Abstract: Photosensitizers containing saturated and unsaturated polycyclic compounds containing the cyclopentane-2-diazo-1,3-dione structural unit.These compounds have their maximum u.v. absorption at around 248 nm, decompose into polar products upon irradiation, and can be used as photosensitizers in positive deep u.v. or excimer laser (248 nm) lithography. They are most preferably useful with deep u.v. transparent resins for forming photoresists.
Type:
Grant
Filed:
June 29, 1989
Date of Patent:
August 13, 1991
Assignee:
Hoechst Celanese Corporation
Inventors:
Chengjiu Wu, Anne Mooring, James T. Yardley
Abstract: A process is provided for removing volatile materials from a molten oxymethylene polymer, according to which the molten polymer is passed through a rotating disk polymer processor having at least three stages; a first devolatilization stage, then a stabilization stage and then a second devolatilization stage. The molten polymer in the first devolatilization stage is maintained at a temperature above its melting point in the temperature range of from about 160.degree. C. to about 220.degree. C. and at a vapor space pressure of from about 0.1 to about 300 Torr. The polymer in the stabilization stage is maintained in the molten state at a temperature of from 160.degree. C. to about 220.degree. C. The polymer in the second devolatilization stage is maintained in the molten state at a temperature of from about 160.degree. C. to about 190.degree. C. and at a vapor space pressure of from about 0.1 to about 100 Torr.
Type:
Grant
Filed:
November 12, 1985
Date of Patent:
September 8, 1987
Assignee:
Celanese Corporation
Inventors:
Douglas W. Steele, George S. Nash, John W. Dorsey, Ronald S. Christy, Timothy L. Burns
Abstract: A polybutylene terephthalate is manufactured by the steps of polycondensating in the liquid phase terephthalic acid or a lower alcohol ester thereof as the acid component and 1,4-butanediol as the diol component to obtain a prepolymer of polybutylene terephthalate, solidifying the prepolymer and further polymerizing the prepolymer in the solid phase to obtain a polybutylene terephthalate of a higher polymerization degree, 0.001 to 5 percent by weight, based on the prepolymer, of a nucleator being added to the polymerization mixture at any time during a period of from the monomer-mixing stage before the starting of the solid phase polymerization, the solid phase polymerization being conducted in the presence of the nucleator uniformly dispersed in the polymerization mixture. The solid polymerization can be treated subsequently to the liquid polymerization and can proceed in a short time.
Abstract: There is provided an improved molding resin capable of being molded into an article exhibiting reduced tendency to corrode a copper surface when the molded resin and the copper surface are placed in spaced relationship in a common unventilated atmosphere at elevated temperatures, as measured by the Bell Telephone Laboratories Copper Corrosion Test at temperatures within the range of from 150.degree. to 175.degree. C., wherein the molding resin comprises the combination of (a) a butyleneterephthalate polyester comprising a brominated copolyester as a polymeric flame retardant comprising aromatic halogen groups in a flame retardant amount, and (b) an alkylhydroxyphenylalkanoyl-hydrazine in an amount that is within the range of from 0.05 to 0.3% by weight.
Type:
Grant
Filed:
May 7, 1984
Date of Patent:
August 20, 1985
Assignee:
Celanese Corporation
Inventors:
Wilfred L. Shearer, Stephen M. Sinker, Richard A. Wolf
Abstract: A thermoplastic resin composition comprises a crystalline thermoplastic resin, a reinforcing fiber, a flaky filler and polycarbonate and is suitable for molding.
Abstract: Disclosed is a novel filled continuous thermoplastic sheet material highly suitable for use in electrical applications, such as in the production of printed circuit boards. This material comprises an extruded sheet of a thermoplastic polymer, preferably poly(1,4-butylene terephthalate), containing from about 5 to 60% by weight of reinforcing filler material such as glass fibers, and having a polymer-rich surface, a gloss value of at least 15, and a maximum roughness of about 150 microinches.
Abstract: Microcapsules having a core of an alkaloidal material surrounded by a protective cross-linked polymeric wall are disclosed. The microcapsules are produced by intermixing a polymeric wall material with a liquid vehicle to form a solution thereof as a continuous first phase, and mixing the solution with an alkaloidal material. The produced admixture is agitated to disperse the alkaloidal material as a plurality of discrete minute core material entities in the first phase, and thereafter, phase separation is induced to separate the polymeric wall material from the liquid vehicle so that the wall material forms embryonic sheaths about the core material entities. The polymeric wall material is then cross-linked to form protective walls around each of the core material entities.
Abstract: A thermoplastic polyester composition comprising a thermoplastic polyester resin containing a moiety derived from an aromatic dibasic acid, as a predominant acid moiety and a hydantoin compound in an amount sufficient to substantially retard evolution of aromatic dibasic acid vapor during melt processing of the composition. A method of preventing mold deposits during a molding operation of a thermoplastic polyester resin containing an aromatic dibasic acid as a predominant acid moiety comprising the addition of 0.01 to 10 parts by weight of a hydantoin compound per 100 parts by weight of the polyester resin. The aromatic dibasic acid is preferably terephthalic acid and the thermoplastic polyester resin is preferably selected from the group of polyethylene terephthalate, polytrimethylene terephthalate, polytetramethylene terephthalate and blends thereof.
Abstract: A textile or textile-like polyester element having improved adhesion to rubber and being characterized by a high surface energy, a chemically unmodified surface and a coating which is a crystallizing agent for the polyester substrate.
Abstract: A novel polyester is provided which has been found to exhibit an anisotropic melt phase at a temperature which enables it readily to undergo melt processing to form quality fibers, molded articles, etc. The polyester of the present invention is different in character than polyesters of the prior art and includes as essential ingredients moieties derived from para-hydroxy benzoic acid, 1,2-bis(para-carboxy phenoxy)ethane, terephthalic acid, and substituted hydroquinone in the proportions indicated. The polyester of the present invention generally can be more economically produced than polyesters of the latter three moieties (two of which are relatively expensive) while surprisingly yielding an anisotropic melt of relatively low viscosity at a desirable temperature for melt processing in spite of the substantial concentration of relatively stiff para-oxybenzoyl moieties which contribute to the overall nature of the resulting polyester.
Abstract: A novel polyester is provided which has been found to exhibit an anisotropic melt phase at a temperature which enables it readily to undergo melt processing to form quality fibers, molded articles, etc. The polyester of the present invention is different in character than polyesters of the prior art and includes as essential ingredients moieties derived from para-hydroxy benzoic acid, 1,2-bis(para-carboxy phenoxy)ethane, terephthalic acid, and unsubstituted hydroquinone in the proportions indicated. The polyester of the present invention can be produced on a relatively economical basis and has been found capable of yielding an anisotropic melt of relatively low viscosity at a desirable temperature for melt processing. In a preferred embodiment the polyester is capable of undergoing melt processing at a temperature below approximately 300.degree. C., and in a particularly preferred embodiment at a temperature below approximately 290.degree. C. (e.g.
Abstract: Tobacco substitutes exhibiting improved particulate matter delivery and pressure drop characteristics are prepared by producing a film containing a blowing agent and heating the film to a temperature sufficient to cause gasification of the blowing agent.
Abstract: Filaments and fibers formed from a ternary fibre-forming polyamide consisting essentially of the polymeric condensation product of (1) at least 50 percent by weight of hexamethylene diammonium adipate, (2) 20-40 percent by weight of hexamethylene diammonium terephthalate and (3) 2-20 percent by weight of a third polyamide.
Abstract: A method of making a drawn filament from a hot drawable poly-phenylene-1,3,4-oxadiazole having p-phenylene radicals or p- and m-phenylene radicals, with substituted bromine, wherein a solution of the polymer is dry jet wet spun into a coagulant, and the undrawn filament stretched at least 6 times, at least two times at a temperature of at least 350.degree. C.
Abstract: An improved synthetic material adapted for use in smoking products is prepared by intimately mixing a suitable matrix material with a combustion modifier and a minor amount of an alkali metal or alkaline earth metal salt of an organic acid.
Abstract: A tobacco-substitute smoking material is provided which, in the preferred embodiment includes a polysaccharide, such as cellulose or a derivative thereof, as a combustible organic ingredient. A tobacco alkaloidal material, such as nicotine or a derivative thereof, is incorporated into the smoking material in the form of a plurality of combustible microcapsules containing the tobacco alkaloidal material.
Type:
Grant
Filed:
March 13, 1978
Date of Patent:
April 1, 1980
Assignee:
Celanese Corporation
Inventors:
Hubert Bradley, Jr., Robert G. Bayless, Ronald L. Hart, Danny A. Davis
Abstract: The present invention comprises a seat cushion for preventing excessive pressure on the coccyx of a person sitting on the cushion; the cushion is made from a seat pad having a casing with a resilient cushioning element positioned within; the cushioning element has a recessed portion in the rear center so as to be in underlying relationship to the coccyx; the casing is free of a recessed portion and provides nominal support for the coccyx.
Abstract: A textile or textile-like polyester element having improved adhesion to rubber and being characterized by a high surface energy, a chemically unmodified surface and a coating which is a crystallizing agent for the polyester substrate.
Abstract: A conventional gear pump is modified by the incorporation of means to permit a liquid additive to be injected into the gear pump at the point at which the gear wheels separate. At this point the pressure is at or below atmospheric pressure and, as a result, the additive can be added uniformly and independently of the polymer flow and pressure.