Dispersion of solvent-suspendible pressure sensitive adhesive particles and pressure sensitive adhesive sheet utilizing the properties of the dispersion

A pressure sensitive adhesive sheet prepared by coating a sheet with a dispersion of solvent-suspendible pressure sensitive adhesive particles, which comprises

• (A) pressure sensitive adhesive particles comprising an internally cross-linked copolymer and having a particle size of 5 to 200 microns and
• an organic solvent;
• said internally cross-linked copolymer being prepared by copolymerizing
• (a) 2 to 10% by weight of at least one member selected from the group consisting of methyl acrylate, styrene and a methacrylate of alcohol having 1 to 5 carbon atoms,
• (b) 98 to 90% by weight of at least one member selected from the group consisting of an acrylate of alcohol having 2 to 12 carbon atoms and a methacrylate of alcohol having 6 to 12 carbon atoms,
• (c) 0.1 to 2.0% by weight of maleic anhydride, and
• (d) 0.05 to 1.0% by weight of at least one member selected from the group consisting of tetraallyloxyethane, triallyl cyanurate and triallyl isocyanurate.

A dispersion of solvent-suspendible pressure sensitive adhesive particles, which comprises

• (A) 100 parts by weight of pressure sensitive adhesive particles comprising an internally cross-linked copolymer and having a particle size of 5 to 200 microns,
• (B) 2 to 20 parts by weight (as solid matter) of a binder for said pressure sensitive adhesive particles which is a styrene-containing polymer having a styrene content of 5 to 70% by weight and having a particle size of 0.02 to 3 microns,
• and an organic solvent;
• said internally cross-linked copolymer being prepared by copolymerizing
• (a) 2 to 10% by weight of at least one member selected from the group consisting of methyl acrylate, styrene and a methacrylate of alcohol having 1 to 5 carbon atoms,
• (b) 98 to 90% by weight of at least one member selected from the group consisting of an acrylate of alcohol having 2 to 12 carbon atoms and a methacrylate of alcohol having 6 to 12 carbon atoms,
• (c) 0.1 to 2.0% by weight of maleic anhydride, and
• (d) 0.05 to 1.0% by weight of at least one member selected from the group consisting of tetraallyloxyethane, triallyl cyanurate and triallyl isocyanurate.

A pressure sensitive adhesive sheet prepared by coating a sheet with a dispersion of solvent-suspendible pressure sensitive adhesive particles, which comprises

• (A) 100 parts by weight of pressure sensitive adhesive particles comprising an internally cross-linked copolymer and having a particle size of 5 to 200 microns,
• (B) 2 to 20 parts by weight (as solid matter) of a binder for said pressure sensitive adhesive aprticles which is a styrene-containing polymer having a styrene content of 5 to 70% by weight and having a particle size of 0.02 to 3 microns,
• and an organic solvent;
• said internally cross-linked copolymer being prepared by copolymerizing
• (a) 2 to 10% by weight of at least one member selected from the group consisting of methyl acrylate, styrene and a methacrylate of alcohol having 1 to 5 carbon atoms,
• (b) 98 to 90% by weight of at least one member selected from the group consisting of an acrylate of alcohol having 2 to 12 carbon atoms and a methacrylate of alcohol having 6 to 12 carbon atoms,
• (c) 0.1 to 2.0% by weight of maleic anhydride, and
• (d) 0.05 to 1.0% by weight of at least one member selected from the group consisting of tetraallyloxyethane, triallyl cyanurate and triallyl isocyanurate.