Detachable adhesive compounds

• US 6,855,760 B1
• Filed: 05/17/2000
• Issued: 02/15/2005
• Est. Priority Date: 05/26/1999
• Status: Expired due to Term

• Current Assignee: Henkel Corporation (Henkel AG & Co KGaA)
• Original Assignee: Henkel KGaA (Henkel AG & Co KGaA)
• Inventors: Schirra, Herrmann, Christophliemk, Peter, Kirsten, Christian N., Nonninger, Ralph, Schmidt, Helmut
• Primary Examiner(s): Yoon, Tae H.
• Application Number:
  US09/979,956
• Time in Patent Office: 1,735 Days
• Field of Search: 524/394, 524/401, 524/423, 524/431, 524/440, 524/441, 528/503, 522/71, 252/62.51 R, 252/62.56, 252/62.9 R, 428/689
• US Class Current: 524/394
• CPC Class Codes: C09J 11/04 inorganic
• CPC Class Codes: C09J 2301/502 process for debonding adherents
• CPC Class Codes: C09J 5/00 Adhesive processes in general; Adhesive processes not provided for elsewhere, e.g. relating to primers
• CPC Class Codes: C09J 9/02 Electrically-conducting adhesives
• CPC Class Codes: Y10S 977/837 Piezoelectric property of nanomaterial
• CPC Class Codes: Y10S 977/838 Magnetic property of nanomaterial

Abstract

This invention relates to adhesive compositions of which the binder system contains nanoscale particles with ferromagnetic, ferrimagnetic, superparamagnetic or piezoelectric properties. The invention also relates to dissolvable adhesive bonds and to a process for dissolving adhesive bonds.

Claims

1. An adhesive composition, comprising a binder system and nanoscale particles having piezoelectric properties, wherein the nanoscale particles comprise one or more piezoelectric materials selected from the group consisting of quartz, tourmaline, barium titanate, lithium sulfate, potassium tartrate, sodium tartrate, potassium sodium tartrate, and ethylenediamine tartrate.

2. The composition of claim 1, wherein the nanoscale particles have a mean particle size of 100 nm or less.

3. The composition of claim 2, wherein the nanoscale particles have a mean particle size of 50 nm or less.

4. The composition of claim 3, wherein the nanoscale particles have a mean particle size of 30 nm or less.

5. The adhesive composition of claim 1, comprising 1% to 30% by weight of the nanoscale particles.

6. The adhesive composition of claim 5, comprising 3% to 20% by weight of the nanoscale, particles.

7. An article of manufacture, comprising two or more substrates adhesively bonded by a dissolvable layer of adhesive matrix, said matrix comprising the adhesive composition of claim 1.

8. A process for separating two or more substrates adhesively bonded by a thermoplastic adhesive matrix that comprises a thermoplastic binder and nanoscale particles having ferromagnetic, ferrimagnetic, superparamagnetic, or piezoelectric properties, said process comprising the steps of exposing the thermoplastic adhesive matrix to one or more of an electrical, magnetic, or electromagnetic alternating field whereby the matrix is heated beyond the softening point of the thermoplastic binder, and optionally separating the substrates with mechanical force.

10. The process of claim 8, wherein the nanoscale particles comprise one or more ferrimagnetic, ferromagnetic, or superparamagnetic materials selected from the group consisting of aluminium, cobalt, iron, nickel, nickel alloys, n-maghemite (γ

—

Fe₂O₃) metal oxides, n-magnetite (Fe₃O₄) metal oxides, and MeFe₂O₄ ferrites, wherein Me stands for a divalent metal selected from the group consisting of manganese, copper, zinc, cobalt, nickel, magnesium, calcium, and cadmium.

9. A process for separating two or more substrates adhesively bonded by a thermoset adhesive matrix that comprises a crosslinked binder and nanoscale particles having ferromagnetic, ferrimagnetic, superparamagnetic, or piezoelectric properties, said process comprising the steps of exposing the thermoset adhesive matrix to one or more of an electrical, magnetic, or electromagnetic alternating field whereby the adhesive matrix is heated to a temperature that at least partly splits the crosslinked structure of the binder, and optionally separating the substrates with mechanical force.