A method for printing carbonless forms on an electrostatic printer or copier and carbonless forms for use in electrostatic printers or copiers are disclosed. A method of printing carbonless forms comprises providing a recording sheet comprising a substrate, the substrate being coated with a coated front (CF) coating comprising a developer, hollow microspheres and a binder composition, wherein the binder composition comprises polyvinyl alcohol and printing on the recording sheet with an electrostatic printer or copier.

The present invention relates to carbonless copy paper, and more specifically to a carbonless CF recording sheet capable of being run on electrostatic copiers and printers without contaminating the components of the electrostatic device.
Carbonless copy systems and other copying systems employing a color precursor and a developer are well known in the art. These systems can comprise two sheets, a transfer or donor sheet which contains a colorless color-forming agent on one of its surfaces which is often contained in pressure rupturable microcapsules and a developer or receiver sheet, which is typically a substrate having a layer of a developer material coated onto its front surface which can react with the colorless color-forming agent to form a visible image. In practice, to produce an image, the two sheets are juxtaposed so that the colorless color-forming agent faces the developer material. Upon the application of pressure, such as a pen, pencil, typewriter, or other writing instrument, the microcapsules are ruptured which releases the colorless color-forming agent. The color-forming agent reacts with the developer material on the developer sheet to form a visible image.
Carbonless papers are widely used in the forms industry. Typically, preprinted forms are compiled into a set or packet such that marking the top form will provide the required number of duplicates. In one instance, the carbonless paper is prepared in precollated sets wherein sheets of various colors and surfaces are packaged in reversed sequence sets wherein the sheets are arranged opposite to their normal functional order. That is, the CF sheet is first in the set with the CB sheet being last, with the required number of CFB sheets therebetween. When the sheets are then printed in a printer which automatically reverses their sequence in the delivery tray, they will end up in the proper functional order for subsequent data entry. Where reversal of the sequence in the delivery tray does not occur, precollated sheets can be arranged in their normal functional order.
Traditionally, carbonless paper forms have been printed by conventional printing techniques, such as offset lithography, etc. With the advent of high speed electrostatic copiers having dependable, high capacity collating systems, has come the natural attempts to print carbonless paper by such techniques. Such attempts initially encountered problems, because the specialty coatings on the sheet would tend to shear or pick off the sheet resulting in contamination of the electrostatic device. Cost prohibitive maintenance to clean the machine on a frequent basis was necessary for satisfactory operation of the copier and production of an acceptable product. The heat and pressure utilized in the electrostatic devices would cause transfer of the coating components to elements of the paper and toner transport systems in the electrostatic device. After a number of sheets were printed, the contamination in the device would cause specks of toner powder to be deposited on the sheet. Many of these aforementioned problems were attributable to the microcapsule coating on the CB sheet. Reformulation and modification of the CB coating resolved many of these problems relating to contamination from the microcapsules and the inadvertent rupture thereof which caused premature release of the encapsulated contents and contamination of the electrostatic device.
Contamination of electrostatic copiers and printers has again become problematic due to changes in the feed and printing mechanisms in recently developed electrostatic devices. The new machines are believed to subject the paper being printed to increased levels of heat and pressure not previously encountered during the electrostatic printing process. The increased heat and pressure as well as the faster speeds associated with the newer devices are believed to be responsible for the current contamination problems encountered when using prior art carbonless systems.
Applicants have discovered that the contamination with the newer electrostatic devices is originating with the CF coating rather than the CB coating. As the CF sheet is fed through the paper transport system of the printer or copier, it encounters various pressure points in the device, such as, for example, feed belts and wheels, retard rollers, pinch rollers and the like. When the sheet is passed through these points, often under elevated temperatures, there is intimate contact between the pressure point and the sheet which can result in contamination of the device with components of the CF coating and have deleterious effects on the continued operation of the printer or copier. Simply increasing the amount of binder in the CF formulation may improve binding of the various CF components and thereby reduce contamination. However, an increase in binder levels typically results in a corresponding decrease in product performance characteristics, such as intensity.
Accordingly, there is a need for a carbonless paper capable of being printed on an electrostatic copier or printer without excessive contamination; a paper capable of being run on a copier or printer without requiring excessive machine maintenance; and a carbonless paper, and in particular a recording paper, having improved binding power to prevent contamination without adversely affecting imaging properties. There is also a need for a method of producing a carbonless form using an electrostatic printer or copier wherein the carbonless paper will not contaminate the components of the device and excessive maintenance is not required.
This invention provides an improved carbonless copy paper, and in particular an improved carbonless CF recording sheet which is capable of being printed on an electrostatic copier or printer without excessive contamination and without requiring excessive maintenance to enable continued operation of the printer or copier. It has been found that, in accordance with the invention, the binder portion of the CF coating can be increased without adversely affecting imaging properties. In accordance with a preferred embodiment of the invention, polyvinyl alcohol mixed with latex is used to improve binding of the pigments in the CF coating while avoiding film formation which can be detrimental to image intensity and speed of development. In another preferred embodiment, an improved binder based on PVA and starch prepared as a cooked pre-mix is used to provide improved binding of the CF coating without adversely affecting imaging properties.
In describing the preferred embodiment, certain terminology will be utilized for the sake of clarity. It is intended that such terminology include not only the recited embodiments but all technical equivalents which operate in a similar manner, for a similar purpose, to achieve a similar result.
The recording sheet of the present invention may be used in any imaging system in which a color precursor is reacted with a developer to form an image. More particularly, it may be used in pressure-sensitive transfer recording systems, pressure-sensitive self-contained recording systems, and thermal or heat-sensitive recording systems.
In accordance with another embodiment, the recording sheet of the present invention may be used in a photosensitive recording system. Photosensitive compositions, photoinitiators, color formers, wall formers, encapsulation techniques and developer materials useful in photosensitive recording systems are described in U.S. Pat. Nos. 4,399,209; 4,772,530; and 4,772,541 are useful herein. These patents are incorporated herein by reference.
The recording sheet includes a substrate having a front surface and a back surface. The substrate is typically paper but in certain applications it may be made of transparent polymeric materials such as polyethylene terephthalate, translucent substrates, opaque polymeric substrates such as Melinex 329 and Melinex 470 sold by ICI Americas, or polymer coated paper materials such as commercially available photographic papers and plain paper.
Any of the developer materials that have been conventionally used or taught for use in any of the aforesaid recording systems should be useful in the recording sheets of this invention. The developer material is selected such that it reacts with the color precursor to produce a high density image. In the most typical embodiments, the color precursor is a substantially colorless electron donating compound of the type conventionally used in the pressure-sensitive recording art and the developer material is a solid particulate electron accepting compound.
The developer can be selected from among the developers conventionally used in carbonless paper including acid clay, active clay, attapulgite, etc.; organic acids such as tannic acid, gallic acid, propylgallate; aromatic carboxylic acids such as benzoic acid, p-tert-butyl-benzoic acid, 4-methyl-3-nitro- benzoic acid, salicylic acid, 3-phenyl salicylic acid, 3-cyclohexyl salicylic acid, 3-tert-butyl-5-methyl salicylic acid, 3,5-ditert-butyl salicylic acid, 3-methyl-5-benzyl salicylic acid, 3-phenyl-5-(xcex1,xcex1-dimethylbenzyl)salicylic acid, 3-cyclohexyl-5-(xcex1,xcex1-dimethylbenzyl)salicylic acid, 3-(xcex1,xcex1-dimethylbenzyl)-5-methyl salicylic acid, 3,5-dicyclohexyl salicylic acid, 3,5-di-(xcex1-methylbenzyl)salicylic acid, 3,5-di-(xcex1,xcex1-dimethylbenzyl)salicylic acid, 3-(xcex1-methylbenzyl)-5-(xcex1,xcex1-dimethylbenzyl)salicylic acid, 4-methyl-5-cyclohexyl salicylic acid, 2-hydroxy-l-benzyl-3-naphthoic acid, 1-benzoyl-2-hydroxy-3-naphthoic acid, 3-hydroxy-5-cyclohexyl-2-naphthoic acid and the like, and polyvalent metallic salts thereof such as zinc salts, aluminum salts, magnesium salts, calcium salts and cobalt salts as disclosed in U.S. Pat. Nos. 3,864,146; 3,924,027 and 3,983,292; phenol compounds such as 6,6xe2x80x2-methylene-bis(4-chloro-m-cresol) as disclosed in Japanese Patent Publications 9,309 of 1965 and 20,144 of 1967, and Japanese Laid Open Patent Publication No. 14,409 of 1973; acid polymers such as maleic acid-rosin resin and copolymers of maleic anhydride with styrene, ethylene or vinylmethylether; and aromatic carboxylic acid-aldehyde polymers, aromatic carboxylic acid-acetylene polymers and their polyvalent metallic salts as disclosed in U.S. Pat. Nos. 3,767,449 and 3,772,052.
Preferred developer materials are phenolic resins, such as phenol-aldehyde resins e.g., p-phenyl-phenolformaldehyde resin; phenol-acetylene resins, e.g., p-tert-butylphenol-acetylene resin; polyvalent metallic salts thereof such as zinc modified phenol formaldehyde resin as disclosed in U.S. Pat. No. 3,732,120, and phenolic resins modified to include amounts of unsubstituted or substituted salicylic acids in a manner known in the art. One class of phenolic resin useful in the present invention is the product of oxidative coupling of substituted or unsubstituted phenols or bisphenols. Oxidative coupling may be catalyzed by various catalysts but a particularly desirable catalyst is the enzyme peroxidase. Particularly desirable developers are the resins described in commonly assigned U.S. Pat. No. 4,647,952, which is incorporated herein by reference, and more particularly the product of oxidative coupling of bisphenol A.
Especially preferred developer materials are phenol-formaldehyde condensation products. More particularly, alkylphenolic resins and, still more particularly, metallated products of alkylphenolic resins are preferred. The alkyl phenols are monosubstituted by an alkyl group which may contain 1 to 12 carbon atoms. Examples of alkyl phenols are ortho- or para- substituted ethylphenol, propylphenol, butylphenol, amylphenol, hexylphenol, heptylphenol, octylphenol, nonylphenol, t-butylphenol, t-octylphenol, etc. Another class of thermoplastic developer material which may be used within the scope of the present invention is a resin-like condensation product of a polyvalent metal salt, such as a zinc salt, and a phenol, a phenol-formaldehyde condensation product, or a phenol-salicylic acid-formaldehyde condensation product.
Useful phenolic developer resins are available from Schenectady Chemical Co. under the designations HRJ 2629, BRJ 2969, HRJ 4250 and HRJ 4542. The latter two products are reported to be a metallated condensation product of an ortho- or para-substituted alkylphenol, a substituted salicylic acid, and formaldehyde.
A binder is used to improve the scuff resistance of the recording layer and to provide adequate adhesion between the coating and the substrate. The amount of binder used in the composition will vary depending upon the nature of the binder material. In accordance with the present invention, the amount of binder used is determined based on the amount necessary to securely anchor the components of the recording coating to the sheet in order to avoid contamination without adversely affecting imaging properties. The total binder content typically will fall within the range of about 2 to 30% and more typically about 8 to 20% based on solids.
A binder used in the present invention is mixed with the developer resin to form a developer coating. The binder acts to enhance the surface strength of the coating as well as to adhere the coating to the substrate. In a preferred embodiment, a strong synthetic binder, such as polyvinyl alcohol, is used to provide enhanced binding strength. Additional synthetic and/or natural binders can also be added. Synthetic binders are typically preferred because they are stronger than natural binders and the surface strength of the developer sheet can be maintained without affecting image development. Illustrative examples of other synthetic binders which can be used include polyvinyl acetate and copolymers thereof, styrene butadiene rubber (SBR), polystyrene, butadiene-styrene copolymers, polyvinylpyrrolidone, acrylic homo- or copolymers such as acrylic or methacrylic acids or lower alkyl esters thereof, e.g., ethyl acrylate, butyl acrylate and methyl methacrylate, acrylamide and the like. Especially preferred synthetic binders are latexes such as sytrenebutadiene latexes, carboxylated sytrenebutadiene latexes, acrylic latexes, and acrylonitrile latexes. Latex binders, when present, typically fall within the range of about 2 to 10% and more typically 3 to 6% by dry weight of the coating composition. One example of a commercially available latex useful in the present invention is sold under the trade designation Genflo Latex 5100 from Omnova. Illustrative examples of natural binders are gum arabic, casein, sodium alginate, methyl cellulose, carboxymethyl cellulose, dextrin, starch or modified starches, e.g., oxidized, hydrolyzed or hydroxyethylated starch, and the like.
The microspheres used in the present invention are hollow spherical pigment particles made from a synthetic organic polymer or any inorganic shell-forming material such as glass or sodium silicate. Typically such microspheres have a diameter of approximately 0.3xcexc to 15xcexc and preferably about 1.0 micron. Such hollow synthetic organic pigment particles are known in the art and are commercially available from Rohm and Haas Corp. The microspheres provide a network of gas-filled voids in the developer layer. Furthermore, it is believed that the microspheres help to prevent the binder from forming a film on the surface of the sheet. One example of a commercially available microspheres that is useful in the present invention is sold under the trade designation HP-1055 from Rohm and Haas. Hollow polymer particles which are useful in this invention may be made in accordance with and having the properties disclosed in U.S. Pat. Nos. 3,784,391; 4,798,691; 4,908,271; 4,910,229; and 4,972,000; and Japanese Patent Applications 60/223873; 61/62510; 61/66710; 61/86941; 62/127336; 62/156387; 01/185311; and 02/140272; U.S. Pat Nos. 4,427,836;4,469,825; 4,594,363; and 4,880,842. The disclosures therein related to the manufacture and composition of the hollow polymer particles are incorporated herein by reference. The preferred pigment has a soft compressible quality that yields a microscopic void under the application of writing or marking pressure.
The recording layer may also include in the coating solution a viscosity increasing additive, typically a water-soluble material, which significantly increases the viscosity of the coating layer upon removal of the coating solvent. Further optionally incorporated with the thermoplastic developer material is one or more dispersing agents (e.g., Dispex N-40, polymeric carboxylic acid from Allied Colloids, Inc.). Other commonly utilized additives such as anti-foaming agents, structured clays (e.g., Exsilon 87 and Ansilex 93 from Englehard Corp., as described in U.S. Pat. No. 5,350,729 to Londo et al.), optical whitening agents (e.g., Tinopal PT-150 from Ciba Geigy Corp.) and lubricants (e.g., Nopcote C-105HS calcium stearate dispersion from Henkel Corp.) may also be added in minor amounts.
To produce the recording sheet, the developer material is dispersed in a liquid, typically water, to form a resin dispersion, and binder material, microspheres, and optional additives are mixed into the dispersion. Once the dispersion is well mixed, it is coated onto the support by coating means known in the art. For example, a Meyer bar coater may be used. In practice, the developer layer is applied in an amount of about 1.0 to 2.0 pounds per 1700 sq. ft.
The developer resin is used in an amount sufficient to react with a color precursor and form as image. In a preferred embodiment, the developer layer contains about 4 to 40% developer and about 5 to 50 wt. % microspheres. Preferably, the amount of developer resin used is about 10% to 25% and the amount of microspheres is about 7 to 20% based on dry weight.
In accordance with the invention, binder levels of the recording layer are increased such that the coatings can be run for extended periods of time on an electrostatic printer or copier without excessive contamination or downtime for maintenance. In a preferred embodiment, polyvinyl alcohol (PVA) is added at elevated levels to better hold the pigments in the recording layer coating. The amount of PVA on a dry basis typically is between 2 and 12%, preferably between 4 and 9%. In the preferred embodiment, the polyvinyl alcohol is cooked with a starch to prepare a pre-mix which is then used to prepare a CF recording layer coating composition in accordance with the present invention. The amount of starch used typically is about 2 to 25%, preferably about 4 to 20% based on dry weight.
One embodiment of the present invention is a developer sheet which minimizes contamination in electrostatic printers or copiers and yet also provides improved image intensity through one or a combination of mechanisms. Although not wishing to be bound by theory, applicants believe that the starch-PVA pre-mix prevents formation of a PVA barrier film which otherwise would interfere with imaging capabilities of the carbonless form. By avoiding the formation of a film, the starch-PVA pre-mix facilitates penetration of the color oil (from ruptured CB microcapsules) into the developer layer and into contact with the color developing resin, thereby forming an image.
The present invention also provides a method for printing carbonless forms on an electrostatic printer or copier which comprises providing a recording sheet having a developer and a binder, wherein the binder comprises one or more synthetic binders, preferably a combination of polyvinyl alcohol and latex, and printing on the recording sheet with an electrostatic printer or copier. Carbonless forms printed in accordance with the present invention can be run sequentially for an extended period of time without causing contamination of the electrostatic printer or copier. The method of the invention avoids expensive printer downtime for cleaning typically required for electrostatic printing of conventional carbonless.
The present invention is also directed to a process for electrostatically printing carbonless sheets and producing a carbonless formset. The carbonless formset contains a plurality of sheets, including at least a first substrate containing a coating of an encapsulated color former and a second substrate containing a second coating of a color developer. The first and second substrates are positioned such that the first and second coatings are juxtaposed. The second coating comprises a color developer in a binder matrix of polyvinyl alcohol and latex. Formsets are produced by applying adhesive to the formset sheets after the sheets have been printed on the electrostatic copier or printer, such that the first and second substrates are collated as a set. Formsets of three plies or more can be prepared by providing one or more CFB sheets between the first (CB) and second (CF) substrates.


Physically-based volume rendering generates a lightfield. The locations of scattering modeled in physically-based rendering are used to assign depths for the lightfield. The previously assigned depths and previously rendered lightfield are used for lightfield rendering, which may be performed more rapidly than the physically-based volume rendering.

The present embodiments relate to physically-based volume rendering. In a medical imaging example, an image from a three-dimensional (3D) scan of a patient is rendered for visualization.
Physically-based visualization techniques produce global illumination effects in computer-generated graphics that mimic the real-world interaction of light with various 3D objects or tissues. Monte Carlo path tracing is a useful rendering technique for such light transport computations, where the natural light phenomena are modeled using a stochastic process. The physically-based volume rendering results in physically plausible images that are often easier for the human brain to interpret when compared to the more analytical images from traditional volume rendering, such as ray casting or direct volume rendering. However, evaluation of the rendering integral in physically-based volume rendering may require thousands of stochastic samples per pixel to produce an acceptably noise-free image. Depending on the rendering parameters and implementing processor, producing one photorealistic image with physically-based volume rendering may be on the order of seconds for interactive workflows and multiple hours for production-quality images.
Light field rendering allows much faster generation of photorealistic images, but depends on a large amount of input data that has to be produced in an expensive preprocessing step. This preprocessing step shifts the time demand form the phase of the user interaction to the preprocessing step. This also allows fast rendering on low-powered devices, like tablets or cell phones, while shifting the computationally expensive task of preprocessing to dedicated computer servers.

Lightfield rendering based on depths from physically-based volume rendering


A decorative clasp closes by magnetic action, and can be worn on the front, i.e. at the throat or beneath the throat. The clasp allows the loop size of the jewelry article to be adjusted to suit the wearer's preferences. A pair of arcuate arms are joined at a pivot member, and close magnetically to form a generally oval shape.

This invention relates to jewelry clasp in which one end of a string or strand of beads, i.e., a necklace or bracelet, is attached to the clasp, and a hinged oval loop or bight closes over the string or strand near the other end, i.e., between two beads on the jewelry article. The invention is more specifically directed to a decorative clasp which closes by magnetic action, and which can be worn on the front, i.e. at the throat or beneath the throat, and which allows the loop size of the jewelry article to be adjusted to suit the wearer's preferences.
Typically, clasps for closing a necklace or similar string of beads, pearls, or gemstones employs a two-part mechanical clasp of which one part is attached to one end of the string or strand, and the other mating part is attached to the other end. These are usually mechanical closures, although in some cases magnetic action has been employed. One example of a magnetic clasp for a necklace is discussed in Fuhrman et al. U.S. Pat. No. 7,334,433. A magnetic clasp is also discussed in Ito U.S. Pat. No. 6,349,568, in which the clasp is of the center-bend type, formed of a pair of arcuate members that pivot from one end attached to the end of the necklace, with the mouth of the clasp being closed by magnets at the free ends of these members. Alternatively, the clasp may be formed of a soft resin such as polyethylene folding in half and closed magnetically.
An ornamental closure or hook for latching one end of a strand of pearls at a place between two pearls near the other end is discussed in Ito U.S. Pat. No. 7,024,886. This may be worn in front. However, the device requires mechanically placing a hook in the space between two pearls. Other decorative front-mounted pearl necklace shorteners have appeared as well, e.g., in Bohlinger et al. U.S. Pat. No. 3,225,565. These typically require a great deal of finger dexterity to attach and release, and often cannot provide the desired appearance to match the look of the string of beads or pearls.


Peptide-modified polyurethanes comprising the reaction product of an isocyanate, a chain extender, and a peptide are provided. Also provided processes for making a peptide-modified polyurethane comprising: providing an isocyanate; providing a chain extender; providing a peptide; and allowing the isocyanate, chain extender, and peptide to react thereby forming the peptide-modified polyurethane, as well as methods for treating a subject comprising: providing a peptide-modified polyurethane that comprises the reaction product of an isocyanate, a chain extender, and a peptide; and administering the peptide-modified polyurethane to the subject.

The present invention generally relates to peptide-modified polyurethane compositions and methods of using such compositions. These compositions have improved properties that make them useful for a variety of applications, including, in particular, the manufacture of medical devices, articles, or implants that contact living tissues or bodily fluids.
Polyurethanes represent a major class of synthetic polymers that have been evaluated for use with a variety of medical implants. Polyurethanes have favorable mechanical properties (e.g., high tensile strength, tear and abrasion resistance, and stability in biological environments) and are generally biocompatible. Accordingly, polyurethanes are used with medical implants such as cardiac pacemakers, catheters, implantable prostheses, cardiac assist devices, heart valves, and vascular grafts. The favorable mechanical properties of some polyurethanes can be attributed to their two-phase morphology, which is derived from microphase separation of soft and hard polymer segments. The soft segment has a low glass transition temperature (Tg), and the hard segment has a high Tg. For polyurethanes used with certain medical implants, the soft segments may be formed from a polyether polyol such as polytetramethylene oxide (PTMO), and the hard segments may be derived from a diisocyanate such as 4,4′-methylenediphenyl diisocyanate (MDI) and a polyol chain extender such as 1,4-butanediol.
Vascular grafts are a type of medical implant in which synthetic polymers are useful. Certain vascular diseases often result in a need to open, replace, or bypass diseased or damaged blood vessel segments. In these situations, a graft may be used to direct blood flow around occluded segments of the vasculature, commonly referred to as bypass grafting. In coronary artery bypass grafting (CABG), occluded coronary arteries can be replaced with autologous tissue such as saphenous veins. But, some patients may not have suitable donor tissue, e.g., due to peripheral vascular disease or prior surgery, and a synthetic blood vessel substitute or graft may be required.
Synthetic polymers such as ePTFE (expanded polytetrafluoroethylene), Dacron (polyethylene teraphthalate), and microporous polyurethanes have been developed for use with synthetic grafts and other medical implants. In large-diameter (e.g., >6 mm) applications, these synthetic polymers have been successfully used as vascular grafts, but generally are not suitable for small-diameter applications such as CABG. In small-diameter applications, synthetic grafts often become occluded, decreasing the patency of the graft. Similarly, grafts with low blood flow are more susceptible to patency failure as compared to those in high blood flow. Thus, synthetic grafts are used infrequently for bypass or reconstructive procedures that require small diameters, such as the coronary artery and arteries below the knee.
Compliance also affects the function of small-diameter synthetic grafts. Vascular compliance is the ability of a blood vessel wall to expand and contract passively with changes in pressure and constitutes an important function of large arteries and veins. The compliance of a blood vessel generally is a structural property, which depends on the geometry (diameter and wall thickness) of the blood vessel, rather than a material property. To avoid discontinuity of blood-flow velocity, the compliance of a graft should match the compliance of the vessel it is replacing. Generally, smaller synthetic grafts are unable to meet the compliance requirements of small-diameter vessels.
Endothelialization of synthetic grafts may improve graft patency and improve a synthetic polymer's blood compatibility. Patency and compatibility, however, may be dependent on the attachment and retention (e.g., proliferation and migration) of endothelial cells on the graft or polymer surface. This dependency may be problematic since endothelial cells are known to detach upon exposure to physiological shear stresses. One way to adhere and retain endothelial cells on a synthetic polymer is to modify the polymer's surface. A number of surface modification strategies exist, such as attaching ionic groups, heparin, thrombomodulin, and growth factors to the graft or synthetic polymer. Another approach is to attach cell surface receptors and adhesion proteins ("adhesive peptides"), which are capable of mediating cell adhesion, to the surface of a synthetic material. For example, modifications of materials with adhesive peptides that promote integrin-mediated cell attachment, such as the RGD (arginine-glycine-aspartic acid) peptide, promote cell adhesion and spreading. RGD is known to interact with platelet integrin glycoprotein IIB/IIIA, so while RGD may enhance endothelial cell adhesion, it ultimately may decrease graft performance. The laminin-derived peptide YIGSR (tyrosine-isoleucine-glycine-serine-arginine), which binds nonintegrin receptors on endothelial cells, also may promote endothelialization when attached to synthetic polymers.
In general, the degradability of a synthetic material used with a medical implant should be considered. In some applications, degradable materials (e.g., poly(lactic acid)) are advantageous because they can be used for both tissue engineering and delivery of therapeutic agents to the implantation site. For example, cells may attach and grow on a degradable material, proliferate, and eventually adsorb and replace the material. These degradable materials are often degraded in vivo by hydrolysis or enzymatic mechanisms. To decrease thrombosis, degradable materials modified with adhesive peptides have been tested. For example, RGD has been attached to degradable block copolymers of biotinylated polyethylene glycol (PEG) with poly(lactic acid) (PLA) and poly(lactic acid-co-lysine).
The physiological response to a medical implant often includes platelet adhesion, platelet aggregation, and smooth muscle cell proliferation. In turn, this results in neointimal lesions at the implant placement site. Nitric oxide (NO) is a natural mediator of vascular homeostasis, and known to be a vasodilator, a regulator of vascular cell proliferation and migration, and an inhibitor of thrombus formation. NO has been shown to decrease the incidence of intimal hyperplasia in several animal models, and the inhibition of platelet adhesion and aggregation by NO and several NO-releasing materials has been reported. Synthetic materials that are capable of releasing NO may therefore be suitable for use with medical implants. However, the rate at which such materials release NO may be important. For example, if the release rate is too high, a dose of NO may cause a cytotoxic response, while too little may not stimulate endothelial cell proliferation to a desired degree or inadequately inhibit platelet adhesion and cell growth.

Peptide-modified polyurethane compositions and associated methods


Structured surfactant systems contain a deflocculant and, in addition, an auxiliary stabiliser to inhibit temperature instability. The auxiliary stabiliser comprises a substantially non cross-linked water soluble copolymer having a hydrophulic back-bone and sufficient C2-6 hydrophobic organic side chains to permit entanglement of the polymer chains.

The present invention relates to the formulation of structured surfactant suspending systems. It is particularly relevant to the formulation of laundry detergents especially those used for industrial and institutional cleaning.
Suspending solids in liquids presents a problem. If the solids differ in density from the liquid they will tend either to sediment or float. Increasing the viscosity of the liquid can retard, but not prevent such separation, and high viscosities are generally undesirable. Colloidal systems, in which the suspended particles are sufficiently small to experience Brownian motion, e.g. less than 1 micron, may be kinetically stable. However the difficulty or undesirability of comminuting some solids to such sizes, and the impossibility of maintaining many of them at this level in the face of crystal growth or agglomeration, limits the use of colloidal suspensions.
Adjusting the density of one phase to match that of the other is usually impracticable. Moreover such systems are almost always temperature-unstable due to differential rates of thermal expansion.
One method of suspension which permits even relatively large particles to be stably suspended is structured surfactant The term covers systems in which a surfactant mesophase, usually a lamellar or G-phase, alone or more usually interspersed with an aqueous phase, provides a yield stress which is sufficient, when the system is at rest, to immobilise any suspended particles, but which is sufficiently low to allow the system to be poured like a normal liquid. Such systems may display very low apparent viscosities when stirred, pumped or poured and yet be capable of maintaining particles, sometimes of millimeter or larger size, indefinitely in suspension.
Three main types of suspending system have been employed in practice, all involving a G-phase, in which bilayers of surfactant are arranged with the hydrophobic part of the molecule on the interior and the hydrophilic part on the exterior of the bilayer (or vice versa). The bilayers lie side by side, e.g. in a parallel or concentric configuration, sometimes separated by aqueous layers. G-phases (also known as Lxcex1 phases) can usually be identified by their characteristic textures under the polarising microscope and/or by x-ray diffraction, which is often able to detect evidence of lamellar symmetry. Such evidence may comprise first, second and sometimes third order peaks with d-spacing   (                    2                Π            Q                  xe2x80x83            where              xe2x80x83            Q              xe2x80x83            is              xe2x80x83            the              xe2x80x83            momentum              xe2x80x83            transfer              xe2x80x83            vector    )
in a simple integral ratio 1:2:3. Other types of symmetry give different ratios, usually non integral.
Most surfactants form a G-phase either at ambient or at some higher temperature when mixed with water in certain specific proportions. However such G-phases cannot usually be used as structured suspending systems. Useful quantities of solid render them unpourable and smaller amounts tend to sediment.
The main types of structured system used in practice are based on dispersed lamellar, spherulitic and attenuated lamellar phases. Dispersed lamellar phases are two phase systems in which the surfactant bilayers are arranged as parallel plates to form domains of G-phases which are interspersed with an aqueous phase to form an opaque gel-like system. They are described in EP O 086 614.
Spherulitic phases comprise well defined spheroidal bodies, usually referred to in the art as spherulites, in which surfactant bilayers are arranged as concentric shells. The spherulites usually have a diameter in the range 0.1 to 15 microns and are dispersed in an aqueous phase in the manner of a classical emulsion, but interacting to form a structured system. Spherulitic systems are described in more detail in EP O 151 884.
Many structured surfactant systems are intermediate between dispersed lamellar and spherulitic, involving both types of structure. Usually systems having a more Spherulitic character are preferred because they tend to have lower viscosity. A variant on the spherulitic system comprises prolate or rod shaped bodies sometimes referred to as batonets.
A third type of structured surfactant system comprises an expanded G-phase. It differs from the other two types of structure system in being essentially a single phase, and from conventional G-phase in having a wider d-spacing. Conventional G-phases have a d-spacing of about 5 to 7 nanometers. Attempts to suspend solids in such phases results in stiff pastes which are either non-pourable, unstable or both Expanded G-phases with d-spacing between 8 and 20, e.g. 10 to 15 nanometers, form when the electrolyte is added to aqueous surfactants at concentrations just below those required to form a normal G-phase, particularly to surfactants in the M phase. The M phase comprises surfactant molecules arranged to form cylindrical rods of indefinite length. It exhibits hexagonal symmetry and a distinctive texture under the polarising microscope. Typical M phases have so high a viscosity that they appear to be curdy solids. M phases near the lower concentration limit (the L1/M phase boundary) may be pourable but have a very high viscosity and often a mucous-like appearance. Such systems tend to form expanded G-phases particularly readily on addition of sufficient electrolyte.
Expanded G-phases are described in more detail in EP O 530 708. In the absence of suspended matter they are translucent, unlike dispersed lamellar or spherulitic phases which are necessarily opaque. They arm optically anisotropic and have shear dependent viscosity. In this they differ from L1 phases which are micellar solutions and which include microemulsions. L1 phases are clears optically isotropic and substantially Newtonian. They are unstructured and cannot suspend solids. Some L1 phases exhibit small angle x-ray diffraction spectra which show evidence of hexagonal symmetry. Such phases usually have concentrations near the L1/M phase boundary and may form expanded G-phases on addition of electrolyte.
Most structured surfactant systems require the presence of electrolyte as well as surfactant and water in order to form structured systems capable of suspending solids. However certain relatively hydrophobic surfactants such as isopropylamine alkyl benzene sulphonate can form spherulites in water in the absence of electrolyte. Such surfactants are capable of suspending solids in the absence of electrolyte as described in EP O 414 549.
A problem with the two phase structured surfactant systems, and especially spherulitic systems, is flocculation of the dispersed surfactant structures. This tends to occur at high surfactant and/or high electrolyte concentration. It can have the effect of making the composition very viscous and/or unstable with the dispersed surfactant separating from the aqueous phase.
Certain amphiphilic polymers have been found to act as deflocculants of structured surfactants. One type of deflocculant polymer exhibits cteniform (comb-shaped) architecture with a hydrophilic backbone and hydrophobic side chains or vice versa. A typical example is a random copolymer of acrylic acid and a fatty alkyl acrylate. Cteniform deflocculants have been described in a large number of patents, for example WO-A-9106622.
A more effective type of deflocculant has surfactant rather than cteniform architecture. With a hydrophilic polymer group attached at one end to a hydrophobic group. Such deflocculants are typically telomers formed by telomerising a hydrophilic monomer with a hydrophobic telogen. Examples of surfactant deflocculants include alkyl thiol polyacrylates and alkyl polyglycosides. Surfactant deflocculants are described in more details in EP O 623 670.
A disadvantage of both surfactant and cteniform deflocculants is that the concentration required to deflocculate to the extent required for optimum viscosity is critical within fairly narrow limits and varies with temperature. Either too much or too little deflocculant causes instability and/or excessive viscosity. As a result the deflocculated systems tend to separate or congeal if the temperature varies significantly. In particular, separation of a clear bottom layer is often observed on storage.
One approach to the problem of temperature stability has been to add highly cross linked polyacrylates (see U.S. Pat. No. 5,602,092). These, however, are difficult to disperse in the structured liquid.
Structured surfactants have been applied to the problems of suspending: water insoluble or sparingly soluble builders in laundry detergent; antifoams and enzymes in laundry detergents and other surfactant systems; abrasives in hard surface cleaners; pesticides and oils in agrochemical preparations; rock cuttings in drilling muds; dyestuffs in dyebath concentrates and printing inks; talcs, oils and other cosmetic ingredients in personal care formulations.
We have now discovered that a substantially non-cross linked polymer having a hydrophilic backbone and sufficient short (e.g. C1 to 5) side chains to enhance physical entanglement of the polymer molecules has the ability to stabilise deflocculated structured surfactant systems, but is more soluble and easier to disperse than the cross linked polymers used hitherto.
Our invention provides a structured surfactant composition capable of suspending solids which comprises surfactant water and, if required, electrolyte in relative proportions adapted to form a flocculated, dispersed lamellar and/or spherulitic structured surfactant system, and, in addition, sufficient of a deflocculant to inhibit the flocculation of said system characterised in that said composition comprises an effective amount of an auxiliary stabiliser which is a substantially non-cross linked, water-soluble copolymer having a hydrophilic backbone and sufficient C2-6 hydrophobic organic side chains to permit entanglement of the polymer chain. For convenience as used herein xe2x80x9cside chainxe2x80x9d includes cyclic side chains such as a benzene, cyclohexane or cyclopentane ring, attached to the hydrophilic backbone.
The auxiliary stabiliser may be a copolymer of (a) one or more unsaturated carboxylic or dicarboxylic acids having from 3 to 6 carbon atoms and/or vinyl alcohol with (b) styrene and/or a C1 to 5 alkyl ester of a C3 to 6 unsaturated carboxylic or dicarboxylic acid and/or a vinyl alcohol ester of a C2 to 6 carboxylic acid wherein the mole ratio of (a):(b) is from 0.01 to 10, preferably more than 0.1, especially more than 0.2, e.g. more than 0.5, but preferably less than 8, especially less than 5, e.g. less than 2. The polymer is substantially non-cross linked by which is meant that it comprises less than 0.05% cross lining and/or insufficient cross linking to provide pseudo plastic behaviour. Preferably the auxiliary stabiliser gives the formulation a Sisko Index of 0.1 to 0.4, e.g. 0.2 to 3.
The polymer is preferably present in an amount of from 0.01 to 10% by weight of the composition e.g. 0.05 to 5%, especially 0.1 to 2%, e.g. 0.5 to 1.5% by weight.
The polymer may preferably be a copolymer of acrylic acid with for example ethyl, propyl or butyl acrylate and/or styrene. Alternatively, a copolymer comprising vinyl alcohol and vinyl acetate propionate or butyrate residues could be used. Other mononomers include maleic acid, fumaric acid, citraconic acid, aconitic acid, itaconic acid, crotonic acid, isocrotonic acid, angelic acid and tiglic acid and their esters or partial esters. The effectiveness of the auxiliary stabiliser may be enhanced by the presence of a clay such as bentonite. The latter, however, is not normally sufficient to stabilise the composition in the absence of the polymer. Particularly preferred are water dispersible synthetic layered silicates such as that sold by Laporte under its Registered Trade Mark xe2x80x9cLAPONITExe2x80x9d.
It has been found that clays and, in particular, synthetic layered silicates are synergistic with the copolymeric auxiliary stabilisers. This provides a further aspect of the invention. The clay is generally used in amounts between 0.01 and 10% by weight of the composition. Typically using clays such as bentonite, proportions of from 0.1 to 8% may be used, more usually 0.5 to 5%, e.g. 1 to 3%. However, synthetic layered silicates are effective in substantially lower concentrations e.g. 0.01 to 2%, e.g. 0.05 to 1%, especially 0.1 to 0.5% by weight. Use of the clay or silicate permits the proportion of copolymer to be substantially reduced, e.g. 0.01 to 0.5% by weight based on the weight of the composition.
The invention therefore provides, according to a further embodiment an auxiliary stabiliser for deflocculated structured surfactants which comprises from 10 to 90% by weight of a copolymer having a hydrophilic backbone and C2 to 6 hydrophobic side chains, with from 90 to 10% by weight of a natural or synthetic clay.
The deflocculant may be a surfactant deflocculant including any of those referred to in EP O 623 670. Particularly preferred are the alkyl thiol polycarboxylate telomers such as a C8-20 alkyl thiol polyacrylate or polymaleate and alkyl polyglycosides such as C8-20 alkyl polyglucoside e.g. having a D.P. greater than 1.2, preferably greater than 1.5. Alternatively the stabiliser may be a cteniform polymer of the type described in WO-A-9106622. The deflocculant is typically present in the amount required to deflocculate the system. This depends on the nature of the surfactant and of the deflocculant but is typically in the range 1 to 5% although higher concentrations may be required in some cases.
Compositions according to the present invention generally contain at least sufficient surfactant to form a structured system. For some surfactants this may be as low as 2% by weight, but more usually requires at least 3%, especially at least 4%, typically more than 5% by weight of surfactant.
Detergent compositions of the present invention preferably contain at least 10% by weight of total surfactant (including the deflocculant, where the latter is a surfactant) based on the total weight of the composition. Most preferably the total surfactant is at least 20%, especially more than 25%, e.g. more than 30% by weight of the composition. It is unlikely in practice that the surfactant concentration will exceed 80% based on the weight of the composition and is usually less than 70% especially less than 60%, typically less than 50% e.g. less than 40% by weight of the composition.
The amount of surfactant present in the composition is preferably greater than the minimum which is able, in the presence of a sufficient quantity of surfactant-desolubilising electrolyte, to form a stable, solids-suspending structured surfactant system.
The surfactant may comprise anionic, cationic, non-ionic, amphoteric semi polar and/or zwitterionic species or mixtures thereof.
Anionic surfactant may comprise a C10-20 alkyl benzene sulphonate or an alkyl ether sulphate which is preferably the product obtained by ethoxylating a natural fatty or synthetic C10-20 e.g. a C12-14 alcohol with from 1 to 20, preferably 2 to 10 e.g. 3 to 4 ethyleneoxy groups, optionally stripping any unreacted alcohol, reacting the ethoxylated product with a sulphating agent and neutralising the resulting alkyl ether sulphuric acid with a base. The term also includes alkyl glyceryl sulphates, and random or block copolymerised alkyl ethoxy/propoxy sulphates.
The anionic surfactant may also comprise, for example, C10-20 e.g. C12-18 alkyl sulphate.
The surfactant may comprise a C8-20 e.g. C10-18 aliphatic soap. The soap may be saturated or unsaturated, straight or branched chain.
Preferred examples include dodecanoates, myristates, stearates, oleates, linoleates, linolenates and palmitates and coconut and tallow soaps. Where foam control is a significant factor we particularly prefer to include soaps e.g. ethanolamine soaps and especially monothanolamine soaps, which have been found to give particularly good cold storage and laundering properties.
The surfactant may include other anionic surfactants, such as olefin sulphonates, paraffin sulphonates, taurides, isethionates, ether sulphonates, ether carboxylates, aliphatic ester sulphonates, e.g. alkyl glyceryl sulphonates, sulphosuccinates or sulphosuccinates. Preferably the other anionic surfactants are present in total proportion of less than 45% by weight, based on the total weight of surfactants, more preferably less than 40%, most preferably less than 30%, e.g. less than 20%.
The cation of any anionic surfactant is typically sodium but may alternatively be potassium, lithium, calcium, magnesium, ammonium, or an alkylammonium having up to 6 aliphatic carbon atoms including isopropylammonium, monoethanolammoniun, diethanolammonium, and triethanolammonium. Mixtures of the above cations may be used.
The surfactant preferably contains one, or preferably more, non-ionic surfactant. These preferably comprise alkoxylated C8-20 preferably C12-18 alcohols. The alkoxylates may be ethoxylates, propoxylates or mixed ethoxylated/propoxylated alcohols. Particularly preferred are ethoxylates with 2 to 20 especially 2.5 to 15 ethyleneoxy groups.
The alcohol may be fatty alcohol or synthetic e.g. branched chain alcohol. Preferably the non-ionic component has an HLB of from 6 to 16.5, especially from 7 to 16, e.g. 8 to 15.5. We particularly prefer mixtures of two or more non-ionic surfactants having a weighted mean HLB in accordance with the above values.
Other ethoxylates and/or propoxylated non-ionic surfactants which may be present include C6-16 alkylphenol alkoxylates, alkoxylated fatty acids, alkoxylated amines, alkoxylated alkanolainides and alkoxylated alkyl sorbitan and/or glyceryl esters.
Other non-ionic sufactants which may be present include amine oxides, fatty alkanolamides such as coconut monoethanolamide, and coconut diethanolamide and alkylaminoethyl fructosides and glucosides.
The proportion by weight of non-ionic surfactant is preferably at least 2% and usually more than 10%, more typically more than 20%, e.g. 30 to 75%, especially 40 to 60% based on the total weight of surfactant However compositions wherein the non-ionic surfactant is from 75 to 100% of the total weight of the surfactant are included and may be preferred for some applications.
The surfactant may be, or may comprise major or minor amounts of, amphoteric and/or cationic surfactants, for example betaines, sulphobetaines, amidobetaines, imidazolines, amidoamines, quaternary ammonium surfactants and cationic fabric conditioners having two long chain alkyl groups, such as tallow groups. Examples of fabric conditioners which may be deflocculated according to our invention include ditallowyl dimethyl ammonium salts, ditallowyl methyl benzyl ammonium salts, ditallowyl imidazolines, ditallowyl amidoamines and quaternised ditallowyl imidazolines and amidoamines. The anion of the fabric conditioner may for instance be or may comprise methosulphate, chloride, sulphate, acetate, lactate, tartrate, citrate or formate. We prefer that the compositions of our invention do not contain substantial amounts of both anionic and cationic surfactants.
We particularly prefer that the surfactant consists essentially of a mixture of a non-ionic ethoxylate with an amine oxide or, preferably an amphoteric surfactant. Such mixtures exhibit strong synergistic soil removal. The mixture may desirably contain from 1:10 to 10:1 weight ratio of non-ionic to amphoteric e.g. 1:5 to 5:1.
A major advantage of the preferred compositions of the invention is their ability to suspend solid particles to provide non-sedimenting pourable suspension. Optionally the composition may contain up to, for example, 80% by weight, based on the weight of the composition, of suspended solids, more usually up to 30 e.g. 10 to 25%. The amount will depend on the nature and intended use of the composition. For example in detergent compositions it is often desired to include insoluble builder such as zeolite or sparingly soluble builders such as sodium tripolyphosphate which may be suspended in the structured surfactant medium.
The surfactant systems according to our invention may also be used to suspend abrasives such as talc, silica, calcite or coarse zeolite to give hard surface cleaners; or pesticides, to provide water dispersible, pourable compositions containing water insoluble pesticides, without the hazards of toxic dust or environmentally harmful solvents. They are useful in providing suspensions of pigments, dyes, pharmaceuticals, biocides, or as drilling muds, containing suspended shale and/or weighting agents such as sodium chloride, calcite, barite, galena or haematite.
They may be used to suspend exfoliants including talc, clays, polymer beads, sawdust, silica, seeds, ground nutshells or dicalcium phosphate, pearlisers such as mica, glycerol mono- or di-stearate or ethylene glycol mono- or di-stearate, natural oils, including mineral and glyceride oils such as coconut, evening primrose, groundnut, meadow foam, apricot kernel, avocado, peach kernel or jojoba oils, essential oils, synthetic oils such as silicone oils, vitamins, anti dandruff agents such as zinc omadine, and selenium disulphide, proteins, emollients such as lanolin or isopropylmyristate, waxes and sunscreens such as titanium dioxide and zinc oxide.
We prefer that detergent compositions of our invention contain dissolved builder and/or suspended particles of solid builder, to provide a fully built liquid detergent xe2x80x9cBuilderxe2x80x9d is used herein to mean a compound which assists the washing action of a surfactant by ameliorating the effects of dissolved calcium and/or magnesium. Generally builders also help maintain the alkalinity of wash liquor. Typical builders include sequestrants and complexants such as sodium tripolyphosphate, potassium pyrophosphate, trisodium phosphate, sodium ethylene diamine tetracetate, sodium citrate or sodium nitrilo-triacetate, ion exchangers such as zeolites and precipitants such as sodium or potassium carbonate and such other alkalis as sodium silicate. Said stabiliser also contributes to the total builder. The preferred builders are zeolite and sodium tripolyphosphate. The builder may typically be present in concentrations up to 50% by weight of the composition e.g. 15 to 30%.
The pH of a composition for laundry use is preferably alkaline, as measure after dilution with water to give a solution containing 1% by weight of the composition, e.g. 7 to 12, more preferably 8 to 12, most preferably 9 to 11.
Compositions of our invention may optionally contain small amounts of hydrotropes such as sodium xylene sulphonate, sodium toluene sulphonate or sodium cumene sulphonate, e.g. in concentrations up to 5% by weight based on the total weight of the composition, preferably not more than 2%, e.g. 0.1 to 1%. Hydrotropes tend to break surfactant structure and it is therefore important not to use excessive amounts. They are primarily useful for lowering the viscosity of the formulation, but too much may render the formulation unstable.
The compositions may contain solvents, in addition to water. However, like hydrotropes, solvents tend to break surfactant structure. Moreover, again like hydrotropes, they add to the cost of the formulation without substantially improving the washing performance. They are moreover undesirable on environmental grounds and the invention is of particular value in providing solvent-free compositions. We therefore prefer that they contain less than 6%, more preferably less than 5%, most preferably less than 3%, especially less than 2%, more especially less than 1%, e.g. less than 0.5% by weight of solvents such as water miscible alcohols or glycols, based on the total weight of the composition. We prefer that the composition should essentially be solvent-free, although small amounts of glycerol and propylene glycol are sometimes desired. Concentrations of up lo about 3% by weight, e.g. 1 to 2% by weigh of ethanol are sometimes required to enhance perfume. Such concentrations can often be tolerated without destabilising the system.
Compositions of our invention may contain various polymers. In particular it is possible to incorporate useful amounts of polyelectrolytes such as uncapped polyacrylates or polymaleates. Such polymers may be useful because they tend to lower viscosity and because they have a detergent building effect and may have anticorrosive or antiscaling activity. Unfortunately they also tend to break surfactant structure and cannot normally be included in structured surfactants in significant amounts without destabilizing the system. We have discovered that relatively high levels of polyclectrolytes can be added to structured detergents in conjunction with deflocculated polymers and auxiliary stabilisers of the invention without destabilising the structure. This can provide stable products of even lower viscosity than can be achieved with the deflocculant and auxiliary stabiliser alone.
Some examples of polymers which may be included in the formulation are antiredeposition agents such as sodium carboxymethyl cellulose, antifoams such as silicone antifoams, enzyme stabilisers such as polyvinyl alcohols and polyvinyl pyrrolidone, dispersants such as lignin sulphonates and encapsulents such as gums and resins. We have found that milling aids such as sodium dimethylnapthalene sulphonate/formaldehyde condensates are useful where the solid suspended in the composition requires milling as in the case of dye or pesticide formulations.
The amount of polymer added depends on the purpose for which it is used. In some cases it may be as little as 0.01% by weight, or even lower. More usually it is in the range of 0.1 to 10%, especially 0.2 to 5%, e.g. 0.5 to 2% by weight.
The solid suspending detergent compositions of our invention may comprise conventional detergent additives such as antiredeposition agents (typically sodium carboxymethyl cellulose), optical brighteners, sequestrants, antifoams, enzymes, enzyme stabilisers, preservatives, dyes, pigments, perfumes, fabric conditions, e.g. cationic fabric softeners or bentonite, opacifiers, bleach activators and/or chemically compatible bleaches. We have found that peroxygen bleaches such as sodium perborate, especially bleaches that have been protect e.g. by encapsulation, are more stable to decomposition in formulations according to our invention than in conventional liquid detergents. Generally all conventional detergent additives which are dispersible in the detergent composition as solid particles or liquid droplets, in excess of their solubility in the detergent, and which are not chemically reactive therewith may be suspended in the composition.
In addition to providing novel laundry detergents, fabric conditioners and scouring creams the stabilised structured surfactants of our invention may be used in toiletries, including shampoos,liquid soaps, creams, lotions, balms, ointments, antiseptics, dentifrices and styptics.
They provide valuable suspending media for dye and pigment concentrates and printing inks, pesticide concentrates and drilling muds. In the presence of dense dissolved electrolytes such as calcium bromide they are particularly useful for oilfield packing fluids (used to fill the gap between the pipe and the inside of the borehole, to protect the former from mechanical stresses) and completion fluids in oil well, or as cutting fluids or lubricants.
The invention will be illustrated by the following examples.


A grain spreading device that uses a pre-spreading device within a cone shaped guide to provide uniform distribution of grain. Specifically, the pre-spreading device has an opening therein such that a distance between the opening and the outer periphery of the pre-spreading device forms a shelf to direct grain toward the opening to provide a uniform distribution of the grain. Additionally, the pre-spreading device can have laser cut knockouts to adjust the pre-spreading device to a plurality of different spreading devices.

This invention is directed toward a pre-spread device for a grain spreader and more particularly to a pre-spread ring that results in a more uniform spread pattern.
Grain spreaders are well known in the art. As examples, U.S. Pat. Nos. 3,902,610 and 3,966,124 to Sukup, incorporated by reference herein in their entirety, disclose conventional grain spreaders. To enhance the spread pattern of a grain spreader, it is desirable to distribute or drop the grain toward the center of the spreader since a transport auger generally drops grain toward one side of the spreader. Presently, to assist in distributing grain toward the center of the grain spreader a pre-spread funnel is mounted to the top of the spreader. While the funnel assists in distributing grain toward the center, there are deficiencies that can be improved on in the art. For one, the funnels are expensive to manufacture and add to the cost of the spreader. Also, the attachment of the funnel is generally not secured to the spreader and on occasion the funnel can either fall or blow off. In addition, because the funnel sometimes is mounted to the top of the spreader, the funnel extends beyond the opening of the bin and the bin lid cannot be closed. Finally, because the funnel is spaced apart from the spreader pan, the distribution of the grain is not optimized.
Therefore, an object of the present invention is to provide a pre-spread device that is easier and less costly to manufacture.
A further object of the present invention is to provide a pre-spread device that optimizes the uniform distribution pattern of grain from a grain spreader.
A still further object of the present invention is to provide a pre-spreading device that is more securely attached and does not interfere with the lid of a bin.
These and other objectives will be apparent to one of skill in the art based on the following disclosure.


A rotary cutting device or element (20) includes a base or support housing (30) with a centrally arranged fastening region (32) adapted to operatively connect with an associated drive (24) that rotates the element (20) about a first rotational axis (44). The support housing (30) further includes an outer edge or periphery (50) disposed away from the centrally arranged fastening region (32). At least one cutting tool (22), including a proximate end (52), is selectively attachable to the support housing (30) at the outer edge or periphery (50) thereof. Preferably, a spring biased retaining member (72) is engaged with the proximate end (52) of the cutting tool (22) to thereby secure the same to the support housing (30).

The present invention relates to the horticultural and/or lawn care arts. It is especially relevant to the selective cutting, trimming, or removal of unwanted weeds, overgrown grasses, and other vegetation or plants. It finds particular application in connection with power trimmers or weed whackers, and will be described with particular reference thereto. However, it is to be appreciated that the present invention is also amenable to other like applications which employ a rotary cutting tool or device, e.g., lawn mowers, brush choppers and other landscaping and gardening equipment.
In the horticultural and/or lawn maintenance fields, a wide range of power-driven equipment for cutting or trimming unwanted growth is employed. For large area cutting such as for mowing lawns or fields, equipment such as, riding mowers, push or self-driven power mowers, brush choppers and the like, are commonly employed. This type of equipment is often wheel based such that it supported by and rolls across the area to be cut. It typically includes one or more rotating cutting tools (e.g., a sharpened blade of steel, or another hard metal) powered by a combustion engine, an electric motor, or another type of drive. The rotating cutting tool in much of this type of equipment is position at a selected height substantially horizontal to the surface of the area being cut. As the equipment traverses the area, e.g., on its wheels, the underlying grass or other vegetation is cut at a uniform height corresponding to the separation of the rotating cutting tool from the ground.
One piece of equipment, which is typically a hand-held and/or hand-operated power-driven cutting or trimming device, is known in the art as a power trimmer or weed whacker. Power trimmers are commonly used for selectively cutting or trimming unwanted vegetation in places or regions unsuited and/or inhospitable to the aforementioned large area cutting equipment, e.g., at lawn edges; near garden beds; around fences, trees or other obstacles; in tight or confined areas where larger equipment will not readily fit; in other areas where artificial fixtures or plants such as flowers or vegetables are desirably left unscathed; on uneven or heavily sloped terrain which is difficult to negotiated by equipment which rests on the ground; etc. In a typical embodiment, a weed whacker includes an elongated shaft having a handle or other grip disposed at a first end, and a rotary cutting element or device disposed at an opposite cutting end. A drive, such as a combustion engine, an electric motor or otherwise, is often arranged on the weed whacker to power the rotating cutting element via a drive shaft or other linkage.
In operation, a user holds the weed whacker by the handle or grip end (i.e., the operating end) and guides the cutting end into the overgrown grass, weeds, or other unwanted plant growth which is to be trimmed or cut. In a typical embodiment, the rotating cutting element includes a cutting tool which rotates rapidly under the influence of the operating motor and which strikes and cuts the targeted plant stems, branches, leaves, etc., in a rapid cutting motion which minimizes damage to the remaining uncut portion of the targeted plant. Optionally, the operating end also includes a trigger or other switch for selectively engaging the rotary cutting device or element, a throttle lever for controlling engine speed, and similar or other operating controls.
In some known power trimmer or weed whacker embodiments, the cutting tool is a blade made of steel or other hard material which is integrally attached to the rotating cutting element and radially extends outward therefrom. A blade has advantages in cutting strength and in durability. However, the blade edge wears down over time. When the blade edge becomes sufficiently dulled, it has to be re-sharpened or replaced. Due to its integral construction, replacement typically involves a replacement of the entire rotating cutting element or device. Sharpening also typically involves removal of the whole rotary cutting element. In either case, the detachment can involve tools such as a wrench which may not be readily available in the field. Detachment of the rotating cutting element can also be complicated by corrosion of the bolt or other fastener which secures it to the trimmer, e.g., due to extended exposure of the rotating cutting element to moisture and other contaminants. In any event, the removal of the entire rotary cutting device can be an inefficient and disadvantageously time consuming process. For commercial users especially, in addition to being a bother, the time expended in such efforts is lost time with respect to getting jobs completed. With heavy use, this lost time can add up quickly. Additionally, the xe2x80x9cin servicexe2x80x9d to xe2x80x9cdown timexe2x80x9d ratio for the trimmer is disadvantageously impacted to the extent maintenance time is increased by such inefficiencies.
Blade damage can be accelerated by inadvertent impacts with rocks, tree trunks, and other hard object. Such impacts can cause a catastrophic blade fracture or other failure. Because the cutting end is manually guided, such impacts are to be expected at least occasionally. The difficulty and expense in re-sharpening or replacing the blade typically dictates using a very hard, durable blade material such as steel. However, although any manually guided rotating cutting element presents a safety hazard, a rigidly attached steel blade can be especially dangerous. The steel blade is relatively inflexible and cannot bend around or flex to avoid or lessen the full impact with objects inadvertently struck. The inflexibility combined with the blade hardness tends to result in substantial injury or damage to the struck object or the blade.
In part, to avoid some of the aforementioned difficulties, in other known weed whacker embodiments the cutting tool is a length of nylon string or similarly tough but flexible material connected to the rotary cutting element. Under rapid rotation, an end of the nylon string is drawn radially out and away from the axis of rotation by centrifugal force to form an elongated whip suitable for the cutting tasks. In a typical arrangement, the rotating cutting element includes a reel of nylon thread which is selectively unreeled, e.g., in a stepped fashion, to provide a controlled length for cutting and/or replace length as the nylon thread disintegrates or otherwise shortens due to wear.
Flexible elongated elements such as nylon thread can bend around or flex to avoid or lessen the impact with an object, and can therefore be safer than a rigidly attached inflexible blade. However, the highly abrasive cutting can quickly disintegrate the comparatively soft nylon string, requiring inconvenient repeated operation of the unreeling mechanism to maintain a usable length. When all the string on the reel is used up, it typically has to be replaced. Hence, the same disadvantages previously described with respect to the integral blade cutting tool are encountered. Both the unreeling mechanism and the reel replacement can be complicated by grass clippings and other contaminants which can jam up the unreeling mechanism. Furthermore, the bending and flexing of the flexible string which beneficially improves safety also substantially limits cutting strength, so that nylon string weed whackers are usually limited in application to light duty cutting tasks. Further, the nylon string can tend to be come tangled which in turn demands further maintenance.
The present invention contemplates a new and improved rotary cutting device with quick-release blades and/or an associated method that overcomes the above-mentioned limitations and others.
In accordance with one embodiment of the present invention, a rotary cutting device is provided. The rotary cutting device includes base having: a coupling region adapted for connection of the base with an associated drive that rotates the base; a slot at a periphery of the base; and, a hollow shaft in communication with the slot. A retaining member arranged in the hollow shaft is movable between a first position wherein the retaining member intersects the slot and a second position wherein the retaining member does not intersect the slot. A cutting tool has a proximate end and a cutting region extending therefrom. The proximate end is arranged to be received in the slot and has an opening arranged to receive the retaining member therethrough when the retaining member is in the first position.
In accordance with another embodiment of the present invention, a horticultural apparatus includes a drive and a base operatively connected to the drive for selective rotation thereby. The base has a peripheral opening, and a cutting tool having a proximate end is received into the peripheral opening. A retaining member is arranged in the base. The retaining member is movable between a first position in which the retaining member is engaged with the cutting tool to secure the cutting tool to the base and a second position in which the retaining member is disengaged from the cutting tool to release the cutting tool from the base.
In accordance with yet another embodiment of the present invention, a rotary cutting element is provided to which a cutting tool is selectively secured. The rotary cutting element has a centrally arranged fastening region adapted to operatively connect with a drive that rotates the rotary cutting element, and a periphery having a slot adapted to receive an end the cutting tool. A recess is in communication with the slot, and a retaining member arranged in the recess. The retaining member is slidable between a first position wherein the retaining member intersect the slot and a second position wherein the retaining member does not intersect the slot. A spring biases the retaining member toward the first position.
One advantage of the present invention resides in the capability to provide for quick and easy cutting tool attachment to and/or detachment from a rotary cutting device or element.
Another advantage of the present invention resides in the capability to remove and/or secure cutting tools to a rotary cutting device in the field without resort to tools such as a wrench or the like.
Yet another advantage of the present invention resides in the capability to lower the down time for horticultural equipment by increasing the ease and speed at which cutting tool maintenance and/or replacement can be carried out.
Numerous additional advantages and benefits of the present invention will become apparent to those of ordinary skill in the art upon reading and understanding the following detailed description.

Rotary cutting device with quick-release blades


Equipment and a process for upgrading oil are provided to produce a refined oil lighter than a material oil by cracking the heavier material oil with the addition of hydrogen under relatively relaxed production conditions. An equipment for upgrading oil according to one aspect of the invention includes an emulsion making portion (10), a refinery tank portion (20), and a heating portion (30), and configured to make an emulsion (E) by emulsifying ionized alkaline water (A) in a material oil (O1) in the emulsion making portion (10), and to drop droplets (D) of the emulsion (E) onto the surface (S) of a heat medium (O2) in the refinery tank portion (20) heated by the heating portion (30).

1. Field of the Invention
The present invention relates to equipment and process for upgrading oil to enable production of a lighter refined oil from a heavier material oil.
2. Description of the Related Art
There is a trend toward lighter products in worldwide oil situations in recent years. So-called light oils (light hydrocarbon oils), such as a gasoline, a heating oil, and a gas oil, can be obtained not only by means of distillation of oil, such as atmospheric distillation and vacuum distillation, but also by cracking so-called heavy oils (heavy hydrocarbon oils). The process of obtaining a light oil from a heavy oil includes catalytic cracking by which a heavy oil is cracked using a catalyst, hydro-cracking by which a heavy oil is cracked using a catalyst in a hydrogen gas stream with the addition of hydrogen, thermal cracking by which a heavy oil is thermally cracked without using a catalyst, and so forth (see, for example, Japanese Unexamined Patent Publication No. 07-011259 and Japanese Unexamined Patent Publication No. 09-183983).
In addition to the need for a catalyst, catalytic cracking and hydro-cracking require regeneration processing of the catalyst because the catalyst becomes inactive with catalytic cracking of a heavy oil. Further, hydro-cracking requires strict production conditions at a temperature of 500° C. or above and a pressure of 30 to 100 atmospheres. Thermal cracking also requires strict production conditions at a temperature of 400° C. to 500° C. and a pressure of 2 to 30 atmospheres.