Coating processes – Applying superposed diverse coating or coating a coated base – Synthetic resin coating
Patent
1992-07-28
1994-06-21
Beck, Shrive
Coating processes
Applying superposed diverse coating or coating a coated base
Synthetic resin coating
4274121, 4274191, B05D 714
Patent
active
053227158
DESCRIPTION:
BRIEF SUMMARY
The invention relates to a process for the production of a multicoat protective and/or decorative coating on a substrate surface, in which process material a water-thinnable emulsion polymer is applied to the substrate surface as the basecoat coating composition basecoat obtained in this manner and subsequently 80.degree. C.
The present invention also relates to a process for the production of a multicoat protective and/or decorative coating on a substrate surface in the automotive refinishing sector, in which process material a water-thinnable emulsion polymer is applied to the substrate surface as the basecoat coating composition basecoat obtained in this manner and subsequently 100.degree. C.
The process, described above, for the production of multicoat protective and/or decorative coatings is known and is employed in particular for the production of effect finishes on automobile bodies (cf. for example EP-A-89,497, DE-A-3,628,124 and EP-A-38,127).
With the process under discussion it is possible to produce metallic effect finishes having a good metallic effect only if the composition of the aqueous basecoat coating compositions employed is such that they can be applied to the substrate in relatively thin films. which dry rapidly at low temperatures below 100.degree. C. and which, after stages (3) and (4) of the process have been carried out, have the metal pigment particles arranged in a direction parallel with the surface of the substrate.
Furthermore, the composition of the aqueous basecoat coating compositions must be such that the basecoat of the metallic finishes adheres well to the substrate and the transparent topcoat adheres well to the basecoat. In addition, the composition of the aqueous basecoat coating compositions must be such that the dried metallic effect finish suffers no loss of gloss, loss of adhesion or even blistering after exposure to a condensation-water cycling test.
It is finally desirable that the aqueous basecoat coating compositions exhibit a long shelf life. In addition, the individual binders and/or paint components stored under certain circumstances in an anhydrous state must still be homogeneously miscible after storage.
Aqueous basecoat coating compositions which contain as the film-forming material a mixture of a water-thinnable emulsion polymer and a water-thinnable polyurethane resin, are disclosed in DE-A-3,628,124. These basecoat coating compositions do not comply with the above requirements in an optimum manner, in particular as regards drying temperatures <100.degree. C.
Furthermore, a process for the formation of coatings is known from German Patent 3,600,425, in which process a priming composition and a topcoat composition are applied and the coatings are cured in a temperature range between room temperature and about 140.degree. C. The primer contains a resin of a given molecular weight range having a hydroxyl group or a hydroxyl and a carboxyl group in the molecule as well as a catalyst, if appropriate. The curing component is contained in the topcoat and not in the primer.
A process for the formation of multicoat coatings is known from EP-A-287,144, in which process the basecoat contains a dispersion of an emulsion polymer produced by a 2-stage process. In the first stage of this process high proportions, however, of 65 to 100 mol % of (cyclo)alkyl esters of (meth)acrylic acid and, if appropriate, of fumaric and/or maleic acid are employed, in which case the (cyclo)alkyl radical comprises 4 to 12 carbon atoms, as a result of which the resultant polymers have very low Tg values. Furthermore, in the second stage high proportions of 10 to 60 mol % of (meth)acrylic acid are employed, as a result of which the resultant polymers have very high acid values.
Finally, a process is described in Patent Application DE 3,841,540, not yet published, in which a water-thinnable basecoat and, after a brief flash-off period, a topcoat coating composition is applied. This process differs from the present process in that in the DE 3,841,540 process the basecoat is baked toget
REFERENCES:
patent: 3823205 (1974-07-01), Zimmt
patent: 3998768 (1976-12-01), Pettit, Jr.
patent: 4150005 (1979-04-01), Gehman et al.
patent: 4151143 (1979-04-01), Blank et al.
patent: 4385152 (1983-05-01), Boyack et al.
patent: 4973621 (1990-11-01), Buter
Jouck Walter
Mayer Bernd
Wieditz Stefan C.
BASF Lacke+Farber Aktiengesellschaft
Beck Shrive
Cameron Erma
Sabourin Anne Gerry
LandOfFree
Process for production of a multicoat coating does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process for production of a multicoat coating, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for production of a multicoat coating will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2219685