may be obtained by sulfating the alcohols obtained by reducing glycerides of coconut oil or tallow or mixtures thereof and neutralizing the resultant product. The ethoxylated alkyl ether sulfates differ from one another in the number of moles of ethylene oxide reacted with one mole of alkanol. Preferred alkyl sulfates and preferred ethoxylated alkyl ether sulfates contain 10 to 16 carbon atoms in the alkyl group.
The ethoxylated C8-C12 alkylphenyl ether sulfates containing from 2 to 6 moles of ethylene oxide in the molecule also are suitable for use in the inventive compositions. These surfactants can be prepared by reacting an alkyl phenol with 2 to 6 moles of ethylene oxide and sulfating and neutralizing the resultant ethoxylated alkylphenol.
Other suitable anionic surfactants are the C9-C15 alkyl ether polyethenoxyl carboxylates having the structural formula R(OC2H4)nOXCOOH wherein n is a number from 4 to 12, preferably 5 to 10 and X is selected from the group consisting of
CH2, (C(O)R1 and

wherein R1 is a C1-C3 alkylene group. Preferred compounds include C9-C11 alkyl ether polyethenoxy (7-9) C(O)CH2CH2COOH, C13-C15 alkyl ether polyethenoxy (7-9)
and C10-C12 alkyl ether polyethenoxy (5-7) CH2COOH. These compounds may be prepared by condensing ethylene oxide with appropriate alkanol and reacting this reaction product with chloracetic acid to make the ether carboxylic acids as shown in U.S. Pat. No. 3,741,911 or with succinic anhydride or phthalic anhydride. Obviously, these anionic surfactants will be present either in acid form or salt form depending upon the pH of the final composition, with salt forming cation being the same as for the other anionic surfactants.
The zwitterionic surfactant which can be optionally used in the instant composition is a water soluble betaine having the general formula:
wherein Xxe2x88x92 is selected from the group consisting of SO3xe2x88x92 and CO2xe2x88x92 and R1 is an alkyl group having 10 to about 20 carbon atoms, preferably 12 to 16 carbon atoms, or the amido radical:
wherein R is an alkyl group having about 9 to 19 carbon atoms and a is the integer 1 to 4; R2 and R3 are each alkyl groups having 1 to 3 carbons and preferably 1 carbon; R4 is an alkylene or hydroxyalkylene group having from 1 to 4 carbon atoms and, optionally, one hydroxyl group. Typical alkyldimethyl betaines include decyl dimethyl betaine or 2-(N-decyl-N,N-dimethyl-ammonia)acetate, coco dimethyl betaine or 2-(N-coco N,N-dimethylammonia)acetate, myristyl dimethyl betaine, palmityl dimethyl betaine, lauryl dimethyl betaine, cetyl dimethyl betaine, stearyl dimethyl betaine, etc. The amidobetaines similarly include cocoamidoethylbetaine, cocoamidopropyl betaine and the like. Preferred betaines are coco (C8-C18) amidopropyl dimethyl betaine and lauryl dimethyl betaine.
A cosurfactant can be optionally used in forming the microemulsion composition. Three major classes of compounds have been found to provide highly suitable cosurfactants over temperature ranges extending from 5xc2x0 C. to 43xc2x0 C. for instance; (1) water-soluble C3-C4 alkanols, polyethylene glycols of the formula HO(CH2CH2O)nH wherein n is about 8 to about 14, polypropylene glycol of the formula HO(CH3CHCH2O)nH wherein n is a number from 2 to 18 and copolymers of ethylene oxide and propylene oxide and mono C1-C6 alkyl ethers and esters of ethylene glycol and propylene glycol having the structural formulas R(X)nOH and R1(X)nOH wherein R is C1-C6 alkyl, R1 is C2-C4 acyl group, X is (OCH2CH2) or (OCH2(CH3)CH) and n is a number from 1 to 4; (2) aliphatic mono- and di-carboxylic acids containing 2 to 10 carbon atoms, preferably 3 to 6 carbons in the molecule; and (3) triethyl phosphate. Additionally, mixtures of two or more of the three classes of cosurfactant compounds may be employed where specific pH""s are desired.
When the mono- and di-carboxylic acid (Class 2) cosurfactants are employed in the instant microemulsion compositions at a concentration of 2 to 10 wt. %, the microemulsion compositions can be used as a cleaners for bathtubs and other hard surfaced items, which are acid resistant thereby removing lime scale, soap scum and greasy soil from the surfaces of such items damaging such surfaces. If these surfaces are of zirconium white enamel, they can be damaged by these compositions.
An aminoalkylene phophoric acid at a concentration of 0.01 to 0.2 wt. % can be optionally used in conjunction with the mono- and di-carboxylic acids, wherein the aminoalkylene phosphoric acid helps prevent damage to zirconium white enamel surfaces. Additionally, 0.05 to 1% of phosphoric acid can be used in the composition.
Representative members of the polypropylene glycol include dipropylene glycol and polypropylene glycol having a molecular weight of 200 to 1000, e.g., polypropylene glycol 400. Other satisfactory glycol ethers are ethylene glycol monobutyl ether (butyl cellosolve), diethylene glycol monobutyl ether (butyl carbitol), propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, triethylene glycol monobutyl ether, mono, di, tri propylene glycol monobutyl ether, tetraethylene glycol monobutyl ether, triethylene glycol monohexyl ether, tetraethylene glycol monohexyl ether, pentaethylene glycol monohexyl ether, propylene glycol tertiary butyl ether, ethylene glycol monoacetate and dipropylene glycol propionate.
Representative members of the aliphatic carboxylic acids include C3-C6 alkyl and alkenyl monobasic acids such as acrylic acid and propionic acid and dibasic acids such as glutaric acid and mixtures of glutaric acid with adipic acid and succinic acid, as well as mixtures of the foregoing acids.
While all of the aforementioned glycol ether compounds and acid compounds provide the described stability, the most preferred cosurfactant compounds of each type, on the basis of cost and cosmetic appearance (particularly odor), are diethylene glycol monobutyl ether or pentaethylene glycol monohexyl ether and a mixture of adipic, glutaric and succinic acids, respectively. The ratio of acids in the foregoing mixture is not particularly critical and can be modified to provide the desired odor. Generally, to maximize water solubility of the acid mixture glutaric acid, the most water-soluble of these three saturated aliphatic dibasic acids, will be used as the major component.
Generally, weight ratios of adipic acid: glutaric acid:succinic acid is 1-3:1-8:1-5, preferably 1-2:1-6:1-3, such as 1:1:1, 1:2:1, 2:2:1, 1:2:1.5, 1:2:2, 2:3:2, etc. can be used with equally good results.
Still other classes of cosurfactant compounds providing stable microemulsion compositions at low and elevated temperatures are the mono-, di- and triethyl esters of phosphoric acid such as triethyl phosphate.
The amount of cosurfactant which might be required to stabilize the microemulsion compositions will, of course, depend on such factors as the surface tension characteristics of the cosurfactant, the type and amounts of the positively charged surfactant-polymer complex and perfumes, and the type and amounts of any other additional ingredients which may be present in the composition and which have an influence on the thermodynamic factors enumerated above. Generally, amounts of cosurfactant in the range of from 0 to 50 wt. %, preferably from 0.5 wt. % to 15 wt. %, especially preferably from 1 wt. % to 7 wt. %, provide stable microemulsions for the above-described levels of primary surfactants and perfume and any other additional ingredients as described below.
As will be appreciated by the practitioner, the pH of the final microemulsion will be dependent upon the identity of the cosurfactant compound, with the choice of the cosurfactant being effected by cost and cosmetic properties, particularly odor. For example, microemulsion compositions which have a pH in the range of 1 to 10 may employ either the class 1 or the class 4 cosurfactant as the sole cosurfactant, but the pH range is reduced to 1 to 8.5 when the polyvalent metal salt is present. On the other hand, the class 2 cosurfactant can only be used as the sole cosurfactant where the product pH is below 3.2. However, where the acidic cosurfactants are employed in admixture with a glycol ether cosurfactant, compositions can be formulated at a substantially neutral pH (e.g., pH 7xc2x11.5, preferably 7xc2x10.2).
The ability to formulate neutral and acidic products without builders which have grease removal capacities is a feature of the present invention because the prior art o/w microemulsion formulations most usually are highly alkaline or highly built or both.
The final essential ingredient in the inventive hard surface cleaning compositions having improved interfacial tension properties is water. The proportion of water in the microemulsion compositions generally is in the range of 20 wt. % to 97 wt. %, preferably 70 wt. % to 97 wt. % of the usual diluted o/w microemulsion composition.
In addition to the above-described essential ingredients required for the formation of the all purpose cleaning or microemulsion composition, the compositions of this invention may often and preferably do contain one or more additional ingredients which serve to improve overall product performance.
One such ingredient is a source of acidity such as hydrochloric acid or sulfuric acid for use in the formation of toilet bowl cleaners.
Another optional ingredient for use herein is an inorganic or organic salt of oxide of a multivalent metal cation, particularly Mg++. The metal salt or oxide provides several benefits including improved cleaning performance in dilute usage, particularly in soft water areas, and minimized amounts of perfume required to obtain the microemulsion state. Magnesium sulfate, either anhydrous or hydrated (e.g., heptahydrate), is especially preferred as the magnesium salt. Good results also have been obtained with magnesium oxide, magnesium chloride, magnesium acetate, magnesium propionate and magnesium hydroxide. These magnesium salts can be used with formulations at neutral or acidic pH since magnesium hydroxide will not precipitate at these pH levels.
Although magnesium is the preferred multivalent metal from which the salts (inclusive of the oxide and hydroxide) are formed, other polyvalent metal ions also can be used provided that their salts are nontoxic and are soluble in the aqueous phase of the system at the desired pH level.
Thus, depending on such factors as the pH of the system, the nature of the surfactant-polymer complex and cosurfactant, as well as the availability and cost factors, other suitable polyvalent metal ions include aluminum, copper, nickel, iron, calcium, etc. It should be noted, for example, that with the preferred fluoroalkyl anionic detergent calcium salts will precipitate and should not be used. It has also been found that the aluminum salts work best at pH below 5 or when a low level, for example 1 weight percent, of citric acid is added to the composition which is designed to have a neutral pH. Alternatively, the aluminum salt can be directly added as the citrate in such case. As the salt, the same general classes of anions as mentioned for the magnesium salts can be used, such as halide (e.g., bromide, chloride), sulfate, nitrate, hydroxide, oxide, acetate, propionate, etc.
The proportion of the multivalent salt generally will be selected so that at the appropriate weight ratio between the anionic surfactant and the polycationic polymer to deliver desired performance from the surfactant-polymer mixture in terms of adsorption properties on hard surfaces and soil antiattachment on treated hard surfaces, the physical stability of the total composition is kept, that can be impaired due to an increased hydrophobicity of the anionic surfactant in the presence of multivalent salt instead of alkali metal cation such as the sodium salt thereof. As a consequence, the proportion of the multivalent salt will be selected so that the added quantity will neutralize from 0.1 to 1.5 equivalents of the anionic surfactant, preferably 0.9 to 1.4 equivalents of the acid form of the anionic surfactant. At higher concentrations of anionic surfactant, the amount of multivalent salt will be in range of 0.5 to 1 equivalents per equivalent of anionic surfactant.
The hard surface cleaning compositions can optionally include from 0 to 2.5 wt. %, preferably from 0.1 wt. % to 2.0 wt. % of the composition of a C8-C22 fatty acid or fatty acid soap as a foam suppressant. The addition of fatty acid or fatty acid soap provides an improvement in the rinseability of the composition whether applied in neat or diluted form. Generally, however, it is necessary to increase the level of cosurfactant to maintain product stability when the fatty acid or soap is present. If more than 2.5 wt. % of a fatty acid is used in the instant compositions, the composition will become unstable at low temperatures as well as having an objectionable smell.
As example of the fatty acids which can be used as such or in the form of soap, mention can be made of distilled coconut oil fatty acids, xe2x80x9cmixed vegetablexe2x80x9d type fatty acids (e.g. high percent of saturated, mono-and/or polyunsaturated C18 chains); oleic acid, stearic acid, palmitic acid, eiocosanoic acid, and the like, generally those fatty acids having from 8 to 22 carbon atoms being acceptable.
The all-purpose liquid cleaning or microemulsion composition of this invention may, if desired, also contain other components either to provide additional effect or to make the product more attractive to the consumer. The following are mentioned by way of example: Colors or dyes in amounts up to 0.5% by weight; bactericides in amounts up to 1% by weight; preservatives or antioxidizing agents, such as formalin, 5-chloro-2-methyl-4-isothaliazolin-3-one, 2,6-di-tert.butyl-p-cresol, etc., in amounts up to 2% by weight; and pH adjusting agents, such as sulfuric acid or sodium hydroxide, as needed. Furthermore, if opaque compositions are desired, up to 4% by weight of an opacifier may be added.
In final form, the all-purpose cleaning or clear microemulsions exhibit stability at reduced and increased temperatures. More specifically, such compositions remain clear and stable in the range of 4xc2x0 C. to 50xc2x0 C., especially 10xc2x0 C. to 43xc2x0 C. Such compositions exhibit a pH in the acid or neutral range depending on intended end use. The liquids are readily pourable and exhibit a viscosity in the range of 6 to 60 milliPascalxc2x7Second (mPas.) as measured at 25xc2x0 C. with a Brookfield RVT Viscometer using a #1 spindle rotating at 20 RPM. Preferably, the viscosity is maintained in the range of 10 to 40 mPas.
The compositions are directly ready for use or can be diluted as desired and in either case no or only minimal rinsing is required and substantially no residue or streaks are left behind. Furthermore, because the compositions are free of detergent builders such as alkali metal polyphosphates they are environmentally acceptable and provide a better xe2x80x9cshinexe2x80x9d on cleaned hard surfaces.
When intended for use in the neat form, the liquid compositions can be packaged under pressure in an aerosol container or in a pump-type sprayer for the so-called spray-and-wipe type of application.
Because the compositions as prepared are aqueous liquid formulations and since no particular mixing is required to form the all purpose cleaning or microemulsion compositions, the compositions are easily prepared simply by combining all the ingredients in a suitable vessel or container. The order of mixing the ingredients is not particularly important and generally the various ingredients can be added sequentially or all at once or in the form of aqueous solutions of each or all of the primary detergents and cosurfactants can be separately prepared and combined with each other and with the perfume. The magnesium salt, or other multivalent metal compound, when present, can be added as an aqueous solution thereof or can be added directly. It is not necessary to use elevated temperatures in the formation step and room temperature is sufficient.
The instant all purpose cleaning or microemulsion composition explicitly exclude alkali metal silicates and alkali metal builders such as alkali metal polyphosphates, alkali metal carbonates, alkali metal phosphonates and alkali metal citrates because these materials, if used in the instant composition, would cause the composition to have a high pH as well as leaving residue on the surface being cleaned.
It is contemplated within the scope of the instant invention that the instant positively charged surfactant-polymer complex can be employed in hard surface cleaning compositions such as wood cleaners, window cleaners and light duty liquid cleaners.
The following examples illustrate liquid cleaning compositions of the described invention. Unless otherwise specified, all percentages are by weight. The exemplified compositions are illustrative only and do not limit the scope of the invention. Unless otherwise specified, the proportions in the examples and elsewhere in the specification are by weight.

Liquid cleaning compositions comprising fluoroalkyl sulfonate


A cushioning device for a body support such as a mattress, seat, sofa, or the like where support is obtained from a fluid. The cushioning device is self-inflating, self-adjusting, and provides a low interface pressure under the entire contact surface of a patient. Shear force scraping damage is prevented by a sleeve apparatus. A support system apparatus provides separately adjustable pressure support zones. For physical therapy, an alternating pressure system provides alternating lifting and lowering pressure zones under a patient.

The present invention relates generally to an inflatable cushioning device for body supports such as a mattress, sofa, or chair cushion. In particular, the present invention relates to a body support for preventing the formation of pressure induced soft tissue damage.
Heretofore, inflatable cushioning devices for use with body supports, such as a mattress, sofa, seat, or the like, typically included a plurality of air cells or bladders that are inflated to support a person. The air cells provide support to the person, and can be inflated to a desired pressure level to provide the person with a predetermined level of comfort and support.
In the medical field, cushioning devices including a plurality of air cells are often used to provide different levels of support under various portions of a patient""s body. For example, a mattress may include separate air cells located in the upper, middle, and lower portions of the mattress. These air cells can be inflated to different pressures to support the upper, middle, and lower portions of the patient""s body with different pressures.
In hospitals which provide care to patients confined to a bed for extended periods of time, the patients often suffer from the effects of excess pressure transmitted to their bodies. As known in the medical field, continuous pressure applied to a patient""s body can cause soft tissue damage. When the external pressure exerted on the patient""s skin causes blood carrying capillaries to close, soft tissue degeneration may occur. This soft tissue damage may lead to the formation of pressure sores. For example, continuous pressure applied to a patient""s heel can cause a pressure sore to develop on the heel. The multi-cell cushioning devices described above can be used to relieve the pressure applied to a specific portion of a patient""s body. In the case of a patient""s heel, for example, this may be accomplished by inflating the air cell under the patient""s leg so that the heel is lifted from the mattress. Thus, the continuous heel pressure is relieved and the formation of a bed sore on the heel is prevented.
Air cushion devices typically require an external pump to inflate the air cells in the device. Alternatively, the air cushion devices are pre-inflated in the manufacturing plant and are shipped to a field location for use. A problem may develop when the atmospheric pressure at the inflation location is different from the atomospheric pressure at the field location where the device is used. For example, if the field location atmospheric pressure is lower than the atmospheric pressure at the inflation location, the air cells in the field will expand and become firmer.
Hospitals rate pressure relief support systems as xe2x80x9ctreatment productsxe2x80x9d if they sufficiently reduce the pressure upon a patient""s body, reduce tissue trauma, and facilitate the healing of skin ailments, such as burns, pressure sores, etc. Typical pressure relief support systems which qualify as xe2x80x9ctreatment productsxe2x80x9d are embodied in beds which contain motors and pumps to vary the shape and pressure within the mattress. Such beds are very expensive and require the operator to undergo extensive training to learn how to use and operate the system. Furthermore, the xe2x80x9ctreatment productsxe2x80x9d often require extensive maintenance due to the failure of the numerous moving mechanical parts. Also, these complicated pressure relief support systems cannot be used on typical box spring mattress supports, and require specialized bed frames. The complicated design of these beds makes their repair very difficult, and often requires the complete replacement of the entire system for proper servicing. A further difficulty is that during power outages, these mattresses lose pressure leaving a patient on a hard surface to develop pressure sores if action is not taken. Thus, a need exists to arrive at a body support which adequately addresses these disadvantages.
The present invention provides a cushioning device for a mattress, seat, sofa, or the like where support is obtained from a fluid such as atmospheric air. The cushioning device has few moving parts, is user controllable, requires minimal maintenance, and is easily repairable. The cushioning device of the present invention includes a support system apparatus, a sleeve apparatus, a jacket, a topper cushion, and an outer cover.
The support system apparatus includes at least one support cell for providing lifting support for a body. Each support cell includes an envelope containing a fluid. Application of an external load on an outer surface of the envelope causes the envelope to deform into a compressed form. The envelope includes a reforming element that is capable of providing a reforming force to the interior surface of the envelope, to return the envelope to its original unloaded form. The reforming element is preferably made from a resilient foam material, however, other resilient means can be used.
An intake valve and an exhaust valve are included in each support cell. The exhaust valve in each support cell is connected to an exhaust control system. The intake valve in each support cell is connected to an intake control system. Each intake valve includes an intake check valve allowing fluid to flow into the support cell, while preventing fluid from flowing out of the support cell. Each exhaust valve includes an exhaust check valve allowing fluid to flow out of the support cell, while preventing fluid from flowing into the support cell. The intake control system is connected to a fluid supply reservoir. The exhaust control system is connected to a fluid exhaust reservoir. Preferably, the fluid included in the supply and exhaust reservoirs is air, however, any suitable fluid, e.g., water or nitrogen, can be used. The fluid supply and exhaust reservoirs may comprise the same reservoir, and may comprise an ambient source of fluid such as atmospheric air.
In use, the weight of a body of a person, patient, or animal resting on the envelope deforms the envelope. For illustration purposes, a patient will be used as an example of a body resting on a the envelope. The pressure of the fluid within the envelope increases as the volume of the envelope decreases under deformation. As the pressure of the fluid increases, the fluid in the envelope flows out of the envelope through the exhaust valve and into the exhaust control system. Next, the fluid flows from the exhaust control system into the fluid exhaust reservoir. Furthermore, as the envelope deforms to conform to the irregular shape of the patient, the area of the envelope supporting the load increases. Equilibrium is achieved when the forces within the envelope, including the pressure of the fluid within the envelope multiplied by the area of the envelope supporting the load, plus the force provided by the reforming element equal the weight of the load.
A controllable pressure relief valve is included in the exhaust control system so that a maximum pressure level of the fluid within the envelope can be set and maintained. Different selected maximum pressure levels of the fluid allow the support cell to accommodate different weights or allow different degrees of conformation between the patient and the envelope surface. Preferably, the maximum pressure level of the fluid is set to ensure that the interface pressure under the entire contact surface of the patient is below the pressure that may cause soft tissue damage such as pressure sores to occur.
As the weight of the patient is removed from the support cell, the reforming element exerts an outward force on the interior surface of the envelope. As the envelope expands, a partial vacuum is created in the interior space of the envelope, causing fluid to be drawn back into the interior space of the envelope. The fluid is drawn from the fluid supply reservoir into the intake control system, through the intake valve, and into the interior space of the envelope. The intake valve includes a one way intake check valve that permits fluid to re-enter the interior space of the envelope, while preventing fluid from exiting the interior space of the envelope.
The support cells included in the present invention can use atmospheric pressure as the pressure source for inflation. Therefore, when the fluid supply and exhaust reservoirs comprise atmospheric air, inflation can be accomplished without the need for expensive blowers, pumps or microprocessors as required by previously available xe2x80x9ctreatment products.xe2x80x9d A plurality of support cells can be interconnected with the intake control system and the exhaust control system to create a support system apparatus. The support system apparatus can support a patient by providing self adjusting pressure management to the entire contact surface of the patient. The support system apparatus provides a low interface pressure under the entire surface of the patient being supported. For example, if the patient is lying on the support system apparatus, the support system apparatus ensures that the interface pressure under the entire contact surface of the patient is below the pressure that may cause soft tissue damage to occur.
The support system apparatus also has the ability to self-adjust every time a patient moves, or is repositioned on the support system apparatus. When the pressure distribution applied to the support system apparatus changes, the support cells within the support system apparatus automatically inflate or deflate as necessary, to maintain a low interface pressure under the entire patient.
Another embodiment of the current invention provides for separately controlled support zones within the support system apparatus. Each support zone comprises at least one support cell. Each support cell includes at least one intake valve and at least one exhaust valve. The intake valve for each support cell in each support zone is connected to the intake control system. The exhaust valves from each support cell in a single support zone are connected to a single exhaust control system. Each support zone has a separate exhaust control system. The intake control system is connected to the fluid supply reservoir. The exhaust control system for each support zone is connected to the fluid exhaust reservoir. Generally the pressure level in each support zone is set at a different level. For example, if the support system apparatus comprises a mattress in a bed, the upper, middle, and lower zones of the support system apparatus can be set to provide a different level of pressure or firmness for the upper, middle, and lower portions of the patient""s body.
The sleeve apparatus includes a cell cover surrounding each support cell. For a plurality of support cells, each cell cover is attached to an adjacent cell cover. The cell cover allows the surface of the envelope of the support cell to slide freely along a first side of the cell cover, without transmitting this sliding movement to a second side of the cell cover. The second side of the cell cover can be the side on which a patient is lying. Therefore, movement of the support cell is not transmitted to the patient, thereby preventing frictional or shear force abrasion damage to the skin of the patient. In the event that repair of a support cell becomes necessary, the sleeve apparatus allows each support cell to be easily removed and replaced.
Another embodiment of the present invention provides an additional alternating pressure system for providing alternating supply pressure to a plurality of zones. The alternating pressure system can be used in combination with the support system apparatus. Each zone includes at least one support cell. The alternating pressure system includes a pressurized fluid supply source including a pump, a pressurized fluid tank, etc. Additionally, the alternating pressure system includes a control system for sequentially supplying fluid pressure to the plurality of zones. The raising and lowering of the alternating zones under a patient provides beneficial movement of the skeleton and tissue in the patient. The movement helps stimulate circulation and lymph fluid movement in the patient. When the alternating pressure system is deactivated or fails, the support system apparatus continues to provide self adjusting pressure management to the patient""s body.
The jacket houses the support system apparatus, the intake and exhaust control systems, and portions of the alternating pressure system. The jacket can be made from any suitable stretchable material, and is preferably is formed from a stretchable fabric material.
The topper cover provides further resilient torso support. The topper cover may be formed from a layered fiber filled material or other suitable material. The topper may include a resilient heel support unit to reduce pressures on the sensitive heel region of a patient. The topper cover may rest above the jacket, and may be covered by the outer cover. Alternatively, the topper cover may rest above the support system apparatus.
The outer cover provides a low friction and low shear surface further protecting the patient from frictional tissue damage. Additionally, the outer cover provides a waterproof and stain resistant surface. For medical uses the outer cover can be made from an anti-microbial type material.
The cushioning device of the present invention allows a user in the field to adjustably set the maximum pressure level in each support cell. When surrounded by atmospheric air, the support system apparatus is self-inflating, self-adjusting, and does not require expensive pumps and control systems as required by related xe2x80x9ctreatment productxe2x80x9d art. Also, since there are fewer moving parts in the present invention, maintenance and repairs are simple and reasonable in cost compared to the complex related art.
The cushioning device of the present invention can be used in combination with any support device where self adjusting dynamic pressure support of the person or patient is required. For example, these support devices can be mattresses, sofas, seats, etc.
Generally, the cushioning device of the present invention comprises:
a plurality of fluid cells; and
a non-powered manifold system, operatively attached to the plurality of fluid cells.
The present invention additionally provides a cushioning device comprising:
a plurality of self-inflating fluid cells;
a manifold system, operatively attached to the plurality of self-inflating fluid cells; and
means, operatively attached to the self-inflating fluid cells for adjusting the firmness or softness of all of the fluid cells.
The present invention additionally provides a cushioning device comprising:
a plurality of self-inflating fluid cells;
a manifold system, operatively attached to the plurality of self-inflating fluid cells; and
a pressure regulator attached to the manifold system.
The present invention additionally provides a cushioning device comprising:
a plurality of fluid cells;
a pressure regulator; and
a manifold system, operatively attached to each of the fluid cells, wherein the fluid cells do not communicate with each other through the manifold and all fluid cells communicate with the pressure regulator.
The present invention provides a method for supporting a body comprising:
providing a plurality of non-powered self-inflating fluid cells;
applying a body weight to the non-powered self-inflating fluid cells; and
allowing each of the non-powered self-inflating fluid cells to react to the body weight and adjust to an identical internal pressure.

Inflatable cushioning device with manifold system


A filter-antenna and a method for making a filter-antenna. The filter antenna includes a microstrip antenna, such as a patch antenna, integrated with an absorptive (e.g., bandstop) filter for absorbing or dissipating energy.

Filters and antennas are common and important components in communication devices. A filter-antenna (or filtering-antenna) is a device that combines an antenna and a filter.
Existing filter-antennas are reflective filter-antennas. These reflective filter-antennas reflect most of the incident energy in the stopband. The reflected energy may be transferred to other components (e.g., a power amplifier associated with the filter-antenna) in the system, which may lead to instability (e.g., self-oscillation in the power amplifier). One option to avoid or mitigate this instability problem is to use isolators, circulators, and/or attenuators in the system to reduce the effect of the reflected energy on the system. However, this option would increase the number of the components in the system, making the system cumbersome and expensive while potentially increasing the insertion loss.

Filter-antenna and method for making the same