Abstract: An artificial marble is herein disclosed which comprises a polymer (A) of a radical polymerizable vinyl compound, an inorganic filler (B) having an average particle diameter of 1 .mu.m or more, and a colloidal metal oxide (C) having an average particle diameter of 1 to 100 nm, the metal oxide (C) being uniformly dispersed in the state of substantially primary particles in the polymer (A). The colloidal metal oxide (C) can be uniformly dispersed, whereby a high flame retardancy can be imparted to the artificial marble, and the inorganic components can be filled in a higher ratio without impairing aesthetic properties peculiar to the artificial marble.

Abstract: A composite material having a structure in which negatively charged colloidal silica having an average particle diameter of not greater than 50 nm and remaining substantially in the form of primary particles is attached to the outer surfaces of negatively charged polymer particles. By using this composite material, there can be obtained molded articles wherein colloidal silica is dispersed in a resin while remaining substantially in the form of primary particles.

Abstract: An A-B-A type of block copolymer consisting of polymer block A of (meth)acrylate and polymer block B of olefin, having a Mw/Mn of 1.0 to 2.5, is disclosed. This block copolymer can be produced by polymerizing an olefin using a particular rare earth compound as an initiator, and then polymerizing the formed polymer with a (meth)acrylate.

Abstract: A coating composition comprising (a) a crosslinking polymerizable compound (a-1) having at least two (meth)acryloyloxy groups in the molecule, or a mixture of this compound (a-1) and a compound (a-2) copolymerizable therewith, (b) finely divided silica having its surfaces modified by a hydrolyzate of a mixture composed of a silane compound (b-1) capable of forming a bond with component (a), and a silane compound (b-2) incapable of forming a bond with component (a), and (c) a high-energy radiation polymerization initiator. This coating composition can form a cured film having high surface hardness and excellent weather resistance, and can be applied in solventless form.

Abstract: Disclosed is a process for producing dental polymeric shaped articles resistant to the adhesion of plaque which comprises the steps of shaping and curing a dental composition containing a monomer having at least one (meth)acryloyloxy group, and bringing the cured product into contact with a halogen or a halogen compound. Also disclosed is a dental composition comprising a monomer having at least one (meth)acryloyloxy group and a polymerization initiator, which is characterized by having added thereto at least one of a halogen and a halogen compound. When cured, this dental composition produces dental polymeric shaped articles resistant to the adhesion of plaque.

Abstract: Disclosed is a dental composition comprising a (meth)acrylic ester compound as the principal component and containing a polymerization initiator, which is characterized by having incorporated therein a grafted rubber obtained by polymerizing at least one ethylenically unsaturated monomer in the presence of a rubber. This dental composition can be cured to yield a cured product having excellent strength properties and, therefore, is particularly useful in applications such as a molar restoration material and a denture base resin.

Abstract: A material for dentistry having a low odor, a low stimulation and a proper dough stage time is here disclosed which is prepared by blending a monomer selected from the group consisting of (meth)acrylate compounds represented by the general formula ##STR1## R.sub.1 is a hydrogen atom or a methyl group, each of R.sub.3, R.sub.6 and R.sub.10 is an alkyl group, and each of R.sub.2, R.sub.5, R.sub.8 and R.sub.9 is an alkylene group) and (meth)acrylate dimers.

Abstract: This invention provides dental adhesive compositions consisting essentially of(a) an aliphatic amine salt of a polymerizable phosphoric ester, as represented by the formula ##STR1## where R and R' are specific radicals; (b) at least one radical-polymerizable unsaturated monomer; and(c) a radical polymerization initiator. These compositions are useful in bonding living dental tissue restoration materials to living tooth tissues, particularly to dentin.

Abstract: A visible light ray-curable monomeric composition for fastening loose teeth, comprising: a filler component consisting of fine, solid particles having an average size of 0.01 to 100 .mu.m and in an amount of 40% to 85% based on the weight of the total weight of the composition; a polyfunctional monomer component consisting of a radical-polymerizable, polyfunctional monomer; a monofunctional monomer consisting of a radical-polymerizable, monofunctional monomer; and a photopolymerization initiator; having a viscosity of 1,000 to 500,000 cps at a temperature of 25.degree. C., and contained in a light-shielded container.

Abstract: A dental adhesive composition containing as major components:(a) at least one isocyanate-group-containing urethane prepolymer,(b) at least one isocyanate-group-containing silane compound,(c) at least one radical-polymerizable unsaturated monomer, and(d) at least one initiator selected from the group consisting of redox polymerization initiators and photopolymerization initiatorsis disclosed.This composition is excellent in bonding properties when it is used to bond a living dental tissue with a restoring material such as a metal, organic polymer, and ceramic. Also, this adhesive composition does not require a troublesome pretreatment of the restoring material with an etching agent such as phosphoric acid when the restorating material is required to bond to the living tissue.

Abstract: A photopolymerizable dental composition, which comprises:(A) an organic composite filler obtained by polymerizing at least one carboxylic acid monomer of the formula: ##STR1## wherein R.sub.1 is a hydrogen atom, a C.sub.1 -C.sub.15 alkyl group, a --COOY group, a halogen atom, or a phenyl group or a derivative thereof; R.sub.2 is a hydrogen atom, a C.sub.1 -C.sub.15 alkyl group, a --COOZ group, a halogen atom, or a phenyl group or a derivative thereof; R.sub.3 is a hydrogen atom, a C.sub.1 -C.sub.15 alkyl group, a halogen atom, or a phenyl group or a derivative thereof; and each of X, Y and Z is a hydrogen atom, NH.sub.4 or an alkali metal atom; or the formula: ##STR2## wherein each of R.sub.4 and R.sub.5 is a hydrogen atom, a C.sub.1 -C.sub.

Abstract: Disclosed are dental adhesive compositions consisting essentially of(a) at least one urethane prepolymer containing one or more isocyanate groups, or a blend of the urethane prepolymer and an inert diluent;(b) at least one radical-polymerizable unsaturated monomer;(c) a photopolymerization initiator;and, if desired,(d) a polymerizable phosphoric ester compound having a specific structure.These dental adhesive compositions can be used to bond a restorative material to dentin without requiring any troublesome pretreatment with an etching agent such as phosphoric acid, and can exhibit bonding power sufficient for practical purposes.

Abstract: A photopolymerizable dental composition, which comprises:(A) an organic composite filler obtained by polymerizing a sulfonic acid or sulfonate monomer of the formula: ##STR1## wherein R.sub.1 is a hydrogen atom, a C.sub.1 -C.sub.20 alkyl group, a phenyl group or a derivative thereof, or a halogen atom; ##STR2## wherein each of R.sub.2 and R.sub.3 is a hydrogen atom or a C.sub.1 -C.sub.15 alkyl group, R.sub.4 is a C.sub.1 -C.sub.15 alkylene group, m is an integer of from 1 to 20 and n is an integer of from 0 to 20; and Y is a hydrogen atom, NH.sub.4 or an alkali metal atom, and at least one radical polymerizable vinyl monomer in a polymerization system in which an inorganic compound is dispersed;(B) a monomer mixture comprising 2,2-bis[4-(methacryloxyethoxy)phenyl]propane, at least one hexa-functional urethane (meth)acrylate of the formula: ##STR3## wherein X is ##STR4## wherein n is an integer of from 1 to 10, and each of R.sub.1 and R.sub.

Abstract: A method for preparing a polymeric composition in which an inorganic compound is firmly consolidated in an organic polymer, which comprises polymerizing at least one radical polymerizable vinyl monomer in an aqueous medium polymerization system comprising an inorganic compound dispersed in the presence of an organic acid monomer or organic acid salt monomer, by using a radical polymerization initiator.

Abstract: A photopolymerizable composition comprising a vinyl monomer, a mercaptocarboxylic acid/.alpha.-diketone photopolymerization initiator and a storage stabilizer. The composition may admit of a filler, and exhibits excellent mechanical strength, storage stability, color and resistance to coloring, and availability.

Abstract: A method for preparing a polymeric composition in which an inorganic compound is firmly consolidated in an organic polymer, which comprises polymerizing at least one radical polymerizable vinyl monomer in an aqueous medium polymerization system comprising an inorganic compound dispersed in the presence of an organic acid monomer or organic acid salt monomer, by using a radical polymerization initiator.

Abstract: Disclosed is a photopolymerizable dental composition consisting essentially of (A) a composite filler obtained by non-catalytically polymerizing a carboxylic acid monomer with a vinyl monomer in a polymerization system having an inorganic compound dispersed therein; (B) a monomer mixture composed of 2,2-bis[4-(methacryloxyethoxy)phenyl]propane, at least one hexafunctional urethane methacrylate having an isocyanuric acid skeleton, and an ethylenic vinyl monomer diluent; and (C) a photopolymerization initiator. The composite resin obtained by curing this dental composition has high mechanical strength and good water resistance.