Method of manufacturing composite sheet materials

• US 5,591,496 A
• Filed: 07/13/1993
• Issued: 01/07/1997
• Est. Priority Date: 11/20/1990
• Status: Expired due to Term

• Current Assignee: Linpac Plastics International Limited
• Original Assignee: Linpac Plastics International Limited
• Inventors: Anderson, Michael C., Heap, Anthony J., Grone, Horst-Ditmar
• Primary Examiner(s): CHEN, VIVIAN
• Application Number:
  US08/050,467
• Time in Patent Office: 1,274 Days
• Field of Search: 428/36.5, 428/903.3, 428/304.4, 156/244.11, 264/DIG. 10, 264/45.6
• US Class Current: 428/36.5
• CPC Class Codes: B29C 2793/0063 Cutting longitudinally
• CPC Class Codes: B29C 35/045 using gas or flames
• CPC Class Codes: B29C 48/0014 producing flat articles having components brought in contact outside the extrusion die
• CPC Class Codes: B29C 48/0018 combined with shaping by orienting, stretching or shrinking, e.g. film blowing B29C48/0017 takes precedence
• CPC Class Codes: B29C 48/0019 combined with shaping by flattening, folding or bending
• CPC Class Codes: B29C 48/002 combined with surface shaping
• CPC Class Codes: B29C 48/0021 combined with joining, lining or laminating
• CPC Class Codes: B29C 48/0022 combined with cutting
• CPC Class Codes: B29C 48/10 flexible, e.g. blown foils
• CPC Class Codes: B29C 48/21 the layers being joined at their surfaces
• CPC Class Codes: B29C 65/10 using hot gases (e.g. combustion gases) or flames coming in contact with at least one of the parts to be joined
• CPC Class Codes: B29K 2105/26 Scrap or recycled material
• CPC Class Codes: B32B 2272/00 Resin or rubber layer comprising scrap, waste or recycling material
• CPC Class Codes: B32B 27/32 comprising polyolefins comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30
• CPC Class Codes: B32B 37/153 at least one layer is extruded and immediately laminated while in semi-molten state
• CPC Class Codes: B32B 38/0036 Heat treatment for heating or cooling of layers during lamination B32B37/06, B32B37/08
• CPC Class Codes: B32B 38/18 Handling of layers or the laminate
• CPC Class Codes: Y10S 264/10 Foamed polystyrene mold filling
• CPC Class Codes: Y10T 428/1376 Foam or porous material containing
• CPC Class Codes: Y10T 428/249953 Composite having voids in a component [e.g., porous, cellular, etc.]

Abstract

A method of making a composite sheet material in which at least one lamina of previously unused expanded polystyrene is bonded to a second lamina of recycled expanded polystyrene. The laminae are continuously formed from separate extruders and are merged promptly after extrusion. Heat is applied to the laminae just before they are merged.

Claims

1. A method of making a composite sheet material, comprising the steps of forming a first lamina of previously unused expanded polystyrene from a first extruder, simultaneously forming a second lamina of recycled expanded polystyrene from a second extruder, and promptly bonding the freshly extruded laminae to each other.

2. A method according to claim 1, including the step of applying heat to at least one of the laminae across the full width thereof immediately before the bonding is carried out.

3. A method according to claim 1, including the step of applying heat to both of the laminae across the full widths thereof immediately before the bonding is carried out.

11. A composite sheet material made by a method according to claim 1, comprising a first lamina of previously unused expanded polystyrene, and a second lamina of recycled expanded polystyrene bonded to the first lamina.

4. A method of making a composite sheet material, comprising the steps of forming a pair of cover laminae of previously unused expanded polystyrene from a first extruder, simultaneously forming at least one other lamina of recycled expanded polystyrene from a second extruder, promptly enclosing the freshly extruded recycled lamina between the freshly extruded cover laminae, and immediately bonding the cover laminae to the recycled lamina.

5. A method according to claim 4, including the step of applying heat to the recycled lamina across the full width thereof immediately before enclosing the recycled lamina between the cover laminae.

6. A method according to claim 5, including the step of applying heat to the cover laminae across the full widths thereof immediately before enclosing the recycled lamina between the cover laminae.

7. A method according to claim 5, including the step of applying heat to the cover laminae and the recycled lamina across the full widths thereof immediately before enclosing the recycled lamina between the cover laminae.

12. A composite sheet material made by a method according to claim 4, comprising a pair of cover laminae of previously unused expanded polystyrene, and at least one other lamina of recycled expanded polystyrene, the recycled lamina being enclosed between and bonded to the cover laminae.

8. A method of making a composite sheet material, comprising the steps of extruding a pair of cover laminae of previously unused expanded polystyrene, providing at least one other lamina of recycled expanded polystyrene, applying heat to the recycled lamina across the full width thereof, promptly enclosing the heated recycled lamina between the freshly extruded cover laminae, and immediately bonding the cover laminae to the recycled lamina.

9. A method according to claim 8, including the step of applying heat to the cover laminae across the full widths thereof simultaneously with the said application of heat to the recycled lamina.

13. A composite sheet material made by a method according to claim 8, comprising a pair of cover laminae of previously unused expanded polystyrene, and at least one other lamina of recycled expanded polystyrene, the recycled lamina being enclosed between and bonded to the cover laminae.

10. A method of making a composite sheet material, comprising the steps of extruding a pair of cover laminae of expanded polystyrene, providing at least one other lamina of material having interstices formed therein, applying heat to the cover laminae across the full widths thereof, promptly enclosing the other lamina between the freshly extruded and heated cover laminae, and immediately bonding the cover laminae to each other at the interstices of the other lamina to embed the other lamina between the cover laminae.

14. A composite sheet material made by a method according to claim 10, comprising a pair of cover laminae of previously unused expanded polystyrene, and at least one other lamina of material having interstices formed therein, the other lamina being enclosed between the cover laminae, the cover laminae being bonded to each other at the interstices of the other lamina, whereby the other lamina is embedded between the cover laminae.