Adhesive film strip

• US 6,284,378 B1
• Filed: 07/01/1997
• Issued: 09/04/2001
• Est. Priority Date: 07/04/1996
• Status: Expired due to Term

• Current Assignee: Tesa SE (Maxingvest AG)
• Original Assignee: Beiersdorf AG (Maxingvest AG)
• Inventors: Lühmann, Bernd, Junghans, Andreas
• Primary Examiner(s): Ahmad, Nasser
• Application Number:
  US08/886,306
• Time in Patent Office: 1,526 Days
• Field of Search: 428/40.1, 428/41.7, 428/41.8, 428/41.9, 428/194, 428/192, 428/214, 428/323, 428/346, 428/347, 428/355, 428/354, 428/349, 206/411, 156/292
• US Class Current: 428/421
• CPC Class Codes: C08L 53/00 Compositions of block copolymers containing at least one sequence of a polymer obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers
• CPC Class Codes: C09J 153/025 modified
• 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 2453/00 Presence of block copolymer
• CPC Class Codes: C09J 2453/006 in the substrate
• CPC Class Codes: C09J 7/22 Plastics; Metallised plastics
• CPC Class Codes: C09J 7/38 Pressure-sensitive adhesives [PSA]
• CPC Class Codes: Y10T 428/14 Layer or component removable to expose adhesive
• CPC Class Codes: Y10T 428/1471 Protective layer
• CPC Class Codes: Y10T 428/1476 Release layer
• CPC Class Codes: Y10T 428/1481 Dissimilar adhesives
• CPC Class Codes: Y10T 428/24777 Edge feature
• CPC Class Codes: Y10T 428/24793 Comprising discontinuous or differential impregnation or bond
• CPC Class Codes: Y10T 428/3154 Of fluorinated addition polymer from unsaturated monomers

Abstract

Adhesive film strip for a temporary bond which can be detached without residue and without damage by pulling in the direction of the bond plane, having a layer structure comprising an elastic backing layer which is provided on one or both sides with an adhesive layer, characterized in that both the backing layer and the adhesive layer(s) comprise styrene block copolymers as base polymers, blended with tackifier resins which are compatible with the elastomer block of the styrene block copolymers used.

Claims

1. An adhesive film strip for a temporary bond which can be detached without residue and without damage by pulling in the direction of the bond plane, said adhesive film strip having a multi-layer structure comprising an elastic backing layer which is provided on both sides with an adhesive layer, wherein both the backing layer and the adhesive layer(s) are composed of chemical compositions comprising styrene block copolymers as base polymers, which styrene block copolymers are blended with tackifier resins which are compatible with an elastomer block of the styrene block copolymers used, but wherein the chemical composition of the backing layer is different from the chemical composition of the adhesive layers.

2. Adhesive film strip according to claim 1, wherein the backing layer and the adhesive layers comprise the same tackifier resins or plasticizer oils.

3. Adhesive film strip according to claim 1, wherein the proportions of the styrene block copolymers in the backing layer and in the adhesive layers are 15-75% by weight.

4. Adhesive film strip according to claim 3, wherein the proportions of the styrene block copolymers in the backing layer and in the adhesive layers are 30-60% by weight or the proportions of the tackifier resins in these layers are 30-65% by weight.

5. Adhesive film strip according to claim 3, wherein the proportions of the styrene block copolymers in the backing layer and in the adhesive layers are 35-55% by weight or the proportions of the tackifier resins in these layers are 35-60% by weight.

6. Adhesive film strip according to claim 1, wherein the tackifier resins are rosin or derivatives thereof or aliphatic or aromatic-modified aliphatic tackifier resin.

7. Adhesive film strip according to claim 6, wherein the tackifier resins are selected from the group consisting of esters of partially hydrogenated rosin having softening points of from +70 to 125°

C. or, for heat-activatable systems, from the group consisting of rosin derivatives having softening points of up to +160°

C.

8. Adhesive film strip according to claim 1, wherein further comprising additional blend components present in the backing layer and in the adhesive layers, said additional blend components being selected from the group consisting of plasticizers, liquid resins, fillers and antiageing agents.

9. Adhesive film strip according to claim 8, wherein the proportions of the additional blend components in the backing layer and in the adhesive layers are up to 40% by weight.

10. Adhesive film strip according to claim 8, wherein the backing layer and the adhesive layers comprise the same migratable blend components.

11. Adhesive film strip according to claim 1, which comprises at one of its ends a grip tab for pulling the direction of the bond plane.

12. Adhesive film strip according to claim 1, wherein its adhesive layers are protected by cover paper or cover film.

13. Adhesive film strip according to claim 1, wherein at least one diffusion barrier layer is provided between said backing layer and at least one of said adhesive layers.

14. Adhesive film strip according to claim 1, wherein the concentration of the tackifier resin in the backing layer and in the adhesive layers is such that any change in said concentration is less than 25% during a period of use of said adhesive film strip.

15. Adhesive film strip according to claim 14, wherein the concentration of the tackifier resin in the backing layer and in the adhesive layers is such that any change in said concentration is less than 15% during a period of use of said adhesive film strip.

16. Adhesive film strip according to claim 14, wherein the concentration of the tackifier resin in the backing layer and in the adhesive layers is such that any change in said concentration is less than 7.5% during a period of use of said adhesive film strip.

33. A method of bonding two materials together for a temporary period of time, wherein once detached, there is no residue, wherein said method comprises binding the two materials with an adhesive film strip according to any one of claims 1-32, and detaching said materials by pulling the strip in the direction of the bond plane.

34. A process for preparing an adhesive film strip according to any one of claims 1-32, comprising:

a) preparing the backing layer and the adhesive layer(s) as individual primary films; and

b) laminating together the individual primary films formed in a) to achieve said multi-layer structure.

17. An adhesive film strip for a temporary bond which can be detached without residue and without damage by pulling in the direction of the bond plane, said adhesive film strip having a multi-layer structure comprising an elastic backing layer which is provided on one or both sides with an adhesive layer, and a diffusion barrier between said backing layer and at least one of said adhesive layer(s), wherein both the backing layer and the adhesive layer(s) are composed of chemical compositions comprising styrene block copolymers as base polymers, which styrene block copolymers are blended with tackifier resins which are compatible with an elastomer block of the styrene block copolymers used, but wherein the chemical composition of the backing layer is different from the chemical composition of the adhesive layer(s).

18. Adhesive film strip according to claim 17, wherein the backing layer and the adhesive layer(s) comprise the same tackifier resins or plasticizer oils.

19. Adhesive film strip according to claim 17, wherein the proportions of the styrene block copolymers in the backing layer and in the adhesive layer(s) are 15-75% by weight.

20. Adhesive film strip according to claim 19, wherein the proportions of the styrene block copolymers in the backing layer and in the adhesive layers are 30-60% by weight or the proportions of the tackifier resins in these layers are 30-65% by weight.

21. Adhesive film strip according to claim 19, wherein the proportions of the styrene block copolymers in the backing layer and in the adhesive layers are 35-55% by weight or the proportions of the tackifier resins in these layers are 35-60% by weight.

22. Adhesive film strip according to claim 17, wherein the tackifier resins are rosin or derivatives thereof or aliphatic or aromatic-modified aliphatic tackifier resin.

23. Adhesive film strip according to claim 22, wherein the tackifier resins are selected from the group consisting of esters of partially hydrogenated rosin having softening points of from +70 to 125°

C. or, for heat-activatable systems, from the group consisting of rosin derivatives having softening points of up to +160°

C.

24. Adhesive film strip according to claim 17, wherein further comprising additional blend components present in the backing layer and in the adhesive layer(s), said additional blend components being selected from the group consisting of plasticizers, liquid resins, fillers and antiageing agents.

25. Adhesive film strip according to claim 24, wherein the proportions of the additional blend components in the backing layer and in the adhesive layer(s) are up to 40% by weight.

26. Adhesive film strip according to claim 24, wherein the backing layer and the adhesive layer(s) comprise the same migratable blend components.

27. Adhesive film strip according to claim 17, wherein the backing layer is provided on both sides with an adhesive layer.

28. Adhesive film strip according to claim 17, which comprises at one of its ends a grip tab for pulling the direction of the bond plane.

29. Adhesive film strip according to claim 17, wherein its adhesive layer(s) is (are) protected by cover paper or cover film.

30. Adhesive film strip according to claim 17, wherein the concentration of the tackifier resin in the backing layer and in the adhesive layer(s) is such that any change in said concentration is less than 25% during a period of use of said adhesive film strip.

31. Adhesive film strip according to claim 30, wherein the concentration of the tackifier resin in the backing layer and in the adhesive layer(s) is such that any change in said concentration is less than 15% during a period of use of said adhesive film strip.

32. Adhesive film strip according to claim 30, wherein the concentration of the tackifier resin in the backing layer and in the adhesive layer(s) is such that any change in said concentration is less than 7.5% during a period of use of said adhesive film strip.