Water based plasticizer free polyurethane-wax coating and repair composition and method

• US 6,228,926 B1
• Filed: 12/13/1999
• Issued: 05/08/2001
• Est. Priority Date: 08/04/1997
• Status: Expired due to Fees

• Current Assignee: Harvey J. Golumbic, June Ruth Golumbic
• Original Assignee: GOLUMBIC, HARVEY J. AND GOLUMBIC, JUNE RUTH
• Inventors: Golumbic, Harvey J.
• Primary Examiner(s): Szekely, Peter
• Application Number:
  US09/459,844
• Time in Patent Office: 512 Days
• Field of Search: 524/104, 524/275, 524/276, 524/478, 524/479, 524/480, 524/487, 524/488, 524/489, 524/507, 524/591, 428/423.1, 428/423.4, 428/424.6, 427/385.5, 427/389, 427/393.5
• US Class Current: 524/489
• CPC Class Codes: C08L 91/06 Waxes
• CPC Class Codes: C09D 175/04 Polyurethanes
• CPC Class Codes: Y10T 428/31551 Of polyamidoester [polyurethane, polyisocyanate, polycarbamate, etc.]

Abstract

A coating composition comprising a colloid of a thermoplastic, elastomeric polyurethane and a wax dispersible in water is applied to the surface of a substrate, drying rapidly to form a tough, durable, protective film bonded firmly to the surface.

Claims

1. A product comprising

a substrate having a surface covered by

a solid, thin film which adheres firmly to the surface and is formed upon evaporation of water after the application of a non-toxic, water-based, colloidal coating composition which is essentially free of plasticizers as separate additives, said film consisting essentially of a wax having a softening point between 180°

and 290°

F. and a thermoplastic, elastomeric polyurethane which is a blend of at lest two polyurethanes including a base polyurethane having an elongation of approximately 400 percent mixed with either (1) a relatively hard polyurethane having an elongation of approximately 150 percent or (2) a relatively soft polyurethane having an elongation of approximately 700 percent depending on the application,

said film having a thickness ranging between 5 and 100 microns.

2. A coating composition which is essentially free of plasticizers as separate additives and consists essentially of from 20 to 55 weight percent of a thermoplastic, elastomeric polyurethane, from 1 to 5 weight percent of a wax dispersible in water and having a softening point between 180 and 290 F, from 1 to 30 weight percent of a dispersing agent, and the balance water where the ratio of water to dispersing agent is from 20/80 to 10/90 by volume, said polyurethane being a blend of at least two polyurethanes with substantially different elongations.

3. A method of protecting the surface of a substrate, comprising:

applying to said surface a thin coating of a water based, colloidal coating composition which is essentially free of plasticizers as separate additives, and

drying the coating to evaporate the water, so that a film is formed on the surface which is bonded firmly to said surface and has a thickness ranging between 5 and 100 microns,

said film consisting essentially of a thermoplastic, elastomeric polyurethane and a wax dispersible in water having a softening point between 180 and 290 F, said elastomeric polyurethane being a blend of at least two polyurethanes with substantially different elongations.

4. The method of claim 3 where the blend of at least two polyurethanes includes a base polyurethane having an elongation of approximately 400 percent mixed with either (1) a relatively hard polyurethane having an elongation of approximately 150 percent or (2) a relatively soft polyurethane having an elongation of approximately 700 percent depending on the application.