CLOSED-CELL URETHANE SHEET, MANUFACTURING METHOD THEREOF AND WATERPROOF SEALING MATERIALS

• US 20100028650A1
• Filed: 07/29/2009
• Published: 02/04/2010
• Est. Priority Date: 07/31/2008
• Status: Abandoned Application

• Current Assignee: NHK Spring Company Limited
• Original Assignee: NHK Spring Company Limited
• Inventors: Yoshioka, Minoru, Kawaguchi, Hiromasa, KUSAKAWA, Koichi, Sera, Noriyuki
• Application Number:
  US12/511,356
• Publication Number:
  US 20100028650A1
• Time in Patent Office: Days
• US Class Current: 428/314.400
• CPC Class Codes: B32B 2250/02 2 layers
• 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 2307/304 Insulating
• CPC Class Codes: B32B 2307/7265 Non-permeable
• CPC Class Codes: B32B 2419/00 Buildings or parts thereof walls, panels B32B2607/00
• CPC Class Codes: B32B 2457/00 Electrical equipment
• CPC Class Codes: B32B 2581/00 Seals; Sealing equipment; Gaskets
• CPC Class Codes: B32B 2605/08 Cars
• CPC Class Codes: B32B 27/08 of synthetic resin
• CPC Class Codes: B32B 27/283 comprising polysiloxanes
• CPC Class Codes: B32B 27/32 comprising polyolefins comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30
• CPC Class Codes: B32B 27/36 comprising polyesters
• CPC Class Codes: B32B 27/40 comprising polyurethanes
• CPC Class Codes: B32B 7/06 permitting easy separation
• CPC Class Codes: C08G 18/10 Prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step
• CPC Class Codes: C08G 18/42 Polycondensates having carboxylic or carbonic ester groups in the main chain
• CPC Class Codes: C08G 18/4233 derived from polymerised higher fatty acids or alcohols
• CPC Class Codes: C08G 18/4825 Polyethers containing two hydroxy groups C08G18/4833 - C08G18/5096 take precedence
• CPC Class Codes: C08G 2110/0008 flexible
• CPC Class Codes: C08G 2110/0083 : prepared using water as the sole blowing agent
• CPC Class Codes: C08J 2203/22 : Expandable microspheres, e.g. Expancel®
• CPC Class Codes: C08J 2205/052 : Closed cells, i.e. more than 50% of the pores are closed
• CPC Class Codes: C08J 2375/04 : Polyurethanes
• CPC Class Codes: C08J 9/32 : from compositions containing microballoons, e.g. syntactic foams
• CPC Class Codes: C08L 75/06 : from polyesters
• CPC Class Codes: C08L 91/06 : Waxes
• CPC Class Codes: Y10T 428/249921 : Web or sheet containing structurally defined element or component
• CPC Class Codes: Y10T 428/249976 : Voids specified as closed

Abstract

A method of manufacturing a closed-cell urethane sheet, the method includes the steps of mixing a liquid urethane raw material with thermally expandable microcapsules to obtain a liquid urethane foam raw material, coating the liquid urethane foam raw material on at least one of the opposite surfaces of a releasable substrate to form a urethane raw material sheet, and heating the urethane raw material sheet from the opposite surfaces of the urethane raw material sheet to expand and cure the urethane raw material sheet to obtain the closed-cell urethane sheet.

Claims

1. A method of manufacturing a closed-cell urethane sheet, the method comprising the steps of:

mixing a liquid urethane raw material with thermally expandable microcapsules to obtain a liquid urethane foam raw material;

coating the liquid urethane foam raw material on at least one of the opposite surfaces of a releasable substrate to form a urethane raw material sheet; and

heating the urethane raw material sheet from the opposite surfaces of the urethane raw material sheet to expand and cure the urethane raw material sheet to obtain the closed-cell urethane sheet.

2. The method according to claim 1, wherein the liquid urethane foam raw material is formulated to further contain an auxiliary foaming agent in addition to the thermally expandable microcapsules.

3. A waterproof sealing material which is formed of a sheet-like closed-cell urethane to be obtained from the foaming/curing of a liquid urethane raw material containing thermally expandable microcapsules, the sheet-like closed-cell urethane being accompanied, on at least one of the opposite surfaces thereof, with a skin layer exhibiting a contact angle of at least 90°

.

4. A closed-cell urethane sheet which is useful as a sealing material and is created from a mixture comprising a liquid urethane raw material and thermally expandable microcapsules, wherein the liquid urethane raw material is an isocyanate-terminated urethane prepolymer representing a reaction product to be obtained from the reaction of dimer acid-based polyol, low molecular glycol and isocyanate, and that the closed-cell urethane sheet is enable to exhibit a contact angle of at least 90°

.

5. A method of manufacturing a closed-cell urethane sheet, the method comprising the steps of:

mixing a liquid urethane raw material with thermally expandable microcapsules to obtain a liquid urethane foam raw material wherein the liquid urethane raw material is an isocyanate-terminated urethane prepolymer representing a reaction product to be obtained from the reaction of a dimer acid-based polyol, a low molecular glycol and isocyanate;

coating the liquid urethane foam raw material on at least one of the opposite surfaces of a releasable substrate to form a urethane raw material sheet; and

heating the urethane raw material sheet to expand and cure the urethane raw material sheet to obtain the closed-cell urethane sheet.