Storage-stable, reactive, pressure-sensitive adhesive tape

Patent metadata

Field	Value
Publication number	US-11926769-B2
Application number	US-202117362006-A
Country	US
Kind code	B2
Filing date	Jun 29, 2021
Priority date	Jun 29, 2020
Publication date	Mar 12, 2024
Grant date	Mar 12, 2024

Abstract

A reactive PSA film that includes: (a) a polymeric film former matrix; (b) one or more reactive components; and (c) a reagent selected from an initiator, a curing agent and an activator. The component (b) is present at a mass fraction of ≥30%, as based on the sum of (a), (b) and (c). Further, ≥50 wt % of the film former matrix is a crystallizable polymer which: (i) exhibits a crystallization enthalpy of <1 J/g in a DSC measurement on cooling at 10K/min from at least 30K above a peak temperature of the melting peak of the polymer or ≥100° C., whichever is greater; and (ii) exhibits a crystallite fusion enthalpy of ≥15 mJ/mg in its pure state in a first heating curve of a DSC measurement at 10K/min and after storage for ≥one month from 15 to 25° C. and relative humidity from 30 to 70%.

First claim

What is claimed is:

1. A reactive pressure-sensitive adhesive film, comprising:
(a) a polymeric film former matrix;
(b) one or more reactive components; and
(c) a reagent selected from an initiator, a curing agent and an activator,
wherein the (b) one or more reactive components is present at a mass fraction of at least 30%, as based on the sum of (a), (b) and (c), and
further wherein at least 50 wt % of the polymeric film former matrix is a crystallizable polymer which:
(i) exhibits a crystallization enthalpy of less than 1 J/g in a differential scanning calorimetry (DSC) measurement, as measured on cooling at a rate of 10 K/min from a starting temperature which is at least 30 K above a peak temperature of the melting peak of the crystallizable polymer or at least 100° C., whichever starting temperature is greater; and
(ii) exhibits a crystallite fusion enthalpy of at least 15 mJ/mg in its pure state, as measured in a first heating curve of a DSC measurement at a heating rate of 10 K/min and after storage for at least one month in a temperature range from 15 to 25° C. and at a relative humidity in the range from 30 to 70%.

2. The adhesive film according to claim 1 , wherein the initiator is a radical initiator.

3. The adhesive film according to claim 1 , wherein the crystallizable polymer further exhibits a crystallization enthalpy of less than 35 J/g in a DSC measurement at a heating rate of 10 K/min from a starting temperature of −140° C.

4. The adhesive film according to claim 3 , wherein the crystallization enthalpy is less than 10 J/g in the DSC measurement at a heating rate of 10 K/min from a starting temperature of −140° C.

5. The adhesive film according to claim 1 , wherein the peak temperature of the melting peak of the crystallizable polymer is from 30° C. to 150° C.

6. The adhesive film according to claim 1 , wherein the (b) one or more reactive components is present in a mass fraction of at least 35 wt %, as based on the sum of (a), (b) and (c).

7. The adhesive film according to claim 1 , wherein the (b) one or more reactive components is present in a mass fraction of less than 70 wt %, as based on the sum of (a), (b) and (c).

8. The adhesive film according to claim 1 , wherein the crystallizable polymer exhibits a crystallite fusion enthalpy of not more than 50 mJ/mg in its pure state, as measured in a first heating curve of a DSC measurement at a heating rate of 10 K/min and after storage for at least one month in a temperature range from 15 to 25° C. and at a relative humidity in the range from 30 to 70%.

9. The adhesive film according to claim 1 , wherein the film is further configured such that a curing reaction of the film can be initiated in a temperature range from 15° C. to 30° C.

10. A reactive pressure-sensitive adhesive film, comprising:
(a) a polymeric film former matrix;
(b) one or more reactive components; and
(c) a reagent selected from an initiator, a curing agent and an activator,
wherein the (b) one or more reactive components is present at a mass fraction of at least 30%, as based on the sum of (a), (b) and (c), and
further wherein at least 50 wt % of the polymeric film former matrix is a crystallizable polymer that is a polyurethane which:
(i) exhibits a crystallization enthalpy of less than 1 J/g in a differential scanning calorimetry (DSC) measurement, as measured on cooling at a rate of 10 K/min from a starting temperature which is at least 30 K above a peak temperature of the melting peak of the crystallizable polymer or at least 100° C., whichever starting temperature is greater; and
(ii) exhibits a crystallite fusion enthalpy of at least 15 mJ/mg in its pure state, as measured in a first heating curve of a DSC measurement at a heating rate of 10 K/min and after storage for at least one month in a temperature range from 15 to 25° C. and at a relative humidity in the range from 30 to 70%.

11. The adhesive film according to claim 10 , wherein the polyurethane comprises units derived from polyester diols.

12. The adhesive film according to claim 10 , wherein the (b) one or more reactive components comprise one or more of epoxide, hydroxyl, acrylate, methacrylate and isocyanate groups.

13. The adhesive film according to claim 10 , wherein the initiator is a radical initiator.

14. The adhesive film according to claim 10 , wherein the crystallizable polymer further exhibits a crystallization enthalpy of less than 35 J/g in a DSC measurement at a heating rate of 10 K/min from a starting temperature of −140° C.

15. The adhesive film according to claim 14 , wherein the crystallization enthalpy is less than 10 J/g in the DSC measurement at a heating rate of 10 K/min from a starting temperature of −140° C.

16. The adhesive film according to claim 10 , wherein the peak temperature of the melting peak of the crystallizable polymer is from 30° C. to 150° C.

17. The adhesive film according to claim 10 , wherein the (b) one or more reactive components is present in a mass fraction of at least 35 wt %, as based on the sum of (a), (b) and (c).

18. The adhesive film according to claim 10 , wherein the (b) one or more reactive components is present in a mass fraction of less than 70 wt %, as based on the sum of (a), (b) and (c).

19. The adhesive film according to claim 10 , wherein the crystallizable polymer exhibits a crystallite fusion enthalpy of not more than 50 mJ/mg in its pure state, as measured in a first heating curve of a DSC measurement at a heating rate of 10 K/min and after storage for at least one month in a temperature range from 15 to 25° C. and at a relative humidity in the range from 30 to 70%.

20. An adhesive film system, comprising:
at least two reactive pressure-sensitive adhesive films according to claim 1 and in contact with one another,
wherein the first pressure-sensitive adhesive film according to claim 1 is further configured such that the reagent is a radical initiator, and
further wherein the second pressure-sensitive adhesive film according to claim 1 is further configured such that the reagent is an activator or an accelerator.

Assignees

• Tesa Se

Inventors

• KEITE-TELGENBüSCHER KLAUS
• Hannemann Frank
• Moehrke Claudia
• Kramp Stefan

Classifications

• C09J7/38 Primary

  Pressure-sensitive adhesives [PSA] · CPC title

• C08K5/0025

  Crosslinking or vulcanising agents; including accelerators · CPC title

• C08K5/10

  Esters; Ether-esters · CPC title

• C08K5/14

  Peroxides · CPC title

• C08K5/1515

  Three-membered rings · CPC title