SOLVENT-CONTAINING EMULSIFIED ALKYD RESIN COATING COMPOUND FOR STAIN AND VARNISH COATINGS

Abstract

A solvent-containing coating compound for stains and varnish coatings, in particular for house varnishes or components thereof, containing or consisting of at least one oxidatively drying organic binder, selected from the group consisting of at least one oxidatively drying middle oil and/or long oil alkyd resin, in particular an oxidatively drying long oil alkyd resin, at least one primary drier based on iron, in particular comprising or consisting of at least one organic salt of iron and/or a coordination complex of iron, in particular a complex salt of iron, at least one first secondary drier, in particular comprising or consisting of at least one organic and/or inorganic salt or a compound of zirconium, magnesium, calcium, strontium, barium, zinc, lithium or aluminium, solvent, water, at least one emulsifying agent, optionally, at least one conventional additive.

Claims

1. A solvent-containing coating compound for varnish coatings and stains, in particular for house varnishes or components thereof, containing or consisting of at least one oxidatively drying organic binder, selected from the group consisting of at least one oxidatively drying middle oil and/or long oil alkyd resin, in particular an oxidatively drying long oil alkyd resin, at least one primary drier based on iron, in particular comprising or consisting of at least one organic salt of iron and/or a coordination complex of iron, in particular a complex salt of iron, at least one first secondary drier, in particular comprising or consisting of at least one organic and/or inorganic salt or a compound of zirconium, magnesium, calcium, strontium, barium, zinc, lithium or aluminium, solvent, water, at least one emulsifying agent, optionally, at least one conventional additive.

2. The coating compound as claimed in claim 1, further comprising at least one second secondary drier comprising or consisting of at least one organic salt of calcium, zirconium and any mixture thereof, wherein the first and the second secondary drier are different.

3. The coating compound as claimed in claim 1, which is substantially free from cobalt and manganese compounds, in particular free from siccatives based on cobalt and manganese.

4. The coating compound as claimed in claim 1, characterized in that the oxidatively drying organic binder further comprises at least one oxidatively drying modified middle oil and/or long oil alkyd resin, in particular selected from the group consisting of siliconized alkyd resins, acrylated alkyd resins, isocyanate-modified alkyd resins and any mixtures thereof, in particular isocyanate-modified long oil alkyd resins.

5. The coating compound as claimed in claim 1, characterized in that the solvent comprises or consists of, in particular, aromatics-free aliphatic hydrocarbons, preferably selected from the group consisting of, in particular, dearomatized white spirit, n-paraffins, isoparaffins, cycloparaffins and any mixtures thereof, and preferably contains methoxypropoxypropanol as a co-solvent

6. The coating compound as claimed in claim 1, characterized in that the additive is selected from the group consisting of defoaming agents, light stabilizers, radical scavengers, wetting agents, dispersing agents, surface additives, in particular silicone surface additives, for example polyether-modified polymethylalkylsiloxane and/or silicone polyether copolymers and/or surface active polyacrylates, matting agents, in particular waxes, and any mixtures of these compounds.

7. The coating compound as claimed in claim 1, characterized in that the organic salt of the first and/or second secondary driers comprises neodecanoates, oleates, stearates, palmitates, octoates and/or naphthenates, in particular neodecanoates, particularly preferably zirconium neodeconoate and/or strontium neodecanoate.

8. The coating compound as claimed in claim 1, characterized in that the long oil fraction of the oxidatively drying long oil alkyd resins is based on linoleic acid, linolenic acid, oleic acid and palmitic acid, and/or in that the middle oil fraction of the oxidatively drying middle oil alkyd resins is based on linoleic acid, linolenic acid and/or oleic acid and optionally with the addition of palmitic acid, in particular linoleic acid, linolenic acid, oleic acid and palmitic acid.

9. The coating compound as claimed in claim 1, characterized in that the coating compound is substantially free from amorphous silicon dioxide and SiO.sub.2 based compounds.

10. The coating compound as claimed in claim 1, characterized in that the fraction of the primary drier based on iron, with respect to its metallic fraction, is in the range of 0.0001 to 0.3 percent by weight, preferably in the range of 0.0001 to 0.1 percent by weight and particularly preferably in the range of 0.0001 to 0.05 percent by weight, respectively with respect to the total weight of the coating compound, the fraction of the at least one first secondary drier comprising or consisting of at least one organic salt of zirconium, strontium, calcium, magnesium, barium, zinc, lithium and/or aluminium, with respect to its metallic fraction, is in the range of 0.005 to 1.5 percent by weight, preferably in the range of 0.025 to 1.0 percent by weight and particularly preferably in the range of 0.05 to 0.8 percent by weight, respectively with respect to the total weight of oxidatively drying organic binder, and/or in that the fraction of the at least one second secondary drier comprising or consisting of at least one organic salt of calcium, lithium, zirconium and any mixture, with respect to its metallic fraction, is herein in the range of 0.005 to 1.5 percent by weight, preferably in the range of 0.01 to 3.0 percent by weight and particularly preferably in the range of 0.025 to 0.8 percent by weight, respectively with respect to the total weight of oxidatively drying organic binders, and/or in that the fraction of solvent is in the range of 0.1 to 40 percent by weight, preferably 0.2 to 35 percent by weight and particularly preferably in the range of 3 to 30 percent by weight, with respect to the total weight of the coating compound.

11. The coating compound as claimed in claim 1, with a content of at least one emulsifying agent, preferably a polymeric emulsifying agent and particularly preferably an emulsifying agent based on a film-forming polysaccharide resin, especially in a quantity for use of 0.1-10% by weight, preferably 0.2-8% by weight, more preferably 0.25-5% by weight.

12. The coating compound as claimed in claim 1, with a water content of 2-40% by weight, preferably 3-35% by weight, more preferably 4-30% by weight, most preferably 4-10% by weight.

13. The coating compound as claimed in claim 1, with a pigment-volume concentration (PVC) according to EN ISO 4618-1 of 0 to 50%, more preferably 2 to 45%, particularly preferably 4 to 40%.

14. A coating on a substrate, in particular a cover coating, primer, primer-/topcoat-1-pot coating or transparent or semi-transparent final coating, obtained or obtainable by application of, and physical or chemical drying of, the coating compound in accordance with claim 1.

15. The coating as claimed in claim 14, characterized in that it has an average, in particular absolute, dry layer thickness, determined in accordance with DIN EN ISO 2808-2 (May 2017), which is not over 100 m, preferably not over 80 m and particularly preferably in the range of 5 to 60 m.

16. Use of a coating compound in accordance with claim 1, for the production of stains and varnish coatings.

17. A method for the production of a coating compound in accordance with claim 1, in which firstly, a water-in-oil emulsion is produced from alkyd resin, solvent, water and emulsifying agent as well as optional additives such as defoaming agents and deaerators, and in order to produce the coating compound, this is then combined with an appropriate proportion of a conventional solvent-containing and water-free alkyd resin formulation.

Description

EXEMPLARY EMBODIMENT 1

[0094] White Varnish, Satin Finish: In Accordance with the Invention

TABLE-US-00001 Alkyd resin 20% by weight Thixotropic alkyd resin 2% by weight Water 8% by weight Emulsifying agent 1% by weight Fillers 16% by weight Pigments/colorants 32% by weight Additives: wetting agents/dispersing 4.8% by weight agents, deaerators, defoaming agents, slip additives/free flow additives, anti-skinning agents, light stabilizers, radical scavengers, etc. Matting agent (PE-wax) 3.0% by weight Solvent 12.8% by weight Iron primary drier 0.0003% by weight (with respect to the metallic fraction) Zirconium siccative (auxiliary drier) 0.2% by weight Calcium siccative (through drier) 0.2% by weight

[0095] White Varnish, Satin Finish: Reference Example 1

TABLE-US-00002 Alkyd resin 24% by weight Thixotropic alkyd resin 2% by weight Fillers 16% by weight Pigments/colorants 32% by weight Additives: wetting agents/dispersing agents, 4.8% by weight deaerators, defoaming agents, slip additives/free flow additives, anti-skinning agents, light stabilizers, radical scavengers, etc. Matting agent (amorphous silica) 3.0% by weight Solvent 17.8% by weight Iron primary drier 0.0003% by weight (with respect to the metallic fraction) Zirconium siccative (auxiliary drier) 0.2% by weight Calcium siccative (through drier) 0.2% by weight

[0096] Reference Example 1 contained no water and therefore also contained no emulsifier. The matting agent polyethylene wax was exchanged for amorphous silica.

[0097] In Reference Example 2, in the formulation in accordance with the invention for the satin finish white varnish, the polyethylene wax matting agent was exchanged for amorphous silica; in addition, instead of the iron primary drier, a conventional cobalt primary drier was employed in the usual quantity.

[0098] The coating compounds (in accordance with the invention, Reference Example 1 and Reference Example 2) were applied with a 75 m doctor blade and tested with a Drying Recorder.

[0099] The coating composition in accordance with the invention was sufficiently dry after approximately 3.5 hours; that of Reference Example 2 after approximately 8 hours. In contrast, Reference Example 1 was still not dry after 24 hours, and so the test was stopped.

EXEMPLARY EMBODIMENT 2

[0100] White Surface Varnish: In Accordance with the Invention

TABLE-US-00003 Alkyd resin 28% by weight Thixotropic alkyd resin 12% by weight Water 14% by weight Emulsifying agent 2% by weight Pigments/colorants 8% by weight Additives: wetting/dispersing 3.6% by weight agents, deaerators, defoaming agents, slip additives/free flow additives, anti-skinning agents, light stabilizers, radical scavengers, etc. Matting agent 2.0% by weight Solvent 30% by weight Iron primary drier 0.0004% by weight (with respect to the metallic fraction) Zirconium siccative (auxiliary drier) 0.25% by weight Calcium siccative (through drier) 0.15% by weight

[0101] The coatings obtained from the coating compounds in accordance with the invention did not display any tendencies to discolouration. It is also of practical relevance to obtain film hardnesses with the coating compounds in accordance with the invention, as usually obtained when employing conventional cobalt-based primary driers.

[0102] A further advantage of the coating compounds in accordance with the invention is the reduction in the VOC content. Less solvent has to be used, because a portion thereof is substituted with water. As a matter of fact, for example, with the coating compounds in accordance with the invention for decorative applications, VOC values of less than 300 g/L were obtained. In order to determine the volatile organic compounds content (VOC content), DIN EN ISO standard 11890-1 (September 2007) may be employed.