Method for forming extruded foam with surface coating
AssigneeIndustrial Thermo Ploymers Limited
InventorSteven Hartman
Life of this patent
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Abstract
An extruded foam product is manufactured with an integral thin coating of a different material on the surface thereof. The coating is applied to the product as part of the extrusion process and prior to foaming and expansion of the product using a co-extrusion die. The coating can have vastly different or specialized properties while having an inexpensive body portion. This co-extrusion arrangement simplifies the manufacturing of the product, and allows a very thin coating to be produced, if desired.
Claims11
A process for manufacturing an extruded product having a foam body portion of a first material coated with an integral surface skin of a second material fused to said foam body portion, comprising the steps of
- preparing a mixture of the material of said body portion and a foaming agent, providing said mixture to a first extruder and extruding said mixture through a main die outlet causing foaming of the body portion and a great expansion of the cross section of the body portion, generally after extrusion through said main die outlet,
- preparing in a second extruder, said second material for extrusion and forcing said second material through a ring outlet onto said first material, immediately adjacent to said main die outlet and forming an integral surface coating to said first material, prior to extrusion through said main die outlet and including adjusting the size of said ring outlet during extrusion of the product to achieve a continuous integral skin to the exterior of said foam body portion.
A process for manufacturing an extruded product having a foam body portion of a first material coated with an integral surface skin of a second material fused to said foam body portion, comprising the steps of
- preparing a mixture of the material of said body portion and a foaming agent, providing said mixture to a first extruder and extruding said mixture through a main die outlet causing forming of the body portion and a great expansion of the cross section of the body portion, generally after extrusion through said main die outlet,
- preparing in a second extruder, said second material for extrusion and forcing said second material through a ring outlet onto said first material, immediately adjacent to said main die outlet and formic an integral surface coating to said first material, prior to extrusion through said main die outlet and including adjusting the size of said ring outlet during the extrusion of the product to achieve a continuous integral skin to the exterior of said foam body portion, and
- including controlling the size of said ring outlet to achieve in the extruded product a skin thickness of said second material of less than 2 thousandths of an inch.
A process for manufacturing an extruded product having a foam body portion of a first material coated with an integral surface skin of a second material fused to said foam body portion, comprising the steps of
- preparing a mixture of the material of said body portion and a foaming agent, providing said mixture to a first extruder and extruding said mixture through a main die outlet causing foaming of the body portion and a great expansion of the cross section of the body portion, generally after extrusion through said main die outlet,
- preparing in a second extruder, said second material for extrusion and for said second material through a ring outlet onto said first material, immediately adjacent to sid main die outlet and forming an integral surface coating to said first material, prior to extrusion through said main die outlet and including adjusting the size of said ring outlet during the extrusion of the product to achieve a continuous integral skin to the exterior of aid foam body portion, and
- including controlling the size of said ring outlet to achieve in the extruded product a skin thickness of said second material of less than 1 thousandths of an inch.
Dependencies are inferred from the claim text.