Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – At least one aryl ring which is part of a fused or bridged...
Patent
1994-03-04
1996-09-03
Seidleck, James J.
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
At least one aryl ring which is part of a fused or bridged...
524591, 524839, 528 71, C08L 7504, C08L 7506, C08G 1842
Patent
active
055524770
DESCRIPTION:
BRIEF SUMMARY
The present invention relates to a novel aqueous coating agent based on a polyol component present dissolved and/or dispersed in water, consisting of one high-molecular polymerization resin or polycondensation resin and a reactive diluent and a polyisocyanate component present emulsified in it, a method for producing such coating agents and their use for the production of coatings.
Aqueous lacquer systems are gaining increasingly in importance on economic and ecological grounds. The replacement of conventional lacquer systems is however proceeding more slowly than was initially expected.
There are numerous reasons for this. Thus aqueous dispersions frequently still have disadvantages with regard to processing when compared with lacquer systems dissolved in organic solvents. In aqueous solutions, however, there is the problem of adequate solubility in water on the one hand as well as the opposite effect derived from it of lower water resistance of the coatings compared with conventionally dissolved lacquer systems. Added to this there are processing problems which in many cases result from the high viscosity and anomalies of viscosity and which hitherto have been surmounted by using organic solubilising agents. The quantity of solubilising agent that can be used for this is limited, as otherwise the ecological purpose of aqueous systems is defeated.
For this reason there were used in melamine resin cross-linked binder systems reactive diluents that were already water-dilutable (U.S. Pat. Nos. 4,031,052, 4,171,294, 4,276,210 or DE-OS 2,446,760 or 2,847,532) which on one hand favourably influence the solubility of the polymer systems but on the other hand became incorporated into the coatings through melamine resin cross-linking. However the reactivity of many aqueous melamine resins is so low that in many cases the cross-linking temperatures required are so high that the reactive diluents can escape from the coatings prior to cross-linking.
Quite recently aqueous two-component polyurethane systems have become known (DE-OS 3,829,587) with a binder consisting of a polyacrylic resin present dissolved and/or dispersed in water combined with a polyisocyanate with free isocyanate groups present emulsified in this dispersion or solution. Here it concerns essentially solvent-free systems, which is already evident from the fact that the solvents which were used in the preparation of the polymer resins are removed prior to producing the aqueous preparation. The concomitant use of reactive diluents is not discussed in the reference cited above.
Surprisingly it was then found that the use of reactive diluents, i.e. of low-molecular, not easily volatilised, liquid compounds with groups capable of reacting with isocyanate groups of the kind described in more detail below in aqueous two-component polyurethane systems based on high-molecular polymerization resins or polycondensation resins possessing hydroxyl groups and polyisocyanates, with free isocyanate groups result in a considerable improvement in systems as regards the dilutability in water of the components of the binder and the properties of the lacquer coatings produced from the binding agents. These advantages need not be acquired at the expense of the ecological disadvantage of usual solvents, as the non-volatile reactive diluents are incorporated in the lacquer film when the coating agent is processed.
The present invention provides coating agents, whose binder consists essentially of a combination of to 10,000 mPa.s present emulsified in the aqueous solution and/or dispersion of the polyol component a) groups of component b) to active hydrogen atoms of component a) of from 0.5: 1 to 5: 1, characterised in that component a) consists essentially of a combination of one water-dilutable polymerization resin or polycondensation resin with a molecular weight Mn of over 500 possessing hydroxyl groups with reactive diluent consisting of at least one water-soluble compound that is not distillable at normal pressure or that has a boiling point of at least 150.degree. C.
REFERENCES:
patent: 3477977 (1969-11-01), Schnell et al.
patent: 4007151 (1977-02-01), Ogawa et al.
patent: 4031052 (1977-06-01), Dhein et al.
patent: 4171294 (1979-10-01), Dhein
patent: 4276210 (1981-06-01), H ohlein et al.
patent: 4594385 (1986-06-01), Thoma et al.
patent: 4609572 (1986-09-01), Gruber et al.
patent: 4652466 (1987-03-01), Thoma et al.
patent: 4659780 (1987-04-01), Stamegna et al.
patent: 4801644 (1989-01-01), Coogan
patent: 4861826 (1989-08-01), Hummerich et al.
patent: 4871798 (1989-10-01), Dormish et al.
patent: 4895894 (1990-01-01), Ruetman et al.
patent: 4977207 (1990-12-01), Hoefer et al.
patent: 5039733 (1991-08-01), Dormish et al.
patent: 5075370 (1991-12-01), Kubitza et al.
patent: 5194487 (1993-03-01), Jacobs
patent: 5308912 (1994-05-01), Margotte et al.
patent: 5336711 (1994-08-01), Schneider et al.
patent: 5344873 (1994-09-01), Blum
patent: 5387642 (1995-02-01), Blum et al.
patent: 5459197 (1995-10-01), Schwindt et al.
B acker Lothar
Bock Manfred
Dhein Rolf
Kubitza Werner
Probst Joachim
Bayer Aktiengesellschaft
Gil Joseph C.
Roy Thomas W.
Seidleck James J.
Sergent Rabon
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