American Can Company

James River-norwalk, Inc.

Sheldon I Schlesinger

Veronica Cochran

Ronald J Boszak

Dennis E Kester

Walter S Cerenzia

Thomas D Wilson

A method of forming pressed paperboard and pressed paperboard articles from a cellulosic fiber pulp, wherein the paperboard or paperboard articles has improved high temperature properties required of ovenable cookware. A preformed sheet or blank formed from a cellulosic fiber pulp, and having a water content in a range of from about 50% to about 100% by weight, is placed in an unheated press or mold to form the sheet or blank at a pressure in the range of from about 160 psi to about 2600 psi and then dried. When compared with hot press dried paperboard or shaped paperboard articles, such as ovenable baking trays, the products of the method of this invention have superior burst strengths after exposure to a temperature of 450.degree. F. (232.degree. C.) for one hour.

Manufacture of molded paperboard articles

Photopolymerizable compositions using sulfonium salt photoinitiators to effect polymerization of cationically polymerizable monomers additionally include a stable free radical to reduce or eliminate the sulfur odor generated upon photodecomposition of the sulfonium salt photoinitiator. The stable free radicals are soluble in the polymerizable material and are stable in the composition at ambient temperatures. Especially useful is 2,2-diphenyl-1-picrylhydrazyl.

Cationically polymerizable compositions containing sulfonium salt

An epoxide coating composition which is relatively stable to ambient white light and activated upon exposure to ultraviolet light to produce a hard glossy coating includes a cationically polymerizable material consisting at least principally of an epoxide prepolymer. Also included are a titanium dioxide pigment and a photoinitiator component including a first photoinitiator compound selected from the class consisting of hexafluorophosphate, fluoroborate, fluoroantimonate or fluoroarsenate salts of the following diazonium compounds: 2,5-diethoxy-4-p-tolylmercaptobenzene diazonium, 4-chloro-2,5-dimethoxybenzene diazonium, 2,5-dimethoxybenzene diazonium, 2,5-dimethoxy-4-p-tolylbenzene diazonium and 2,5-dibutoxy-4-benzamidobenzene diazonium, and mixtures thereof. The preferred compositions additionally contain a second photoinitiator compound which is relatively stable to radiation having a wavelength of at least 355 nanometers and decomposable by radiation in the range of 200-355 nanometers. Coatings of the foregoing compositions containing certain epoxidic esters and epoxidic ethers are curable at ambient temperature to a hard glossy surface within one minute.

Photopolymerizable epoxide coating compositions containing titanium

Photopolymerizable compositions using sulfonium salt photoinitiators to effect polymerization of cationically polymerizable monomers as essentially the sole polymerizable material additionally include an organic sulfur compound scavenger to reduce or eliminate the sulfur odor generated upon photodecomposition of the sulfonium salt photoinitiator. The scavengers are simultaneously activated by the electromagnetic radiation to react with the organic sulfur compound concurrently generated and are selected from the group consisting of aromatic ketones, benzoin compounds, aryloin oxime compounds, organic peroxide compounds, and benzil compounds.

Copolymers of glycidyl methacrylate and allyl glycidyl ether having pendant epoxy groups, having an inherent viscosity of at least about 0.25, preferably within the range of about 0.25 to about 0.38, and an epoxy equivalent of at least about 0.65 epoxide equivalent per 100 g. of polymer are provided which upon admixture with a radiation-sensitive aryldiazonium salt provide compositions which exhibit improved sensitivity, curing rates and other properties. Articles for recording and storing information from a laser source and other articles such as microfilm are derived from such compositions by subjecting a coated substrate to an energy source of sufficient intensity to decompose the radiation-sensitive catalyst and thus effect polymerization via the epoxy groups of the copolymer.

Radiation sensitive composition comprising copolymer of glycidyl

Photopolymerizable compositions and processes for photopolymerizing such compositions are provided, said process comprising admixing with said epoxides, photosensitive organohalogen compounds and thereafter applying energy to the resulting mixture. The organohalogens decompose to liberate an active catalyst which then serves to initiate polymerization of the epoxide material.

Compositions with organohalogen compound and diazonium salts as

Copolymers of glycidyl acrylate and allyl glycidyl ether and terpolymers derived from addition of glycidyl methacrylate to the polymerizable mixture, having an inherent viscosity within the range of about 0.09 to 0.28 and an epoxy equivalent of at least about 0.64 per 100 g. of polymer are provided which upon admixture with a catalyst which is a radiation-sensitive aryldiazonium salt of a complex halogenide, provides compositions suitable for use in a dry photopolymer positive imaging process. In the process, the polymer which is non-tacky at room temperature, together with the catalyst is applied to a substrate and exposed to an energy source for example, electromagnetic radiation through a transparency or mask. Following exposure, the coating is heated to the softening point of the unexposed portion of the coating and a powder or toner is applied thereto, the toner being adhered to only the tacky, non-exposed area of the coating, resulting in a pigmented image.

Powdered tonor image containing article

Dry photopolymer imaging process

Polymerization of polymerizable compositions comprising mixtures of lactones with monomeric or prepolymeric epoxides is effected by mixing such compositions with radiation-sensitive aromatic diazonium salts which decompose upon application of energy such as electromagnetic radiation to release Lewis Acid to initiate polymerization of said monomers.

Photopolymerization of lactone-epoxide mixtures with aromatic diazonium

Copolymers of glycidyl acrylate and allyl glycidyl ether and terpolymers derived from addition of glycidyl methacrylate to the polymerizable mixture, having an inherent viscosity within the range of about 0.09 to 0.28 and an epoxy equivalent of at least about 0.64 per 100 g. of polymer are provided which upon admixture with a catalyst which is a radiation-sensitive aryldiazonium salt of a complex halogenide, provides compositions suitable for use in a dry photopolymer positive imaging process. In the process, the polymer which is non-tacky at room temperature, together with the catalyst is applied to a substrate and exposed to an energy source for example, electromagnetic radiation through a transparency or mask. Following exposure, the coating is heated to the softening point of the unexposed portion of the coating and a powder or toner is applied thereto, the toner being adhered to only the tacky, nonexposed area of the coating, resulting in a pigmented image.

Dry photopolymer imaging article having a diazonium salt and epoxide

Copolymers of glycidyl methacrylate and allyl glycidyl ether having pendant epoxy groups, having an inherent viscosity of at least about 0.25, preferably within the range of about 0.25 to about 0.38, and an epoxy equivalent of at least about 0.65 epoxide equivalent per 100g. of polymer are provided which upon admixture with a radiation-sensitive aryldiazonium salt provide compositions which exhibit improved sensitivity, curing rates and other properties. Articles for recording and storing information from a laser source and other articles such as microfilm are derived from such compositions by subjecting a coated substrate to an energy source of sufficient intensity to decompose the radiation-sensitive catalyst and thus effect polymerization via the epoxy groups of the copolymer.

Growing community of inventors

East Windsor Township, NJ, United States of America

Sheldon I Schlesinger