Additive for improving the early resistance to driving rain of coating compositions and the use thereof

• US 20100010134A1
• Filed: 07/02/2009
• Published: 01/14/2010
• Est. Priority Date: 07/08/2008
• Status: Active Grant

• Current Assignee: Hilti Aktiengesellschaft (Hilti Martin Family Trust)
• Original Assignee: Hilti Aktiengesellschaft (Hilti Martin Family Trust)
• Inventors: Muenzenberger, Herbert, Simon, Sebastian, Foerg, Christian, Gebauer, Klaus
• Granted Patent: US 7,897,669 B2
• Time in Patent Office: Days
• US Class Current: 524/317
• CPC Class Codes: C08K 5/053 Polyhydroxylic alcohols
• CPC Class Codes: C08K 5/103 with polyalcohols
• CPC Class Codes: C08L 79/02 Polyamines
• CPC Class Codes: C09D 133/02 Homopolymers or copolymers of acids; Metal or ammonium salts thereof
• CPC Class Codes: C09D 5/18 Fireproof paints including high temperature resistant paints
• CPC Class Codes: C09D 7/20 Diluents or solvents
• CPC Class Codes: C09D 7/40 Additives

Abstract

An additive for improving the early resistance to driving rain of physically curing coating compositions based on an aqueous acrylate dispersions, which have been adjusted to an alkaline pH with an inorganic or organic base, which is volatile at ambient temperature, is formed of an aqueous dispersion, containing a polyethyleneimine with a number average molecular weight in the range from 50,000 to 3,000,000, at least one representative of the group comprising 1,3-dihydroxy-2,2,4-trimethylpentane and esters thereof, butyl diglycol acetate and methoxypropanol as film-forming agents and at least one representative of the group comprising the liquid acrylates and pyrogenic silica as thickening agent, as well as optionally a pigment and optionally an ammonium acrylate as pigment disperser, and the use thereof.

Claims

1. An additive for improving the early resistance to driving rain of physically curing coating compositions based on an aqueous acrylate dispersions, which have been adjusted to an alkaline pH with an inorganic or organic base, which is volatile at ambient temperature, characterized by an aqueous dispersion, containing a polyethyleneimine with a number average molecular weight in the range from 50,000 to 3,000,000, at least one representative of the group comprising 1,3-dihydroxy-2,2,4-trimethylpentane and esters thereof, butyl diglycol acetate and methoxypropanol as film-forming agents and at least one representative of the group comprising the liquid acrylates and pyrogenic silica as thickening agent, as well as optionally a pigment and optionally an ammonium acrylate as pigment disperser.

2. The additive of claim 1, characterized in that it contains a polyethyleneimine with a number average molecular weight in the range from 500,000 to 2,500,000.

3. The additive of claim 1, characterized in that it contains at least one representative of the group comprising 1,3-dihydroxy-2,2,4-trimethylpentane, 1,3-dihydroxy-2,2,4-trimethylpentane monopropionate, 1,3-dihydroxy-2,2,4-trimethylpentane dipropionate, 1,3-dihydroxy-2,2,4-trimethylpentane monoiso-propionate, 1,3-dihydroxy-2,2,4-trimethylpentane diisopropionate, 1,3-dihydroxy-2,2,4-trimethylpentane monobutyrate, 1,3-dihydroxy-2,2,4-trimethyl-pentane dibutyrate, 1,3-dihydroxy-2,2,4-trimethylpentane monoiso-butyrate and 1,3-dihydroxy-2,2,4-trimethylpentane diisobutyrate as film-forming agents.

4. The additive of claim 1, characterized in that, as liquid acrylate, it contains an aqueous solution of an acrylate copolymer with a solids content of 20 to 40% by weight and preferably of 30% by weight, a density of 1.06 and a pH of about 3.

5. The additive of claim 1, characterized in that it contains an organic and/or inorganic pigment, preferably Fe₃O₄ or carbon black.

6. The additive of claim 1, characterized in that it contains an ammonium acrylate, with a solids content of 35% and a pH between 7.5 and 9.5, as pigment disperser.

7. The additive of claim 1, characterized by an aqueous dispersion, containing 42.7 to 46.7% by weight of polyethyleneimine, 20.8 to 23.8% by weight of film-forming agent, 0.8 to 3.6% by weight of liquid acrylate, 0 to 1.0% by weight of pyrogenic silica, 8.0 to 12.0% by weight of pigment, 0.0 to 1.0% by weight of pigment disperser and water as remainder.

8. A method of improving the early resistance to driving rain of physically curing coating compositions based on aqueous acrylate dispersions, which are adjusted to an alkaline pH with ammonium hydroxide or an aminoalcohol, which is readily volatile at ambient temperature, comprising the steps of providing an additive characterized by an aqueous dispersion, containing a polyethyleneimine with a number average molecular weight in the range from 50,000 to 3,000,000, at least one representative of the group comprising 1,3-dihydroxy-2,2,4-trimethylpentane and esters thereof, butyl diglycol acetate and methoxypropanol as film-forming agents and at least one representative of the group comprising the liquid acrylates and pyrogenic silica as thickening agent, as well as optionally a pigment and optionally an ammonium acrylate as pigment disperser;

and incorporating 1.0 to 5.0% by weight of the additive in a coating composition.

9. The method of claim 8, wherein 2.0 to 3.0% by weight of the additive is incorporated in the coating composition.

10. The method of claim 8, characterized in that the additive is incorporated into a conventional commercial fire protection coating composition, which contains an aqueous acrylate latex as well as defoamers, plasticizers, preservatives, fillers, extenders, wetting agents, dispersants and thickeners as conventional ancillary materials and is adjusted with ammonium hydroxide or aminoethanol to a pH in the range from 8.0 to 9.0.

11. The method of claim 10, characterized in that the additive is adjusted with ammonium hydroxide or aminoethanol to a pH of 8.5.