Planarization treatment of pressure sensitive adhesive for rigid-to-rigid substrate lamination

• US 8,603,288 B2
• Filed: 01/18/2008
• Issued: 12/10/2013
• Est. Priority Date: 01/18/2008
• Status: Active Grant

• Current Assignee: Rockwell Collins, Inc. (Rtx Corporation)
• Original Assignee: Rockwell Collins, Inc. (Rtx Corporation)
• Inventors: Sampica, James D., Nemeth, Paul R., Barnidge, Tracy J., Marzen, Vincent P.
• Primary Examiner(s): SCHATZ, CHRISTOPHER T
• Application Number:
  US12/009,472
• Publication Number:
  US 20090186218A1
• Time in Patent Office: 2,153 Days
• Field of Search: 156/285, 156/286, 156/381, 156/382, 156/583.3, 349/187, 269/287, 269/288, 10026901-26904, 425/389
• US Class Current: 156/285
• CPC Class Codes: B29C 2043/3233 exerting pressure on mould parts
• CPC Class Codes: B29C 2043/3647 Membranes, diaphragms
• CPC Class Codes: B29C 2043/3649 Inflatable bladders using gas or fluid and related details
• CPC Class Codes: B29C 33/20 Opening, closing or clamping
• CPC Class Codes: B29C 43/12 using bags surrounding the moulding material or using membranes contacting the moulding material
• CPC Class Codes: B29C 43/203 Making multilayered articles
• CPC Class Codes: B29C 43/3642 Bags, bleeder sheets or cauls for isostatic pressing
• CPC Class Codes: B29C 53/18 of plates or sheets
• CPC Class Codes: B29D 7/01 Films or sheets
• CPC Class Codes: B32B 15/08 of synthetic resin
• CPC Class Codes: B32B 2250/05 5 or more layers
• CPC Class Codes: B32B 2250/40 Symmetrical or sandwich layers, e.g. ABA, ABCBA, ABCCBA
• CPC Class Codes: B32B 2255/10 on synthetic resin layer or on natural or synthetic rubber layer
• CPC Class Codes: B32B 2255/26 Polymeric coating
• CPC Class Codes: B32B 2457/00 Electrical equipment
• CPC Class Codes: B32B 2457/08 PCBs, i.e. printed circuit boards
• CPC Class Codes: B32B 2457/202 LCD, i.e. liquid crystal displays
• CPC Class Codes: B32B 2457/206 Organic displays, e.g. OLED
• CPC Class Codes: B32B 2457/208 Touch screens
• CPC Class Codes: B32B 25/08 of synthetic resin
• CPC Class Codes: B32B 27/08 : of synthetic resin
• CPC Class Codes: B32B 27/32 : comprising polyolefins comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30
• CPC Class Codes: B32B 7/12 : using interposed adhesives or interposed materials with bonding properties
• CPC Class Codes: Y10T 428/28 : Web or sheet containing structurally defined element or component and having an adhesive outermost layer

Abstract

The present invention is a process for performing a planarization treatment of pressure-sensitive adhesive (PSA). The process includes positioning a first substrate onto a support surface of a planarization tool. The process further includes placing at least one layer of PSA onto the first substrate. The process further includes positioning a second substrate onto the layer(s) of PSA. The process further includes applying a pressure to the second substrate via a flexible membrane, said pressure being applied in a generally uniform, unidirectional and localized manner. Further, the applied pressure flattens the PSA between the first substrate and the second substrate for promoting suitability of the PSA for use in rigid-to-rigid lamination processes.

Claims

1. A process for performing a planarization treatment of pressure-sensitive adhesive (PSA), comprising:

positioning a first substrate onto a support surface of a planarization tool;

placing at least one layer of PSA onto the first substrate;

positioning a second substrate onto the layer(s) of PSA;

selecting a predetermined duration of time based on a desired level of flatness for a flattened PSA;

applying a pressure to the second substrate via a flexible membrane for the predetermined duration of time to form the flattened PSA, said pressure being applied in a generally uniform, unidirectional and localized manner, wherein the applied pressure flattens the PSA between the first substrate and the second substrate to form the flattened PSA;

removing the flattened PSA from the planarization tool and the second substrate; and

removing the second substrate from the planarization tool; and

adhering the flattened PSA to a display component in a subsequent rigid-to-rigid lamination process after removal of the flattened PSA from the planarization tool and the second substrate.

2. A process as claimed in claim 1, further comprising:

prior to applying the pressure, positioning a first plastic film layer between the first substrate and the at least one layer of PSA; and

placing a second plastic film layer between the second substrate and the at least one layer of PSA.

3. A process as claimed in claim 1, further comprising:

placing a carriage of the planarization tool onto the support surface prior to applying the pressure, the carriage configured for allowing the applied pressure to be applied to the second substrate in a generally uniform, unidirectional and localized manner.

4. A process as claimed in claim 3, further comprising:

prior to applying the pressure, placing the flexible membrane onto the carriage, the flexible membrane configured for forming a sealed cavity with the planarization tool, said sealed cavity containing the first substrate, the at least one layer of PSA, the second substrate, the first plastic film layer and the second plastic film layer.

5. A process as claimed in claim 2, further comprising:

prior to applying the pressure, connecting the planarization tool to a vacuum pump to create a vacuum within the sealed cavity, thereby applying a vacuum to the first substrate, the at least one layer of PSA, the second substrate, the first plastic film layer and the second plastic film layer.

6. A process as claimed in claim 5, wherein the vacuum and the pressure are concurrently applied to the first substrate, the at least one layer of PSA, the second substrate, the first plastic film layer and the second plastic film layer.

7. A process as claimed in claim 6, wherein the process is performed at ambient temperature.

8. A process for performing a planarization treatment of pressure-sensitive adhesive (PSA), comprising:

positioning a first substrate onto a support surface of a planarization tool, such that a first surface of the first substrate is in contact with the support surface and a second surface of the first substrate, generally opposite the first surface, is oriented away from the support surface, at least one layer of PSA being pre-adhered to the first substrate;

positioning a second substrate onto the layer(s) of PSA;

selecting a predetermined duration of time based on a desired level of flatness for a flattened PSA;

applying a pressure to the second substrate via a flexible membrane for the predetermined duration of time to form the flattened PSA, said pressure being applied in a generally uniform, unidirectional and localized manner, and

removing the flattened PSA from the planarization tool and the second substrate;

removing the second substrate from the planarization tool;

adhering the flattened PSA to a display component in a subsequent rigid-to-rigid lamination process after removal of the flattened PSA from the planarization tool and the second substrate.

9. A process as claimed in claim 8, wherein the first substrate is at least one of cover glass for a Liquid Crystal Display (LCD) or a touch screen.