Method of magnetically and/or electrostatically positioning pressure-sensitive adhesive beads and magnetically positionable pressure-sensitive

• US 5,599,618 A
• Filed: 11/15/1994
• Issued: 02/04/1997
• Est. Priority Date: 03/09/1993
• Status: Expired due to Fees

• Current Assignee: Minnesota Mining and Manufacturing Co (3M Company)
• Original Assignee: Minnesota Mining and Manufacturing Co (3M Company)
• Inventors: Callahan, Joseph P. Jr., Groess, Michael S., Weigel, Mark D., Enanoza, Rudyard M.
• Primary Examiner(s): Le, Hoa T.
• Application Number:
  US08/339,925
• Time in Patent Office: 812 Days
• Field of Search: 428/323, 428/328, 428/329, 428/403, 428/692, 428/900, 428/913
• US Class Current: 428/323
• CPC Class Codes: C08J 3/12 Powdering or granulating
• CPC Class Codes: C08J 3/124 Treatment for improving the free-flowing characteristics
• CPC Class Codes: C08J 3/128 Polymer particles coated by inorganic and non-macromolecular organic compounds
• CPC Class Codes: C09J 2301/204 the adhesive coating being discontinuous
• CPC Class Codes: C09J 2433/00 Presence of (meth)acrylic polymer
• CPC Class Codes: C09J 7/38 Pressure-sensitive adhesives [PSA]
• CPC Class Codes: G03G 9/093 Encapsulated toner particles
• CPC Class Codes: G03G 9/09342 Inorganic compounds
• CPC Class Codes: G03G 9/09385 Inorganic compounds
• CPC Class Codes: Y10S 428/90 Magnetic feature
• CPC Class Codes: Y10S 428/913 Material designed to be responsive to temperature, light, moisture
• CPC Class Codes: Y10T 428/25 Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles
• CPC Class Codes: Y10T 428/2991 Coated

Abstract

The present invention provides pressure-sensitive adhesive beads that comprise a tacky pressure-sensitive adhesive core and a non-tacky shell material that surrounds the area wherein the beads are capable of being positioned via magnetic means. The present invention also provides method(s) of preparing adhesive coated substrates using pressure-sensitive adhesive bead(s) that are magnetically responsive, electrostatically responsive or both by using magnetic forces, electrostatic forces or both.

Claims

1. A coated substrate comprising a substrate having a layer of pressure-sensitive adhesive which displays pressure-sensitive tack coated thereon, wherein the pressure-sensitive adhesive is formed from free flowing adhesive beads wherein each adhesive bead consists essentially of a pressure-sensitive adhesive core and a tack-free shell therearound, wherein the pressure-sensitive adhesive core consists essentially of a pressure-sensitive adhesive and wherein the bead consists essentially of a magnetically responsive material and wherein the beads are capable of being applied to the substrate via magnetic forces, and wherein upon activation by heat and/or pressure the beads form a layer of pressure-sensitive adhesive that displays pressure-sensitive tack on the substrate.

2. The coated substrate of claim 1 wherein for each adhesive bead the adhesive core consists essentially of a magnetically responsive material, the tack-free shell consists essentially of a magnetically responsive material, or both the adhesive core and the tack-free shell consist essentially of a magnetically responsive material.

3. The coated substrate of claim 1 wherein each adhesive bead consists essentially of a pressure-sensitive adhesive core and a tack-free shell therearound wherein the shell consists essentially of a magnetically responsive material.

4. The coated substrate of claim 1 wherein each adhesive bead consists essentially of a pressure-sensitive adhesive core and a tack-free continuous shell consisting essentially of magnetically responsive material disposed about the core.

5. The coated substrate of claim 1 wherein for each adhesive bead the shell comprises a discontinuous shell.

6. The coated substrate of claim 1 wherein for each adhesive bead the shell comprises a continuous shell.