Abstract: A photopolymerizable adhesive consisting of Compound (1) which contains at least one (meth)acryloxy group as a polymerizing group in its molecule, and other structures constructed from the group(s) selected from the group consisting of alkyl group, alkyloxy group, polyalkoxy group, siloxanyl group and the substituted group thereof substituted by fluorine, hydroxy or alkoxy group; Compound (2) selected from (meth)acrylic acids, hydroxyalkyl (meth)acrylates, (meth)acryloxyalkyl succinic acids, trialkoxyvinyl silanes and .gamma.-(meth)acryloxyalkyl trialkoxy silanes; and Compound (3) selected from hydroxyacetophenones, acetophenones, glyoxy esters and camphorquinones, wherein said adhesive comprises 3 to 60 wt % of the compound (2), and 0.1 to 2 wt % of the Compound (3).

Abstract: Photopolymerization initiator for the visible light-polymerizing adhesives; and the visible light-polymerizing adhesives comprising the photopolymerization initiator, an aliphatic tertiary amine and a radical polymerizing monomer. The visible light-polymerizing adhesive of the invention has good transparency without coloring after photopolymerization as well as good adhering activity. It also has colorless, good transparency after photopolymerization and good adhering activity in an UV irradiation test, as well as excellent light resistance showing very little color change and deterioration in an UV irradiation test. The visible light-polymerizing adhesive of the invention is also excellent in photopolymerizing activity. Furthermore, the visible light-polymerizing adhesive of the invention has photopolymerizing activity not only to visible light but also to near-UV. It hardly has problems of such decrease in transparency caused by both kinds of lights as coloring and color change.

Abstract: This invention relates to a photocuring adhesive characterized in that a photoinitiator is added to a monomer composition comprising 20 to 50 wt % of the oligosiloxanyl di(meth)acrylate represented by the structural formula (1) shown below, 20 to 60 wt % of a hydrophobic mono (meth)acrylate having a hydrocarbon group containing no less than six carbon atoms in a side chain, and 1 to 80% of a hydrophilic monomer capable of undergoing free radical polymerization: ##STR1## R.sub.1 and R.sub.2 both being either hydrogen or methyl, m.sub.1 and m.sub.2 being an integer in the range 2 to 5, and n being an integer in the range 5 to 30.

Abstract: A photosetting resin comprising a liquid monomer composition and a photopolymerization initiator, the monomer composition containing a compound represented by the following formula (1) and a compound represented by the following formula (2) in a weight ratio within the range from 97:3 to 50:50: ##STR1## (wherein R.sub.1 is H or CH.sub.3, and 0.ltoreq.m.sub.1 +m.sub.2 .ltoreq.4) ##STR2## (wherein R.sub.2 is H or CH.sub.3, and 5.ltoreq.n.sub.1 +n.sub.2 .ltoreq.12).This photosetting resin can provide a cured resin which is excellent in both strength and toughness.

Abstract: Disclosed herein are an orthodontic bracket which comprises a photopolymerization-type adhesive layered and fixed on a back surface portion of a bracket main body made of a light-transmitting material, a kit which comprises the bracket hermetically sealed in a light-shielding container, and a process for the adhesion of the bracket.

Abstract: A bracket for orthodontics having a bracket body made of a composite resin material and a thin layer of a synthetic resin material in a dental adhesive. The synthetic resin layer is laminated on the base surface of the bracket body in such a manner that the composite resin material of the bracket body and the synthetic resin of the thin layer are mingled with each other at the boundary therebetween. The thin resin layer is composed of polymethyl methacrylate having an average molecular weight of 1000,000 or less or a polymethacrylate copolymer.

Abstract: A method and apparatus to continuously harden articles made of visible light-curable resins, including continuously moving the articles to be hardened relative to a multiplicity of sources of visible light which are independently controllable to be able to vary the radiation to which the articles is exposed during its passage while independently controlling the temperature at which this takes place; and apparatus to accomplish this such that a large number of the objects to be irradiated passing through the hardening apparatus have the same exposure history to the visible light and to heating or cooling respectively. As the result, there is substantially no variation in the physical properties of these photo-polymerized products.

Abstract: A method to continuousky harden light-curable resins, by irradiating at least one shaped article made of a light-curable resin by continuously moving the article past a multiplicity of light sources while changing the flux of the irradiated light in multiple steps corresponding to the moving positions of the object and an apparatus to accomplish this method including means to continuously move the article relative to the multiple irradiation sources and means to adjust the flux density in multiple steps corresponding to the moving positions of the article. Specifically, the flux density of the light irradiated on the moving article is changed stepwide depending upon the position and the location of the article and the polymerization speed of the article and the hardening depth can be controlled in relation to its position and time.

Abstract: Dental light-curing resins are cured with light and under pressure by placing the uncured resin on a cast or mold or dental appliance to be prepared then covered with a transparent or translucent flexible membrane or sheet. In a chamber gas pressure is applied to the sheet and, in turn, to all parts of the underlying resin and, while pressurized, the resin is exposed to light to cure it.

Abstract: A soft contact lens having a high water content, high mechanical strength and good dimensional stability is disclosed, which is made of a copolymer comprised of at least one monomer represented by formula (1): ##STR1## wherein R.sup.1 and R.sup.2 each represents hydrogen atom, methyl group, or ethyl group, and n.sub.1 represents 0 or an integer of 1 to 3.

Abstract: A high-hydration contact lens having a high strength is disclosed which is made of a copolymer composed of (i) 40 to 90 wt. % of N,N-dimethyl acrylamide, (ii) 5 to 50 wt. % of a hydrophobic monomer, (iii) 0.1 to 10 wt. % of an unsaturated carboxylic acid having one ethylenically unsaturated bond, and (iv) 0.01 to 5.0 wt. % of a crosslinking agent, wherein the hydrophobic monomer is selected from the group consisting of phenyl acrylates, benzyl acrylates, phenyl methacrylates, benzyl methacrylates, alkyl acrylates, alkyl methacrylates, cyclohexyl acrylates and cyclohexyl methacrylates, and the crosslinking agent is selected from those represented by formula (I), (II), or (III) ##STR1## wherein X represents a hydrogen atom or a methyl group, a is an integer of 2 to 23, and b and c each is an integer of 2 to 14.

Abstract: A lens having a high refractive index with a low dispersion produced by copolymerizing a polyfunctional allyl monomer with at least one monomer selected from the group represented by the general formula A: ##STR1## X: H, CH.sub.3, Cl Y: H, CH.sub.3, C.sub.2 H.sub.5, n-C.sub.3 H.sub.7, iso-C.sub.3 H.sub.7, OCH.sub.3, C.sub.6 H.sub.11, Cl, Br, CH.sub.2 Cl, CH.sub.2 Br, C.sub.6 H.sub.5, CH.sub.2 C.sub.6 H.sub.5, SCH.sub.3m=0, 1, 2n=0, 1, 2, 3, 4, 5.This lens is excellent in its transmittance, pencil hardness, impact resistance, dyeability, coating adhesion, solvent resistance, workability, etc.

Abstract: A high refractive lens of a terpolymer produced by the polymerization of ternary monomers comprising diethylene glycol bisallyl carbonate, triallylisocyanurate, and benzyl methacrylate. This lens is considerably improved in its physical properties necessary for lens such as superficial hardness, transmittance, and adhesion strength of glass film coated on the surface, as well as having a high refractive index.

Abstract: The present invention relates to a copolymer for high refractive lens having a refractive index equal to or higher than 1.55, obtained by copolymerization of one or more of the first monomer component having the formula (I) ##STR1## wherein R.sub.1 signifies hydrogen atom or methyl radical, R.sub.2 signifies hydrogen atom or methyl radical, and m and n signify integers 0 to 4 in total, with one or more of the radically polymerizable second monomer component, homo-polymer of which has a refractive index equal to or higher than 1.55 and, if necessary, with the radically polymerizable third monomer component, the homo-polymer of which has a refractive index lower than 1.55 and to the lens prepared from said copolymer.

Abstract: In producing an aqueous emulsion containing substantially no emulsifier, an aqueous polymer emulsion remarkably elevated in chemical stability is obtained by copolymerizing a specific amount of a particular vinyl monomer containing polyoxyethylene units as an indispensable copolymerization component.