Adhesive and its use for an at least one-layer PSA sheet strip which can be redetached without residue or destruction by extensive stretching substantially in the bond plane

• US 20040092663A1
• Filed: 07/28/2003
• Published: 05/13/2004
• Est. Priority Date: 11/08/2002
• Status: Active Grant

• Current Assignee: Tesa SE (Maxingvest AG)
• Original Assignee: Tesa AG (Maxingvest AG)
• Inventors: Krawinkel, Thorsten
• Granted Patent: US 7,309,524 B2
• Time in Patent Office: Days
• US Class Current: 525/89
• CPC Class Codes: C08F 297/04 polymerising vinyl aromatic monomers and conjugated dienes
• CPC Class Codes: C08F 8/04 Reduction, e.g. hydrogenation
• CPC Class Codes: C08L 53/02 of vinyl-aromatic monomers and conjugated dienes
• CPC Class Codes: C08L 53/025 modified
• CPC Class Codes: C09J 153/02 Vinyl aromatic monomers and conjugated dienes
• CPC Class Codes: C09J 153/025 modified
• CPC Class Codes: C09J 2301/162 the carrier being a laminate constituted by plastic layers only
• CPC Class Codes: C09J 2301/308 the adhesive tape or sheet losing adhesive strength when being stretched, e.g. stretch adhesive
• CPC Class Codes: C09J 2400/243 in the substrate
• CPC Class Codes: C09J 2453/00 Presence of block copolymer
• CPC Class Codes: Y10T 428/249983 As outermost component
• CPC Class Codes: Y10T 428/28 Web or sheet containing structurally defined element or component and having an adhesive outermost layer
• CPC Class Codes: Y10T 428/2848 Three or more layers
• CPC Class Codes: Y10T 428/2883 including addition polymer of diene monomer [e.g., SBR, SIS, etc.]

Abstract

An adhesive for an at least one-layer pressure sensitive adhesive sheet strip which is residuelessly and nondestructively redetachable by extensive stretching substantially in the bond plane, said adhesive being composed of at least one block copolymer having one or two end blocks composed of vinylaromatics, and a block composed of a conjugated diene, wherein the fraction of 1,2-linked diene is selectively hydrogenated.

Claims

1. An adhesive for an at least one-layer pressure sensitive adhesive sheet strip which is residuelessly and nondestructively redetachable by extensive stretching substantially in the bond plane, said adhesive being comprised of

at least one block copolymer having one or two end blocks composed of vinylaromatics, and

a block composed of a conjugated diene, wherein the fraction of 1,2-linked diene is selectively hydrogenated.

2. An adhesive as claimed in claim 1, containing from 20 to 70% by weight of styrene block copolymer, relative to the total adhesive.

3. An adhesive as claimed in claim 2, containing from 30 to 60% by weight of styrene block copolymer, relative to the total adhesive.

4. An adhesive as claimed in claim 3, containing from 35 to 55% by weight of styrene block copolymer, relative to the total adhesive.

5. An adhesive as claimed in claim 1, wherein the vinylaromatics are partly hydrogenated styrene-isoprene-styrene block copolymers, styrene-butadiene-styrene block copolymers or a mixture of the two.

6. An adhesive as claimed in claim 1, comprising styrene block copolymers which are completely hydrogenated in the elastomer block and are based on styrene-ethylene/butylene-styrene and/or styrene-ethylene/propylene-styrene.

7. An adhesive as claimed in claim 1, wherein the vinyl aromatic block copolymers are maleic anhydride-modified, silane-modified or epoxidized.

8. An adhesive as claimed in claim 1, wherein the block copolymers possess polystyrene endblocks.

9. An adhesive as claimed in claim 1, wherein the block copolymers comprise from 10% by weight to 35% by weight polyvinylaromatics.

10. An adhesive as claimed in claim 9, wherein said block copolymers comprise from 15% by weight to 32% by weight polyvinylaromatics.

11. An adhesive as claimed in claim 1, further comprising tackifier resins.

12. An adhesive as claimed in claim 1, comprising further components selected from the group consisting of plasticizers, aging inhibitors, processing assistants, fillers, dyes, optical brighteners, stabilizers, and endblock reinforcer resins.

13. An at least one-layer pressure sensitive adhesive sheet strip which is residuelessly and nondestructively redetachable by extensive stretching substantially in the bond plane, having the adhesive of claim 1 on at least one side thereof.

14. The pressure sensitive adhesive sheet strip of claim 13, wherein said at least one-layer is two or three layers.

15. The pressure sensitive adhesive sheet strip of claim 13, wherein the adhesive sheet strip includes an intermediate foam carrier.

16. The pressure sensitive adhesive sheet strip of claim 14, wherein the adhesive sheet strip includes an intermediate foam carrier.