Stain and soil repellent composition

Abstract: The invention relates to a stain and soil repellent composition for a carpet, especially from polyamide, wherein a first condensation product of hydroxyaromatic compounds and formaldehyde, which is free of sulphonic acid- and carboxyl-groups; and a second condensation product of hydroxyaromatic compounds and formaldehyde, which is at least partially sulphonated is applied to the carpet in a foam application process together with a fluorocarbon compound. (end of abstract)

Stain and soil repellent composition description/claims

Brief Patent Description

Full Patent Description

Patent Application Claims

BACKGROUND OF THE INVENTION

The present invention relates to a stain and soil repellent composition for carpets. The invention especially relates to a stain and soil repellent composition for carpets made from polyamide, wool and their mixtures.

During the production of carpets, various stain and soil repellent chemicals are often applied. The application is typically carried out in two steps with the application of the stain repellent being first, followed by a treatment with a fluorocarbon compound.

A stain repellent can be applied to a carpet in a continuous or discontinuous process, in which between 3 and 7 weight-% of the stain repellent relative to the pile weight (the weight of the utilized fiber) is used. It is also known that considerably higher concentrations, for example up to 10 weight %, can be utilized.

In the discontinuous application, a separate treatment bath is utilized after the dyeing step, in which the stain repellent is applied to the carpet at a pH between 2.5 and 7.

In the continuous application, the stain repellent is applied to the carpet with suitable devices, such as a waterfall applicator, immersion tank and Fluidyer® apparatus.

After the application of the stain repellent, a treatment with a fluorocarbon compound follows as the last finishing step, for example with a desired concentration of from 1.0 to 1.6 weight-% of fluorocarbon relative to the pile weight of the carpet. The application of the fluorocarbon compound typically precedes the dryer of the continuous dye unit or is prior to the coating oven. The simplest procedure is a spray application which is carried out with a suitable spray device. The fluorocarbon compound is applied as an aqueous solution to a dry or lightly moistened carpet. The most often-used application method is a foam application. With this system, a highly concentrated solution of the fluorocarbon compound can be applied to the carpet as a foam with minimal wetness. For the foam creation, special foaming aids are added to the fluorocarbon compounds, which then degrade at the selected drying temperatures, and the fluorocarbon compound remains on the fiber and bonds to it.

The two-step process is time consuming, relatively high cost, and resource intensive. Thus, the application of the stain repellent together with the fluorocarbon in a single step is advocated.

For example US2003/0204015 A1 reveals that a mixture containing a sulphonated condensation product of phenol and formaldehyde and other compounds as stain repellent, and fluorocarbon compounds can be applied to the fibers.

The application of stain repellent based on resole together with fluorinated, oil, water and/or soil repellent substances on a polyamide substrate is disclosed in U.S. Pat. No. 5,447,755.

However, there is still a need for improved stain and soil repellent compositions for one-step application. Therefore, the task of the present invention is to provide an improved stain and soil repellent composition compared to the current state of technology.

This task was achieved according to the invention by using a combination of two different stain repellents together with a fluorocarbon compound to impart desirable stain and soil repellent properties to carpets.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is a stain and soil repellent composition which encompasses the following components:

- (a) a first condensation product of hydroxyaromatic compounds with formaldehyde, which is free of sulphonic acid and carboxylic groups,
- (b) a second condensation product of hydroxyaromatic compounds with formaldehyde, which is at least partially sulphonated,
- (c) at least one fluorocarbon compound,
- (d) at least one foaming agent, in case that (c) has no foam building properties,