Adhesive tape

• US 5,897,949 A
• Filed: 11/24/1997
• Issued: 04/27/1999
• Est. Priority Date: 11/30/1996
• Status: Expired due to Term

• Current Assignee: Tesa SE (Maxingvest AG)
• Original Assignee: Beiersdorf AG (Maxingvest AG)
• Inventors: Junghans, Andreas, Luhmann, Bernd
• Primary Examiner(s): ZIRKER, DANIEL R
• Application Number:
  US08/977,254
• Time in Patent Office: 519 Days
• Field of Search: 428/343, 428/317.3, 428/317.7, 428/355 BL, 428/355 RA
• US Class Current: 428/317.3
• 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 2301/18 characterized by perforations in the adhesive tape
• 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 7/22 Plastics; Metallised plastics
• CPC Class Codes: C09J 7/26 Porous or cellular plastics
• CPC Class Codes: C09J 7/38 Pressure-sensitive adhesives [PSA]
• CPC Class Codes: Y10T 428/249983 As outermost component
• CPC Class Codes: Y10T 428/249985 Composition of adhesive or bonding component specified
• 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 428/2861 having readily strippable combined with readily readhearable properties [e.g., stick-ons, etc.]
• CPC Class Codes: Y10T 428/2883 including addition polymer of diene monomer [e.g., SBR, SIS, etc.]

Abstract

Adhesive tape for a bond which can be redetached by pulling, without residue and without damage, having a foam backing coated on one or both sides with a self-adhesive composition, characterized in that

a) on at least one of the two sides of the foam backing there is applied a self-adhesive composition whose ratio of tear strength to stripping force (peel force) at a peel angle of less than 10° to the bond surface is greater than 1.2:1,

b) the foam backing is subjected to controlled pretreatment/damaging in such a way that the detachment force (stripping force) is lowered relative to an analogous self-adhesive tape with a foam backing which has not been correspondingly pretreated/damaged, and

c) the foam backing does not have a tear strength which is sufficient for redetachment without residue or damage.

Claims

1. Adhesive tape for a bond which can be detached by pulling, without residue and without damage, having a foam backing coated on one or both sides with a self-adhesive composition, comprising

a) a foamed backing having applied thereto on at least one of the two sides of the foam backing a self-adhesive composition whose ratio of tear strength to stripping force (peel force) at a peel angle of less than 10 to the bond surface is greater than 1.2:

1,

b) the foam backing being subjected to controlled pretreatment/damaging by incision in such a way that the mechanical strength of the backing is reduced when the self-adhesive tape subsequently produced using the damaged backing is stretched in the direction of the bond in the course of detaching the tape by pulling, the detachment force (stripping force) is lowered relative to an analogous self-adhesive tape with a foam backing which has not been correspondingly pretreated/damaged,

c) the foam backing not having a tear strength which is sufficient for detachment without residue or damage.

2. Adhesive tape according to claim 1, wherein the foam backing is coated on both sides with self-adhesive composition.

3. Adhesive tape according to claim 1, wherein the self-adhesive composition is based on block copolymers.

4. Adhesive tape according to claim 3, wherein the self-adhesive composition is based on block copolymers of vinylaromatic compounds.

5. Adhesive tape according to claim 1, wherein the self-adhesive composition is based on block copolymers comprising polymer blocks of vinylaromatic compounds (A blocks) and those formed by polymerization of 1,3-dienes (D blocks).

6. Adhesive tape according to claim 1, wherein the self-adhesive composition comprises tackifiers and, optionally further blend components and/or additives.

7. Adhesive tape according to claim 1, wherein the pretreatment/damaging of the foam backing is carried out by means of full cuts, partial cuts, perforation or punching.

8. Adhesive tape according to claim 7, wherein the pretreatment covers the total area of the backing or a limited portion of the backing.

9. Adhesive tape according to claim 7, wherein the pretreatment can be a regular structure or sequence or can be irregular.

10. Adhesive tape according to claim 1, wherein the damage sites penetrate partway or completely through the foam backing.

11. Adhesive tape according to claim 1, wherein the tape is in the form of sections, where one end of a section has a non-tacky grip tab and the other end, optionally, has an adhesive area which decreases towards the end.

12. Adhesive tape according to claim 11, wherein the grip tab is formed by laminated-on film sections whose sides in contact with the self-adhesive composition have been given an anti-adhesive finish.

13. Adhesive tape according to claim 1, wherein the self-adhesive does not penetrate the damaged foam backing such that the mechanical strength of the damaged foam backing is not reduced.

14. Method for detaching a bonded section of an adhesive tape according to claim 1, without residue and without damage, comprising pulling one end of the section in the bond plane until the bond is detached.

15. Method according to claim 14, wherein the section is coated on both sides with self-adhesive composition and is used together with a hook, a base plate or an article which is to be suspended, and, optional, is preassembled on such articles.

17. Adhesive tape according to claim 1, wherein the foam backing is coated prior to pretreatment/damaging, the damaging including removing material from the self-adhesive coated foam backing, such that the self-adhesive does not penetrate the damaged foam backing such that the mechanical strength of the damaged foam backing is not reduced.

16. Adhesive tape for a bond which can be detached by pulling, without residue and without damage, having a foam backing coated on one or both sides with a self-adhesive compositions, comprising

a) a foamed backing having applied thereto on at least one of the two sides of the foam backing a self-adhesive composition whose ratio of tear strength to stripping force (peel force) at a peel angle of less than 10 degrees to the bond surface is greater than 1.2:

1,

b) the foam backing being subjected to controlled pretreatment/damaging by means of incisions, full cuts, partial cuts, perforation or punching in such a way that the mechanical strength of the foam backing is reduced when the self-adhesive tape subsequently produced using the damaged backing is stretched in the direction of the bond in the course of detaching the tape by pulling, the detachment force (stripping force) being lowered relative to an analogous self-adhesive tape with a foam backing which has not been correspondingly pretreated/damaged,

c) the foam backing not having a tear strength which is sufficient for detachment without residue or damage.