Abstract: This invention provides a means to produce improved sulfur-modified chloroprene rubber for use in making products with improved heat resistance. The products of the invention require sulfurization of the chloroprene followed by plasticization. A preferred plasticizer is tetraethylthiuram.

Abstract: Nanolatexes comprising functional monomers and methods for making nanolatexes. Compositions comprising between about 3:97 and 90:10 (w/w) nanolatex particles to conventional latex particles. Because of the particle size differences between the conventional and nanolatexes, the nanolatexes may distribute themselves advantageously amongst the conventional latexes during coalescence, resulting in films having unexpected properties. In particular, when the average particle size of the conventional latex is about six times larger than the average particle size of the nanolatex, a composition comprising a ratio of 1 conventional latex particle for every 25 nanolatex particles results in unexpectedly strong (large Young's modulus) and smooth (high specular gloss) films.

Abstract: A novel process for producing a polyamidoamine-epihalohydrin resin composition comprises (a) reacting a polyamidoamine with epihalohydrin to obtain a reaction mixture comprising a polyamidoamine-epihalohydrin resin; (b) adding a first acid to the reaction mixture obtained in step (a) to obtain an acid treatment composition; (c) adding a base to the acid treatment composition in step (b) to obtain a base treatment composition; and (d) adding a second acid to the base treatment composition in step (c) to obtain a polyamidoamine-epihalohydrin resin composition; wherein the polyamidoamine-epihalohydrin resin composition obtained in step (d) has less than about 700 ppm of dihalopropanol (DHP) and 3-halopropanediol (HPD).

Abstract: The invention is directed to the use of maleic esters selected from compounds of formulae (I) and (II) as copolymerizable emulsifiers in the emulsion polymerization of olefinically unsaturated monomers, in which A is an alkyl group having 3 to 40 carbon atoms; X and Z independently are hydrogen or methyl; M is hydrogen, an alkali metal, alkaline earth metal, or an ammonium or other amine salt; and n and p independently are numbers in the range from 0 to 40.

Abstract: The UV-curable aqueous coating composition is characterized by using a UV-curable aqueous emulsion obtained by urethane reaction with a mixture including a poly-carbonate polyol or polyester polyol; an isocyanate compound; a urethane-reactive carboxylic acid; a UV-curable acrylic oligomer having 2 to 9 functional acrylate groups; a UV-curable acrylic monomer; and a urethane-reactive acrylate without an organic solvent. The aqueous composition provides good environmental acceptability and satisfactory film properties comparable to those of the prior oily UV-curable coating composition and, therefore, it is useful for coating various plastics.

Abstract: Polymer capsules from amphiphilic graft copolymers comprising reactive, hydrophobic polyolefin backbones, and hydrophilic poly(ethylene glycol) (PEG) grafts are produced by self-assembly of the polymers at the oil-water interface, and crosslinking the assembly with bis-cyclooctene PEG derivatives in conjunction with ring-open metathesis polymerization catalysts. The use of the graft copolymer architecture in capsule synthesis provides significant opportunities to tune both the surface properties, in terms of recognition, and the membrane properties, in terms of mechanical strength, encapsulation, and release.

Abstract: A coated substrate comprises a substrate and a coating on at least one surface of the substrate. The coating comprises a prepolymer, polymer, or resin produced, for example, by the reaction of (i) an isocyanate (e.g., a polyisocyanate), (ii) an active hydrogen-terminated colorant, and optionally (iii) at least one reactant selected from the group consisting of chain extenders, polyols, internal surfactants, and combinations thereof. Polymer dispersions suitable for use in making such coated substrates comprise such a prepolymer, polymer, or resin.

Abstract: Polymer capsules from amphiphilic graft copolymers comprising reactive, hydrophobic polyolefin backbones, and hydrophilic poly(ethylene glycol) (PEG) grafts are produced by self-assembly of the polymers at the oil-water interface, and crosslinking the assembly with bis-cyclooctene PEG derivatives in conjunction with ring-open metathesis polymerization catalysts. The use of the graft copolymer architecture in capsule synthesis provides significant opportunities to tune both the surface properties, in terms of recognition, and the membrane properties, in terms of mechanical strength, encapsulation, and release.

Abstract: A filler-containing an organic polymer dispersion is provided. The organic polymer of the dispersion is polymerized in the presence of particles of at least one filler. The ratio of the particle size of the filler particles to the particle size of the polymer particles is in the range of from 1.1:1 to 20:1.

Abstract: The present invention relates to a process for postcrosslinking water-absorbing polymeric particles in the absence of oxidizing gases, to the water-absorbing polymers preparable by the process and to their use in hygiene articles and packaging materials.

Abstract: Polymer capsules from amphiphilic graft copolymers comprising reactive, hydrophobic polyolefin backbones, and hydrophilic poly(ethylene glycol) (PEG) grafts are produced by self-assembly of the polymers at the oil-water interface, and crosslinking the assembly with bis-cyclooctene PEG derivatives in conjunction with ring-open metathesis polymerization catalysts. The use of the graft copolymer architecture in capsule synthesis provides significant opportunities to tune both the surface properties, in terms of recognition, and the membrane properties, in terms of mechanical strength, encapsulation, and release.

Abstract: This invention relates to waterborne coatings with enhanced early water blushing resistance, chemical resistance, and adhesion to substrates. These waterborne coatings can be paints, varnishes, and water sealers that offer excellent early water blushing as well as. excellent resistance to common household chemicals, such as gasoline, motor oil, brake fluid, transmission fluid, household cleaners, window cleaning fluids, antifreeze, and the like.

Abstract: A binder resin for an electrostatic image developing toner, obtained by polycondensation reaction of a polycarboxylic acid and a polyol, wherein the polycarboxylic acid comprises at least one of a compound represented by formula (1) and a compound represented by formula (2) in an amount of from 50 to 100 mol %, the polyol comprises a compound represented by formula (3) in an amount of from 50 to 100 mol %, and a content of a catalyst-originated metal element in the resin is 100 ppm or less: R1OOCA1mB1nA1lCOOR1???(1) (wherein A1 is a methylene group, B1 is an aromatic hydrocarbon group, R1 and R1? each is a hydrogen atom or a monovalent hydrocarbon group, 1?m+1?12, and 1?n?3); R2OOCA2pB2qA2rCOOR2???(2) (wherein A2 is a methylene group, B2 is an alicyclic hydrocarbon group, R2 and R2? each is a hydrogen atom or a monovalent hydrocarbon group, 0?p?6, 0?r?6, and 1?q?3); HOXhYjXkOH??(3) (wherein X is an alkylene oxide group, Y is a bisphenol structure group, 1?h+k?10, and 1?j?3).

Abstract: A binder resin for an electrostatic image developing toner is obtained by a polycondensation reaction of a polycarboxylic acid and a polyol, wherein the polycarboxylic acid includes a compound represented by at least one of formula (1) and formula (2) as defined in the specification in an amount of from about 50 to about 100 mol %; the polyol includes a compound represented by formula (3) as defined in the specification in an amount of from about 10 to about 100 mol %; and a content of a catalyst-originated metal element in the binder resin is about 100 ppm or less R1OOCA1mB1nA1lCOOR1???(1) R2OOCA2pB2qA2rCOOR2???(2) HOXh-Ph-Y-Ph-XkOH ??(3).

Abstract: The present invention relates to a process for preparing a resin binder for toner, comprising the steps of (A) carrying out an addition polymerization reaction of addition polymerization resin monomers including styrene in the presence or absence of an organic solvent; and (B) mixing the resulting reaction mixture from the step (A) with water at a rate of 0.002 to 0.5 parts by weight based on 100 parts by weight of the addition polymerization resin monomers per minute at a temperature of 100° to 300° C. during and/or after the step (A), wherein the amount of water to be mixed in the step (B) is 0.1 to 50 parts by weight based on 100 parts by weight of the addition polymerization resin monomers. The resin binder for a toner obtained according to the present invention can be used, for instance, for developing electrostatic latent images formed in electrophotography, electrostatic recording method, electrostatic printing method, and the like, and a toner containing the resin binder.

Abstract: Reactive polymeric surfactants are disclosed, and their use in processes for preparation of microcapsules, and in stabilising emulsions. The surfactants are random graft polymers or block copolymers which contain both hydrophobic and hydrophilic units and in which the hydrophobic unit includes a hydrophilic cross-linking unit which reacts with (a) a wall forming ingredient in a microencapsulation process, or (b) an ingredient in the disperse phase of an emulsion.

Abstract: Compositions for use in the manufacture of three-dimensional objects including compositions for use as a support and/or release material in the manufacture of the three-dimensional objects are provided. There is thus provided, in accordance with an embodiment of the present invention, a composition suitable for building a three-dimensional object. The compositions may include, inter alia, a curable component, having a functional group, wherein if the functional group is a polymerizable reactive functional group, then the functional group is a (meth)acrylic functional group, a photo-initiator, a surface-active agent and a stabilizer; wherein said composition has a first viscosity of about 50–500 cps at a first temperature, wherein said first temperature is ambient temperature, and a second viscosity lower than 20 cps at a second temperature wherein said second temperature is higher than said first temperature, wherein, after curing, the composition results in a solid form.

Abstract: An aqueous coating composition comprising a crosslinkable water-dispersible hyperbranched macromolecule(s) wherein the composition when drying has an open time of at least 20 minutes, a wet edge time of at least 10 minutes, a tack free time ?15 hours, a dust free time ?5 hours and an equilibrium viscosity of ?5,000 Pa·s at any solids content when drying in the range of from 20 to 55% by weight using any shear rate in the range of from 9±0.5 to 90±5 s?1 and at 23±2° C.

Abstract: A process for treating a composition containing a polyamine-epihalohydrin resin that has a low level of CPD-producing species and good gelation stability is disclosed. A polyamine-epihalohydrin resin is prepared with a ratio of epihalohydrin:amine of less than about 1.1:1.0; The resin is then subjected to a base treatment followed by an acid treatment resulting in a resin that has good gelation storage stability and produces low levels of CPD.

Abstract: The invention concerns a process for concentrating polymer latexes, which can be separated into a latex phase and a serum phase in a separator with the aid of an auxiliary coalescing device.

Abstract: Polyurethane or polyurethane polymer hybrid dispersions, with reduced hydrophilicity and methods for preparing and using them are disclosed.

Abstract: The present invention provides a high temperature continuous polymerization and condensation process for preparing a polymeric product. The process includes continuously charging into a reaction zone: at least one radically-polymerizable monomer having a radically polymerizable group and at least one condensation reactive functionality; and at least one modifying agent having a functional group capable of reacting with the condensation reactive functionality. The reaction zone includes at least one primary reactor, but may, and preferably does, contain a secondary reactor. The process further includes maintaining an effective temperature in the primary reactor to cause polymerization of the monomer and to allow at least a portion of the condensation reactive functionality to react with the functional group of the modifying agent.

Abstract: Coating composition and its use in a one-pot system. The coating composition comprises: an oxidatively drying polyunsaturated condensation product, such as an alkyd, having pendant groups in an amount of more than 20% by weight of the condensation product, the pendant groups comprising unsaturated CC bonds; a polythiol having two or more SH-groups; a siccative. The equivalence ratio of thiol functional groups to unsaturated CC bonds being less than 0.3, preferably between 0.01 and 0.25. The coating composition comprises 1-30 wt-%, preferably 3-20 wt-%, of thiol compounds, related to the total weight of solid resin. The coating composition further comprises a drying accelerating complexing agent, preferably 2,2′-bipyridyl or 1,10-phenantroline.

Abstract: This invention provides the composition, preparation, and end-use of waterborne crosslinking technology based compositions prepared from water-based latexes. The invention provides a water-based latex comprising dispersed, waterborne amino-functional polymer particles; dispersed, waterborne acetoacetoxy-functional polymer particles; and water. In a preferred embodiment, a latex of the invention comprises dispersed, waterborne polymeric (polyamino)enamine (PPAE) particles; dispersed, waterborne acetoacetoxy-functional polymer particles; and water. The PPAE is the reaction product of a surfactant-stabilized acetoacetoxy-functional polymer (SAAP) and a poly(alkylenimine). The water-based latexes of the invention provide stable emulsions containing a blend of waterborne polymer particles which undergo crosslinking upon film formation. The latex films or coatings may be cured at ambient temperatures or may be thermally cured.

Abstract: A composition and method that provides a chemically grafted coating onto a substrate. The composition comprises an acrylate and a grafting initiator. The acrylate may be a waterborne urethane acrylate. The composition may also comprise resistance agents, adhesion agents, UV curing photoinitators, defoaming agents, and/or deglossing agents. The substrate may be any wood or plastic, but works well with heat shrinkable polyolefin tubing. The composition may also be quick curing such that the coating from the composition may be cured under a D bulb and an H bulb at a rate of 100-160 feet/minute. The coating on the substrate resists delamination and wear. The coating may have indicia printed on the coating, the indicia being composed from ink or other printable materials.

Abstract: Process for using microwave irradiation to prepare solutions of polymers functionalized with acid groups The invention relates to a process for preparing aqueous, hydrous and anhydrous solutions of polymers functionalized with acid groups, which comprises using microwave radiation to supply the heat required to prepare the solution. The solutions are suitable as a starting material for producing gas diffusion electrodes, fuel cells and polymer-electrolyte-stabilized platinum nanoparticles.

Abstract: The present invention provides water-borne adhesives and adhesive emulsions comprising: (1) 25 to 55 weight percent of a grafted polyolefin comprising the reaction product of (i) a polyolefin, (ii) an ethylenically unsaturated monomer having functionality capable of reacting with an amino group and (iii) an amino carboxylic acid; (2) a minor amount up to 10 weight percent of a surfactant; and (3) 55 to 80 weight percent water.

Abstract: Coating composition and its use in a one-pot system.

Abstract: A water-based latex of an acrylic-modified waterborne alkyd dispersion in water is described. The acrylic-modified waterborne alkyd is a hybrid resin prepared by the polymerization of at least one ethylenically unsaturated monomer in the presence of a waterborne alkyd having at least one pendant sulfonate functionality. The ethylenically unsaturated monomer may also be a latent oxidatively functional (LOF) acrylic monomer. Preparation of the latexes may be achieved by emulsion polymerization of at least one ethylenically unsaturated monomer in the presence of a waterborne alkyd having at least one pendant sulfonate functionality. Preparation of hybrid latexes which contain latent oxidative functional (LOF) acrylic monomers may also be achieved by emulsion polymerization of at least one LOF acrylic monomer in the presence of a waterborne alkyd having at least one pendant sulfonate functionality whereby the latent oxidative functionality of the acrylic polymer survives polymerization.

Abstract: Flow improving agents for binder suspensions containing cement are described, which consist of:a) Graft polymers which have been prepared by radical grafting of a polyalkylene oxide of the general formula (I) with an ethylenically unsaturated mono- or dicarboxylic acid or the anhydride thereof, and then by derivatizing with a primary or secondary amine and/or alcohol, and also ofb) Casein.These flow improving agents have the advantage that the ability to flow is considerably improved in comparison, for example, with casein alone, and the improved ability to flow is preserved over a longer period of time.

Abstract: The present invention discloses a process for manufacturing a grafted polyacrylamide flocculant of cationic/ampholytic ions, which is characterized by graft-copolymerizing starch or micro-crystalline cellulose as backbone with acrylamide, while using potassium permanganate as initiator, hydrolyzing and thereafter reacting with alkyl-amino-carbinol. Optionally, the product may also contain additives. It has advantages in readily available raw materials, low cost of production, simple technology and mild reaction conditions. The product has good overall performance, high flocculating ability, wide applicability and is an ideal sludge-dewatering agent and sewage treating agent.

Abstract: Water-based, water-fast ink compositions are provided. The compositions contain an aqueous liquid vehicle, a colorant, e.g., a pigment, dye or stain, and a binder material capable of ionically or physically entrapping the selected colorant. The binder material contains two ionically associated components which form a matrix, and comprises either a combination of a monomeric polyacid and a monomeric polybase, or a combination of a basic polymer and an organic acid.

Abstract: An emulsion of a copolymer of carbon monoxide with an olefinically unsaturated compound dispersed in an aqueous diluent; a curable resin composition in the form of an oil-in-water emulsion comprising a copolymer of carbon monoxide with an olefinically unsaturated compound and a curing agent; and a polymer which is produced by grafting a polymer comprising poly(ethene oxide) moiety in its molecular structure onto a copolymer of carbon monoxide with an olefinically compound.

Abstract: An emulsion of a copolymer of carbon monoxide with an olefinically unsaturated compound dispersed in an aqueous diluent; a curable resin composition in the form of an oil-in-water emulsion comprising a copolymer of carbon monoxide with an olefinically unsaturated compound and a curing agent; and a process for producing a laminated wood composite comprising applying said curable resin composition onto wood parts of the composite, bringing the wood parts of the composite together such that curable resin composition is positioned between adjacent wood parts, and curing the curable resin such that after curing cured resin adheres adjacent wood parts to one another.

Abstract: A process for the preparation of a linear alternating copolymer of carbon monoxide with ethene and another olefinically unsaturated compound (A) wherein a copolymer of which the molar ratio (r.sub.1) of the monomer units originating in the olefinically unsaturated compound A to the monomer units originating in ethene is in the range of from 1:100 to 1:3, is prepared by contacting the monomers in the presence of a liquid diluent with a catalyst composition which is based on(a) a source of a Group VIII metal, and(b) a bidentate ligand of the general formula R.sup.1 R.sup.2 M.sup.1 --R--M.sup.2 R.sup.3 R.sup.4 (I) wherein M.sup.1 and M.sup.2 independently represent a phosphorus, arsenic or antimony atom, R.sup.1, R.sup.2, R.sup.3 and R.sup.4 independently represent unsubstituted or substituted hydrocarbyl groups and R represents a bivalent bridging group which consists of three atoms in the bridge of which the middle atom is a carbon or silicon atom which carries two monovalent substituents R.sup.5 and R.sup.

Abstract: A process for the copolymerization of carbon monoxide with an olefinically unsaturated in which the monomers are contacted with a catalyst composition which is based on a source of a Group VIII metal and a boron hydrocarbyl compound. Additional boron hydrocarbyl compound is added to the polymerization mixture during the copolymerization or when the catalyst has lost its activity. A process for recycling a polymerization catalyst is also presented. It includes the steps of recovering a Group VIII metal composition from a preceding copolymerization process for the preparation of a copolymer of carbon monoxide and an olefinicaIly unsaturated compound and adding a boron hydrocarbyl compound to the Group VIII metal composition.

Abstract: A two-component coating composition is disclosed wherein the binder components comprise: (a) an amino component comprising an aqueous solution and/or dispersion of at least one polyacrylate containing amino groups in a quantity sufficient to make said polyacrylate soluble and/or dispersible in water upon neutralization with acid; and (b) a polyisocyanate component containing free isocyanate groups. Also disclosed is the method of emulsifying component (b) into component (a).

Abstract: A process for producing a water-absorbing resin, which comprises polymerizing (D) an aqueous solution comprising (A) at least one monomer component selected from the group consisting of an unsaturated carboxylic acid and salts thereof; (B) a compound having two or more unsaturated groups in a molecule; and (C) a compound having two or more functional groups which are capable of reacting with carboxyl groups in a molecule, the polymerization being conducted in such a manner that the following conditions (a) to (c) are simultaneously satisfied: (a) the molar ratio (B)/(C) being in the range of from 2.times.10.sup.-3 to 300, (b) the polymerization being initiated by a redox polymerization initiator, and (c) the maximum reaction temperature being in the range of from 60.degree. to 100.degree. C, and a water-absorbing resin having a degree of reduction in absorption magnification of from 1 to 16, and n absorption magnification under pressure of from 20 to 40.

Abstract: The invention relates to contact lenses made from a copolymer comprising units of formula I ##STR1## wherein R.sup.1 and R.sup.2 are each independently of the other hydrogen, alkyl, alkoxyalkyl, organosilylalkyl or organosilyl, R.sup.3 and R.sup.4 are each hydrogen or, taken together, are a divalent alkylene radical containing up to 8 carbon atoms, and A is a divalent substituted 1,2-ethylene radical which is derived from a copolymerisable vinyl monomer by virtue of the vinyl double bond being replaced with a single bond. The invention further relates to the copolymers themselves, to the use thereof for making contact lenses, and to a process for making contact lenses from such copolymers.

Abstract: Water-based varnish for glass prepared by mixing, just before use, the following basic components:component A: aqueous dispersion of an acrylic polymer containing hydroxy functional groups,component B: trialkoxysilane containing an epoxy functional group,component C: zirconium and ammonium double carbonate containing ZrO.sub.2 (+HfO.sub.2) (19% to 20% by wt.), in the form of an aqueous solution, components B and C in the mixture amounting to 3 and 2 parts by wt., respectively, per 100 parts by wt. of A.

Abstract: Polyurethane polyurea particles are obtained by an interfacial polymerization reaction between a hydrophobic phase which is capable of forming a three-dimensional crosslinked structure by reaction and is a mixture comprising a polyisocyanate compound and a polyhydroxy compound with the isocyanate groups being stoichiometrically excessive, and a polyamine in an amount not more than one equivalent of the stoichiometrically excessive isocyanate groups in the hydrophobic phase, and by polyurethanization reaction inside the particles.

Abstract: Functionalized polymeric compositions are prepared by polymerizing ethylenically unsaturated functional monomer in a solvent including a reactive compound. The functional groups of the reactive compound and the functional monomer react during or subsequent to the polymerization of the functional monomer to provide functionalized polymeric composition. The reactive compound can be a hydroxy-terminated, poly(ethleneoxy)ated hydrophobe-bearing compound and the functional monomer can be a polymerizable carboxylated monomer, the functionalization in this case being a condensation. Removal of the water of condensation by azeotropic distillation drives the reaction to completion. The resulting high solids functionalized polymeric composition is soluble or dispersible in an appropriate solvent, and can be used as is, diluted with a solvent, or isolated.

Abstract: The emulsion polymerization of free-radical-polymerizable monomers in the presence of a branched, poly(ethylene oxide) having a molecular weight of 4,000 to 19,000 and 1 to 250 mmol of the sum of the alkali metal and ammonium ions which are not bound to the emulsifier per liter of aqueous phase provides coarse, aqueous plastic dispersions. The process allows for the effective control of the particle size in the dispersion and yields carboxylated rubber dispersions which are suitable for the production of coating materials for carpets and paper.

Abstract: A stable polyol-alkali metal silicate emulsion is produced by mixing and emulsifying an aqueous alkali metal solution, a polyol and an organic compound that will cause the aqueous alkali metal silicate solution to solidify. The polyol-alkali metal silicate emulsion may be used to react with compounds containing at least two isocyanate radicals to produce polyurethane silicate solid or foamed products which may be used for thermal and sound insulation, coating agents, adhesives, caulking agents and molded objects.

Abstract: Heterocyclic styryl compounds are prepared by condensing nitrogen heterocyclic compounds such as trimethyl pyridine with dialdehydes and heterocyclic aldehydes such as furfural. These can be further reacted and chain extended with bismaleimides or polymaleimides. The compounds and their reaction products are useful to make heat resistant composites with various fibers such as graphite fibers.

Abstract: There is provided hereby a coloring composition having an excellent water resistance and solution stability, which comprises a reaction mixture of(a) a vinyl compound soluble in water or in a water soluble organic solvent, with(b) a compound which contains more than two groups having a active hydrogen, at least one group of which is an amino group or imino group,in the presence of a water soluble dye and optionally a solvent.

Abstract: Polyesters containing significant amounts of dicyclopentadiene are produced and used in emulsion form. Superior physical properties, including low linear shrinkage, are obtained.

Abstract: Polyesters containing significant amounts of dicyclopentadiene are produced and used in emulsion form. Superior physical properties, including low linear shrinkage, are obtained.

Abstract: A water-soluble pressure-sensitive adhesive composition is described containing a polymerization product obtained by the solution polymerization of a water-soluble ethylenically unsaturated monomer in the presence of an alcoholic plasticizer having a molecular weight of less than about 3,000 and which is a liquid at room temperature, selected from the group consisting of polyether polyols and polyhydric alcohols, wherein the polymerization product contains as a polymer component at least an addition copolymer of the water-soluble ethylenically unsaturated monomer and the alcoholic plasticizer.

Abstract: A process for producing a water-absorbing resin, which comprises polymerizing (D) an aqueous solution comprising (A) at least one monomer component selected from the group consisting of an unsaturated carboxylic acid and salts thereof; (B) a compound having two or more unsaturated groups in a molecule; and (C) a compound having two or more functional groups which are capable of reacting with carboxyl groups in a molecule, the polymerization being conducted in such a manner that the following conditions (a) to (c) are simultaneously satisfied: (a) the molar ratio (B)/(C) being in the range of from 2×10−3 to 300, (b) the polymerization being initiated by a redox polymerization initiator, and (c) the maximum reaction temperature being in the range of from 60° to 100° C., and a water-absorbing resin having a degree of reduction in absorption magnification of from 1 to 16, and n absorption magnification under pressure of from 20 to 40.