DE1619262A1 - Coating agents - Google Patents

Description

International latex & 25.10.67

Chemical Corporation DrMl / HWi

Dover, Delaware

Hau3 Uo. 5436

Coating agents

Scope of the invention iä; an agent for the coating or reverse consolidation of woven or knitted fabrics. In particular, "the invention relates to coating compositions for the rear consolidation of carpets which / are produced, for example, according to the Axminster and Wilton processes.

It is known to use hardening finishes or coatings on the back of upholstery fabrics and woven carpets to apply to increased stiffness, fuller grip, increased weight, improved! Toppenveraiikerung, improved resistance against fraying of cut edges. (Cut resistance), improved dimensional stability, anti-slip properties, improved abrasion resistance, etc. @u obtained, usually so far, starch and casein have been used for this Zw © ok, while more recently polyvinyl acetate emulsionsa have been used became.

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Furthermore, latices of butadiene / styrene copolymers with about 10-15 percent by weight butadiene "known heretofore only "limited applicability as a stiffening agent or Have found reinforcing polymers in mixtures with film-forming rubber-elastic polymer latices. For example high styrene-containing polymer latices are used to reinforce natural or synthetic rubber latex in the Used in making foam rubber.

There are also carboxylated butadiene-styrene copolymers known to not bind in the form of an aqueous latex corrugated fibers are used (DAS 1,191,683). According to another known proposal, they are in emulsion form applied carboxylated butadiene-styrene copolymers used as an air-drying coating agent (DAS 1.221.748).

It has now been found that certain latex polymers of butadiene, Styrene and unsaturated carboxylic acids have particularly valuable properties for the rear consolidation of substances, especially of woven carpets. These polymers contain a styrene content that is far higher than that previously known carboxylated butadiene-styrene latioes. from conventional polymers are known to have been developed with the flexibility of high-quality thin films in mind, To fully utilize its properties as a binder for filler © and F & i§ @ rn to unfold. In contrast, according to the invention Polished polymers are relatively stiff and at room temperature Not flexible and even to a certain extent broody at the time

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- .- -5- ■ "" -. "- \ ν ■■ · ■ The invention therefore precedes a Besciiiclitüngsmiijtel for woven or knitted fabrics, in particular for the backs of carpets based on aqueous emulsions- of acid groups-containing butadiene-styrene copolymers, characterized by efajKK, optionally containing further additives from copolymer

5-30 parts by weight butadiene, ■ ■. , ■ 95-10 "styrene,

0.2-7 it unsaturated * carboxylic acid.

Examples of those which can be used according to the invention as comonomers Carboxylic acids in the polymers are acrylic acid, methacrylic acid, fumaric acid, itaconic acid and the monoesters of fumaric acid and Itaconic acid.

Other unsaturated carboxylic acids are also suitable.

In addition to the three essential Go monomers mentioned the polymers can be ethylenic even smaller amounts of others Contain unsaturated co-monomers.

TJm the full effectiveness of the coating composition according to the invention should be the weighted average particle diameter of the polymer particle has a value of 0.22 / u do not exceed. It is preferably 0.1-0.2 / u. Of the weighted average particle diameter of a latex can easily determined by known methods, e.g.

009885/1992

Electron microscopy or light scattering (Heller, J.öhem.Phys. 2J5 3.S.498). The weighted average Particle diameter is expressed mathematically as

d =

Mean therein

d = s weighted average particle

. diameter

n ^ = number of particles.

in a subgroup that

all have a durometer of d * / U.

The polymers to be used according to the invention are in Form of a thin film, relatively hard and stiff. The latices are not or barely film-forming at room temperatures able to form a coherent film when drying thin layers at room temperature.

Subsequent to the back ^ coating of the fabrics or Carpets will dry faster at elevated temperatures above the sintering temperature (G-load temperature) made of the polymers mentioned. However, it has been found that latices with smaller particles are faster and at form a coherent layer at lower temperatures than latices, which have a particle diameter greater than own about 0.22yu. As a result, there is stiffening at lower temperatures or at increased endurance speeds of the fabric ensured by the drying system.

009885/199 2 _8A p

The latices of the copolymers are applied to woven or knitted fabrics in the form of thin coatings, in the case of carpets preferably with a dry weight of the coating of 135-680 g / m, and in the case of fabrics such as upholstery fabrics a dry weight of the coating of 17-270 g / m. This can be done by known methods, for example using a doctor blade, a flat roller or by spraying. The drying is preferably carried out at an elevated temperature in order to increase the throughput. It can be completed in the usual way, for example using suction devices, drying ovens or under infrared lamps. The latex is normally used with a polymer solids content of approximately 40 to 60 %, preferably 40 to 50%.

On the other hand, thickeners, for example of the polyaorylate type, can also be added to control the weight of the coating. On the other hand, if rapid penetration of the latex into the fabric is desired, for example through the back of the carpet to the base of the carpet yarns, it is convenient to dilute the latex to a relatively low level of contaminants, for example about $ 20, prior to use. with or without the addition of a fermentation agent.

Apart from the additives mentioned, small amounts of mineral fillers can also be added to the latex before it is applied, such as oleoium carbonate or barite.

; volume

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0 0 9 8 8 5/199 2

MB Q «Μ

Bs is convenient, no more than about 100 parts by weight of the mineral filler to 100 parts by weight of latex solid to use. In general, however, it is advantageous to use no or as little filler as possible, to all the advantages of the coating agent according to the invention bring about. However, economic considerations sometimes allow the use of an inexpensive diluent require, although this leads to a deterioration in the properties of the coated fabric.

Finally, others can also be used in fabric coating mixtures Usual additives to the latices are used, for example antioxidants, stabilizers, thickeners, Bases such as ammonia, bactericides and similar substances.

The use of vulcanizing agents in the mixtures according to the invention is not necessary, since the drying process is generally sufficient to crosslink the latioes. W The crosslinking takes place the Pasersubstrate of the substance by intermolecular Wasserstoffbrüokenbindung on the free carboxyl groups and Wasserstoffbrüokenbindung the carboxyl groups with polar groups. A short heat treatment, for example at 130-140 ° C, may be desirable in some cases after drying, e.g. to achieve optimal values for the top anchorage, but it is not absolutely necessary. . '

The inventive beeohiolrfeungBmittel enables in

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easier and. economical way to produce coated or backed fabrics with improved stiffness and fuller grip, in particular of carpets. However, it is also the case in many areas. Coating of other types of woven or knitted Substances applicable.

The carboxylated polymers with a high styrene content used as coating agents according to the invention have advantages over the non-carboxylated types with regard to i

improved heat aging properties, improved processing properties, e.g. mechanical stability under. Conditions of use, improvement of the upright anchorage and the cut resistance, improved film formation, which is evident in faster drying and stronger and harder coatings. Furthermore, they have an improved abrasion resistance compared to non-carboxylated high styrene polymer coatings, furthermore improved adhesion and affinity to fibers due to the increased polarity of the polymer, furthermore improved washability. This is r ^"J surprising that latexes normally not in flexible and fragile films, in the present invention coating compositions of have a big usability. It is achieved an excellent reinforcing effect, which is accompanied by the other aforementioned improvements without the the carpet covers tend to show cracks or wrinkles when folded or bent

009885/1992

Ability is based on the easy penetration of the carboxylated latex through the back of the carpet into the pile yarns. Farther

becomes the stiffening effect of the coating with a thank you dampening of the fabric or carpet / hydrophobic nature of the polymer and its good adhesive properties on fabrics and yarns are maintained.

The invention is explained using the following example :

A latex made of butadiene / styrene / fumaric acid copolymer, in the manufacture of which the proportion by weight of the individual monomers was 25/73/2 based on 100 parts by weight of all monomers and whose weighted average particle diameter was 0.12, was diluted to a solids content of $ 20. A polyacrylate type thickener was added to provide a viscosity suitable for flat roll application to adjust. An "Axminster Woven Carpet" was made using Flat roll coated back so that the dry weight

the polymer application was 135 g / m 2. The coated carpet ran through at a speed of 9.1 cm / sec. a furnace at a temperature of 120-130 ⁰ C. The carpet had when leaving the furnace have a moisture content of 14 ^ 5. The back application was well connected and the Joppen anchoring and the stiffening effect were excellent. In contrast, a similar polymer latex with a weighted average partial ohmic diameter of 0.28 yu, which was diluted to the same solids content and thickened in the same way, did not show any combined

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hanging coating under the conditions described above. The speed of passage of the Deppich through an oven
had to be 7> 6 cm / sec. and the moisture content of the carpet to be reduced to 8 i "* to a uniform IToppenverankerung, G-ESCH loss standardized to obtain the film, and stiffness properties.

Claims
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00 9885/1992

Claims (2)

ντογ.Ήο. 5436 1619762 claims 1) Coating agents for woven or knitted fabrics, especially for the back of carpets, based on aqueous emulsions of butadiene-styrene copolymers containing acid groups, characterized by one, optionally containing further additives. Oopolymer from 5 - 30 parts by weight butadiene, 95 - 70 "styrene, 0.2 - 7 "unsaturated. Carboxylic acid. 2) Coating agent according to claim 1, characterized in that polymer parts have a weighted average leilchendurohmesser d of not more than 0.22 al, preferably 0.1-0.2 u and where "d" is defined as ^ te TTl · CL · Line ii and where n _± denotes the number of all parts of a subgroup which have a partial ohmic diameter of n ^ ₁ Ai . 009 885/19 92