Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – Mixing of two or more solid polymers; mixing of solid...
Patent
1983-10-13
1985-07-23
Pertilla, Theodore E.
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
Mixing of two or more solid polymers; mixing of solid...
4284231, 4284237, 4284258, 525443, 525456, 525457, C08L 7506
Patent
active
045309760
DESCRIPTION:
BRIEF SUMMARY
Reference is made to concurrently filed and commonly assigned related U.S. applications Ser. No. 553,322 entitled "Flexible Coating Compositions", U.S. application Ser. No. 592,124 entitled "Flexible Basecoat/Clearcoat Coating Compositions", both to Alexander et al; U.S. application Ser. No. 558,399 entitled "Flexible Two Component Urethane Coating Compositions", U.S. application Ser. No. 555,463 entitled "Flexible Basecoat/Two Component Clearcoat Coating Compositions", abandoned in favor of CIP application Ser. No. 615,700 filed May 29, 1984; all to Kordomenos et al. This invention relates to flexible coating systems which have excellent adherence to metal and plastic substrates and posses superior weathering properties. Basecoat/clearcoat systems comprise a finish of a clear topcoat layer in film adherence to a basecoat that is in adherence to a substrate. More particularly, the invention relates to a basecoat/clearcoat coating composition wherein the basecoat and the clearcoat composition each comprise hydroxy-containing urethane modified polyesters, made from urethane modified diols reacted with polyol and diacid component, crosslinking agent and, optionally, a high molecular weight linear polyurethane. The basecoat, which additionally contains pigment, employs amine-aldehyde crosslinking agent while the clearcoat employs polyisocyanate crosslinking agent.
BACKGROUND ART
Recently, there has been interest in the use of rubbery resilient materials for areas which are subject to mechanical shock such as automobile bumpers, moldings and front ends. The use of such materials aids in providing protection from permanent structural damage but, in order to attain the desired appearance, a protective coating must have unique properties, such as a high degree of extensibility, impact resistance, resistance to cracking under severe environmental conditions, such as exposure to low temperature and low humidity. Conventional coatings, including those employed on rubber and similar extensible objects heretofore, do not have the required combination of properties. Generally compositions that are flexible enough to be applied over both metal and plastic substrates have rather poor weatherability and overall durability.
U.S. Pat. No. 3,882,189 and U.S. Pat. No. 3,962,522 are exemplary of numerous patents which describe flexible coating compositions wherein the resin comprises polyurethane modified polyesters formed by reacting polyisocyanate with polyester polyols. These resins are cured with amine aldehyde crosslinkers. It is taught therein, that the presence of the urethane groups in the polymer significantly contributes to the flexibility as well as improved weathering properties, gloss, and abrasion resistance of the coating. However, while it is thus desirable to employ a substantial number of urethane groups in these resins, the amount which may be included in these types of resins is limited. When hydroxy polyester resin is reacted with polyisocyanate it has a tendency to form a gelled mass and thus the amount of polyisocyanate that may be employed must be restricted in order to avoid gelation. Still further, these urethane linkages are added in a latter modification of the polyester polyol reaction product, rather than being incorporated into the backbone of the resin.
DISCLOSURE OF THE INVENTION
This invention is directed to a flexible basecoat/clearcoat coating composition which is suitable for use over various substrates, including rubbery, resilient materials as well as metal. The basecoat/clearcoat coating composition of this invention is characterized in that the basecoat composition and the clearcoat composition each independently comprises:
(A) hydroxy-containing urethane modified polyester (i) having a number average molecular weight (M.sub.n) of between about 1000 and about 10,000 (ii) having a hydroxyl number of between about 30 and about 200, and (iii) containing between about 1 to about 10 urethane groups per molecule, and being made from reactants comprising: wherein the diol and diisocyanate
REFERENCES:
patent: 3763079 (1973-10-01), Fryd
patent: 3882189 (1975-05-01), Hudak
patent: 3954899 (1976-04-01), Chang et al.
patent: 3962522 (1976-06-01), Chang et al.
patent: 4017456 (1977-04-01), Tucker et al.
patent: 4021505 (1977-05-01), Wang
patent: 4034017 (1977-07-01), Chang et al.
patent: 4205115 (1980-05-01), Piccirilli et al.
patent: 4208495 (1980-06-01), Chang et al.
Alexander Delores J.
Kordomenos Panagiotis I.
Kurple Kenneth R.
Ford Motor Company
May Roger L.
Melotik Lorraine S.
Pertilla Theodore E.
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