Adhesive precursor composition and heat-expandable temporary adhesive therefrom

Patent metadata

Field	Value
Publication number	US-2024182764-A1
Application number	US-202218284189-A
Country	US
Kind code	A1
Filing date	Mar 28, 2022
Priority date	Mar 30, 2021
Publication date	Jun 6, 2024
Grant date	—

Abstract

The present disclosure provides an adhesive precursor composition, comprising a polyfunctional acrylate oligomer, a reactive diluent including an acrylate monomer; a photoinitiator, and heat-expandable microspheres which are capable of expanding above an expansion initiation temperature, Ti, wherein the adhesive precursor composition is a liquid at temperature, Ta, wherein Ta is less than Ti, and the reaction product of the adhesive precursor composition is a heat-expandable temporary adhesive having a maximum value of tan δ at a temperature, Ttan δ max, wherein Ttan δ max is less than Ti. In another aspect, the present disclosure provides a heat-expandable temporary adhesive including the reaction product of an adhesive precursor composition according to any one of the adhesive precursor compositions of the present disclosure.

First claim

What is claimed:

1 . An adhesive precursor composition, comprising:
a polyfunctional acrylate oligomer, a reactive diluent including an acrylate monomer; a photoinitiator; and heat-expandable microspheres which are capable of expanding above an expansion initiation temperature, T i , wherein the adhesive precursor composition is a liquid at temperature, T a , wherein T a is less than T i , and the reaction product of the adhesive precursor composition is a heat-expandable temporary adhesive having a maximum value of tan δ at a temperature, T tan δ max , wherein T tan δ max is less than T i .

2 . The adhesive precursor composition of claim 1 , wherein T tan δ max is at least 10° C. less than T i .

3 . The adhesive precursor composition of claim 1 , wherein T a is at least 10° C. greater than a melting point of the adhesive precursor composition.

4 . The adhesive precursor composition of claim 1 , wherein the polyfunctional acrylate oligomer is selected from at least one of a polyester acrylate oligomer and a urethane acrylate oligomer.

5 . A heat-expandable temporary adhesive comprising the reaction product of an adhesive precursor composition according to claim 1 .

6 . An article comprising:
a first substrate; a second substrate; and a heat-expandable temporary adhesive disposed therebetween, wherein the heat-expandable temporary adhesive is the reaction product of an adhesive precursor composition according to claim 1 .

7 . A method of temporarily bonding two substrates, comprising:
providing a first and second substrate; applying an adhesive precursor composition according to claim 1 onto a surface of the first substrate; contacting a surface of the second substrate to the exposed surface of the adhesive precursor composition; and subjecting the adhesive precursor composition to actinic radiation to cure the adhesive precursor composition, thereby forming a heat-expandable temporary adhesive that temporarily bonds the first and second substrates together.

8 . The method of claim 7 , further comprising heating the heat-expandable temporary adhesive to a temperature, T, greater than T i , thereby expanding the heat-expandable microspheres, causing the heat-expandable temporary adhesive to expand, forming an expanded adhesive which facilitates debonding of at least one of the first and second substrates from the expanded adhesive.

9 . The method of claim 8 , wherein temperature, T, is between 130° C. to 250° C.

10 . The method of claim 7 , wherein facilitating debonding of at least one of the first and second substrates from the expanded adhesive includes at least one of (i) decreasing the adhesion between at least one of the first substrate and the expanded adhesive and the second substrate and the expanded adhesive, (ii) detaching at least one of the first substrate from the expanded adhesive and the second substrate from the expanded adhesive, (iii) causing cohesive failure in the adhesive, and (iv) peeling the temporary adhesive from one of the first and second substrates without damaging the at least one of the first and second substrates.

Assignees

• 3M Innovative Properties Company

Inventors

• Noda Kazuki

Classifications

• C09J2301/416

  use of irradiation · CPC title

• C09J2301/412

  presence of microspheres · CPC title

• C09J133/00 Primary

  Adhesives based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Adhesives based on derivatives of such polymers · CPC title

• B32B7/12

  using interposed adhesives or interposed materials with bonding properties · CPC title

• B32B37/12

  characterised by using adhesives · CPC title