Abstract: A pressure-sensitive adhesive label has a base having an information indication portion on its one surface thereof, and a pressure-sensitive adhesive layer formed on another surface of the base. After peeling a release liner, the label is stuck on an outer surface of a housing of the hard disk drive to reduce noise generated when the hard disk drive is driven. The release liner for coating the pressure-sensitive adhesive layer has an antistatic function and a cut line. The adhesive force of the adhesive layer is reduced by heating. The label has a surface density of not lower than 0.18 (kg/m2).

Abstract: A heat-peelable adhesive sheet which shows small increase in the degree of contamination caused by a heat treatment for lowering an adhesive force is disclosed. The heat-peelable pressure sensitive adhesive sheet comprises a heat-expandable layer containing heat-expandable microspheres and expanding upon heating, and. a non-heat expandable pressure-sensitive adhesive layer formed on at least one side thereof. The heat-peelable pressure-sensitive adhesive sheet can achieve the desired adhesive properties such as an excellent adhesive force before heating and also show a quick lowering of the adhesive force upon heating. Further, it shows small increase in the degree of contamination due to the treatment for lowering the adhesive force. Due to those characteristics, the heat-peelable pressure-sensitive adhesive sheet is practically applicable to, for example, the production of electronic parts made of thinner semiconductor wafers.

Abstract: A radiation-curable heat-peelable pressure-sensitive adhesive sheet is disclosed which has tackiness enabling adherends to withstand transportation and other steps, with which cutting can be conducted without flinging up an adhesive waste or causing chipping, and from which the cut pieces can be easily separated and recovered. The radiation-curable heat-peelable pressure-sensitive adhesive sheet comprises a substrate and, formed on at least one side thereof, a pressure-sensitive adhesive layer containing heat-expandable microspheres and a radiation-curable compound. A work to be cut is placed on the surface of the pressure-sensitive adhesive layer of the radiation-curable heat-peelable pressure-sensitive adhesive sheet, and the pressure-sensitive adhesive layer is irradiated with a radiation to cure the adhesive layer. The work is cut into pieces and the pressure-sensitive adhesive layer is then thermally foamed, before the cut pieces are separated and recovered from the adhesive sheet.

Abstract: A positive photosensitive composition showing a difference in solubility in an alkali developer as between an exposed portion and a non-exposed portion, which comprises, as components inducing the difference in solubility,

Abstract: A positive photosensitive composition showing a difference in solubility in an alkali developer as between an exposed portion and a non-exposed portion, which comprises, as components inducing the difference in solubility, (a) a photo-thermal conversion material, and (b) a high molecular compound, of which the solubility in an alkali developer is changeable mainly by a change other than a chemical change.

Abstract: A heat-peelable pressure-sensitive adhesive sheet which, even when used for temporarily fixing electronic parts having poor resistance to static electricity, such as magnetic heads, is effective in preventing the yield of such electronic parts from being reduced by electrostatic breakage, while ensuring its functions of adhesiveness before heating and peelability after heating. The heat-peelable pressure-sensitive adhesive sheet comprises a substrate and formed on at least one side thereof a heat-expandable pressure-sensitive adhesive layer containing heat-expandable microspheres, wherein the heat-expandable pressure-sensitive adhesive layer has a surface resistivity of 1012 &OHgr;/□ or lower. In this heat-peelable pressure-sensitive adhesive sheet, the heat-expandable pressure-sensitive adhesive layer before heating may have a center line average surface roughness of 2 &mgr;m or less and a maximum surface roughness of 5 &mgr;m or less.

Abstract: A positive photosensitive composition showing a difference in solubility in an alkali developer as between an exposed portion and a non-exposed portion, which comprises, as components inducing the difference in solubility, (a) a photo-thermal conversion material, and (b) a high molecular compound, of which the solubility in an alkali developer is changeable mainly by a change other than a chemical change.

Abstract: A radiation-curable heat-peelable pressure-sensitive adhesive sheet is disclosed which has tackiness enabling adherends to withstand transportation and other steps, with which cutting can be conducted without flinging up an adhesive waste or causing chipping, and from which the cut pieces can be easily separated and recovered. The radiation-curable heat-peelable pressure-sensitive adhesive sheet comprises a substrate and, formed on at least one side thereof, a pressure-sensitive adhesive layer containing heat-expandable microspheres and a radiation-curable compound. A work to be cut is placed on the surface of the pressure-sensitive adhesive layer of the radiation-curable heat-peelable pressure-sensitive adhesive sheet, and the pressure-sensitive adhesive layer is irradiated with a radiation to cure the adhesive layer. The work is cut into pieces and the pressure-sensitive adhesive layer is then thermally foamed, before the cut pieces are separated and recovered from the adhesive sheet.

Abstract: A positive photosensitive composition comprising an alkali-soluble resin having phenolic hydroxyl groups (a) and a photo-thermal conversion material (b), and not containing a quinonediazide compound, which contains an alkali-soluble resin having phenolic hydroxyl groups, of which at least some are esterified (a-1).

Abstract: A positive photosensitive composition comprising at least (a) an alkali-soluble resin and (b) a photo-thermal conversion material, which further contains (c) a compound capable of crosslinking the alkali-soluble resin by a thermal action, and which contains substantially no compound which has a function to generate an acid when exposed in the coexistence of the photo-thermal conversion material.

Abstract: A photosensitive composition comprising (1) a compound having at least one addition-polymerizable ethylenically unsaturated double bond, (2) an acidic vinyl copolymer soluble or swellable in alkaline water, which contains, in its molecule, a vinyl monomer having an aromatic hydroxyl group, as a constituting unit, (3) a photopolymerization initiator, and (4) a diazo resin, wherein the diazo resin is a copolycondensed compound which contains, in its molecule, an aromatic compound having a carboxyl group and/or a hydroxyl group, and an aromatic diazonium compound, as constituting units.

Abstract: A photosensitive composition comprising(a) a resin selected from the group consisting of novolak resins and polyvinylphenol resins;(b) an amino compound derivative capable of curing the resin;(c) at least one member selected from the group consisting of cyanine compounds of the following formula (I) and polymethine compounds of the following formula (II), as a compound showing absorption in a near infrared wavelength region: ##STR1## (d) a photosensitive acid-forming agent.

Abstract: A photopolymerizable composition comprising an addition polymerizable compound having at least one ethylenically unsaturated double bond and a photopolymerization initiator system, wherein the photopolymerization initiator system comprises:(a) a titanocene compound, and(b) at least one coumarin compound of the following formula (I): ##STR1## wherein (i) each of R.sup.1, R.sup.2 and R.sup.5 is a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group, each of R.sup.3 and R.sup.4 is an alkyl group, provided that at least one of R.sup.3 and R.sup.4 is a C.sub.4-16 alkyl group, or (ii) R.sup.1 is a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group, and at least one set of R.sup.2 and R.sup.3, and R.sup.4 and R.sup.5, is connected to form an alkylene group substituted by a lower alkyl group, provided that when they do not form the connecting group, each of R.sup.2 and R.sup.5 is a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group, and each of R.sup.3 and R.sup.

Abstract: Disclosed is a light-sensitive composition which comprises(A) a diazo resin and(B) an alkali-soluble and swellable polymer compound, said polymer compound being a vinyl copolymer containing, as a constitutional unit, 0.1 to 10 mole % of a structure derived from an ester of acrylic acid or methacrylic acid having an alkyl group with 8 or more carbon atoms.

Abstract: An expoxy resin composition, an epoxy resin cured product obtained therefrom, and a bonding method using the composition are disclosed. The epoxy resin composition comprises an epoxy resin composition comprising (A) 100 parts by weight of an epoxy resin, (B) from 1 to 80 parts by weight of a heat activatable hardener, and (C) from 10 to 100 parts by weight of an aromatic thermoplastic resin powder having a glass transition temperature of 120.degree. C. or more and an average particle diameter of 200 .mu.m or less, said components (A), (B) and (C) being present in a phase separation state.