Desoto, Inc.

Stamicarbon B.v.

Other

Alliedsignal Inc.

International Minerals & Chemical Corp.

John J Krajewski

Edward Joseph Murphy

Gerry K Noren

John Monroe Zimmerman

Robert E Ansel

John T Vandeberg

Sami A Shama

Danny C Thompson

Timothy Edward Bishop

Clive J Coady

George David Green

James R Snyder

Joseph E Gaske

Christopher E Fisher

William J Lang

A radiation curable coating composition comprising acrylate oligomers and monomers, vinyl ether monomers, and a free radical photoinitiator. The vinyl ether monomers replace N-vinyl-pyrrolidone or other undesirable reactive diluents while retaining or modifying the properties of coatings using such diluents.

Free radical co-polymerization of acrylates and vinyl ethers

A free-radical radiation curable composition comprising:

Free-radical curable compositions comprising vinyl ether and urethane

Free-radical curable compositions

The present invention contemplates a stereolithographic apparatus and method having a liquid organic phase and a fluid phase separated by a membrane that inhibits contact between the phases.

Stereolithographic method and apparatus in which a membrane separates

A method of coating a concrete floor is disclosed in which the concrete surface is coated with a homogeneous liquid coating composition containing maleate or fumarate unsaturation in combination with vinyl ether unsaturation and a ketonic photoinitiator, the wet coating is allowed to seep into the concrete surface and to flow out on the concrete surface to form a smooth coating, and this coating is cured by exposing it at light having a wavelength in the range of from about 200 to about 600 nanometers.

Method of coating concrete floors with photocurable coatings

A cationically curable polyurethane composition comprises the reaction product of an organic polyisocyanate with a transvinylation polyhydric alcohol mixture containing hydroxy groups. The polyisocyanate consumes substantially all of the available hydroxy groups in the transvinylation polyhydric alcohol mixture. These compositions are particularly useful in stereolithography. A method of transvinylation utilizing ultrasonic energy is also disclosed.

Cationically curable polyurethane compositions having vinyl ether

A method of curing a three-dimensional specimen of preformed cross-linked polymeric material containing polymerizable ethylenically-unsaturated material is provided in which the specimen is immersed in water having dissolved therein an amount of a water-soluble organic free-radical polymerization catalyst effective to transfer a polymerization-initiating amount of the catalyst into the preformed cross-linked polymeric material. This specimen containing the water-soluble organic free-radical polymerization catalyst is heated to a temperature causing polymerization, and is maintained at that temperature while the cure is completed. The aqueous bath preferably contains a catalyst mixture which includes a catalyst of oxidizing character in admixture with a reducing agent, such as an amine, and is maintained at a polymerization temperature of from 60.degree. C. to 100.degree. C. so that immersion of the specimen in a single bath completes the cure.

Postcuring of unsaturated stereolithographic specimens using aqueous

An improved stereolithographic process is provided in which the formation of a thin walled three-dimensional object in a reservoir of liquid ultraviolet-curable ethylenically unsaturated material using a support is positioned immediately beneath the upper surface of the liquid reservoir with that upper surface being exposed to ultraviolet light in a pattern to solidify the liquid at and near the upper surface in a series of cross-sections of the desired three-dimensional object, one atop the other. In this way there is formed a series of superposed layers which adhere to one another to build the desired three-dimensional object within the liquid reservoir. The improvement comprises, stopping the exposure at any portion of the surface in the formation of said layers and then repeating the exposure at least once again in the production of each surface layer so that the strength and solvent resistance of the formed object are increased and its distortion is minimized. The ultraviolet exposure of each surface layer is preferably carried out as a series of rapid repeated scans of a computer-directed focused laser.

Stereolithography using repeated exposures to increase strength and

A stereolithographic method which employs an ultraviolet-curable liquid composition adapted to cure rapidly to a lightly cross-linked solvent-swellable three-dimensional complexly-shaped polymeric thin-walled element constituted by heat-softenable solid polymer upon exposure to ultraviolet dosage in the range of about 0.1 to about 10 Joules per square centimeter and which possesses reduced distortion comprises, from 20 to 80 weight percent, of a resinous polyacrylate or polymethacrylate dissolved in a combination of 10 to 45 weight percent of a liquid polyacrylate or polymethacrylate, which is preferably trifunctional, and 10 to 45 weight percent of liquid N-vinyl monomer, preferably N-vinyl pyrrolidone. Thus, the weight ratio of polyacrylate: polymethacrylate: N-vinyl monomer is about 1:2:2 to about 8:1:1. One of the foregoing polyacrylates or polymethacrylates is a polyacrylate and the other is a polymethacrylate so that good cure speed is accompanied by good distortion resistance. In the method, a reservoir of the liquid composition is established and its exposed surface is irradiated to solidify the surface and build up a thin-walled element which is removed from the reservoir, drained of liquid adhering thereto and cured.

Method of forming a three-dimensional object by stereolithography and

A method of investment casting utilizes a pattern produced by stereolithography in which a three-dimensional specimen is provided by light cure of ethylenically unsaturated liquid material. The stereolithography composition is constituted by the ethylenically unsaturated liquid material in admixture with an inert low thermoplastic material which weakens the pattern when heated within the mold used in the investment casting process to prevent the thermal expansion of the pattern from cracking the mold.

Investment casting utilizing patterns produced by stereolithography

An ultraviolet curing liquid coating composition which, when cured with ultraviolet light in the presence of an appropriate photoinitiator, provides a coating adapted for the coating of optical glass fiber. This coating composition comprises as the essential component, an acrylate-terminated polyurethane oligomer based on a polyfunctional core which is at least trifunctional and which supports one branch for each functionality in the core. Each of the branches leads to an acrylate-functional terminal group, with there being from about 150 to about 2500 units of molecular weight in each branch between the trifunctional core and the acrylate-functional terminal group. Depending primarily upon the molecular weight of the branches, one can provide coating compositions for buffer coat, single coat or topcoat use.

Ultraviolet curable coatings for optical glass fiber based on a

An ultraviolet curing liquid coating composition is disclosed which, when cured with ultraviolet light in the presence of an appropriate photoinitiator, provides buffer coatings for optical glass fiber having adequate strength at room or expected elevated temperature and stability at such elevated temperature, a high index of refraction above 1.48, and a low tensile modulus which remains low to resist microbending difficulties down to around -60.degree. C. This coating composition consists essentially of a linear polyacrylate-terminated polyurethane or polyurea oligomer having a room temperature tensile modulus of at least 100 psi., and a tensile modulus at -60.degree. C. which is less than 175,000 psi., when capped with 2-hydroxyethyl acrylate and cured with ultraviolet light, in admixture with a liquid acrylate-functional material which does not increase the low temperature hardness and which provides the liquidity needed for coating application. The oligomer is instead capped with a monohydric polyacrylate to provide improved cure speed without eliminating resistance to low temperature microbending.

Polyacrylated oligomers in ultraviolet curable optical fiber coatings

A radiation-curable diethylenically unsaturated polyurethane resin is disclosed which cures to provide cured coatings possessing reasonable physical integrity at room temperature, a tensile modulus of less than about 10000 psi at -40.degree. C., preferably less than 5000 psi at -60.degree. C., and a high index of refraction, above 1.48. This polyurethane resin is constituted by an essentially saturated, halogenated, dihydroxy-terminated linear liquid polybutadiene polymer, in which the halogen is preferably chlorine, reacted with an organic diisocyanate and a monoethylenically unsaturated monomer carrying a single hydroxy group to form a diethylenic diurethane having a halogen-containing essentially saturated polybutadiene backbone. Coating compositions are disclosed which consist essentially of the above diethylenically unsaturated diurethane having a polybutadiene backbone together with less than 40% of a liquid solvent therefor which is preferably a monoethylenically unsaturated liquid having a low glass transition temperature, and the compositions preferably include a photoinitiator enabling cure on ultraviolet exposure. These coatings are used as a buffer coating on optical glass fiber.

Optical fiber buffer coated with halogenated dihydroxy-terminated

There is disclosed linear polymers and copolymers of polymerized monoethylenically unsaturated monomers having a weight average molecular weight from about 1,500 to about 15,000, with most of the polymer ends being terminated with hydroxyl groups, one at each end of the polymer molecule. These polymers have an average of from about 1.6 to 5 hydroxyl groups per polymer molecule. Thermosetting coating compositions containing these polymers are also disclosed. The monomers which are polymerized may include a small proportion of hydroxy-functional monomers, but desirably consist of monoethylenically unsaturated monomers lacking hydroxyl functionality. The polymers are produced by polymerizing the monoethylenically unsaturated monomers in organic solvent solution medium containing a free radical initiator and a proportion of a chain-terminating agent which is a bis hydroxyorganic xanthogen disulfide in which the organic group is preferably an alkylene group contains from 2-18 carbon atoms to provide the desired molecular weight. The polymers are preferably liquid to slowly flowable at room temperature in the absence of organic solvent.

Growing community of inventors

Wheeling, IL, United States of America

John J Krajewski