Abstract: Provided is a pressure-sensitive adhesive composition that makes it possible to prevent electrification of a non-antistatic protected material during peeling, is reduced in the risk of staining the protected material, and has good removability, and to provide a pressure-sensitive adhesive layer, a pressure-sensitive adhesive sheet. Specifically provided is a pressure-sensitive adhesive composition which comprises: a (meth)acryl-based polymer including, as a main component, a (meth)acryl-based monomer component having an alkyl group of 1 to 14 carbon atoms; an alkali metal salt; and an organopolysiloxane having a polyoxyalkylene side chain, wherein the (meth)acryl-based polymer has an acid value of 1.0 or less, and the total amount of the alkali metal salt and the organopolysiloxane is from 0.15 to 4 parts by weight, based on 100 parts by weight of the (meth)acryl-based polymer.

Abstract: A pressure-sensitive adhesive composition includes: 100 parts by mass of a polymer (A) (Tg:lower than 0° C.); 0.05 to 3 parts by mass of a (meth)acrylic polymer (B) (MWB:1000?MWB<50000, Tg:30 to 300° C.); and an organopolysiloxane compound (C) having a polyoxyalkylene chain, represented by any one of the following general formulae (C1) to (C3). [In (C1) to (C3), R1 is a monovalent organic group, each of R2 to R4 is an alkylene group, R5 is a hydrogen or an organic group, and each of a and b is an integer of 0 to 1000 (however, they are not 0 at a time); In (C1), each of m and n is an integer of 0 to 1000 (however, they are not 0 at a time); and In (C2) and (C3), m is an integer of 1 to 2000.

Abstract: An acrylic pressure-sensitive adhesive composition for optical use includes: an acrylic polymer (A) that contains, as a monomer unit, a vinyl monomer having a nitrogen atom in its backbone and that does not substantially contain a carboxyl group-containing monomer; and a (meth)acrylic polymer (B) having a weight average molecular weight of 1000 or more and less than 30000.

Abstract: Provided is a pressure-sensitive adhesive composition having antistatic properties that suppresses peeling electrification voltage when peeled off from a non-antistatic adherend, low adhesive strength at high peeling speeds, adhesive strength high enough to prevent problems such as lifting and unintended separation at low peeling speeds, and an optical film to which a pressure-sensitive adhesive sheet, a surface protective sheet, and a surface protective sheet are attached, each sheet having high transparency. A pressure-sensitive adhesive composition, comprising: 100 parts by mass of a polymer (A) with a glass transition temperature of less than 0° C.; 0.1 to 20 parts by mass of a polymer (B) having a weight average molecular weight of 1,000 or more to less than 100,000 and containing a monomer unit derived from a monomer having a nitrogen-containing structure; and 0.1 to 20 parts by mass of an acidic compound (C) with a pKa of ?12.0 or more to less than 3.5.

Abstract: Provided are a pressure-sensitive adhesive sheet that has an antistatic property; suppresses a peeling electrification voltage when a non-antistatic treated adherend is peeled off; has a small adhesive strength occurring at high-speed peeling; has an adhesive strength occurring at low-speed peeling so large as not to cause a problem, such as lifting and peeling off; and has an excellent transparency; and a pressure-sensitive adhesive composition capable of obtaining an optical film to which the pressure-sensitive adhesive sheet is bonded. Disclosed is a pressure-sensitive adhesive composition containing a polymer (A) having a glass transition temperature of lower than 0° C. and a polymer (B) containing a reactive ionic liquid as a monomer unit and having an intrinsic viscosity (dL/g) of 0.01 or more and less than 0.5.

Abstract: Provided is an antistatic pressure-sensitive adhesive sheet and an optical film, excellent in antistatic properties, adhesive properties, heat resistance, and low staining properties, and capable of preventing adhesion of dirt and dust in particular and destruction of electronic components due to static electricity. Disclosed is an antistatic pressure-sensitive adhesive sheet having an antistatic substrate film; and a pressure-sensitive adhesive layer on at least one side of the antistatic substrate film, wherein the pressure-sensitive adhesive layer is formed of an antistatic pressure-sensitive adhesive composition containing a (meth)acrylic-based polymer containing a reactive ionic liquid as a monomer unit.

Abstract: A pressure-sensitive adhesive composition includes: 100 parts by mass of a polymer (A) having a glass transition temperature lower than 0° C.; 0.05 parts by mass to 3 parts by mass of a (meth)acrylic polymer (B) having a weight average molecular weight (MwB) of 1000?MwB<30000 and including, as a monomer unit, a (meth)acrylic monomer having an alicyclic structure represented by the following general formula (1); 0.005 parts by mass to 1 part by mass of an ionic compound (C); and 0.01 parts by mass to 2.5 parts by mass of a compound (D) having a polyoxyalkylene chain. CH2?C(R1)COOR2??(1) [wherein R1 is a hydrogen atom or a methyl group and R2 is an alicyclic hydrocarbon group having an alicyclic structure.

Abstract: An acrylic pressure-sensitive adhesive composition contains 100 parts by mass of an acrylic polymer (A), 1 to 70 parts by mass of a (meth)acrylic polymer (B) having a weight average molecular weight (Mw) of 1000?Mw<30000, and 1 to 50 parts by mass of a hydrogenated tackifying resin (C). The (meth)acrylic polymer (B) is a polymer having a weight average molecular weight smaller than that of the acrylic polymer (A) as a pressure-sensitive adhesive composition, and functions as a tackifying resin along with the hydrogenated tackifying resin (C).

Abstract: A surface protective film that exhibits superior adhesiveness to an adherend and exhibits only small differences in peel strength according to the surface state of an adherend is provided. The surface protective film 10 is provided with an acrylic pressure-sensitive adhesive (PSA) layer 2 on one side of a support 1, and satisfies the following conditions: a thickness reduction ratio (indentation strain E1) when a compressive stress of 0.195 MPa is applied for 10 minutes to a laminate 20 obtained by laminating 24 of the protective films 10 is 7.0% or more, and a ratio (E1/E2) of E1 to a thickness reduction ratio (permanent strain) E2 that remains 10 minutes after the stress is released is 30 or less; and a peel strength S1 on a plain TAC polarizing plate is two times or less a peel strength S2 on a TAG polarizing plate that has been subjected to AG treatment.

Abstract: A pressure-sensitive adhesive composition includes: 100 parts by mass of a polymer (A) having a glass transition temperature lower than 0° C.; and 0.05 parts by mass to 20 parts by mass of a (meth)acrylic polymer (B) having a weight average molecular weight (MwB) of 1000?MwB<30000 that contains, as monomer units, both a (meth)acrylic monomer having an alicyclic structure represented by the following general formula (1) and a monomer having a polyoxyalkylene skeleton: CH2?C(R1)COOR2??(1) [wherein R1 represents a hydrogen atom or a methyl group and R2 represents an alicyclic hydrocarbon group having an alicyclic structure.

Abstract: The present invention relates to an optical acrylic pressure-sensitive adhesive composition, containing: 100 parts by mass of an acrylic polymer (A) which contains a vinylic monomer having a nitrogen atom in a skeleton thereof as a monomer unit and does not substantially contain a monomer containing a carboxyl group; 1-70 parts by mass of a (meth)acrylic polymer (B) having a weight average molecular weight of 1,000 or greater and less than 30,000; and 1-50 parts by mass of a hydrogenated tackifying resin (C), and an optical acrylic pressure-sensitive adhesive tape including a pressure-sensitive adhesive layer containing the optical acrylic pressure-sensitive adhesive composition.

Abstract: An acrylic pressure-sensitive adhesive tape includes a core layer and a surface layer provided on one or both surfaces of the core layer. The core layer contains an acrylic polymer (A). The surface layer contains 100 parts by mass of an acrylic polymer (B) and 1 to 70 parts by mass of a (meth)acrylic polymer (C) that has a weight average molecular weight of 1000 or more and less than 30000 and that has a terpene structure in its side chain. The (meth)acrylic polymer (C) is a polymer having a weight average molecular weight smaller than that of the acrylic polymer (B) as a pressure-sensitive adhesive composition and functions as a tackifying resin.

Abstract: A peelable pressure-sensitive adhesive composition includes: 100 parts by mass of a polymer (A) having a glass transition temperature lower than 0° C.; and 0.05 parts by mass to 3 parts by mass of a (meth)acrylic polymer (B) that has a weight average molecular weight of 1000 or more and less than 30000 and that contains, as a monomer unit, a (meth)acrylic monomer having an alicyclic structure represented by the following general formula (1): CH2?C(R1)COOR2??(1) [wherein, R1 is a hydrogen atom or methyl group and R2 is an alicyclic hydrocarbon group having an alicyclic structure].

Abstract: Provided are a pressure-sensitive adhesive composition that prevents static buildup on the non-antistatic adherend when peeled off, suppresses peeling electrification voltage, is reduced in the risk of staining the adherend, and has a high level of adhesion reliance and re-peeling properties without causing lifting or peeling; an antistatic pressure-sensitive adhesive sheet produced therewith; and a surface protecting film produced therewith. The pressure-sensitive adhesive composition includes (a) a (meth)acryl-based polymer containing, as a monomer unit, 0.01 to 20% by weight of a reactive surfactant; (b) another (meth)acryl-based polymer free of the reactive surfactant; and an ionic compound.

Abstract: An acrylic pressure-sensitive adhesive composition for optical use includes: an acrylic polymer (A) that contains, as a monomer unit, a vinyl monomer having a nitrogen atom in its backbone and that does not substantially contain a carboxyl group-containing monomer; and a (meth)acrylic polymer (B) having a weight average molecular weight of 1000 or more and less than 30000.

Abstract: The present invention relates to an optical acrylic pressure-sensitive adhesive composition, containing: 100 parts by mass of an acrylic polymer (A) which contains a vinylic monomer having a nitrogen atom in a skeleton thereof as a monomer unit and does not substantially contain a monomer containing a carboxyl group; 1-70 parts by mass of a (meth)acrylic polymer (B) having a weight average molecular weight of 1,000 or greater and less than 30,000; and 1-50 parts by mass of a hydrogenated tackifying resin (C), and an optical acrylic pressure-sensitive adhesive tape including a pressure-sensitive adhesive layer containing the optical acrylic pressure-sensitive adhesive composition.

Abstract: A transparent film whose back-face has excellent resistance to scratch, and a surface protection film having the transparent film are provided. A transparent film has a substrate layer formed of a transparent resin material, and a back-face layer with a thickness of 1 ?m or less provided on a first face thereof. In a scratch test of the transparent film, the failure initiation load of the back-face layer is 50 mN or greater and the friction coefficient of the back-face layer is 0.4 or less.

Abstract: The present invention provides a surface protective film that exhibits small differences in peel strength on account of the surface state of an adherend and that is excellent in anti-contamination to adherends, and a pressure-sensitive adhesive (PSA) composition for the protective film. The PSA composition provided by the present invention comprises 0.01 to 5 parts by weight of a compound containing an oxypropylene group with respect to 100 parts by weight of an acrylic polymer as a base polymer. A surface protective film 10 provided by the present invention has a PSA layer 2, formed using the above PSA composition, on one or both sides of a support 1.

Abstract: Provided is a pressure-sensitive adhesive composition that makes it possible to prevent electrification of a non-antistatic protected material during peeling, is reduced in the risk of staining the protected material, and has good removability, and to provide a pressure-sensitive adhesive layer, a pressure-sensitive adhesive sheet. Specifically provided is a pressure-sensitive adhesive composition which comprises: a (meth)acryl-based polymer including, as a main component, a (meth)acryl-based monomer component having an alkyl group of 1 to 14 carbon atoms; an alkali metal salt; and an organopolysiloxane having a polyoxyalkylene side chain, wherein the (meth)acryl-based polymer has an acid value of 1.0 or less, and the total amount of the alkali metal salt and the organopolysiloxane is from 0.15 to 4 parts by weight, based on 100 parts by weight of the (meth)acryl-based polymer.

Abstract: A surface protective film that exhibits superior adhesiveness to an adherend and exhibits only small differences in peel strength according to the surface state of an adherend is provided. The surface protective film 10 is provided with an acrylic pressure-sensitive adhesive (PSA) layer 2 on one side of a support 1, and satisfies the following conditions: a thickness reduction ratio (indentation strain E1) when a compressive stress of 0.195 MPa is applied for 10 minutes to a laminate 20 obtained by laminating 24 of the protective films 10 is 7.0% or more, and a ratio (E1/E2) of E1 to a thickness reduction ratio (permanent strain) E2 that remains 10 minutes after the stress is released is 30 or less; and a peel strength S1 on a plain TAC polarizing plate is two times or less a peel strength S2 on a TAG polarizing plate that has been subjected to AG treatment.