Abstract: The invention relates to an initiator system comprising a diarylalkylamine compound and a sensitizing agent. The invention also relates to a hardenable composition comprising the initiator system. The invention further relates to the use of the initiator system for initiating the hardening process of a hardenable composition being selected from cationically curing composition(s) and/or radically curing composition(s) or a mixture thereof. The initiator system and the hardening composition can be used in various fields, including the dental and orthodontic area.

Abstract: The present invention relates to low temperature, cationically curable compositions with improved cure speed and toughness.

Abstract: This invention is in the field of polymer chemistry. More in particular it provides a method to produce polymers such as block copolymers or cross-linked networks that are suitable for medical applications. The invention also provides degradable materials that may degrade completely when used in the human or animal body, minimizing residual components that may be toxic or otherwise undesirable.

Abstract: A reaction-curable adhesive composition exhibiting acidity is formed form a weakly acidic to alkaline composition (I) comprising (a) a polymerizable monomer and (b) a compound represented by the following formula (I) and a strongly acidic composition (II) comprising (a) a polymerizable monomer. R1—C6H4—NR2CH2COOR3??(1) wherein R1 and R2 are each independently a hydrogen atom or an alkyl group which may have a functional group, and R3 is a hydrogen atom or a metal atom. The composition containing the polymerizable monomer can be stably stored for a long period of time.

Abstract: A dental adhesive composition comprising (i) at least one non-acidic polymerizable monomer having at least one ethylenically unsaturated group, (ii) optionally one or more acidic compounds, (iii) at least one photoinitiator, (iv) at least one solvent, and (v) about 0-40% by weight of one or more fillers; wherein the weight ratio of non-acidic polymerizable monomers/acidic compounds in the adhesive composition is more than about 4.5; the viscosity of the adhesive composition is less than about 350 centipoise (cP) at 25° C.; and the adhesive composition excluding solvent and filler has an acid number of less than about 0.75 mmol NaOH/g. The dental adhesive composition is used with a dental primer composition, which may be provided together in a kit.

Abstract: This invention relates to a process for producing high molecular weight (HMW) and ultra-high molecular weight (UHMW) acrylic polymers having unique polymer tacticity and exhibiting enhanced thermal and mechanical properties. This process comprises polymerizing ethylenically unsaturated monomer in the presence of a free radical initiator that results in a “living-like polymer” utilizing a multi-step approach. In conducting the process of this invention the “living-like polymer” is further dissolved in a liquid carrier, wherein the said liquid carrier is a reactive diluent that can be reacted subsequently by an addition polymerization process to create a block- or multi-block, copolymer or homopolymer. This process can be progressively repeated with the same or various different reactive diluents to generate desired architecture and molecular weight polymer(s) which can be used in further processing procedures to be manufactured directly into finished articles.

Abstract: Provided is a resin composition for stereolithography that absorbs little water and moisture over time in uncured state, maintains a low moisture absorption rate even under high humidity, and has high curing sensitivity, from which a stereolithography product excellent in the properties, such as dimensional accuracy, mechanical properties, and dimensional stability can be smoothly produced for reduced light irradiation time. The resin composition for stereolithography comprising an oxetane compound expressed by the general formula (I) below: wherein R1 denotes an alkyl group having 1 to 5 carbon atoms, and R2 denotes an alkylene group having 2 to 10 carbon atoms that may contain an ether bond, in the proportion of from 3 to 60 mass % based on the total mass of the resin composition for stereolithography.

Abstract: There are provided a compound represented by the following formula (I), a photopolymerizable composition containing (A) a photopolymerization initiator represented by the formula (I) and (B) a radical polymerizable monomer, a color filter produced by using the photopolymerizable composition, and a process for producing the color filter.

Abstract: It's object is to provide a (meth)acrylate compound excellent in photocurability, a curable composition comprising the compound and excellent in all of pattern accuracy, peelability, surface hardness, elasticity recovery and solvent resistance, an optical nanoimprint composition and a cured product of the curable composition and a method for producing it, especially to provide a composition favorable for a permanent film for flat panel displays, etc. A (meth)acrylate compound represented by the following formula (1): wherein R1 represents a hydrogen atom or a methyl group, R2 represents a substituent having carbon atoms of 2 to 6 and having a carbon-carbon double bond, X represents an organic group having carbon atoms of 1 to 10, m and n each are an integer of 1 to 3.

Abstract: The invention relates to silica-containing radiation-curable formulations which in the cured state offer a particular degree of corrosion control for metallic substrates.

Abstract: A bis(aminophenol) derivative having substituents at positions adjacent to two amino groups is provided. The bis(aminophenol) derivative is used as a raw material of a polyamide resin for a positive-tone photosensitive resin composition. A polyamide resin comprising bis(aminophenol) and a structure derived from a carboxylic acid is also provided, the bis(aminophenol) having substituents at positions adjacent to the two amino groups. A positive-tone photosensitive resin composition comprising a polybenzooxazole precursor resin, exhibiting high sensitivity and a high cyclization rate even when cured at a low temperature is provided. Also provided is a positive-tone photosensitive resin composition comprising a polyamide resin having an imide structure, an imide precursor structure, or an amide acid ester structure. The composition exhibits high sensitivity and produces a cured product having low water absorption even when cured at a low temperature.

Abstract: Solid-state deformation processing of crosslinked high molecular weight polymers such as UHMWPE, for example by extrusion below the melt transition, produces materials with a desirable combination of physical and chemical properties. Crosslinked bulk materials are heated to a compression deformable temperature, and pressure is applied to change a transverse dimension of the material. After cooling and stress relieving, a treated bulk material is obtained that has enhanced tensile strength in the axial direction orthogonal to the dimension change. In preferred embodiments, medical implant bearing materials are machined from the treated bulk material with the in vivo load bearing axis substantially parallel or coincident with the axial direction of the treated bulk material.

Abstract: A medical prosthesis for use within the body which is formed of radiation treated ultra high molecular weight polyethylene having substantially no detectable free radicals, is described. Preferred prostheses exhibit reduced production of particles from the prosthesis during wear of the prosthesis, and are substantially oxidation resistant. Methods of manufacture of such devices and material used therein are also provided.

Abstract: The invention concerns dental compositions. Said composition comprises (1) a silicone crosslinkable and/or polymerizable by cationic process; (2) an efficient amount of at least an initiator such as an organometallic complex borate; and (3) a dental filler present in the composition in a proportion of at least 10 wt. % relative to the composition total weight. Said dental compositions are useful for making dental prostheses or for dental restoration.

Abstract: Novel crosslink agents are described that provide for the copolymerization of at least one hydrophilic monomer with at least one lens monomer typically used to prepare materials for ophthalmic lenses. The new crosslink agents have a relatively high selectivity for the hydrophilic monomer and limited reactivity with the crosslink agent used to polymerize the lens monomer.

Abstract: The invention relates to a molding composition which is embodied as a molding composition, a thus produced molded body as a molded body, and a method for producing said molded body comprising a surface structure.

Abstract: The present invention is directed to an adhesive composition comprising a crosslinkable acrylic copolymer, a multi-functionalized crosslinkable oligomer and a photoinitiator wherein the composition exhibits excellent wet out characteristics as reflected in a tan delta value of at least 0.5, preferably greater than 0.5, more preferable greater than 0.8 as measured at 20° C. resulting from a first curing stage, and improved stiffness and temperature resistance as reflected in a storage elastic modulus of at least 300,000 Pa at 20° C. and a shear adhesion failure temperature of at least 425° F. (218.3° C.) at 1 Kg/in2 (0.155 Kg/cm2), respectively, which result from a second sequential curing stage.

Abstract: In a method for producing a lactic acid oligomer by subjecting an aqueous lactic acid solution to a polycondensation reaction under microwave irradiation, the polycondensation reaction is carried out under reduced pressure in the absence of a polymerization catalyst and an organic solvent. An initial polycondensation reaction is carried out under normal pressure, and thereafter, a reaction is carried out under reduced pressure. The pressure is reduced stepwise to give a final pressure of 2000 Pa or less. A lactic acid oligomer which has a high purity and is safe from hygiene point of view can be obtained at a low cost in a short time.

Abstract: A curable solid ink composition including a curable component, a non-curable component including an ethoxylated octylphenol derivative, a photoinitiator, and a colorant. The curable solid ink composition has a viscosity in the range of less than 10 cPs at 90° C., a shrinkage value of less than 3%, and a superior curing rate compared to existing curable solid ink compositions. The ethoxylated octylphenol derivatives may be prepared by reacting an ethoxylated octylphenol, a linear alcohol, and diisocyanates or polyisocyanates.

Abstract: This invention relates to polymerizable compositions comprising a salt of a barbituric acid derivative. The compositions are typically shelf-life stable and may be polymerized through mixing of an acidic component with the salt of a barbituric acid derivative.