Provided is an optical PSA composition that can be easily peeled using an aqueous liquid such as water and has sufficient adhesive strength. An optical PSA composition comprising an acrylic polymer is provided. The PSA composition comprises at least one species of compound A selected among surfactants and compounds having polyoxyalkylene backbones. The monomers forming the acrylic polymer comprises less than 20 wt % alkoxyalkyl (meth)acrylate and less than 20 wt % alkoxypolyalkylene glycol (meth)acrylate. Alternatively, the compound A content is less than 1 part by weight to 100 parts by weight of the acrylic polymer.

Compositions are disclosed which include between about 0.05 to about 5 or less wt. % of at least one acrylate monomer based on the total weight of the composition. The acrylate monomer reduces the peak cure temperature, thereby accelerating the rate of cure, without sacrificing completeness of the cure or the release performance of the cured product. The addition of the acrylate monomer also enables a reduction in the amount of costly platinum catalyst required to effectively cure a composition. In addition to the acrylate monomer, the compositions also include a silicone base polymer, a crosslinking agent, and platinum catalyst. The cured compositions exhibit properties useful for incorporation into release liners, adhesive articles, medical products and gaskets.

Described are methods for processing microelectronic device substrates by a lapping step, e.g., a final lapping step, wherein the step includes the use of an elastomeric pressure-sensitive adhesive to secure the microelectronic device substrate to a carrier that holds the substrate to a surface of the carrier during the lapping step, and wherein the pressure-sensitive adhesive can be a non-polysilicone based adhesive having mechanical properties that include a tan delta that is below about 0.2.

A tackifier composition comprising at least one thermoplastic hydrocarbon resin and an antioxidant composition is provided; wherein a portion of the volatile organic compounds in the thermoplastic hydrocarbon resin has been removed; wherein the antioxidant composition comprises at least one primary antioxidant and at least one secondary antioxidant; and wherein the levels of individual volatile organic compound monitored in the tackifier composition are less than about 0.5 ppm as measured by GC/MS headspace analysis. Processes for producing the tackifier composition are also provided as well as adhesives comprising the tackifier compositions.

Silicone polyoxamide and silicone polyoxamide-hydrazide copolymers comprise at least two repeating units of formula (I). In this formula, each R.sup.1 is independently an alkyl, haloalkyl, aralkyl, alkenyl, aryl, or aryl substituted with an alkyl, alkoxy, or halo; each Y is independently an alkylene, aralkylene, or a combination thereof; each G is independently a bond or a divalent residue equal to a diamine of formula R.sup.3HN—G—HR.sup.3 minus the two —NHR.sup.3 groups; each R.sup.3 is independently hydrogen or alkyl or R.sup.3 taken together with G and with the nitrogen to which they are both attached form a heterocyclic group; each n is independently an integer of 0 to 300; each p is independently an integer of 1 to 25, and the average of p is 1.3 or greater; and each q is independently an integer of 1 to 2, and the average of q is no greater than 1.05.

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Described are methods for processing microelectronic device substrates by a lapping step, e.g., a final lapping step, wherein the step includes the use of an elastomeric pressure-sensitive adhesive to secure the microelectronic device substrate to a carrier that holds the substrate to a surface of the carrier during the lapping step, and wherein the pressure-sensitive adhesive can be a non-polysilicone based adhesive having mechanical properties that include a tan delta that is below about 0.2.

An aqueous dispersion including a hydroxyl-terminated urethane prepolymer obtained by reacting an oxyalkylene polymer A in which an average number of hydroxyl groups per molecule is more than 2.0 and 3.0 or less, an oxyalkylene polymer B in which an average number of hydroxyl groups per molecule is 1.2 or more and 2.0 or less, and a diisocyanate compound, where a content proportion of oxyethylene groups to a total amount of oxyalkylene groups in the oxyalkylene polymer A is 15% by mass or more, a content proportion of oxyethylene groups to a total amount of oxyalkylene groups in the oxyalkylene polymer B is 15% by mass or more, and a content proportion of oxyethylene groups to a total amount of oxyalkylene groups in the hydroxyl-terminated urethane prepolymer is more than 20% by mass and 70% by mass or less.

(Meth)acrylate-functionalized oligomers having a) an oligomeric backbone comprised of first segments and second segments and b) (meth)acrylate-functionalized end groups are provided. Such oligomers are useful as components of curable compositions. The first segments, second segments and (meth)acrylate-functionalized end groups are linked together by linking moieties derived from a polyisocyanate. The first segments are residues of a first segment precursor containing a plurality of repeating units and a plurality of isocyanate-reactive functional groups and having a number average molecular weight of at least 250 daltons. The second segments are residues of a second segment precursor, different from the first segment precursor, containing a plurality of repeating units and a plurality of isocyanate-reactive functional groups and having a number average molecular weight of at least 250 daltons. The first segment and the second segment exhibit a Hansen Solubility Parameter Distance Relative Energy Difference of at least about 4 and not more than about 9.

Provided is a PSA sheet having a PSA layer. The PSA layer has a multilayer structure comprising a layer A forming one face of the PSA layer and a layer B placed on the backside of the layer A. The layer B is a photo-crosslinkable PSA layer comprising a photo-crosslinkable polymer.

Pressure sensitive adhesive (PSA) compositions that include at least one urethane (meth)acrylate oligomer having a molecular weight between about 2,000 g/mol and about 50,000 g/mol and an OH number of from 0.01 mg KOH/g to 100 mg KOH/g, at least one mono (meth)acrylate functional monomer and at least one tackifying resin. The PSA systems may also optionally include other additives, such as at least one initiator system that includes at least one photo-initiator or free radical initiator. The PSA systems are liquid at a temperature of 25° C.±2° C. with a viscosity of 15,000 cPs or less and are adapted to form smooth, uniform coatings or films upon curing without the application of heat, whereby the resulting films have advantageous properties with respect to peel strength, tack and shear resistance. In embodiments, the PSA systems include less than 1 wt % of solvent and less than 1 wt % of water or are free of solvent and are free of water.