PRODUCTS PRESERVED WITH 5-CHLORO-2-METHYL-4-ISOTHIAZOLIN-3-ONE

Abstract

The invention relates to preserved products which contain 1 to 100 ppm of 5-chloro-2-methyl-4-isothiazolin-3-one with a content of 2-methyl-4-isothiazolin-3-one in the range from 0 to 2 wt. % based on the total amount of 5-chloro-2-methyl-4-isothiazolin-3-one, and to the use of 5-chloro-2-methyl-4-isothiazolin-3-one with a content of 2-methyl-4-isothiazolin-3-one in the range from 0 to 2 wt. % based on the total amount of 5-chloro-2-methyl-4-isothiazolin-3-one, for the preservation of products.

Claims

1. A product selected from the group consisting of paints, interior paints, varnishes, stains, renders, plasters, emulsions, latices, polymer dispersions, lignosulfonates, chalk suspensions, mineral slurries, ceramic masses, adhesives, sealants, products containing casein, products containing starch, bitumen emulsions, surfactant solutions, fuels, cleaning products, pigment pastes and pigment dispersions, liquid inks, lithographic liquids, thickeners, cosmetic products, toilet articles, water circuits, liquids in paper processing, liquids in leather production, liquids in textile production, drilling and cutting oils, hydraulic fluids, and cooling lubricants, comprising 1 to 100 ppm of 5-chloro-2-methyl-4-isothiazolin-3-one having a 2-methyl-4-isothiazolin-3-one content in the range from 0 to 2 wt %, based on the total fraction of the 5-chloro-2-methyl-4-isothiazolin-3-one.

2. The product as claimed in claim 1, characterized in that the product is selected from the group consisting of interior paints, plasters, polymer dispersions, and cosmetic products.

3. The product as claimed in claim 1, characterized in that the product contains less than 1.0 ppm of 2-methyl-4-isothiazolin-3-one.

4. The product as claimed in any of claim 1, characterized in that the product is a water-based product.

5. A polymer emulsion as defined in claim 1 comprising 5 to 100 ppm of 5-chloro-2-methyl-4-isothiazolin-3-one having a 2-methyl-4-isothiazolin-3-one content in the range from 0 to 2 wt %, based on the total fraction of the 5-chloro-2-methyl-4-isothiazolin-3-one.

6. The use of a polymer emulsion as claimed in claim 5 for producing paints and renders.

7. The use of 5-chloro-2-methyl-4-isothiazolin-3-one having a 2-methyl-4-isothiazolin-3-one content in the range from 0 to 2 wt %, based on the total fraction of the 5-chloro-2-methyl-4-isothiazolin-3-one as defined in claim 1, for reducing microbial infestation of a product, characterized in that the product is selected from the group consisting of paints, interior paints, varnishes, stains, renders, plasters, emulsions, latices, polymer dispersions, lignosulfonates, chalk suspensions, mineral slurries, ceramic masses, adhesives, sealants, products containing casein, products containing starch, bitumen emulsions, surfactant solutions, fuels, cleaning products, pigment pastes and pigment dispersions, liquid inks, lithographic liquids, thickeners, cosmetic products, toilet articles, water circuits, liquids in paper processing, liquids in leather production, liquids in textile production, drilling and cutting oils, hydraulic fluids, and cooling lubricants.

8. The use of a biocide composition having a pH in the range from pH 1 to pH 5, comprising: a) from 0.25 to 20 wt % of chloro-2-methyl-4-isothiazolin-3-one having a 2-methyl-4-isothiazolin-3-one content in the range from 0 to 2 wt % as defined in claim 1, based on the total fraction of the 5-chloro-2-methyl-4-isothiazolin-3-one, and b) a solvent, for reducing microbial infestation of a product, characterized in that the product is selected from the group consisting of paints, interior paints, varnishes, stains, renders, plasters, emulsions, latices, polymer dispersions, lignosulfonates, chalk suspensions, mineral slurries, ceramic masses, adhesives, sealants, products containing casein, products containing starch, bitumen emulsions, surfactant solutions, fuels, cleaning products, pigment pastes and pigment dispersions, liquid inks, lithographic liquids, thickeners, cosmetic products, toilet articles, water circuits, liquids in paper processing, liquids in leather production, liquids in textile production, drilling and cutting oils, hydraulic fluids, and cooling lubricants.

9. A process for reducing microbial infestation of a product, comprising the steps of: (A) providing a product having a 2-methyl-4-isothiazolin-3-one content in the range from 0 to 1 ppm, and (B) adding 1 to 100 ppm of 5-chloro-2-methyl-4-isothiazolin-3-one having a 2-methyl-4-isothiazolin-3-one content in the range from 0 to 2 wt % as defined in claim 1, based on the total fraction of the 5-chloro-2-methyl-4-isothiazolin-3-one.

10. The process as claimed in claim 9, characterized in that in a further process step, process step, process step (C), the 5-chloro-2-methyl-4-isothiazolin-3-one is decomposed by means of at least one 5-chloro-2-methyl-4-isothiazolone-decomposing compound.

11. The process as claimed in claim 9, characterized in that in a further process step, process step (D), at least one further biocide is added.

12. The process as claimed in claim 9, characterized in that the product is selected from the group consisting of paints, interior paints, varnishes, stains, renders, plasters, emulsions, latices, polymer dispersions, lignosulfonates, chalk suspensions, mineral slurries, ceramic masses, adhesives, sealants, products containing casein, products containing starch, bitumen emulsions, surfactant solutions, fuels, cleaning products, pigment pastes and pigment dispersions, liquid inks, lithographic liquids, thickeners, cosmetic products, toilet articles, water circuits, liquids in paper processing, liquids in leather production, liquids in textile production, drilling and cutting oils, hydraulic fluids, and cooling lubricants.

13. The process as claimed in claim 10, characterized in that in process step (C) a compound is used which is selected from the group consisting of cysteine, mercaptoethanol, mercaptopropionic acid, methyl mercaptopropionate, glutathione, thioglycolate, sodium thiosulfate, sodium bisulfate, pyrithione, mercaptopyridine, dithiothreitol, mercaptoethanesulfonate, and sodium formaldehyde sulfoxylate.

14. The process as claimed in claim 11, characterized in that the biocide added in process step (D) is selected from the group consisting of 1,2-benzisothiazolin-3-one, 2-bromo-2-nitropropane-1,3-diol, zinc 2-mercaptopyridine N-oxide, a silver source, a zinc source, and 2,2-dibromo-3-nitrilopropionamide, or a mixture of two or more.

Description

The Present Invention is Described in More Detail Using the Example Set Out Below:

[0079] Added to a preservative-free styrene-acrylate dispersion were 20 ppm of 5-chloro-2-methylisothiazolin-3-one, having a 2-methylisothiazolin-3-one content of <1 wt %. The styrene-acrylate dispersion thus preserved was then used for producing a water-based emulsion paint. The composition of the paint produced was as follows: 25.7 wt % water

0.2 wt % acrylate-based wetting and dispersing agent
0.2 wt % mineral oil-based defoamer
2.0 wt % water softener (sodium polyphosphate)
0.2 wt % ammonia
4.0 wt % titanium oxide (pigment)
51.0 wt % calcium carbonate (filler)
5.0 wt % talc (filler)
0.4 wt %% cellulose ether
2.0 wt % organic solvent for lowering the minimum film-forming temperature
9.0 wt % the styrene-acrylate dispersion preserved with 20 ppm of 5-chloro-2-methylisothiazolin-3-one
20 ppm 5-chloro-2-methylisothiazolin-3-one, having a 2-methylisothiazolin-3-one content of <1 wt %

[0080] By means of microbiological investigations, no microbial growth was found in the emulsion paint, whereas microbial growth was detectable in individual components. The highly active 5-chloro-2-methylisothiazolin-3-one was therefore sufficient to cause complete killing of the microorganisms introduced via the individual components of the paint.

[0081] In order, from the emulsion paint, which contained significant quantities of 5-chloro-2-methylisothiazolin-3-one, to produce a paint unobjectionable for allergics in relation to 5-chloro-2-methylisothiazolin-3-one and 2-methylisothiazolin-3-one present therein, to produce, these isothiazolin-3-ones were decomposed by addition of 50 ppm of cysteine, based on the emulsion paint. After just 3 hours, 5-chloro-2-methylisothiazolin-3-one was no longer detectable in the emulsion paint by HPLC.

[0082] The paint thus produced was now free from microorganisms, through the use of the effective broad-spectrum biocide 5-chloro-2-methylisothiazolin-3-one, but as a consequence of the decomposition of the biocide by the cysteine, it was susceptible to newly introduced microorganisms which may enter the paint in the course of storage.

[0083] In order to protect the paint against such microbial infestation during storage, therefore, 50 ppm of 1,2-benzisothiazolin-3-one, 100 ppm of zinc 2-mercaptopyridine N-oxide (zinc pyrithione) and 10 ppm of zinc oxide were added, based on the emulsion paint, for ongoing preservation. The paint thus produced had a storage stability of at least 6 months.