Abstract:
The present invention relates to a method for thermal crosslinking of adhesives and also to products produced with these adhesives. An object of the invention is to provide a method for thermal crosslinking of adhesives where the crosslinking is covalent and (initiated by a chemical or physical stimulus) reversible. As and when required, the crosslinking method can also be configured to result in a covalent, irreversible network.
Abstract:
A resist composition which can easily form a resist pattern excellent in transparency for vacuum ultraviolet rays such as an F2 excimer laser or the like and dry etching characteristics and further excellent in sensitivity, resolution, flatness, thermal resistance and the like, is provided. The resist composition, characterized by comprising (A) a fluorine-containing polymer having an acidic group blocked with a blocking group containing a cycloalkyl group, an organic group having one or more of cycloalkyl groups, a bicycloalkyl group or the like, (B) an acid generating compound capable of generating an acid by irradiation with a light, and (C) an organic solvent.
Abstract:
Polymers having an average molecular weight M.sub.w (weight average) of 5,000 to 1,000,000 (measured by gel permeation chromatography), comprising structural repeating units of the formulae I-IV: ##STR1## in which R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.7, R.sub.8, R.sub.9 and R.sub.10 and w, x, y, and z are defined herein, are suitable as binders for DUV photoresists of high processing stability and flow resistance.
Abstract:
Resin compositions, melt-extruded articles, oriented articles and packaging materials for foods obtained from these articles are disclosed. The resin composition includes: (a) from 40 to 80% by weight of a PVA (A) having a degree of saponification of from 60 to 95 mole % by weight, (b) from 5 to 40% by weight of EVOH (B), (c) from 1 to 15% by weight of a thermoplastic resin (C) having a softening temperature not higher than 130.degree. C. and (d) from 5 to 15% by weight of a PEG (D), the total of (A), (B), (C) and (D) being 100% by weight.
Abstract:
Holographic films contain a copolymer binder having the following formula:(M).sub.w (VAc).sub.x (VOH).sub.y (CTFE).sub.zwherein M is a fluoromonomer; VAc is vinyl acetate; VOH is vinyl alcohol; and CTFE is chlorotrifluoroethylene; and wherein w, x, y, and z are percentages by weight; w is 5 to 22%, x is 50 to 75%, y is 3 to 8%, and z is 15 to 30% with the copolymer containing 3-35% by weight fluorine. These imaged films are particularly suited for lamination to glass in head-up display applications.
Abstract:
Metallic, ash-producing residues which remain in poly(vinyl alcohol) polymer after its preparation from poly(vinyl acetate) are removed by a process which involves contacting a slurry of the poly(vinyl alcohol) polymer, after preparation and before polymer isolation, with ion-exchange resin particles, followed by removal of the ion-exchange resin particles from the poly(vinyl alcohol) polymer particles utilizing size or weight differences between them. The poly(vinyl alcohol) polymer remains in the solid state throughout, avoiding dissolution and the need for re-precipitation.
Abstract:
The invention relates to an object and a process for the preparation of an object from an ethylene-vinyl alcohol copolymer with high tensile strength and modulus, by converting:a) a solution of an ethylene-vinyl alcohol copolymer with a weight-average molecular weight above 6.times.10.sup.4 kg/Kmole into a shaped, solvent-containing object in a suitable solvent or mixture of solvents;b) converting this object into a gel object with a homogeneous gelstructure by rapid cooling to below the gelation temperature;c) removing the solvent present in this gel object for the most partd) Drawing the gel object during or after solvent removal at a temperature above the glass transition temperature but below the melting temperature of the copolymer.
Abstract:
A linear addition polymer having sidegroups which may be coupled to it or not through a spacer and have a molecular hyperpolarizability .beta. of at least 10.sup.-38 m.sup.4 /V, characterized in that the recurring units of the polymer correspond to the formula ##STR1## wherein X represents a hydrogen atom or a lower alkyl group and m=1 or optionally 0, wherewhen m-1Y represents a ##STR2## group and R has the meaning of (a) a hyperpolarizable group having a molecular hyperpolarizability .beta. of at least 10.sup.-38 m.sup.4 /V, in the presence or not of a spacer, and optionally along with(b) a mesogenic group in the presence or not of a spacer, and/or(c) a hydrogen atom or a substituted or unsubstituted organic group having not more than 30 carbon atoms, andwhen m=0Y represents a --CN, a substituted or unsubstituted phenyl group or a group of the formula --OR.sub.1 or --CH.sub.2 OR.sub.1, wherein R.sub.1 has the meaning of a hydrogen atom or a substituted or unsubstituted aliphatic group having not more than 20 carbon atoms, provided thatat least 10% of the recurring units in the polymer contain a hyperpolarizable group having a molecular hperpolarizability .beta. of at least 10.sup.-38 m.sup.4 /V,at the most 40% of the recurring units in the polymer contain a mesogenic group, andthat the quotient of the degree of substitution of the recurring units with a group having a molecular hyperpolarizability .beta. of at least 10.sup.-38 m.sup.4 /V and the average molecular weight of R with the meaning given under b and c amounts to at least 5.times.10.sup.-4, a non-linear optical medium thereof oriented in an electric field and electro-optical laminates comprising such a non-linear optical medium.
Abstract:
The present invention relates to a method of producing polyvinyl alcohol hydrogel characterized by the following features: the production process consists of a low-temperature processing stage in which the solution of polyvinyl alcohol with a polymerization degree over 1200 is processed at a low temperature so that polyvinyl alcohol is gelated, and a high-temperature processing stage in which the polyvinyl alcohol gelated int he low-temperature processing stage is dried, then processed at higher than 100.degree. C.; in this way, polyvinyl alcohol hydrogel with a saturated water content lower than 40 wt % is obtained. The hydrogels of this invention are useful for providing improved artificial articular cartilage for replacement of cartilage in the human body.
Abstract:
A contact lens of a crosslinked, organic aprotic solvent insoluble, substantially transparent polymer of a derivative of a polyvinyl alcohol having a weight average molecular weight of at least about 2,000, containing an effective amount between about 0.1 to 90 percent, based on the number of hydroxyl groups on said polyvinyl alcohol, of a crosslinked addition reaction product of units of the formula ##STR1## in the presence or absence of a polymerizable vinylic monomer whereinR.sub.1 is a divalent aliphatic, cycloaliphatic, arylene, aralkylene, alkarylene or heterocyclic group;A is --O--, --NH-- or ##STR2## where R" is hydrogen or lower alkyl and A' is a direct bond or A is a direct bond and A' is --O-- or --O--CH.sub.2 --;R.sub.2 is hydrogen or methyl; andR.sub.3 is hydrogen, methyl or --COOR.sub.4 where R.sub.4 is hydrogen or lower alkyl with the proviso that if R.sub.2 is methyl, R.sub.3 is hydrogen.