Patent Application
20080044586
To prepare the integrated dual-cure coating material systems for producing integrated internal and external paint systems (B/A) on automobile bodies first of all the dual-cure two-component systems (A1) and (A2) listed in Table 1 were prepared by mixing the constituents to their components (I) and (II) and homogenizing the resulting mixtures (I) and (II) in the absence of UV radiation. The respective components (I) and (II) were stored separately from one another prior to their use.
To prepare the integrated dual-cure coating material systems for producing integrated internal and external paint systems (B/A) on automobile bodies first of all the dual-cure two-component systems (B1) to (B5) listed in Table 2 were prepared by mixing the constituents to their components (I) and (II) and homogenizing the resulting mixtures (I) and (II) in the absence of UV radiation. The respective components (I) and (II) were stored separately from one another prior to their use.
a)solids: 65% by weight; hydroxyl number: 175 mg KOH/g; glass transition temperature: −21° C.;
b)solids: 65% by weight; hydroxyl number: 175 mg KOH/g; glass transition temperature: +11° C.;
c)urea-based SCA as per Preparation Example 3, page 11 lines 41 to 51, of DE 102 04 114 A 1 (solids: 59% by weight);
d)solids: 28.47% by weight;
e)solids: 100% by weight;
f)commercial light stabilizer from Ciba Specialty Chemicals; solids: 100% by weight;
g)commercial light stabilizer from Ciba Specialty Chemicals; solids: 85% by weight;
h)commercial coatings additive from Byk Chemie; solids: 52% by weight;
i)commercial photoinitiator from Ciba Specialty Chemicals; solids: 50% by weight;
j)commercial photoinitiator from BASF Aktiengesellschaft; solids: 10% by weight;
k)Roskydal ® UA VPLS 2337 from Bayer AG (basis: trimeric hexamethylene diisocyanate; isocyanate group content: 12% by weight; solids: 100% by weight);
l)Roskydal ® UA VP FWO 3003-77 from Bayer AG, based on the trimer of isophorone diisocyanate (solids: 70.5% by weight; isocyanate group content: 6.7% by weight);
m)polyisocyanate based on isophorone diisocyanate (Desmodur ® N 3300 from Bayer AG);
n)Isocyanato acrylate based on 4,4′-dicyclohexylmethane diisocyanate (Desmodur ® W from Bayer AG) and 4-hydroxybutyl acrylate (solids: 70% by weight; isocyanate equivalent weight 724 g).
Each of the above-described dual-cure multicomponent systems (A1) or (A2) was combinable with each of the above-described dual-cure multicomponent systems (B1), (B2), (B3), (B4) or (B5) to form an integrated dual-cure coating material system, giving a total of 10 such systems.
For the internal painting of automobile bodies beneath the trunk lid and the engine hood and in the area of the doorsills, trunk and insides of the doors and windows the dual-cure coating materials (B1) to (B5) were prepared shortly before application from the above-described dual-cure multicomponent systems (B1) to (B5) (cf. Example 1, Table 2) by mixing the respective components (I) and (II) in the following (I)/(II) mixing ratios (% by weight): (B1): 100/111; (B2): 100/111; (B3): 100/91; (B4): 100/89; (B5): 100/89.
For the external paint systems of automobile bodies the dual-cure coating materials (A1) and (A2) were prepared shortly before application from the above-described dual-cure two-component systems (A1) and (A2) (cf. Example 1, Table 1) by mixing the respective components (I) and (II) in the following (I)/(ll) mixing ratios (% by weight): (A1): 100/67; (A2): 100/65.
Automobile bodies which have been coated with a conventional electrocoat and a conventional primer-surfacer coat were coated with a commercially customary aqueous basecoat material comprising aluminum effect pigments. The aqueous basecoat films were briefly flashed off at room temperature and dried at 80° C. for 10 minutes. The wet film thicknesses were chosen so as to give film thicknesses of 12 to 15 μm after drying and curing.
The aqueous basecoat film in the interior of five automobile bodies was coated wet on wet with one each of the dual-cure coating materials (B1) to (B5), and the aqueous basecoat film on the outside was coated wet on wet with the dual-cure coating material (A1). The wet film thicknesses of the clearcoat films were set so as to give film thicknesses of 40 to 45 μm after curing.
The aqueous basecoat film in the interior of five automobile bodies was coated wet on wet with one each of the dual-cure coating materials (B1) to (B5), and the aqueous basecoat film on the outside was coated wet on wet with the dual-cure coating material (A2). The wet film thicknesses of the clearcoat films were set so as to give film thicknesses of 40 to 45 μm after curing.
The aqueous basecoat films and clearcoat films of the 10 automobile bodies were predried jointly at room temperature for 5 minutes and at 80° C. for 10 minutes, exposed to a UV radiation dose of 1500 mJ/cm2 and subsequently cured at 140° C. for 20 minutes.
The resulting internal paint systems (B) were hard and scratch-resistant, allowing installation of the further components of the automobile without any problems. The resulting external paint systems (A) were highly scratch-resistant and hard. Both paint systems had outstanding optical properties and very high light stability and chemical, water, condensation, weather and etch resistance. Their capacity for overcoating was outstanding. In particular, however, there were no longer any paint defects in the areas where the internal (B) and external (A) paint systems overlapped.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2004 023 423.6 | May 2004 | DE | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/EP05/52385 | 5/19/2005 | WO | 00 | 11/16/2006 |
