Article coated with intermingled epoxy and urethane layers

• US 5,340,652 A
• Filed: 12/10/1993
• Issued: 08/23/1994
• Est. Priority Date: 11/14/1991
• Status: Expired due to Term

• Current Assignee: Bipin C. Pant, Hemant A. Naik, Ratanjit S. Sondhe, Shirish A. Pandit
• Original Assignee: Bipin C. Pant, Hemant A. Naik, Ratanjit S. Sondhe, Shirish A. Pandit
• Inventors: Naik, Hemant A., Pandit, Shirish A., Pant, Bipin C., Sondhe, Ratanjit S.
• Primary Examiner(s): Kight, III, John
• Assistant Examiner(s): Jones, Richard
• Application Number:
  US08/165,741
• Time in Patent Office: 256 Days
• Field of Search: 428/325, 428/413, 428/414, 428/425.5, 428/425.8, 428/908.8
• US Class Current: 428/413
• CPC Class Codes: B05D 2420/01 first layer from the substrate side
• CPC Class Codes: B05D 2420/02 second layer from the substrate side
• CPC Class Codes: B05D 2503/00 Polyurethanes
• CPC Class Codes: B05D 2504/00 Epoxy polymers
• CPC Class Codes: B05D 5/063 Reflective effect B05D5/067 takes precedence
• CPC Class Codes: B05D 7/54 No clear coat specified
• CPC Class Codes: C08G 18/08 Processes
• CPC Class Codes: C08G 18/0885 using additives, e.g. absorbing agents
• CPC Class Codes: C08G 18/4009 Two or more macromolecular compounds not provided for in one single group of groups C08G18/42 - C08G18/64
• CPC Class Codes: C08G 18/4269 Lactones
• CPC Class Codes: C09D 5/004 Reflecting paints; Signal paints
• CPC Class Codes: Y10T 428/252 Glass or ceramic [i.e., fired or glazed clay, cement, etc.] [porcelain, quartz, etc.]
• CPC Class Codes: Y10T 428/31511 Of epoxy ether
• CPC Class Codes: Y10T 428/31515 As intermediate layer
• CPC Class Codes: Y10T 428/31598 Next to silicon-containing [silicone, cement, etc.] layer
• CPC Class Codes: Y10T 428/31605 Next to free metal

Abstract

An article generally comprises an epoxy base coat and a urethane top coat which has particular use for application. The epoxy composition is generally a two-part, 100 percent volatile-free system containing one or more hardeners which are reacted with an epoxy component such as the glycidyl ether of bisphenol-A. The urethane composition is also generally a two-part, 100 percent volatile-free system containing a polyisocyanate component and an intermediate component comprising a polylactone polyol, and/or a polyether polyol, a polyester polyol, or a polyether-ester polyol, an aliphatic polyol chain extender and a moisture scavenger. The two-part epoxy composition can be applied to a road with the urethane composition coated thereon whereupon it serves as a lane marker. The urethane composition has exceptional weatherability, abrasion-resistance and non-yellowing characteristics. Various reflective compounds such as glass beads can be applied thereto which are partially embedded therein and have good night as well as wet night reflective properties.

Claims

1. An article comprising a cured epoxy layer and a cured urethane layer in contact with and intermingled with said epoxy layer, said epoxy layer derived from a mixture of a two-part liquid epoxy coating composition comprising an epoxy resin part and a part of at least one epoxy hardener and containing less than 10 weight percent volatiles, said epoxy layer cured at ambient temperature or higher and having an equivalent ratio of said hardener to said epoxy resin of from 0.75 to 1.05 said urethane layer derived from the reaction mixture of a two-part urethane composition comprising a first part of an intermediate component comprising at least one polyol intermediate and optionally a moisture scavenger and a second part comprising a polyisocyanate component, said urethane layer cured at ambient temperature or higher, and said urethane composition containing less than 10 wt. % volatiles.

2. An article as set forth in claim 1, wherein said cured epoxy layer is chemically fused with said cured urethane layer, and wherein said polyisocyanate has isocyanate groups and said polyol intermediate has hydroxyl groups.

3. An article as set forth in claim 2, further including one or more reflective agents.

4. An article as set forth in claim 3, wherein said one or more reflective agents comprises glass spheres.

5. An article as set forth in claim 3, wherein said epoxy layer has a thickness of from about 5 to about 20 mils and said urethane layer has a thickness of from about 0.5 to about 10 mils.

6. An article as set forth in claim 5, wherein said epoxy layer thickness is from about 8 to about 15 mils and said urethane layer thickness is from about 0.75 to about 5 mils, and wherein the one or more reflective agents are embedded in the urethane layer.

7. An article as set forth in claim 6, wherein said epoxy layer thickness is from about 10 to about 12 mils and said urethane layer thickness is from about 2 to about 3 mils.

8. An article as set forth in claim 2, said at least one epoxy hardener comprising at least one amine or mercaptan hardener.

9. An article as set forth in claim 7, wherein said epoxy hardener comprises at least a first amine hardener (a) and a second amine hardener (b), and said amine hardener (a) is from about 10 to about 90 percent by weight of a+b and said amine hardener (b) is from about 10 to about 90 percent by weight of a+b.

10. An article as set forth in claim 9, wherein said polyol intermediate comprises a lactone polyol, a polyether polyol, a polyester polyol, or a polyether-ester polyol, or combinations thereof.

11. An article as set forth in claim 10, wherein said intermediate component further comprises a chain extender and a latent aliphatic polyamine.

12. An article as set forth in claim 2, wherein said at least one epoxy hardener comprises at least three amine hardeners, wherein the first amine hardener (a) is from about 5 to about 90 percent by weight, the second amine hardener (b) is from about 5 to about 90 percent by weight, and the third amine hardener (c) is from about 5 to about 90 percent by weight;

all percentages being based upon the weight of a+b+c and wherein said at least one polyol intermediate comprises one or more of a lactone polyol, a polyether polyol, a polyester polyol, or a polyether-ester polyol, or combinations thereof.

13. An article as set forth in claim 12, wherein the epoxy hardener comprises:

said first amine hardener which comprises a combination of an alkylphenol and an aliphatic amine which is an aminoalkyl cyclodiamine having the general formula ##STR6## wherein R¹ is an alkyl having 1 to 20 carbon atoms, and R² and R³, independently, have 1 to 15 carbon atoms and together form a heterocyclic alkyl, and where R⁴ is hydrogen or R⁵ NHR⁷ or R⁶ NHR⁷, where R⁵ is an alkyl having 1 to 10 carbon atoms, where R⁶ and R⁷, independently, are an alkyl having 1 to 10 carbon atoms, the alkyl group of said alkyl phenol having from 1 to 15 carbon atoms, and

said second amine hardener which comprises a combination of an aliphatic amine with a phenol, the aliphatic amine comprising a polygeneric amine having the general formula ##STR7## where R⁸ is (CH₂)_n, where n is 1 to 30, x is 1 to 10, and said third amine hardener has the general formula ##STR8## where R⁹ is an alkyl having 1 to 10 carbon atoms and wherein R¹⁰ is an alkyl having 1 to 10 carbon atoms, R¹¹ and R¹² independently have from 1 to 15 carbon atoms and R¹¹ and R¹² together with the two amine functionalities form a heterocyclic alkyl where R¹¹ and R¹² are each aliphatic, and R¹³ is hydrogen or R¹⁴ NH₂ or R¹⁵ NHR¹⁶, where R¹⁴ is an alkyl having 1 to 10 carbon atoms, and R¹⁵ is an alkyl having 1 to 10 carbon atoms, and R¹⁶ is an alkyl having 1 to 10 carbon atoms.

14. An article as set forth in claim 13, wherein:

the first amine hardener (a) is from about 15 to about 40 percent, the second amine hardener (b) is from about 45 to about 60 percent, and the third amine hardener (c) is from about 10 to about 25 percent, all of the foregoing percentages being by weight based on the total weight of a+b+c.

15. An article as set forth in claim 14, wherein said epoxy resin comprises from about 85 to about 95 percent of a base resin (A) and from about 5 to about 15 percent of a diluent (B), said percent being a weight percent based on the total of A and B, and said epoxy resin having a viscosity of from about 500 to about 25,000 centipoises.

16. An article as set forth in claim 15, wherein said base resin comprises the glycidyl ether of bisphenol A and said diluent comprises dibutylglycidyl ether.

17. An article as set forth in claim 16, wherein said first amine hardener comprises a combination of amino ethyl piperazine and nonyl phenol;

said second amine hardener comprises a combination of bisphenol A and diethylenetriamine, and said third amine hardener comprises nonylaminoethylpiperazine.

18. An article as set forth in claim 10, wherein said lactone polyol is made from a lactone having from 4 to 8 carbon atoms which is reacted with a polyol having from 2 to 4 hydroxyl groups and from 2 to 12 carbon atoms, wherein said polyether polyol is made from an oxyalkylene having from 2 to 6 carbon atoms, wherein said polyester polyol is made from a diol or triol, or combinations thereof, having a total of from 2 to 12 carbon atoms and a dicarboxylic acid having a total of from about 2 to about 12 carbon atoms, and wherein said polyether-ester polyol is made from one or more of said oxyalkylene, said diol or triol, or said dicarboxylic acid, and wherein the equivalent ratio of said isocyanate groups to said hydroxyl groups of said at least one polyol intermediate is from about 0.9 to about 1.5.

19. An article as set forth in claim 12, wherein said intermediate component further comprises a chain extender and wherein the amount of said lactone polyol is from about 30 parts to about 75 parts by weight for every 100 parts by weight of said intermediate component, wherein the weight average molecular weight of said lactone polyol is from about 200 to about 1,000, wherein the weight average equivalent weight of said polyether polyol, said polyester polyol, or said polyether-ester polyol is from about 190 to about 500, wherein said chain extender is a diol or a triol having from 2 to 15 carbon atoms, wherein the amount of said chain extender is from about 5 to about 25 parts by weight for every 100 parts by weight of said intermediate component;

and from about 1.0 to about 8.0 parts by weight for every 100 parts by weight of the intermediate component of said moisture scavenger.

20. An article as set forth in claim 14, wherein said polyol intermediate is said lactone polyol containing up to about 10 percent by weight of said polyether polyol, said polyester polyol, or said polyester-ether polyol, wherein said moisture scavenger is an aliphatic polyamine, an anhydride, or a molecular sieve, and wherein the equivalent ratio of said isocyanate groups to said hydroxyl groups of said at least one polyol intermediate is from about 1.02 to about 1.15.

21. An article as set forth in claim 17, wherein the amount of said epoxy composition and said urethane composition volatile component is less than 1 percent by weight, wherein said lactone polyol has from about 2.0 to about 3.0 hydroxyl groups per molecule, wherein the amount of said lactone polyol is from about 40 to about 60 parts by weight per 100 parts by weight of said polyol intermediate component;

wherein said polyisocyanate is a diisocyanate containing less than 10 percent by weight of a triisocyanate or a tetraisocyanate, wherein said polyol intermediate further comprises a chain extender and said chain extender is a diol having from 2 to 6 carbon atoms, wherein said moisture scavenger is an aliphatic polyamine, an anhydride, or a molecular sieve, wherein said aliphatic polyamine is the reaction product of an oxazolidine and a diisocyanate, and wherein said anhydride moisture scavenger is an anhydride or an alkaline earth salt thereof having a total of from 2 to 12 carbon atoms.

22. An article as set forth in claim 21, wherein said moisture scavenger is methylhexahydrophthalic anhydride or said aliphatic polyamine, wherein the weight average molecular weight of said lactone polyol is from about 275 to about 450, wherein the amount of said lactone polyol is from about 45 to about 55 parts by weight, wherein said lactone is a 2-oxepanone polymer with 2-ethyl-2 (hydroxy-methyl)-1,3-propane diol, wherein the equivalent ratio of said isocyanate groups to said hydroxyl groups of said at least one polyol intermediate is from about 1.05 to about 1.10, and wherein said urethane composition is free of volatiles having a boiling point of less than 120°

C.

25. An article as set forth in claim 1, wherein said article is a roadlane marker.

26. An article as set forth in claim 3, wherein said article is a roadlane marker.

27. An article as set forth in claim 5, wherein said article is a roadlane marker.

28. An article as set forth in claim 11, wherein said article is a roadlane marker.

29. An article as set forth in claim 13, wherein said article is a roadlane marker.

31. An article as set forth in claim 8, wherein said hardener system includes said mercaptan hardener.

32. An article as set forth in claim 31, including one or more reflective agents, and wherein said article is a roadlane marker.

33. An article as set forth in claim 3, wherein said epoxy hardener includes an amido-amine or an anhydride.

34. An article as set forth in claim 33, wherein said article is a roadlane marker.

23. An article comprising an epoxy layer and a urethane layer in contact with and intermingled with said epoxy layer, said epoxy layer comprising:

the reaction product of an epoxy resin and a hardener system, said resin having an epoxide equivalent of from about 0.2 to about 0.8, and said hardener having a free hydrogen equivalent of from about 65 to about 125, said hardener system being present in an amount of from about 0.3 to about 0.5 parts per part epoxy resin wherein said epoxy resin comprises one or more base resins of the glycidyl ether of bisphenol A, and a diluent comprising one or more epoxy resins of butyl glycidyl ether, butyl diglycidyl ether, or cresyl diglycidyl ether, said epoxy resin having a viscosity of from about 1 cps to about 30 cps and said hardener system comprising the combination of at least a first, a second, and a third amine hardener, said first amine hardener comprising the combination of an alkyl phenol and an aliphatic amine, said second amine hardener comprising the combination of a polygeneric amine and a phenol, and said third amine hardener comprising an alkyl amino alkyl cyclodiamine; and

said urethane layer comprising the reaction product of an aliphatic or aromatic polyisocyanate component and an intermediate component, said intermediate component comprising a hydroxyl terminated aliphatic polylactone, an aliphatic polyol chain extender, and a moisture scavenger.

24. An article as set forth in claim 23, wherein said epoxy layer is adhered to a substrate comprising concrete or asphalt.

30. An article as set forth in claim 23, wherein said article is a roadlane marker.