Removable pressure sensitive adhesive

Claim 2

In an acrylate based pressure sensitive emulsion adhesive having a Tg of about -60° to about -20° C. the improvement which comprises polymerizing therein an effective amount of an organofunctional silane monomer thereby improving the removability of the adhesive.

Claim 3

The adhesive of claim 1 wherein the organofunctional silane monomer added in an amount of 0.01 to 0.5% by weight of the solids of the emulsion adhesive.

Claim 4

The adhesive of claim 1 wherein the organofunctional silane monomer is a vinyl or mercapto-substituted silane.

Claim 5

The adhesive of claim 3 wherein the organofunctional silane monomer is selected from the group consisting of vinyltrichlorosilane, vinyltriethoxysilane, vinyltrimethoxysilane, vinyltris(2-methoxyethoxy)silane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltris(2-methoxyethoxy)silane, vinyltriacetoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 4-(3-trimethoxysilylpropyl)benzylstyrene sulfonate, 3-acryloxypropyltrimethoxysilane, allyltriethoxysilane, allyltrimethoxysilane, vinylmethyldiethoxysilane, vinyldimethylethoxysilane, vinylmethyldiacetoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyldimethylethoxysilane, and 3-acryloxypropyldimethylmethoxysilane.

Claim 6

The adhesive of claim 4 wherein the organofunctional silane monomer is selected from the group consisting of vinyltrichlorosilane, vinyltriethoxysilane, vinyltrimethoxysilane, vinyltris(2-methoxyethoxy)silane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltris(2-methoxyethoxy)silane, vinyltriacetoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 4-(3-trimethoxysilylpropyl)benzylstyrene sulfonate, 3-acryloxypropyltrimethoxysilane, allyltriethoxysilane, and allyltrimethoxysilane.

Claim 7

The adhesive of claim 1 wherein the organofunctional silane monomer is selected from this group consisting of silane monomer are 3-glycidoxypropyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-epoxy-4-methylcyclohexyl)propylmethyldiethoxysilane, 3-glycidoxypropyldimethylethoxysilane, and 3-glycidoxypropylmethyldiethoxysilane.

Claim 8

The adhesive of claim 1 wherein the pressure sensitive emulsion adhesive comprises at least about 30% by weight of an acrylate polymer prepared from alkyl acrylates having an average of from 3 to 10 carbon atoms in the alkyl group.

Claim 9

The adhesive of claim 7 wherein at least about 60% by weight of the acrylate polymer is prepared from alkyl acrylates having an average of from 3 to 10 carbon atoms in the alkyl group.

Claim 10

The adhesive of claim 8 wherein the pressure sensitive emulsion adhesive comprises an interpolymer of 2-ethylhexyl, iso-octyl or butyl acrylate with methyl methacrylate.

Claim 11

The adhesive of claim 8 wherein the pressure sensitive emulsion adhesive comprises an interpolymer of 2-ethylhexyl, iso-octyl or butyl acrylate with vinyl acetate.

Claim 12

A substrate having coated thereon the removable pressure sensitive adhesive of claim 1.

Claim 13

A substrate having coated thereon the removable pressure sensitive adhesive of claim 4.

Claim 14

In a process for the preparation of an acrylate based pressure sensitive emulsion adhesive having a Tg of about -60° to about -20° C. the improvement which comprises the step of polymerizing therein an effective amount of an organofunctional silane monomer thereby improving the removability of the adhesion.

Claim 15

In a process for the preparation of an acrylate based pressure sensitive emulsion adhesive having a Tg of about -60° to about -20° C. the improvement which comprises the step of polymerizing therein an effective amount of an organofunctional silane monomer thereby improving the removability of the adhesion.

Claim 16

The process of claim 13 wherein wherein the organofunctional silane monomer is added in an amount of 0.01 to 0.5% by weight of the solids of the emulsion adhesive.

Claim 17

The process of claim 13 wherein the organofunctional silane monomer is a vinyl or mercapto-substituted silane.

Claim 18

The process of claim 13 wherein the organofunctional silane monomer is selected from the group consisting of vinyltrichlorosilane, vinyltriethoxysilane, vinyltrimethoxysilane, vinyltris(2-methoxyethoxy)silane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltris(2-methoxyethoxy)silane, vinyltriacetoxysilane and 3-mercaptopropyltrimethoxysilane 3-mercaptopropyltriethoxysilane, 4-(3-trimethoxysilylpropyl)benzylstyrene sulfonate, 3-acryloxypropyltrimethoxysilane, allyltriethoxysilane, allyltrimethoxysilane, vinylmethyldiethoxysilane, vinyldimethylethoxysilane, vinylmethyldiacetoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyldimethylethoxysilane, and 3-acryloxypropyldimethylmethoxysilane.

Claim 19

The process of claim 16 wherein the organofunctional silane monomer is selected from the group consisting of vinyltrichlorosilane, vinyltriethoxysilane, vinyltrimethoxysilane, vinyltris(2-methoxyethoxy)silane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltris(2-methoxyethoxy)silane, vinyltriacetoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 4-(3-trimethoxysilylpropyl)benzylstyrene sulfonate, 3-acryloxypropyltrimethoxysilane, allyltriethoxysilane, and allyltrimethoxysilane.

Claim 20

The process of claim 13 wherein the organofunctional silane monomer is selected from this group consisting of 3-glycidoxypropyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-epoxy-4-methylcyclohexyl)propylmethyldiethoxysilane, 3-glycidoxypropyldimethylethoxysilane, and 3-glycidoxypropylmethyldiethoxysilane.

Claim 21

The process of claim 13 wherein the pressure sensitive emulsion adhesive comprises at least about 30% by weight of an acrylate polymer prepared from alkyl acrylates having an average of from 3 to 10 carbon atoms in the alkyl group.