Thermoplastic molding compositions comprising, as substantive constituents,

The invention relates to thermoplastic molding compositions comprising, as substantive constituents,
A) from 5 to 96% by weight of a vinylaromatic polymer with a syndiotactic structure,
B) from 2 to 50% by weight of an inorganic filler,
C) from 1 to 15% by weight of a thermoplastic elastomer based on copolymers made from vinylaromatic monomers, dienes and, where appropriate, 1,1-diphenylethylene,
D) from 1 to 10% by weight of a compatibilizer, and, where appropriate,
E) from 1 to 15% by weight of an elastomeric particulate styrene-diene block copolymer whose diene content may have been completely or to some extent hydrogenated, and, where appropriate,
F) additives,
where the total of the percentages by weight of A) to F) is 100.
The invention further relates to the use of the thermoplastic molding compositions for producing fibers, films or moldings, and also to the resultant fibers, films or moldings.
Due to its crystallinity, syndiotactic polystyrene has a very high melting point of about 270xc2x0 C., high stiffness and tensile strength, dimensional stability, a low dielectric constant and high chemicals resistance. Its mechanical property profile is even retained at temperatures above its glass transition temperature. The preparation of syndiotactic polystyrene in the presence of metallocene catalyst systems is known and described in detail in EP-A 0 535 582, for example.
The field of application of syndiotactic polystyrene is severely restricted by its brittleness.
There has therefore been a desire to reduce the brittleness of syndiotactic polystyrene, also termed SPS below, while at the same time improving its impact strength, breaking stress and stiffness.
EP-A 0 779 329 (Idemitzu Kosan) and WO-A 94/24 206 (Dow) have disclosed polymer blends made from syndiotactic polystyrene, from inorganic fillers, from polyphenylene ether and from a rubber component. However, the properties of the blends are still unsatisfactory, for example low flowability and complicated preparation.
EP-A 755 972 describes SPS which has been impact-modified using a mixture of, on the one hand, a block copolymer made from styrene and from hydrogenated butadiene and, on the other hand, a core-shell polymer with a butadiene polymer core. Molding compositions with inorganic fillers are not disclosed.
It is an object of the present invention, therefore, to prepare a thermoplastic molding composition which is based on vinylaromatic polymers with a syndiotactic structure and which combines high impact strength, high stiffness (modulus of elasticity), and good flowability (MVR, processability) and breaking stress.
We have found that this object is achieved by means of the thermoplastic molding compositions defined at the outset.
The use of the thermoplastic molding compositions for producing fibers, films or moldings has also been found, as have the resultant fibers, films and moldings.
As component A), the thermoplastic molding compositions of the invention comprise from 5 to 96% by weight, preferably from 20 to 80% by weight, in particular from 40 to 70% by weight, of a vinylaromatic polymer with a syndiotactic structure. The expression xe2x80x9cwith a syndiotactic structurexe2x80x9d means for the purposes of the present invention that the polymers are substantively syndiotactic, i.e. the syndiotactic content determined by 13C NMR is above 50%, preferably above 60%, of mmmm pentads.
Component A) has preferably been built up from compounds of the formula I
where:
R1 is hydrogen or C1- to C4-alkyl, and
R2 to R6 independently of one another, are hydrogen, C1- to C12-alkyl, C6- to C18-aryl, or halogen, or where two adjacent radicals together are a cyclic group having from 4 to 15 carbon atoms, such as C4-C8-cycloalkyl, or anellated ring systems.
It is preferable to use vinylaromatic compounds of the formula I where
R1 is hydrogen.
Particular substituents R2 to R6 which may be used are hydrogen, C1- to C4-alkyl, chlorine, phenyl, biphenyl, naphthalene or anthracene. Two adjacent radicals together may also be a cyclic group having from 4 to 12 carbon atoms, examples of resultant compounds of the formula I being naphthalene derivatives or anthracene derivatives.
Examples of these preferred compounds are:
Styrene, p-methylstyrene, p-chlorostyrene, 2,4-dimethylstyrene, 4-vinylbiphenyl, vinylnaphthalene and vinylanthracene.
It is also possible to use mixtures of various vinylaromatic compounds, but it is preferable to use just one vinylaromatic compound.
Particularly preferred vinylaromatic compounds are styrene and p-methylstyrene.
Mixtures of various vinylaromatic polymers with a syndiotactic structure may also be used as component A), but it is preferable to use just one vinylaromatic polymer, in particular syndiotactic polystyrene (SPS).
Vinylaromatic polymers (A) with a syndiotactic structure and processes for their preparation are known per se and are described in EP-A 535 582, for example. The preferred method of preparation is to react compounds of the general formula I in the presence of a metallocene complex and of a cocatalyst. Particular metallocene complexes used are pentamethylcyclopentadienyltitanium trichloride, pentamethylcyclopentadienyltrimethyltitanium, and pentamethylcyclopentadienyltitanium trimethylate.
The vinylaromatic polymers with a syndiotactic structure generally have a molar mass Mw (weight-average) of from 5000 to 10,000,000 g/mol, in particular from 10,000 to 2,000,000 g/mol. The polydispersities Mw/Mn are generally from 1.1 to 30, preferably from 1.4 to 10.
Other vinylaromatic polymers which may be used as component A) and have a syndiotactic structure are syndiotactic star polymers based on vinylaromatic monomers. Examples of these star polymers are described in the earlier German patent application 196 34 375.5-44, in particular on page 2, line 21 to page 6, line 25, and in the examples.
As component B), the molding compositions of the invention comprise from 2 to 50% by weight, preferably from 5 to 45% by weight, in particular from 15 to 42% by weight, of fibrous or particulate inorganic fillers, or mixtures of these.
Examples of these are carbon fibers, glass fibers, glass mats, glass silk rovings or glass beads, or else potassium titanate whiskers, preferably glass fibers. Glass fibers may have been provided with a size or with a coupling agent. These glass fibers may be incorporated either as short glass fibers or else as continuous-filament strands (rovings). Preferred glass fibers comprise an aminosilane size and typically have a diameter D of from 1 to 30 xcexcm, preferably from 3 to 20 xcexcm, in particular from 5 to 15 xcexcm. In the extruded molding compositions of the invention these glass fibers then have a length-to-diameter ratio of from 5 to 100, preferably from 10 to 80, in particular from 15 to 50.
Examples of materials which may be used as component B) are amorphous silica, magnesium carbonate, powdered quartz, mica, talc, feldspat or calcium silicates.
As component C), the thermoplastic molding compositions of the invention comprise from 1 to 15% by weight, preferably from 1 to 10% by weight, of copolymers made from vinylaromatic monomers and from dienes and, where appropriate, 1,1-diphenylethylene. This component C) may also be termed a thermoplastic elastomer (TPE).
Component C) is preferably prepared by anionic polymerization.
Particularly preferred components C) are three-block copolymers, particularly those which have been hydrogenated. The copolymers used as component C) are preferably those prepared from styrene, 1,1-diphenylethylene and butadiene, in particular styrene (S)/1,1-diphenylethylene (DPE)-butadiene-S/DPE three-block copolymers, the butadiene block having been hydrogenated (EB), i.e. (S/DPE)-EB-(S/DPE).
Other suitable copolymers or block copolymers have at least one block A made from vinylaromatic monomers a1) and 1,1-diphenylethylene or its derivatives a2) with substitution of the aromatic rings where appropriate by alkyl groups having up to 22 carbon atoms, obtainable by anionic polymerization, the copolymer or the block A having been formed by using an initiating solution composed of the product from reaction of an anionic polymerization initiator with at least the equimolar amount of monomers a2).
It is preferable to prepare block copolymers having at least one block A and having at least one, where appropriate hydrogenated, block B made from dienes b), using sequential anionic polymerization, by carrying out the following steps in succession:
I) Forming a block A by
I.1) Preparing an initiating solution composed of the product from the reaction of an anionic polymerization initiator with at least the equimolar amount of monomers a2),
I.2) Adding any remaining amount of monomers a2) and from 60 to 100% of the total amount of monomers a1),
I.3) Adding any remaining amount of monomers a1) when the conversion of the monomers added in the preceding steps has reached at least 80%,
the concentration of the polymerization solution after the final addition of monomers being at least 35% by weight,
II) and then forming a block B by
II.1) Adding an additive which affects the polymerization parameters, and
II.2) Adding the dienes b), and where appropriate, carrying out the following steps:
III) Adding a chain terminator or coupling agent,
IV) Hydrogenating the block copolymer,
V) Isolating and working-up the block copolymers in a manner known per se, and
VI) Adding stabilizers.
The copolymers or the blocks A are composed of vinylaromatic monomers a1) and 1,1-diphenylethylene or its derivatives a2) substituted on the aromatic rings where appropriate with alkyl groups having up to 22 carbon atoms, preferably having from 1 to 4 carbon atoms, such as methyl, ethyl, isopropyl, n-propyl or n-, iso- or tert-butyl. Preferred vinylaromatic monomers a1) are styrene and its derivatives substituted at the a position or on the aromatic ring with 1 to 4 carbon atoms, for example xcex1-methylstyrene, p-methylstyrene, ethylstyrene, tert-butylstyrene or vinyltoluene. Unsubstituted 1,1-diphenylethylene itself is particularly preferably used as monomer a2). The molar ratio of the units which derive from 1,1-diphenylethylene or its derivatives a2) to units which derive from the vinylaromatic monomer a1) is generally from 1:1 to 1:25, preferably from 1:1.05 to 1:10, and particularly preferably from 1:1.1 to 1:3.
The copolymers or the blocks A preferably have a random structure, and their molecular weight Mw is generally from 1,000 to 500,000, preferably from 3,000 to 100,000, particularly preferably from 4,000 to 30,000.
In principle any diene is suitable as diene b) for the block B, but preference is given to those having conjugated double bonds, for example 1,3-butadiene, isoprene, 2,3-dimethylbutadiene, 1,3-pentadiene, 1,3-hexadiene, phenylbutadiene, piperylene and mixtures of these. Particular preference is given to the use of 1,3-butadiene or isoprene. The diene block may have been partially or completely hydrogenated, or be unhydrogenated. The hydrogenation of polyisoprene blocks gives ethylene-propylene blocks, and that of polybutadiene blocks gives polyethylene blocks or polyethylene-butylene blocks as determined by the 1,2-vinyl content of the unhyrogenated butadiene blocks. The hydrogenation makes the block copolymers more thermally stable and especially more resistant to ageing and to weathering. The molecular weights Mw of the blocks B is generally from 10,000 to 500,000, preferably from 20,000 to 350,000, and particularly preferably from 20,000 to 200,000. The glass transition temperatures of the blocks B are generally below xe2x88x9230xc2x0 C., preferably below xe2x88x9250xc2x0 C.
The proportion by weight of the total of all of the blocks A, based on the entire block copolymer, is generally from 5 to 95% by weight, preferably from 5 to 50% by weight, particularly preferably from 25 to 35% by weight.
The anionic polymerization is initiated using organometallic compounds. The initiators used may be the usual alkali metal alkyl compounds or alkali metal aryl compounds. It is advantageous to use organolithium compounds, such as ethyl-, propyl-, isopropyl-, n-butyl-, sec-butyl-, tert-butyl-, phenyl-, hexylbiphenyl-, hexamethylenedi-, butadienyl-, isoprenyl- or polystyryllithium. Particular preference is given to the use of 1,1-diphenylhexyllithium, which is easily obtainable from the reaction of 1,1-diphenylethylene with n- or sec-butyllithium. The amount of initiator needed is calculated from the desired molecular weight and is generally from 0.002 to 5 molpercent, based on the amount of monomer to be polymerized.
Suitable solvents are solvents inert toward the organometallic initiator. It is advantageous to use aliphatic, cycloaliphatic or aromatic hydrocarbons having from 4 to 12 carbon atoms, such as pentane, hexane, heptane, cyclopentane, cyclohexane, methylcyclohexane, decalin, isooctane, benzene, alkylbenzenes, such as toluene, xylene or ethylbenzene, or suitable mixtures.
Once the build-up of molecular weight has ended, the xe2x80x9clivingxe2x80x9d ends of the polymer may, if desired, be reacted with conventional chain terminators or with conventional coupling agents, the amounts of which usually depend on the amount of initiator used.
Suitable chain terminators are protonating substances or Lewis acids, such as water, alcohols, aliphatic or aromatic carboxylic acids, or else inorganic acids, such as carbonic acid, phosphoric acid or boric acid.
For coupling of the block copolymers, use may be made of bi- or polyfunctional compounds, for example halides of aliphatic or araliphatic hydrocarbons, such as 1,2-dibromoethane, bischloromethylbenzene, or silicon tetrachloride, dialkyl- or diarylsilicon dichloride, alkyl- or arylsilicon trichloride, tin tetrachloride, polyfunctional aldehydes, such as terephthalic dialdehyde, ketones, esters, anhydrides or epoxides. If the block copolymer is not being hydrogenated, preferred coupling agents used are carboxylic esters, such as ethyl acetate. For hydrogenated block copolymers, it is preferable to use 1,2-dibromoethane or diepoxides, in particular diglycidyl ethers, such as 1,4-butanediol diglycidyl ether.
Examples of an additive (randomizer) used which affects polymerization parameters are Lewis bases, such as polar, aprotic solvents, and metal salts soluble in hydrocarbons. Examples of Lewis bases which may be used are dimethyl ether, diethyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, tetrahydrofuran, tetrahydrofurfuryl ethers, such as tetrahydrofurfuryl methyl ether, and tertiary amines, such as pyridine, trimethylamine, triethylamine and tributylamine, and peralkylated di- or oligoamines, such as tetramethylethylenediamine. These are usually used at concentrations of from 0.1 to 5 percent by volume, based on the solvent. Among the metal salts soluble in hydrocarbons, it is preferable to use the alkali metal or alkaline earth metal salts of primary, secondary, or especially tertiary alcohols, particularly preferably the potassium salts, such as potassium triethylcarbinolate or potassium tetrahydrolinaloolate. The molar ratio of metal salt to initiator is usually from 1:5 to 1:200, preferably from 1:30 to 1:100.
The selection of the randomizer and its amount depends on the desired final product. For polymers not intended for hydrogenation and if, for example, when using butadiene, a high 1,4-vinyl content is desired, it is preferable to use a potassium salt soluble in hydrocarbons. For polymers which are intended for subsequent hydrogenation it is preferable to use tetrahydrofuran. The amount used here is preferably such that if butadiene is used, for example, the resultant 1,2-vinyl-content is from about 20 to 50%.
In this process the entire amount of the monomers a2) preferably forms an initial charge in a solvent and is mixed with the polymerization initiator. However, it is also possible for some part of the monomers a2) or of the solvent not to be added until later. The amount of polymerization initiator is calculated by taking the amount calculated from the desired molecular weight and from the total amount of monomer to be polymerized, and adding an amount calculated from any protic contaminants which may be present in monomers or solvent, and which may be removed by filtration to an endpoint. It is preferable to use n- or sec-butyllithium, which reacts completely with the monomers a2) within a few hours, generally from 0.5 to 40 hours at from 20 to 70xc2x0 C., to give 1,1-diphenylhexyllithium or, respectively, the corresponding substituted derivatives. The temperature of the initial charge is preferably controlled at from 40 to 70xc2x0 C. while from 60 to 100%, preferably from 70 to 90%, of the entire amount of monomers a1) needed to form the block A is fed. The feed time depends on the reactivity of the monomers used and on the concentration, and is generally from 0.5 to 10 hours and from 40 to 70xc2x0 C. The addition of the remaining amount of the monomers a1) generally takes place after conversion has exceeded 80%, preferably has exceeded 95%, of the monomers which form the initial charge or have been added by that time. Block A is polymerized at high monomer concentration, and it is possible here to achieve a reduction in the amount of residual monomers a2). The concentration of the polymerization solution after the final addition of monomer is generally at least 35% by weight, particularly preferably more than 50% by weight.
In preparing the block copolymers with at least one block B, a block A is first formed as described above, followed by a block B, by sequential anionic polymerization.
After formation of the A block and prior to addition of the dienes b), the additive which affects the polymerization parameters is added to the polymerization solution. The block B is then polymerized by adding the dienes b). Prior to or during the addition of the diene it is advisable to dilute the reaction mixture with an inert solvent, in order to ensure sufficient mixing and heat dissipation. The polymerization temperature for the block B is preferably from 50 to 90xc2x0 C., and when using polar, aprotic solvents as randomizer it is particularly preferably from 50 to 70xc2x0 C.
The resultant A-B block copolymers may be terminated by chain terminators or coupling agents or, in the case of bifunctional coupling agents, linked to give linear three-block copolymers, or in the case of higher-functionality coupling agents, linked to give star-shape block copolymers.
The process is not restricted to solution polymerization. For example, the process can also readily be applied to dispersion polymerization. For this, it is advantageous to use a dispersion medium which is inert toward the anionic polymerization initiators and in which the A block is insoluble, for example, propane, butane, isobutane, pentane or its branched isomers, hexane, heptane, octane or isooctane. In order to obtain a small particle size, from 0.1 to 2% by weight of a dispersing agent is generally added. Examples of suitable dispersing agents are styrene/butadiene two-block copolymers with the highest possible molar mass, for example above 100,000 g/mol.
Other suitable components C) are thermoplastic elastomers such as styrene-butadiene-styrene, for example as described in WO-A 97/40079 (BASF), and Styroflex(copyright) BX 6105 from BASF, for example.
As component D), the thermoplastic molding compositions of the invention comprise from 1 to 10% by weight, preferably from 1 to 8% by weight, in particular from 1.2 to 5% by weight, of a compatibilizer which as far as is known at present brings about the coupling to the inorganic filler B). Substances known from the literature may be used, in particular polyarylene ethers.
Polyarylene ethers, and also processes for their preparation, are known per se and are described in DE-A 42 19 438, for example. Among the polyarylene ethers, polyphenylene ethers are particularly suitable, especially polyphenylene ethers modified with polar groups. These polyphenylene ethers modified with polar groups, and also processes for their preparation, are also known per se and are described in DE-A 41 29 499, for example.
The compounds preferably used as component D) are polyphenylene ethers modified with polar groups and built up from
d1) from 70 to 99.95% by weight of a polyphenylene ether,
d2) from 0 to 25% by weight of a vinylaromatic polymer, and
d3) from 0.05 to 5% by weight of at least one compound which contains at least one double or triple bond and at least one functional group selected from the class consisting of carboxylic acids, carboxylic esters, carboxylic anhydrides, carboxamides, epoxides, oxazolines and urethanes.
Examples of polyphenylene ethers d1) are
poly(2,6-dilauryl-1,4-phenylene) ether,
poly(2,6-diphenyl-1,4-phenylene) ether,
poly(2,6-dimethoxy-1,4-phenylene) ether,
poly(2,6-diethoxy-1,4-phenylene) ether,
poly(2-methoxy-6-ethoxy-1,4-phenylene) ether,
poly(2-ethyl-6-stearyloxy-1,4-phenylene) ether,
poly(2,6-dichloro-1,4-phenylene) ether,
poly(2-methyl-6-phenyl-1,4-phenylene) ether,
poly(2,6-dibenzyl-1,4-phenylene) ether,
poly(2-ethoxy-1,4-phenylene) ether, poly(2-chloro-1,4-phenylene) ether, and poly(2,5-dibromo-1,4-phenylene) ether.
It is preferable to use polyphenylene ethers whose substituents are alkyl radicals having from 1 to 4 carbon atoms, for example
poly(2,6-dimethyl-1,4-phenylene) ether,
poly(2,6-diethyl-1,4-phenylene) ether,
poly(2-methyl-6-ethyl-1,4-phenylene) ether,
poly(2-methyl-6-propyl-1,4-phenylene) ether,
poly(2,6-dipropyl-1,4-phenylene) ether and
poly(2-ethyl-6-propyl-1,4-phenylene) ether.
Examples of preferred vinylaromatic polymers c2) can be found in the monograph by Olabisi, pp. 224 to 230 and 245. Merely as examples, mention may be made here of vinylaromatic polymers made from styrene, chlorostyrene, xcex1-methylstyrene or p-methylstyrene. Subordinate amounts (preferably not more than 20% by weight, in particular not more than 8% by weight, of comonomers, such as (meth)acrylonitrile or (meth)acrylates, may also be involved in the structure. Particularly preferred vinylaromatic polymers are polystyrene and impact-modified polystyrene. It is, of course, also possible to use a mixture of these polymers. The preparation process is preferably that described in EP-A 302 485.
Examples of suitable modifiers d3) are maleic acid, methylmaleic acid, itaconic acid, tetrahydrophthalic acid, anhydrides and imides thereof, fumaric acid, the mono- and diesters of these acids, e.g. of C1- and C2- to C8-alkanols, the mono- and diamides of these acids, such as N-phenylmaleimide and maleic hydrazide. Other examples which may be mentioned are N-vinylpyrrolidone and (meth)acryloylcaprolactam.
The elastomeric component E) made from a styrene-diene block copolymer whose diene content may have been to some extent or completely hydrogenated is known, for example from EP-A 755 972, and is commercially available, for example as Kraton(copyright) G 1651 from Shell. Other examples are Cariflex(copyright)-TR grades (Shell), Finaprene(copyright) grades (Fina) and Europrene(copyright) grades (Enichem).
The usual amounts of additives or processing aids or mixtures of these may be added to the thermoplastic molding compositions of the invention.
Examples of these are nucleating agents, such as salts of carboxylic, organic sulfonic, or phosphoric acids, preferably sodium benzoate, aluminum tris(p-tert-butylbenzoate), aluminum trisbenzoate, aluminum tris(p-carboxymethylbenzoate), and aluminum triscaproate; antioxidants, such as phenolic antioxidants, phosphites or phosphonites, in particular trisnonylphenyl phosphite; stabilizers, such as sterically hindered phenols and hydroquinones. Use may also be made of lubricants, mold-release agents, dyes, pigments and plasticizers.
Organophosphorus compounds, such as phosphates or phosphine oxides, may be used as flame retardants.
Examples of phosphine oxides are triphenylphosphine oxide, tritolylphosphine oxide, trisnonylphenylphosphine oxide, tricyclohexylphosphine oxide, tris(n-butyl)phosphine oxide, tris(n-hexyl)phosphine oxide, tris(n-octyl)phosphine oxide, tris(cyanoethyl)phosphine oxide, benzylbis(cyclohexyl)phosphine oxide, benzylbisphenylphosphine oxide, and phenylbis(n-hexyl)phosphine oxide. Particular preference is given to the use of triphenylphosphine oxide, tricyclohexylphosphine oxide, tris(n-octyl)phosphine oxide or tris(cyanoethyl)phosphine oxide.
Phosphates which may be used are especially alkyl- and aryl-substituted phosphates. Examples of these are phenyl bisdodecyl phosphate, phenyl bisneopentyl phosphate, phenyl ethyl hydrogenphosphate, phenyl bis(3,5,5-trimethylhexyl) phosphate, ethyl diphenyl phosphate, bis(2-ethylhexyl) p-tolyl phosphate, tritolyl phosphate, trixylyl phosphate, trimesityl phosphate, bis(2-ethylhexyl) phenyl phosphate, tris(nonylphenyl) phosphate, bis(dodecyl) p-(tolyl) phosphate, tricresyl phosphate, triphenyl phosphate, dibutyl phenyl phosphate, p-tolyl bis(2,5,5-trimethylhexyl) phosphate, and 2-ethylhexyl diphenyl phosphate. Particularly suitable phosphorus compounds are those where each R is aryl. Very particularly suitable compounds here are triphenyl phosphate, trixylyl phosphate and trimesityl phosphate. It is also possible to use cyclic phosphates. Among these, diphenyl pentaerythritol diphosphate is particularly suitable. Preference is also given to resorcinol diphosphate.
It is also possible to use mixtures of various phosphorus compounds.
The total of components A) to F) is 100%.
The thermoplastic molding compositions of the invention may be obtained by mixing the individual components, generally at from 270 to 330xc2x0 C. in conventional mixing equipment, such as kneaders, Banbury mixers or single-screw extruders, preferably using a twin-screw extruder. To obtain a homogeneous molding composition, intensive mixing is needed. The sequence in which the components are blended may be varied, for example two or, if desired, more components may be premixed, but it is also possible for all of the components to be mixed together.
The thermoplastic molding compositions of the invention may also be blended with other polymers, such as atactic or isotactic homopolystyrene, styrene copolymers with, for example acrylonitrile, methacrylates and/or diphenylethylene as comonomers, or with polyamides, polyesters or polyphenylene ethers, or mixtures of the polymers, generally as described above.
The thermoplastic molding compositions of the invention have high impact strength, high stiffness and good flowability (processability). They are suitable for producing fibers, films or moldings.

Impact resistant thermoplastic molding materials comprised of syndiotactic polystyrene, glass fibers and thermoplastic elastomer (tpe) impact modifiers


A method and apparatus for the production of ligneous material boards characterized by a positive separation of the press platen applying the compression pressure from the mat at the frame sealing the outer margin, so that the press pressure is applied independently of the pressure required for the sealing.

The invention relates to a method for the production of boards of ligneous material and to a steam press for the practice of the method.
In a known method according to EP 0 339 952 a preliminary compression is at first applied to the mat of raw material and steam is introduced into the press chamber alternately from the top down and from the bottom up. This has the advantage that the heating of the mat by the transfer of heat from the steam to the mat material takes place rapidly and the cycling time can be reduced by as much as 75%. Sealing from the atmosphere is provided by a frame which is tightly anchored to the margin of the upper press platen. Two pressure bars of different thickness, 6 and 12 mm, are used for the frame. In the case of a changeover of production, the frame is replaced. This procedure takes about two days, and in addition to installation personnel it requires that the press be shut down with the attendant loss of production, since the frame is composed of several bars. The force applied by the piston-and-cylinder system is divided into a force acting on the actual mat of raw material and a force acting on the material under the sealing bars. Assuming that a uniform depth of material is applied over the entire width of the press, a higher pressure on the material is established under the sealing bars. As the state of compression advances, the ratio of force Fpressure bar to Fchipboard shifts toward ever increasing values. This effect can be seen in exponential compression curves (layer depth over press pressure).
The disadvantages of a geometrically and permanently anchored frame on the press platen are:
During the preliminary compression of the actual raw material mat to establish a permeability suitable for the mass flow of the steam, a certain material density is established under the bar by the compression curve, according to the height of the bar selected, to seal it off from the atmosphere, but depending on the steam pressure it may not be sufficient to prevent the leakage of steam; in other words, the material density under the pressure bars might not suffice to prevent the escape of steam from the press area.
During the main compression, the actual board is to be brought down to the desired thickness. The force applied by the main cylinder is here again divided between the force on the pressure bars and the force on the platen.
Due to the pressure which increases exponentially as compression increases, the pressure under the pressure bars increases considerably more than it does on the actual product. For this reason, for the production of greater final board thicknesses it is essential to change the pressure bars to different thicknesses. The press pressure on the board itself is limited, the pressure under the pressure bars increases rapidly, and this can also lead to material damages at the upper and lower press platen. When the press is opened, the ligneous material board still has an elevated temperature level and the residual water contained in the board evaporates. The raising of the upper press platen is simultaneous with the raising of the pressure bar and the expansion steam escapes to the sides. This results in considerable soiling of the steam press, especially the cylinder surfaces. To avoid blowouts in the board, before raising the upper press platen a relief period of about one minute must be observed. This steam expansion process can be abbreviated in some cases by the use of a vacuum.
The lateral escape of the expanded steam is a disadvantage, because it leads to considerable soiling of the steam press as well as its surroundings, and long expansion periods are necessary before the steam press is opened so as to prevent blowouts.
The invention is addressed to the problem of devising a method in which the escape of steam from the press space is prevented in every phase of the compression of the mat, in which no damage or contamination of the steam press occurs, and in which the described disadvantages do not appear, and also the problem of creating a steam press for the practice of the method.
The solution of this problem includes a separation of the press platen applying the pressure from the frame sealing the mat at its outer margin, so that the press pressure is applied independently of the pressure necessary for the edge sealing.
A steam press for the practice of the method of the invention is characterized by the fact that the frame is configured as a sealing frame in contact with the lateral walls of the moving press platen, can be raised and lowered thereon by actuators, and grips the mat at its outer margin, and that the sealing frame can be controlled as to pressure, time and motion, independently of the application of pressure to the moving press platen.
The separation of the actual pressing surface and sealing frame by hydraulic actuators for control of stroke and pressure independent of the press movement results in the advantage that the press pressure on the mat can be optimized through the entire processing time as required. The sealing pressure is independent of the press pressure and can be kept constant or adapted to requirements throughout the pressing period, independently of the actual board thickness.
In the preliminary compression phase the preliminary pressure on the platen can be variable, that is to say, it can be adjusted regardless of the preliminary compression under the sealing frame. An optimum setting of the permeability of the mat can be established by optimizing the sealing pressure and material density under the sealing frame. This sealing pressure can be sustained throughout the process.
In the main compression, a defined and measurable pressure on the mat can be established as required. Due to the defined pressure conditions uncontrolled mechanical deformation or destruction of the steam press can no longer occur.
Before the press is opened, the upper press platen can be set for a compression pressure of from xe2x89xa64 N/mm2 to an expansion or steam relief pressure of 0.5 N/mm2, while the sealing frame can be held down on the compressed board. The expansion or steam relief pressure is equal to or greater than the transverse tensile strength in the press platen corresponding to the glue setting that has taken place up to this moment of the pressing process. The expanding steam can then be relieved into the space between the board and the upper press platen and be carried out through the nozzles. The expansion counter-pressure of the upper press platen is controlled over a distance/pressure gradient of from xe2x89xa70.5 N/mm2 toward 0 N/mm2. After that, the press is opened. It is especially advantageous that the expansion steam can no longer escape laterally and thus contamination of the press and its surroundings can be prevented by the controlled removal of the steam. Also, blowouts in the middle and cover layers are prevented, and the formerly necessary steam relief period of one minute has been saved, without the need to use the vacuum systems of the former state of the art.
Additional advantages of the invention are protection of the equipment by the sealing provided by the controlled sealing frame at all board thicknesses, reduction of the steaming time by controlling permeability and thus increasing the throughput, shortening of the steam escape period which can be further optimized by adapting the distance/pressure control gradients of the upper press platen to larger steam carrying cross sections, the loss of production and elimination of the need for personnel for product changes (changing the pressure bars) because a flying or automated change has become possible, production of LDF (low-density fiberboard) with a density lower than 500 kg/m3 on account of the independently controllable pressure and distances between the upper press platen and the sealing frame, optimization of the pressing process for MDF (medium-density fiberboard), the use of higher steam pressures ( greater than 16 bar) is possible resulting in a reduction of the consumption of industrial binding agent by activating the lignin contained in wood as adhesive, and creation of defined and desired pressure conditions on the platen and the sealing frame in every phase of the production process.
To let off the expanding steam using the pressure gradient from  greater than 0.5 N/mm2 to 0 N/mm2, the cross sections of the steam-bearing lines in the upper and lower press platens and their feed lines and removal lines as well as the control valves can be adapted to the greater volume of the diminishing steam pressure as well as the short expansion periods best for the process.

Method and steam press for the production of boards of ligneous material

Maschinenfabrik J. Dieffenbacher GmbH and Co.


A traffic speed control and surveillance system includes a speed sensor, vehicle identifier and transmitter/receiver disposed in a motor vehicle. The system also includes a plurality of mini remote terminal units disposed along a highway for monitoring signals from passing motor vehicles. Those signals identify the vehicle and speeds of those vehicles. The system also includes a communication center and one or more master remote terminal units for linking the mini remote terminal units to the communication center which processes the information. The communication center may also transmit a signal to disable the engine of an offending vehicle.

This invention relates to a traffic speed and control system for motor vehicles and more particularly to an improved traffic speed and control system that records and reports speed limit violations and alerts patrol cars of vehicles being driven at an excessive rate of speed and their location.
Traffic surveillance and control systems for motor vehicles are well known. For example, U.S. Pat. No. 3,680,043 of Angeloni discloses a system for monitoring the speed of highway vehicles from a central control station. The system includes posting devices positioned at intervals along the highway and adapted to receive a speed message from the control station and transmit the speed message to passing vehicles in a limited region of the highway in the form of an r-f signal. Each vehicle contains an r-f receiver which is connected to the vehicle speedometer or other vehicle identification means in a manner that will provide, upon the occurrence of some predetermined excessive speed, an indication to the driver of the vehicle that the speed limit at that particular region of the highway is being exceeded. There is also a provision for reporting back to the control station the occurrence of an excessive vehicular speed as well as for providing accident warnings and the like.
A more recent approach to traffic speed surveillance systems is disclosed in U.S. Pat. No. 4,591,823 of Horvat. As disclosed therein, the system includes a set of monitored transceivers located along a roadway and communicating with a central processor. The system also includes stationary transceivers for sending radio signals indicative of the speed limit in the location of a particular stationary transceiver. A vehicle transceiver mounted in a vehicle includes means for entering driver identification, vehicle identification and speedometer means for measuring the speed of the vehicle. The vehicle transceiver receives the radio signals from the monitored transceiver indicative of speed limit and compares measured speed against the limit and sends radio signals indicative of drive identification, vehicle identification and speed limit violation to the monitored transceiver for reporting to the central processor.
A further and even more recent approach to traffic surveillance systems is disclosed in U.S. Pat. No. 5,952,941 of Mardirossian. As disclosed therein, a satellite traffic control system determines the location, and upon which roadway a vehicle is traveling. A memory in the vehicle system stores speed limit data relating to different roads, speed limits and/or red lights across the globe. A controller in the vehicle compares speed limit data, relative to determined speed of the vehicle so as to detect when the speed limit on the road upon which the vehicle is traveling is exceeded. When the speed limit is exceeded, a transmitter on the vehicle transmits a signal to at least one satellite indicative of the violation. The satellite forwards the violation signal to a motor vehicle department so that a ticket can be issued to the vehicle operator. In a similar manner, the satellite base system can detect other infractions such as running of red lights, and issue tickets in response to the same.
The traffic surveillance systems described above have not received broad commercial success. Accordingly, it is presently believed that there may be a need for an improved traffic surveillance system in accordance with the present invention. It is also believed that there may be a commercial market for an improved traffic surveillance system which offers numerous advantages. For example, it is presently believed that the implementation of the system disclosed herein will save lives, reduce injuries and property damage due to traffic accidents. As a result, there should be a corresponding reduction in hospital expenses and insurance claims which should further reduce the cost of accident and health insurance.
The system disclosed herein should also reduce aggressive driving techniques and aid in accident investigations. In addition, the systems will improve road safety for drivers and pedestrians, and should reduce the cost of enforcing speed limits and allow patrol vehicles and officers to concentrate on more serious offenses and/or provide assistance to drivers and others in need of help. Further, the systems disclosed herein should generate more revenue by an automated ticket function. The system also provides a remote system for disabling a vehicle which is being operated at a speed in excess of a given rate or in the case of an emergency to disable all vehicles in a given area with the exception of emergency vehicles.
In essence, the present invention contemplates an improved traffic speed surveillance and control system for regulating the speed of motor vehicles in selected areas. The traffic speed surveillance and control system includes a speed sensing means and vehicle identification means, both disposed within a motor vehicle as well as a vehicle mounted transmitter/receiver means which is operatively connected to the speed sensing means. The vehicle mounted transmitter/receiver means, transmits radio signals which are indicative of the vehicle identification and speed in a given location.
A plurality of speed monitoring mini remote terminal units are located along a highway. Each of those units includes location identification means and a first remote transmitter/receiver means for receiving signals from a vehicle mounted transmitter/receiver means which is indicative of the speed and identification of a passing vehicle. Each of the speed monitoring mini remote terminal units include computer means, a programable speed limit programmed into the computer, location identifying means and means for comparing the speed limit and the speed of a passing vehicle.
The traffic speed surveillance and control system also includes a communication center and one or more master remote terminal units receiving signals from a plurality of speed monitoring mini remote terminal units. The remote terminal units transmit data indicative of vehicle speed in excess of speed limits, vehicle identification and location from the mini remote terminal units to the communication center.
The communication center includes means for processing the information from the master remote terminal unit as for example to print a traffic citation for forwarding to the vehicle owner or to a patrol car for stopping the vehicle. Also, when the speed exceeds a predetermined speed over the speed limit, the communication center can transmit a signal to disable the engine in the offending vehicles or in the event of an emergency, to disable all of the motor vehicle engines in the area other than emergency vehicles wherein the vehicles include means to override the engine disabling function.
Each of the plurality of mini remote terminal units also includes means for generating a signal indicative of vehicle passing speed and identification when the vehicle speed exceeds the programmed speed limit.
The invention will now be described in connection with the accompanying drawings wherein like reference numerals have been used to identify like parts.

Traffic speed surveillance and control system

Al-Riqqa, Block 7, 4th St., House #(1) - 218


A building and construction material and method of making the material utilizes water with cement which are mixed together and followed by mixing with a mineral filler material such as sand or gravel to produce concrete having micropores of about 0.01 to about 5.mu. in diameter. By eliminating from the mineral filler material all fine grains of less than 0.2 mm, it has been found that the strength of the concrete is improved and the amount of shrinkage is reduced.

The present invention relates to a building and construction material consisting substantially of binding agents such as cement, and mineral filler materials, a method of producing the building and construction material and a method of reducing the degree of shrinkage in the building and construction material.
The present invention is a further development of European Patent Application EP 0 647 603 which is equivalent to U.S. Pat. No. 5,641,815 and in which a construction and building material, such as concrete is disclosed which includes uniformly dispersed micropores. These superfine pores have a diameter in the range of about 0.01.mu. to about 5.mu., whereby the individual pores are themselves closed.
In this way, it is possible to build structures and building parts with a substantial higher strength in comparison with common concrete. The pores include an amount of air which is conventionally included in concrete for anti-freezing effect but the concrete is stronger than conventional concrete.
The micropores are obtained by mixing the binding agent or reactive material, such as cement, with additives, such as tensides and water in a conventional mixer or in a high turbulence mixer, in order to be thereafter or directly mixed in one processing step in a conventional concrete mixer with the aggregate such as sand and gravel. In case no additives are used, a high turbulence mixer must be used. In case additives such as tensides are used, the mixing of the cement with water can proceed in a conventional mixer.
The inclusion of micropores finds specific application for the production of so called lightweight building materials, such as those containing lightweight filler materials, in that due to the increase of the strength of the concrete enclosing the filler materials, the finally resulting lightweight building material has a sufficient strength.

Building material having low degrees of shrinkage


Aerogel particles having a mean particle size less than 1 micron, products containing the same, processes of making the same, and uses thereof are described. A process of making the particle is also described wherein starting aerogel particles are homogenized or wet milled. The starting aerogel particles can be surface treated during the milling process to prevent agglomeration or aggregation. The aerogel particles can be used in a variety of products and applications.

The present invention relates to aerogel particles, products containing the same, processes of making the same, and uses thereof.
Aerogel particles can have a very low density, high porosity, and small pore diameters. They can be extremely light weight and are usually formed by replacing the particles in a gel with a gas. Aerogel particles have a wide range of uses. For example, aerogels, in particular those with porosities of greater than about 60% and densities of less than about 0.4 g/cc, can exhibit very low thermal conductivity. Therefore, aerogels are used as thermal insulating materials as described, for example, in EP-A-0 171 722, incorporated in its entirety by reference herein. A class of aerogels includes silica gel particles. Silica gel materials are used in a wide variety of applications including matting agents, catalysts, personal care products, and chromatography to name a few.
Commercially produced silica gel materials can typically have large surface areas and void volumes and have narrow pore size distributions in the mesopore and micropore ranges. The lower limit of the particle size distribution of these materials is typically more than 3 microns which can be achieved by air jet milling of the dried silica gel powder. Thus, current processes do not permit the production of smaller particles, thereby limiting the use of silica gels or aerogels.
There is also a need to provide a tighter particle distribution range that can lead to better quality control of the finished product since each batch of material preferably has more similar physical properties.
Accordingly, there is a need for particles that avoid one or more of the above-described disadvantages.

Aerogel particles and methods of making same


An improved composition and method for plaque inhibiting hard candies, is disclosed, having alkali metal monophosphate as the improved neutralizing active ingredient.

1. Field of the Invention
The invention relates to a hard candy with tooth plaque-neutralizing effect, the use of a hard candy to clean the teeth, and a process and device for manufacturing a hard candy. The term hard candy is generally understood to mean oval compressed lozenges, chewable candies, pastilles capsules, tablets, and similar presentations.
2. Background of the Prior Art
After the consumption of food and stimulants, tooth plaque is a particular risk, due to the resulting acids. In particular, sugars cause and promote dental caries, and it is currently considered to be scientifically proven that carious lesions are the result of a process that affects the surface of teeth. The fermentation of orally administered carbohydrates into organic acids, in bacterial tooth plaque, and the related drop in the pH of that plaque are of primary importance for the formation of caries.
To neutralize tooth plaque acids, alkaline compounds, such as sodium carbonate, bicarbonate, and ammonium phosphate, as well as ureas, have been recommended to counter the organic acids that are formed by the fermentation of carbohydrates. However, the salts and sometimes bitter taste of those buffers has made it difficult to use them. For example, EP-525 388 describes the manufacture and composition of a tablet having the aim of producing a slight foaming action to improve the taste of tablets containing active pharmaceutical ingredients, particularly calcium and magnesium. U.S. Pat. No. 4,409,202 describes a tablet or candy whose aim is to cover or neutralize mouth odor. The main active ingredient is a vegetable oil. U.S. Pat. No. 5,250,569 proposes the use of amino acids, including in connection with toothpastes, to avoid the unpleasant taste of orally-administered aluminum compounds. It would then be possible to produce special rhinitis medications containing aluminum. Another aim of that US patent is to produce a slow-release effect for aluminum. Finally, JP-A-69 13281 suggests the manufacture of tablets to clean the mouth and deodorize the breath.
The most effective mechanical method of inhibiting caries is to clean the teeth with toothpaste and a toothbrush after every occasion on which stimulants or food are consumed. However, it is not always possible to clean the teeth with toothpaste and a brush after every meal or every time food is consumed. That is particularly the case when away from home, traveling, at work, and the like.
Against that background, so-called plaque-neutralizing chewing gums have been offered as an alternative for some time. They are intended both to stimulate the flow of saliva, as a result of chewing movements, and to contain the aforementioned active ingredients, which cause a buffer action in the saliva, or result in neutralization of the acids produced during the fermentation of carbohydrates. Those chewing gums have the advantage that they can be used immediately after eating and, to a great extent, can neutralize the acids that damage the teeth. That may be done, by stimulating the flow of saliva, whereby an increased buffer capacity is produced; by promoting the neutralization of plaque acids; by increasing the distribution of saliva in difficult to reach interdental spaces; by improved removal of food particles from the oral cavity; by creating a pH value that promotes remineralization of the tooth enamel; or finally, by promoting remineralization via stimulating the flow of saliva with an increased mineral content.
Such chewing gums are also useful, for example, for patients with temporary or chronically limited mobility, which generally leads to poorer oral hygiene. In addition, when taking medications that inhibit the flow of saliva, the aforementioned chewing gum can be a useful tool for improving oral hygiene.
However, the problem with such plaque-neutralizing chewing gums is that gum chewing is socially unacceptable to many people, or is rejected for other reasons, for example in the presence of dental prostheses, synthetic teeth, and the like. Therefore, one aim of the present invention is to create an alternative to chewing gum that increases neutralization of acid plaque, thereby preventing or at least inhibiting formation of caries in the presence of plaque.
Hard candy with plaque-neutralizing effect that contain at least one active ingredient that neutralizes acid to a great extent, have been considered in the past for a number of reasons. A principle desired advantage of the hard candy is that the problems described in connection with chewing gums are eliminated. For example, it is known that when chewing gum, the active ingredients are released by strong chewing during the first 1.9 minutes, but very few of the effective neutralizing substances are released by the chewing gum after 2.0 minutes, which retards the neutralizing effect. In contrast, a hard candy that would better distribute the dose of neutralizing active ingredient, could last up to 5-6 minutes. Moreover, the stimulation of saliva flow should be nearly identical to that when chewing gum is used. Also, JP-A-60237947 discloses a special encapsulated air bubble appearance for candy in order to promote a refreshing perceived effect.
The prior art active ingredients for hard candies have been alkaline metal salts, and alkaline earth metal salts, in particular polyphosphates, carbonates, hydrocarbonates, and hydrogen phosphates. However these prior art candy formulations have several drawbacks in so far as their use of phosphate is concerned.
In the past Mr. Austin Wagenknicht disclosed the use of a restricted class of phosphates, in U.S. Pat. No. 4,170,632, for plaque inhibiting hard candies. However, the types of phosphates used were the same as those formulated for chewing gums, i.e., polyphosphates including pyrophosphates, orthophosphates, tripolyphosplates and hexametaphosphates in amounts of at least 1% by weight, and preferably 2% to about 20%. In addition, it was disclosed that dental abrasives, which may be dicalcium diphosphate dihydrate, or sodium metaphosphate, or tricalcuim phospate might also be included in amounts of 1% to 30% preferably 1.5% to about 20%. In practice, the threshold amount of acid-neutralizing material was at least, that amount needed to neutralize and establish a pH of between about 5.5 to about 10 in the oral cavity, preferably pH about 6 to 9.
A plaque inhibiting active ingredients formulation, effective in hard candies, at lesser amounts than the prior art would be a welcomed but surprising advancement over chewing gum type formulations.
It is therefore a principle object of the present invention to provide improved plaque inhibiting neutralizing ingredients.
This principle object and other objects will become apparent from the following detailed description, examples and claims which are fulfilled by utilizing alkali metal monophosphates, as the active ingredient in plaque inhibiting hard candies. We have discovered that these materials, surprisingly, can be effective and at lower concentrations than the prior art polyphosphates.
In accordance with the improved composition of the present invention alkali metal monophosphates employed as the active neutralizing ingredient in plaque inhibiting hard candies. The alkali metal monophosphates are effective in amounts as low as 0.1% to less than about 1% by weight. The monophophates can be used in higher amounts also of up to 15%. Amounts of monophosphates of 1% to 2.0% by weight are more effective than similar amounts of polyphosphates. However, unlike polyphosphates which were required to be use at 1.0% or higher, the monophosphates are effective at a lower threshold amount. The alkali metal monophosphates which are particularly preferred are disodium hydrogen phosphate (sodium phosphate dibasic), potassium dihydrogen phosphate (potassium phosphate monobasic).
The active ingredients of the present invention are effective alone, or if desired can be used in combination with each other or with other plaque inhibiting neutralizing agents such as carbonates, bicarbonates (hydrocarbonates).
To cover the occasionally salty, soapy, or bitter taste of those acid-neutralizing active ingredients, sugar substitutes or sugar replacements and sweeteners are preferably added to the hard candy in accordance with the invention. In that regard, examples include isomalt, sorbitol, acesulfam, lycasine, sweeteners containing cyclamate, aspartame, etc.
Moreover, it has proven beneficial to add xylitol as an addition to the acid-neutralizing active ingredient, because xylitol also has a certain inhibiting effect on plaque formation, particularly in conjunction with the aforementioned active ingredient.
In addition to the aforementioned substances or active ingredients, the hard candies in accordance with the invention contain at least one carrier, as well as one or more taste-imparting flavoring agents, such as peppermint flavor, orange flavor, and the like.
To manufacture a hard candy in accordance with the invention, it is suggested to use a fundamentally known process for manufacturing candy, although it is suggested to select a temperature that does not exceed 135xc2x0 C., preferably 80xc2x0 C., during the metered addition of the acid-neutralizing active ingredients to the candy manufacturing mass. It has been shown in practice that in general the active substances that are essential to the invention at least partially decompose or are broken down at temperatures higher than the specified level of 135xc2x0 C.
For that reason, in accordance with the invention a device or equipment for manufacturing a hard candy is suggested that is fundamentally based on a device or equipment usually used for manufacturing hard candies. It is essential to the invention that subsequent to the cooking vessel, such as for example as cooking coil, where the various basic materials, such a as carriers, water, sugar substitutes, and the like are cooked and mixed at approximately 160xc2x0 C. and over, the mass is cooled by an additional cooler to a temperature from approximately 130-135xc2x0 C. The proposed additional cooler is generally not included in such equipment. The metered addition of the acid-neutralizing active ingredients occurs after said additional cooling, as suggested above.
The invention will now be explained in greater detail below using experiments in which the neutralizing candy, mode in accordance with the invention, was given to a series of test subjects at the Dental Institute of the University of Zurich and confirmed the neutralizing effect of the candy. The results obtained by the Dental Institute of the University of Zurich are explained in greater detail in the Examples.

Hard candy with plaque-neutralizing effect comprising alkali metal monophosphate


A bridge bidding box is provided comprising two parts: a bottom and a top part. When the box is opened, the bottom part is removed and placed into a cut out area of the top part. The cut out area of the top part is angled so that when the bottom part is placed into this cut out area, the cards in the bottom part are automatically angled backwards, making it easier to see and remove the bid cards from the box. This configuration allows the entire box to lie flat on the table, providing stability and proper weight distribution. The bottom of the box is provided with non-skid gripping material, which prevents the box from moving or sliding on the table. When the base part is placed into the top part, the top part is at an angle and weight distribution that it is difficult to tip over the box.

The present invention relates to devices used for bidding in the game of bridge.
Bridge is a partnership game with two players to each partnership. Players are given the names North, South, East and West, corresponding to points on the compass. That is, North sits opposite South, and East sits opposite West. North and South are a partnership, and East and West are a partnership. Before each hand is played, an auction is conducted to decide which suit of the four, hearts, spades, clubs, or diamonds, will be the trump suit, the cards in the trump suit having more power to win tricks than the cards in any other suit. At this time it is decided which partnership will be the defense, and which partnership will contract to win a certain number of tricks. A trick includes the play of one card from each player""s hand, and the player who plays the most powerful card wins the trick.
In the duplicate form of contract bridge, bidding boxes and convention cards are used to conduct a silent auction in order to avoid any vocal inflections that, in a verbal auction, might give one""s partner unauthorized information about the contents of one""s hand. Each hand includes 13 of the 52 cards that have been dealt from the 52 cards in the deck. Each of four players thus holds 25% of the cards in the deck. In duplicate bridge, the cards patterns, or hands, are dealt and put into a holder called a board. The board keeps each of the four hands from getting mixed up. After a certain number of hands are dealt and played, the boards, as well as the East-West pairs, move from table to table, so that the players, as well as the hands in each board, are played by different partnerships throughout the bridge session. The results, or scores, are compared at the end of the playing period, and whichever pairs has the best results, when the scores from all boards are compared, win the bridge session.
Tournament play requires the use of bidding boxes so that each player makes a bid silently by removing the appropriate bid player card from the bidding box and displaying it in an accepted manner, even if the bid made is inappropriate or in violation of existing contract bridge bidding rules.
Currently available bidding boxes are all designed to facilitate silent bidding. These devices were meant either to sit on top of the playing table or to be mounted on the side of the table.
The first previously known bidding device is the Bid Box from Germany. This is a cone piece design made of a flexible composite. The underside or bottom of the device has a lid that snaps in place, which is where the cards are stored when not in use. The cards can be removed and placed into a slotted area on the top rear of the box. The cards rest on the inside of the bottom lid so that they are maintained in an upright position. Unfortunately, the design of this box permits it to slide easily on the table, so that it can easily be knocked off, causing the cards to fly out of the box. When the box is mounted on the side of a card table, the lid must be closed properly to prevent the cards from falling out. Also, the cards may fall through the bottom if too much pressure is put on the lid when replacing the cards after bidding. The open area on top allows dirt and debris to enter the box and allows the cards to soil easily. Storing and stacking the boxes is cumbersome because of the design of the boxes. These boxes are generally made from soft plastic.
Another one-piece design is the Neo-classic from Sweden. This box works exactly like the Bid Box, but the top of the box has been rearranged so that the two slotted areas are evenly centered over the base. This modified shape make it easier to stack boxes on top of each other, but the boxes require a lot of space because of their size. The two open slots are sized differently. The front, smaller, slot holds the pass, double, re-double, alert, and stop cards. The other, larger, slot contains the bid cards. For the cards to remain upright, they must rest on the inside bottom lid. This box slides off the table easily, is big and bulky, and takes up a lot of table space. When the box is attached to the table, the cards can fall out of the bottom in the same way as with the Bid Box. The open area on top allows dirt and debris to enter the box, and allows the cards to soil easily. This box is made of a semi hard composite and is relatively durable.
The Universal Bidding Box appears to be the only two piece bidding box currently available. This box also originates in Sweden. The composite of which the box is made is thick, hard plastic, and is sturdy in design. This box takes up the smallest space on the table, and its seat design is quite unique. Cards are easy to grab, but the box, when placed on the table, is the least stable of all known biding boxes, and it can be knocked off the table quite easily. When the box is knocked over, the cards fly out onto the floor, although the box works well when bracketed to the table. This box is difficult for many people to open and close, and thus it requires directions on the top and bottom. This box is the most cumbersome for storage, principally because of its shape. The boxes do not stack at all. The boxes can be linked or snapped together, but this is impractical, so that storage is a problem. The open area in the middle of the box permits dirt and debris to enter the box and soil the card, although not to the extent as the Neo or the Bid Box.
The Pocket Style bidding box is a one-piece bidding box which is easy to use. However, it takes up too much room on the table to be useful, and it is difficult to close the unit. The cards must be repositioned when the box is opened to play and when the box is closed. The cards are difficult to reposition and are often misplaced in this box. This causes bending of some of the cards. However, the cards are totally enclosed, so that dirt and debris are prevented from entering the box and soiling the cards. Because it takes up too much room on the table, this is the least used box. However, it is easily stackable and thus uses less storage space than some of the other boxes. This box uses a composite that is both flexible, non-flexible, and thin material. The material of the which the box is made is not sturdy.
The Bridge Partner from Sweden is easy to use; the flip box is easy to open and close. When the box is flipped open, the cards are ready to use. This box is easy to stack and when installed on the side of a table it works well. Unfortunately, this box does not sit flat on the table, and it is so light that it slips and slides around on the table and is very easily knocked over. Even if a strip of gripping material is placed under the entire box, the design of the box still causes the box to be knocked over very easily, strewing the cards on the floor. The slot in the back of this box holds the alert cards; if they are not moved to the front of the box they may be crushed. The open area in the middle of the box allows dirt and debris to enter the box, soiling the cards. The cards are slightly tilted, which makes the cards easier to read than with other box designs. The box is very light.
The Trio Bidding box from Sweden is one of the most recently developed biding boxes. It is rectangular and longer than any of the other boxes described above. This is a flip box with three compartments. The small pass cards, etc., are in the front, and the suit cards are in the back of the box. The stop and alert cards lie flat in the middle. This box is easy to store and easy to open although it takes up more room than many other boxes and thus crowds the table. When the box is opened for use, it does not lie flat. When the covers of the box are opened, the box rests on the thin bottoms of the covers. This box is very light, slippery, and is easy to knock over, although it can be mounted on the side of the table. The open area in the middle of the box permits dirt and debris to enter the box to soil the cards. This box has large alert and stop cards. When opened, the front compartment has two pointed ends that stick up over the cards, making it easy to poke or hit the box with the hand, making this box vulnerable to being knocked over.
It is an object of the present invention to overcome the aforementioned deficiencies in the prior art.
It is another object of the present invention to provide a bridge bidding box which is easily opened and closed.
It is a further object of the present invention to provide a bridge bidding box in which the cards are always in place and ready to use.
It is yet another object of the present invention to provide a bridge bidding box which lies flat on a table.
It is still another object of the present invention to provide a bridge bidding box that prevents cards from falling out if the box is knocked over.
According to the present invention, a bridge bidding box is provided comprising two parts: a bottom part and a top part. When the box is opened, the bottom part is removed and placed into a cut out area of the top part. The cut out area of the top part is angled so that when the bottom part is placed into this cut out area, the cards in the bottom part are automatically angled backwards, making it easier to see and remove the bid cards form the box. This configuration allows the entire box to lie flat on the table, providing stability and proper weight distribution. The bottom of the box is provided with non-skid gripping material, which prevents the box from moving or sliding on the table. When the bottom part is placed into the top part, the top part is at such an angle and weight distribution that it is difficult to tip over the box.