EP0040335A2 - Sizing agent and process for its manufacture - Google Patents

Abstract

A sizing agent for yarns made of cotton, regenerated cellulose and synthetic fibers and their mixture. The sizing agent substantially comprises a hydroxyalkylated polysaccharide from the seed of Cassia occidentalis. The polysaccharide has a viscosity of from 40 to 10,000 mPas (10% aqueous solution, 80 DEG C., Brookfield RVT) and a substitution degree of from 0.05 to 1.0.

Description

Before weaving, warp yarns are provided with solutions, melts, dispersions or emulsions of sizing agents which impart smoothness, consistency, suppleness and strength to the yarn, so that processing on the loom is improved. After weaving, the sizing agent is removed in most cases.

It is known to use native or modified starches, cellulose ethers such as carboxymethyl celluloses, protein products, polyvinyl alcohols, polyacrylates and others as sizing bases. Cotton and rayon wool are mainly treated with sizes based on natural materials, in the case of mixed spun fabrics and synthetic yarns, the majority of sizes are sized with semi-synthetic or fully synthetic products, also in combination with the natural materials mentioned.

• a) Schlichten, die sich nur nach Einwirkung von Enzymen oder Chemikalien durch anschließendes Auswaschen mit Wasser entfernen lassen,
• b) Schlichten, die durch einfaches Auswaschen mit Wasser entfernbar sind.

After being removable from the fiber, a distinction is made between two groups of sizing agents:

• a) Sizes that can only be removed after exposure to enzymes or chemicals by subsequent washing with water,
• b) Finishes that can be removed by simply washing them out with water.

With increasing rationalization, the last group of water-washable bulk agents is becoming increasingly important. Substituted starches, carboxymethyl cellulose, polyvinyl alcohol and polyacrylates are used in particular. From the point of view of easy removability from the tissue, these products are included. advantage used. Almost without exception, however, these semi-synthetic or fully synthetic sizing agents show only very poor biodegradability, which manifests itself in a low biological oxygen requirement, but in a correspondingly high chemical oxygen requirement.

Sizing agents based on naturally occurring polysaccharides, e.g. Starch sizing is characterized by good biodegradability, but it is not or only insufficiently suitable for sizing semi-or. fully synthetic fibers. They are therefore preferably used in mixtures with the agents mentioned.

It has also been attempted by varying the poly _'saccharide switch to other natural product sizing. The flour of Tamarindus Indica, the so-called tamarind seed flour, was also described as a sizing agent (Whistler Industrial Gums, 461 ff, Melliand, 1956, 588 ff). However, the use of such sizing agents is almost exclusively limited to the Indian subcontinent, since the disadvantages of tamarind seed sizing agents prevent further spread.

The invention now relates to a readily biodegradable, water-washable sizing agent, which is characterized by excellent adhesive strength and suppleness.

According to the invention it was found that the polysaccharide from the seed of Cassia Occidentalis after hydroxyalkylation and partial depolymerization is an excellent sizing agent for yarns made of cotton, regenerated cellulose and synthetic fibers, as well as their blends.

The invention thus relates to a sizing agent for yarns made of cotton, regenerated cellulose and synthetic fibers, and mixtures thereof, which consists essentially of a hydroxyalkylated polysaccharide from the seeds of Cassia Occidentalis, which has a viscosity of 40-10,000 mPas (10% aqueous solution , 80 ° C, Brookfield RVT) and has a degree of substitution of 0.05 - 1.0.

The sizing agents according to the invention have a viscosity range of 40-10,000 mPas, preferably 200-9,000 mPas, in aqueous solution with a dry substance content of 10%. The viscosity is measured at 80 ° C. on a Brookfield viscometer, model RVT, at 20 rpm.

The hydroxyalkylated polysaccharides used according to the invention as sizing agents have a degree of substitution of 0.05-1.0, preferably 0.1-0.9.

Hydroxyethylated and hydroxypropylated polysaccharide is preferred, although in principle hydroxyl-C _2-4 -alkylated polysaccharide can be used.

The polysaccharide from Cassia Occidentalis used according to the invention is predominantly a galactomannan.

The sizing agents according to the invention are prepared by hydroxyalkylating polysaccharide from the endosperms of Cassia Occidentalis with an alkylene oxide or haloalkanol in a known manner and before, during or after the hydroxyalkylation to achieve the desired viscosity in a manner known per se. The depolymerization can be carried out, for example, with hydrogen peroxide or with inorganic peroxides, or by hydrolysis or by means of enzymes.

In a preferred method, the polysaccharide from endosperms of Cassia Occidentalis is first kneaded briefly with aqueous NaOH solution in a kneader mixer, then an alkylene oxide, such as preferably ethylene oxide or propylene oxide, is added to the mixture, and several are added at a temperature of 40-80 ° C. Worked well for hours with the mixer closed. After the reaction has ended, the depolymerization is carried out with an aqueous hydrogen peroxide solution at elevated temperature, for example 50-90 ° C. This depolymerization can also be carried out before the hydroxyalkylation. The resulting, almost homogeneous paste can then e.g. be dried on a drum dryer. There is a product that is soluble in hot and cold water.

The sizing agent according to the invention is practically salt-free and, even in its molecular structure, is not a salt, e.g. the carboxymethylates or polyacrylates. As is well known, salt-free sizing agents protect the weaving tableware and cause no corrosion.

Compared to the salt-free starch sizes, the products according to the invention have the advantage of significantly better size effects. That is compared to the salt-free coatings based on CMC, PVA or acrylate The sizing agent according to the invention is readily biodegradable and easy to remove from the waste water in a biological sewage treatment plant. In contrast to polyvinyl alcohol, it is also readily soluble in an alkaline medium.

It therefore combines all the good properties of known sizing agents without having their disadvantages.

By using sizing agents according to the invention it is achieved that, due to the excellent elasticity and the good film-forming ability, the yarns sized with this have a good surface smoothness and thus have sufficient resistance to the heavy demands of the weaving process. This applies in particular to very dense tissue qualities.

Because the size can be easily removed from the fabric simply by washing with water, there are additional advantages for further processing. For example, time and costly enzymatic desizing.

The sizing agent according to the invention is readily biodegradable. The chemical oxygen demand of such a size solution drops to less than 20% of the initial value after 5 days of incubation with activated sludge. Comparisons with the commonly used water-washable sizing agents show that polyvinyl alcohol, polyacrylates and carboxymethyl cellulose are virtually non-degradable under these conditions.

The following examples illustrate the invention. All parts are parts by weight.

example 1

100 parts * Cassia Occidentalis endosperms become * polysaccharide. placed in a kneading mixer and mixed with a solution of 1 part of hydrochloric acid (approx. 32%) in 80 parts of water within 5 minutes while running from the mixer. With thorough mixing, the mixture is left to degrade for a further 60 minutes at approx. 60-80 ° C. Then a solution of 6.5 parts of sodium hydroxide in 50 parts water is added over 30 minutes and mixed for another 30 minutes at this temperature (60-80 ⁰ C). 15 parts of propylene oxide are then added to the mixture, and the mixer is then tightly sealed. After kneading for 3 hours at 60 ° C. (product temperature), the reaction time has ended. Now the excess propylene oxide is removed by vacuum and the reaction mixture is mixed with 5 parts of hydrogen peroxide (approx. 32%) in 500 parts of water and kneaded at 60-90 ° C. for about 90 minutes. The paste is then homogeneous and is dried in a thin layer using a drum dryer.

The scale-like product sizing agent is soluble in cold and hot water, the 10% aqueous solution shows a viscosity of approx. 7000 - 8500 mPas at 80 ° C. The sizing agent has a degree of substitution of 0.27.

Example 2

100 parts ^* endosperms from Cassia Occidentalis ^* polysaccharide are placed in a kneading mixer and mixed with a solution of 40 parts hydrogen peroxide (32%) in 60 parts water within approx. 5 minutes from the mixer. Allow to mature for a further 30 minutes with thorough mixing. A solution of 8 parts of sodium hydroxide in 50 parts of water is then added over the course of about 30 minutes and the mixture is stirred at 80 ° C. for a further 90 minutes. The excess hydrogen peroxide is destroyed with a solution of 8-12 parts of sodium sulfite in 60 parts of water within 30 minutes at 80 ° C. until H ₂ O _{2 is} detected negatively.

15 parts of propylene oxide are then added to the mixture, and the mixer is then tightly sealed. The reaction is complete after kneading for 3 hours at 60 ° C. (product temperature). Now the excess propylene oxide is removed with vacuum. The heavily swollen splits are mixed with 400 parts of water and for 60 minutes kneaded at 60-90 ° C. The light, almost homogeneous paste is dried in a thin layer on a drum dryer.

The scale-like sizing agent is cold and warm. water-soluble, its 10% aqueous solution shows a viscosity of approx. 1000 mPas at 80 ° C. The degree of substitution was determined to be 0.25 (iodine-hydrogen method).

Example 3

100 parts of Cassia Occidentalis endosperms are placed in a kneading mixer and a solution of 5 parts of sodium hydroxide in 100 parts of water is added with the mixer running for about 5 minutes. After kneading for 30 minutes, 45 parts of propylene oxide are added to the mixture and the mixer is closed. With thorough mixing, the reaction mixture is allowed to react at 60 ° C. (product temperature) for a further 3 hours. The excess propylene oxide is then removed in vacuo and 50 parts of hydrogen peroxide (32% strength) in 500 parts of water are added to the reaction mixture, and the mixture is kneaded at 60-90 ° C. for about 90 minutes. The almost homogeneous paste is dried in a thin layer on a drum dryer.

The scale-like sizing agent is soluble in cold and hot water, its 10% aqueous solution shows a viscosity of approx. 700 mPas at 80 ° C. The degree of substitution was determined to be 0.7 (iodine-hydrogen method).

Example 4

100 parts of flour from the endosperms of Cassia Occidentalis are placed in a kneading mixer and mixed with a solution of 5 parts of sodium hydroxide in 30 parts of absolute methanol within 5 minutes while the mixer is running. After kneading for 30 minutes, 10 parts of propylene oxide are added to the mixture and the mixer is closed. With thorough mixing, the reaction mixture is allowed to react at 60 ° C. (product temperature) for a further 3 hours. Now the methanol and the excess propylene oxide are removed and the reaction material mixed with 50 parts of hydrogen peroxide (32%) in 500 parts of water and kneaded at 60-90 ° C for about 30 minutes. The homogeneous paste is dried in a thin layer on a drum dryer. The scale-like sizing agent is soluble in cold and hot water. The 10% aqueous solution shows a viscosity of approx. 500 mPas at 80 ° C. The degree of substitution was determined to be 0.15.

Example 5

100 parts * endosperms from Cassia Occidentalis * polysacchar are placed in a kneader mixer and a solution of 5 parts sodium hydroxide in 100 parts water is added to the mixture over a period of about 5 minutes while the mixer is running. After kneading for 30 minutes, the mixture is mixed with 15 parts of ethylene oxide and the mixer sealed. With thorough mixing, the reaction mixture is allowed to react at 60 ° C. (product temperature) for a further 3 hours. Now the excess ethylene oxide is removed in vacuo and 50 parts of hydrogen peroxide (32%) in 500 parts of water are added to the reaction mixture and the mixture is kneaded at 60-90 ° C. for about 90 minutes. The homogeneous paste is brought to dryness on a drum dryer.

The scale-like sizing agent is soluble in cold and hot water. Its 10% aqueous solution shows a viscosity of approx. 800 mPas at 80 ° C. The degree of substitution was determined to be 0.3 (iodine-hydrogen method).

Example 6

100 parts of flour from the endosperms of Cassia Occidentalis are placed in a kneading mixer and mixed with a solution of 5 parts of sodium hydroxide in 30 parts of absolute methanol within 5 minutes while the mixer is running. After 30 minutes of kenting, the mixture is mixed with 15 parts of ethylene oxide and the mixer sealed. With thorough mixing, the reaction mixture is allowed to react at 60 ° C. (product temperature) for a further 3 hours. Now the excess ethylene oxide is removed (vacuum) and 50 parts of hydrogen peroxide (32% strength) in 50 parts of absolute methanol are added to the reaction mixture and the mixture is kneaded at 60-90 ° C. for about 90 minutes. After drying in a vacuum a cold and hot water soluble powdered sizing agent is obtained. The 10% aqueous solution of the sizing agent shows a viscosity of approx. 1? 00 mPas at 80 ° C. The degree of substitution was determined using 0.25 (iodine-hydrogen method).

Example 7

100 parts of endosperms from Cassia Occidentalis are placed in a kneading mixer and mixed with a solution of 10 parts of hydrochloric acid (32%) in 80 parts of water within 5 minutes while the mixer is running. With thorough mixing, it is left to degrade for a further 60 minutes at approx. 60-80 ° C. A solution of 10 parts of sodium hydroxide in 50 parts of water is then added over the course of about 30 minutes and the mixture is stirred at this temperature (60-80 ° C.) for a further 30 minutes. The strongly swollen but still free-flowing endosperms from Cassia Occidentalis are then mixed with 8 parts of propylene oxide and the mixer is then sealed. After kneading for 3 hours at 60 ° C., the reaction is complete. Now the excess propylene oxide is removed in vacuo and 35 parts of hydrogen peroxide (32% strength) in 35 parts of water are added to the reaction mixture, and the mixture is kneaded at about 50 ° C. for about 90 minutes. The strongly swollen, but still free-flowing sizing agent is ground in a mill with simultaneous drying. The 10% aqueous solution of the product shows a viscosity of approx. 200 mPas at 80 ° C. The degree of substitution was determined to be 0.1 (iodine-hydrogen method).

Example 8

100 parts of endosperms from Cassia Occidentalis are placed in a kneading mixer and mixed with a solution of 5 parts of sodium hydroxide in 100 parts of water within about 5 minutes with the mixer running. After kneading for 30 minutes, the mixture is mixed with 15 parts of ethylene oxide and the mixer is closed. With thorough mixing, the reaction mixture is allowed to react at 60 ° C. for a further 3 hours. Now the excess ethylene oxide is removed (vacuum) and 50 parts of hydrogen peroxide (32% strength) in 50 parts of water are added to the reaction mixture and the mixture is kneaded at 60-90 ° C. for about 90 minutes. The strongly swollen, but still free-flowing product is ground in a mill with simultaneous drying. The 10% aqueous solution of the sizing agent shows a viscosity of 600 mPas at 80 ° C. The degree of substitution was determined using 0.85 (iodine-hydrogen method).

Example 9

40 kg of a sizing agent according to Example 7 were prepared in a turbo cooker with 450 l of cold water and boiled. The following material was finished on a drum sizing machine. Nm 30/1 polyester / cotton in a mixing ratio of 50%: 50% raw white, 4 456 threads, intended for cord fabrics with the fabric setting 27 / 54-30/20. The temperature in the size trough was constant at 85 ° C. The chain was immersed once in the liquor and squeezed twice, a squeezing effect of 115% being achieved. The warp yarn was processed on Sulzer weaving machines, the weaving efficiency being 98.0%. 0.005 warp thread breaks were calculated for 1000 warp and 10,000 weft threads.

The comparison test with a size product made from soluble starch and CMC with a finishing line of 60 kg on a 500 l finished fleet produced a weaving efficiency of 95.6%.

Example 10

With 8 kg of sizing agent according to Example 1 and 0.5 kg of sizing grease, 350 l of the finished liquor were produced in a pressure cooker and the following warp material was thus sized. Nm 40/1 cellulose, 2 096 threads
The fabric setting consisted of chain
and weft each Nm 40/1 and 20 threads per cm. The warp yarn was sized on a drum sizing machine, the yarn being immersed twice in the layer trough and squeezed twice. The temperature of the wash liquor was 90 ° C. A squeezing effect of 124% was determined. The useful output in the weaving mill was 97.8% for the chains thus sized, which corresponded to 0.015 warp thread breaks calculated on 1000 warp and 10,000 weft threads.

A counter-test with a combination size consisting of carboxymethylated starch and polyacrylate and a size concentration of 9 kg on a 350 l finished fleet produced a weaving efficiency of 96.2%.

Example 11

• Nm 64/1 Polyester/Baumwolle , im Mischungsverhältnis 50 %:50 % mit 5 024 Fäden in der Gewebeeinstellung 34/25 - 64/64.

Als Schlichtemaschine stand eine Trommelschlichtmaschine mit 9 Trockenzylindern zur Verfügung. Die Flottentemperatur betrug 80°C. Das Kettgarn wurde zweimal in die Flotte getaucht und zweimal abgequetscht mit einem Abquetscheffekt von 129 %. In der Weberei wurde eine Nutzleistung von 97.1 % erreicht. Der Staubanfall sowohl im Trockenteilfeld der Sohlichtemaschine als auch in der Weberei war äusserst gering.In a pressure cooker, 450 l of the finished liquor were produced using 35 kg of sizing agent according to Example 2 and 1.5 kg of sizing grease. The following warp material was finished:

• Nm 64/1 polyester / cotton, in the mixing ratio 50%: 50% with 5 024 threads in the fabric setting 34/25 - 64/64.

A drum sizing machine with 9 drying cylinders was available as the sizing machine. The liquor temperature was 80 ° C. The warp yarn was immersed twice in the liquor and squeezed twice with a squeezing effect of 129%. A useful output of 97.1% was achieved in the weaving mill. The amount of dust accumulated in the dry subfield of the sunlight machine as well as in the weaving mill was extremely low.

In the counter-test with 45 kg of low-salt CMC on 450 1 of the finished liquor, a efficiency of 96.6% was determined in the weaving mill.

Example 12

With 25 kg of sizing agent according to Example 3 and 1.0 kg of sizing wax, 500 l of the finished liquor were prepared in the turbo cooker. The following warp material was finished on a drum finishing machine. Nm 10/1 polyacrylonitrile yarn 100% with 2400 threads and the
Fabric adjustment threads per cm 17/17
Yarn number Nm warp and Nm weft each 10/1 The liquor temperature in the size trough was 80 ° C. The warp yarn was immersed twice and squeezed twice, the liquor consumption was 124%, the warp was woven into curtain fabrics on jacquard weaving machines. The efficiency was 0.0 warp thread breaks calculated on 1000 warp and 10,000 3-weft days,

In the counter search, 25 kg of polyvinyl alcohol were used on 5001 finished fleets, a weaver use effect of 0.024 warp thread breaks calculated on 1000 warp and 10,000 thrust threads being determined.

Example 13

A warp material Nm 16/1 cellulose 100% with 2 060 threads,
Fabric setting 17/14 threads per cm,
Yarn number chain Nm 16/1, weft Nm 16/1
was finished with a size liquor of 6 kg size according to Example 6 and 0.5 kg size grease on 500 liters of finished liquor on a drum size machine. The liquor temperature was a constant 85 ° C in the size trough. The warp yarn was dipped once in the liquor and squeezed twice with a squeezing effect of 131%. The warp yarn was dried to 6.5% residual moisture. The machine speed was 65 m / min. In the weaving mill, with the chain sized in this way, an efficiency of 95.2% was achieved with extremely low dust accumulation, corresponding to 0.018 warp thread breaks on 1000 warp and 10,000 weft threads.

The counter-test was carried out with 25 kg of medium-viscosity polyvinyl alcohol on 500 l of the finished liquor, a weaving efficiency of 95.3% being achieved.

Example 1 ₄

450 l of the finished liquor were prepared in a turbo cooker with 35 kg of sizing agent according to Example 5 and 0.5 kg of sizing fat. The following warp material was finished: Nm 70/1 cotton, intended for ticking fabric,
with 6580 threads in the fabric setting 47 / 42-70 / 70 As a sizing machine, a drum sizing machine with 9 drying cylinders and 2 sizing troughs was available. The liquor temperature during finishing was 80-85 ° C. The warp yarn was immersed twice in the liquor and squeezed twice with a squeezing effect of 134%. A useful output of 97.8% was achieved in the weaving mill, corresponding to 0.01 warp thread breaks on 1000 warp and 10,000 weft threads.

In the counter-test with 35 kg of low-salt CMC on 450 l of finished liquor, 96.2% efficiency was determined in the weaving mill.

Claims (11)

1. sizing agent for yarns made of cotton, regenerated cellulose and synthetic fibers and mixtures thereof, characterized in that it essentially consists of a hydroxyalkylated polysaccharide from the seeds of Cassia Occidentalis, which has a viscosity of 40-10,000 mPas (10% aqueous solution, 80 ° C, Brookfield RVT) and has a degree of substitution of 0.05 - 1.0. 2. Sizing agent according to claim 1, characterized in that the hydroxyalkylated polysaccharide is a hydroxyethylated or hydroxypropylated polysaccharide. 3. sizing agent according to claim 1 or 2, characterized in that the hydroxyalkylated polysaccharide has a viscosity of 200 - 9 000 mPas (10% aqueous solution, 80 ° .C, Brookfield RVT). 4. sizing agent according to one of the preceding claims, characterized in that the hydroxyalkylated polysaccharide has a degree of substitution of 0.1-0.9. 5. A process for the preparation of a sizing agent according to any one of claims 1-4, characterized in that polysaccharide from the endosperms of Cassia Occidentalis is hydroxyalkylated with an alkylene oxide in a manner known per se and before, during or after the hydroxyalkylation to achieve the desired viscosity in depolymerized in a manner known per se. 6. The method according to claim 5, characterized in that one carries out the depolymerization with hydrogen peroxide. 7. The method according to claim 5, characterized in that one carries out the depolymerization with inorganic peroxides. 8. The method according to claim 5, characterized in that the depolymerization is brought about by hydrolysis. 9. The method according to claim 5, characterized in that one carries out the depolymerization with enzymes. 10. Use of a hydroxyalkylated polysaccharide from the seeds of Cassia Occidentalis, which has a viscosity of 40 - 10,000 mPas (in 10% aqueous solution at 80 ° C, Brookfield RVT) and a degree of substitution of _' 0.05 - 1.0, for the sizing of Yarns made of cotton, regenerated cellulose and synthetic fibers, and their blends. 11. Use of a sizing agent according to claim 1 in combination with customary sizing agents such as starch and their derivatives, PVA, CMC, acrylate and customary sizing additives such as fats, glues and waxes for sizing yarns from cotton, regenerated cellulose and synthetic fibers, and mixtures thereof.