Pressure-sensitive adhesive and disposable diaper closure system

Claim 2

A pressure-sensitive adhesive composition comprising a functional adhesive mixture of; 30 to 60 weight percent of an elastomeric component consisting essentially of 4 to 55 percent polyisoprene having a number average molecular weight of greater than 100,000 and 45 to 96 percent of an AB(A) block copolymer wherein the A block is 10 to 50 percent of the copolymer and comprises a ring alkylated styrene or styrene and the B block is derived primarily from isoprene, said block copolymer comprising less than 95 weight percent diblock copolymer, and 70 to 40 weight percent of a tackifying component comprising solid tackifying resin, solid tackifying resin with a liquid tackifying resin or plasticizing oil, or a solid tackifying resin with liquid tackifying resin and plasticizing oil so as to provide an adhesive mixture having a composite midblock glass transition temperature in the range of 240 to 270 Kelvin.

Claim 3

The pressure-sensitive adhesive of claim 1 wherein the polyisoprene has a number average molecular weight greater than 200,000.

Claim 4

The pressure-sensitive adhesive of claim 1 wherein the polyisoprene comprises 20 to 50 percent of the elastomeric component.

Claim 5

The pressure-sensitive adhesive of claim 1 wherein the polyisoprene comprises 30 to 45 percent of the elastomeric component.

Claim 6

The pressure-sensitive adhesive of claim 1 wherein the polyisoprene comprises 30 to 50 percent of the elastomeric component, the block copolymer is a linear block copolymer comprised predominantly of diblock and triblock species, the A block has an average molecular weight between 4,000 and 50,000, and the B block has an average molecular weight between about 5,000 and 500,000.

Claim 7

The pressure-sensitive adhesive of claim 1 wherein the elastomeric component comprises 35 to 55 weight percent of the functional adhesive mixtures and the tackifying component comprises 45 to 65 weight percent of the functional adhesive mixture.

Claim 8

The pressure-sensitive adhesive of claim 6 wherein 25 to 60 weight percent of the functional adhesive mixture is a solid tackifying resin and 0 to 30 weight percent of the functional adhesive mixture is selected from the group consisting of liquid tackifying resin and plasticizing oil.

Claim 9

The pressure-sensitive adhesive of claim 7 wherein the tackifying resin is compatible with the polyisoprene components of the adhesive, and the composite midblock glass transition temperature of the adhesive is from 245 to 255 Kelvin.

Claim 10

The pressure-sensitive adhesive of claim 8 wherein the tackifying resin is selected from the group consisting of aliphatic hydrocarbon resins, mixed aliphatic/aromatic tackifying resins, polyterprene tackifiers and hydrogenated tackifying resins, and the block copolymer percent diblock is less than 85 percent.

Claim 11

The pressure-sensitive adhesive of claim 8 where the plasticizing oil is selected from the group consisting of naphthionic oil and aromatic oils, and the block copolymer percent diblock is less than 75 percent.

Claim 12

The pressure-sensitive adhesive of claim 6 wherein 30 to 55 weight percent of the functional adhesive mixture is a solid tackifying resin and 5 to 20 weight percent of the functional adhesive mixture is selected from the group consisting of liquid tackifying resin and plasticizing oil.

Claim 13

The pressure-sensitive adhesive of claim 6 wherein 25 to 60 weight percent of the functional adhesive mixture is a solid tackifying resin and 5 to 20 weight percent of the functional adhesive mixture is selected from the group consisting of liquid tackifying resin and plasticizing oil.

Claim 14

The pressure-sensitive adhesive of claim 1 wherein 25 to 60 weight percent of the functional adhesive mixture is a solid tackifying resin and 0 to 30 weight percent of the functional adhesive mixture is liquid tackifying resin or plasticizing oil.

Claim 15

A pressure-sensitive adhesive tape comprising a backing and coated onto said backing an adhesive layer of a functional adhesive mixture of; 30 to 60 weight percent of an elastomeric component consisting essentially of 4 to 55 percent polyisoprene having a number average molecular weight of greater than 100,000 and 96 to 45 percent of an AB(A) block copolymer wherein the A block is 10 to 50 percent of the copolymer and comprises a ring alkylated styrene or styrene and the B block is derived primarily from isoprene, said block copolymer comprising less than 95 weight percent diblock copolymer, and 40 to 70 weight percent of a tackifying component comprising solid tackifying resin, solid tackifying resin with a liquid tackifying resin or plasticizing oil, or solid tackifying resin with liquid tackifying resin and plasticizing oil so as to provide an adhesive mixture having a composite midblock glass transition temperature in the range of 240 to 270 Kelvin.

Claim 16

A pressure-sensitive adhesive tape comprising a backing and coated onto said backing an adhesive layer of a functional adhesive mixture of; 30 to 60 weight percent of an elastomeric component consisting essentially of 4 to 55 percent polyisoprene having a number average molecular weight of greater than 100,000 and 96 to 45 percent of an AB(A) block copolymer wherein the A block is 10 to 50 percent of the copolymer and comprises a ring alkylated styrene or styrene and the B block is derived primarily from isoprene, said block copolymer comprising less than 95 weight percent diblock copolymer, and 40 to 70 weight percent of a tackifying component comprising solid tackifying resin, solid tackifying resin with a liquid tackifying resin or plasticizing oil, or solid tackifying resin with liquid tackifying resin and plasticizing oil so as to provide an adhesive mixture having a composite midblock glass transition temperature in the range of 240 to 270 Kelvin.

Claim 17

The pressure-sensitive adhesive tape of claim 14 wherein the polyisoprene has a number average molecular weight greater than 200,000.

Claim 18

The pressure-sensitive adhesive tape of claim 14 wherein the polyisoprene comprises 20 to 50 percent of the elastomeric component.

Claim 19

The pressure-sensitive adhesive tape of claim 14 wherein the polyisoprene comprises 30 to 45 percent of the elastomeric component.

Claim 20

The pressure-sensitive adhesive tape of claim 14 wherein the polyisoprene comprises 30 to 50 percent of the elastomeric component, the block copolymer is a linear block copolymer comprised predominantly of diblock and triblock species, the A block has an average molecular weight between 4,000 and 50,000, and the B block has an average molecular weight between about 5,000 and 500,000.

Claim 21

The pressure-sensitive adhesive tape of claim 14 wherein the elastomeric component comprises 35 to 55 weight percent of the functional adhesive mixtures and the tackifying component comprises 45 to 65 weight percent of the functional adhesive mixture.

Claim 22

The pressure-sensitive adhesive tape of claim 19 wherein 25 to 60 weight percent of the functional adhesive mixture is a solid tackifying resin and 5 to 20 weight percent of the functional adhesive mixture is liquid tackifying resin or plasticizing oil.

Claim 23

The pressure-sensitive adhesive tape of claim 19 wherein the adhesive composite midblock glass transition temperature is from 245 to 255 Kelvin.

Claim 24

The pressure-sensitive adhesive tape of claim 19 wherein 30 to 55 weight percent of the functional adhesive mixture is a solid tackifying resin and 5 to 20 weight percent of the functional adhesive mixture is selected from the group consisting of liquid tackifying resin and plasticizing oil.

Claim 25

The pressure-sensitive adhesive tape of claim 22 wherein the tackifying resin is selected from the group consisting of aliphatic hydrocarbon resins, mixed aliphatic/aromatic tackifying resins, polyterpene tackifiers and hydrogenated tackifying resins, and the block copolymer percent diblock is less than 85 percent.

Claim 26

The pressure-sensitive adhesive tape of claim 23 where the plasticizing oil is selected from the group consisting of naphthionic oil and aromatic oils, and the block copolymer percent diblock is less than 75 percent.

Claim 27

A diaper consisting of an absorbent pad, a liquid-impermeable outer layer attached to one face of said pad, and a liquid-permeable inner layer attached to an opposite face of said pad, a reinforcing layer attached to said outer layer, and a fastening tab having a free end for attachment to said reinforcing layer, an opposite end of said fastening tab permanently attached to said diaper, said free end comprising a backing and an adhesive layer of a functional adhesive mixture of; 30 to 60 weight percent of an elastomeric component consisting essentially of 4 to 55 percent polyisoprene having a number average molecular weight of greater than 100,000 and 96 to 45 percent of an AB(A) block copolymer wherein the A block is 10 to 50 percent of the copolymer and comprises a ring alkylated styrene or styrene and the B block is derived primarily from isoprene, said block copolymer comprising less than 95 weight percent diblock copolymer, and 40 to 70 weight percent of a tackifying component comprising solid tackifying resin, solid tackifying resin with a liquid tackifying resin or plasticizing oil, or solid tackifying resin with liquid tackifying resin and plasticizing oil so as to provide an adhesive mixture having a composite midblock glass transition temperature in the range of 240 to 265 Kelvin.

Claim 28

A diaper consisting of an absorbent pad, a liquid-impermeable outer layer attached to one face of said pad, and a liquid-permeable inner layer attached to an opposite face of said pad, a reinforcing layer attached to said outer layer, and a fastening tab having a free end for attachment to said reinforcing layer, an opposite end of said fastening tab permanently attached to said diaper, said free end comprising a backing and an adhesive layer of a functional adhesive mixture of; 30 to 60 weight percent of an elastomeric component consisting essentially of 4 to 55 percent polyisoprene having a number average molecular weight of greater than 100,000 and 96 to 45 percent of an AB(A) block copolymer wherein the A block is 10 to 50 percent of the copolymer and comprises a ring alkylated styrene or styrene and the B block is derived primarily from isoprene, said block copolymer comprising less than 95 weight percent diblock copolymer, and 40 to 70 weight percent of a tackifying component comprising solid tackifying resin, solid tackifying resin with a liquid tackifying resin or plasticizing oil, or solid tackifying resin with liquid tackifying resin and plasticizing oil so as to provide an adhesive mixture having a composite midblock glass transition temperature in the range of 240 to 265 Kelvin.