JPS6128559A - Production of dried water-soluble dye - Google Patents

Abstract

PURPOSE:To obtain a dried water-soluble dye which neither causes deterioration in dyeing characteristics nor forms fine particles, by incorporating modified starch and a surfactant in an aq. paste of a water-soluble bye and spray-drying it. CONSTITUTION:Modified starch and a surfactant are incorporated in an aq. paste of a water-soluble dye in such a quantity that each of them accounts for 0.1-20wt% of the quantity of the final dry product. The paste is then spray- dried. Examples of the water-soluble dyes are sulfo group-contg. dyes such as direct dyes, acid dyes, reactive dyes and fluorescent dyes, cationic group-contg. dyes such as cationic dyes and weakly basic dyes. Examples of the modified starch are cyanoethylated starch, carboxymethylated starch, acetylated starch and oxidized starch. Preferred examples of the surfactants are anionic and nonionic surfactants.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for spray drying a water-soluble dye paste to obtain a dry product of a water-soluble dye.

PRIOR ART It is known to spray dry aqueous pastes of water-soluble dyes to obtain granular dry dyes. However, the granular dry dye obtained in this way often contains a large amount of fine particles, so when handling it, dust is likely to be generated, which is very troublesome in can collection work, dyeing work, etc. This is often a problem. A common method for solving this problem is to add additives such as liquid paraffin, dodecylbenzene, and other poorly soluble chemicals to the dye paste and then dry the dye paste. However, in this method, since the additives mentioned above are difficult to dissolve in water, they not only float up on the dyeing solution as oil during dyeing and have a negative effect on the dyeing results, but also these additives are in the form of granules obtained by spray drying. In order to reduce the fluidity of dry dyes, spray drying, which has been in high demand in recent years with the spread of automatic dyeing machines, tends to break down the granules of dry dyes, and only dry products can be obtained that tend to generate dust.

``Problem to be Solved by the Invention'' To generate fine particles that cause dust generation without impairing the dyeing properties in a method for producing a granular dry product by spray drying a water-soluble dye paste. It is desired to develop a manufacturing method that is free of this. ``Means for Solving the Problems'' As a result of our earnest efforts to solve the problems in the production of dried water-soluble dye products as described above, we have arrived at the present invention. That is, in the present invention, modified starch and a surfactant are added to an aqueous paste of a water-soluble dye so that the content in the dry product is 0.1 to 20 percent (by weight), and then spray-dried to form a granular water-soluble dye. The purpose is to manufacture dried dye products.

In the method of the present invention, water-soluble dyes are dyes having a sulfonic acid group such as direct dyes, acid dyes, reactive dyes, and fluorescent dyes, or dyes having a cationic group such as old basic dyes and cationic dyes.

Examples of the processed starch used in the method of the present invention include cyanoethylated starch, carboxymethylated starch, phosphorylated starch, acetylated starch, and oxidized starch.

Furthermore, as the surfactant used in the present invention, anionic and nonionic surfactants are preferable, such as genin sulfonic acid salts, condensates of alkylnaphthalene 4-sulfonic acids and formaldehyde,
Condensates of naphthalene sulfonic acids and formaldehyde, alkylbenzenesulfonic acids, higher alcohol sulfuric esters, alkali metal salts of acrylic acid polymers, etc.
Examples of nonionic surfactants include polyoxyethylene alkyl ethers, polyoxyethylene alkylphenol ethers, sorbitan fatty acid esters, and polyoxyethylene fatty acid esters.

These modified starch and surfactant are each contained in the water-soluble dye dry product in a range of 0.1 to 20 cents (by weight), more preferably in a range of 2 to 10 percent (by weight) each. Water-soluble dyes are added to the aqueous paste before spray drying. At this time, it is desirable that the total content of the processed starch and the wing surface active agent be 30% (by weight) or less.

The spray temperature of a spray dryer is usually 130-200℃.
(Inlet hot air temperature). In addition to processed starch and surfactants, the dried water-soluble dye may contain bilges such as common salt, sodium chloride, and phosphate, which are usually added to water-soluble dyes.

The water-soluble dye dried product obtained by the drying method of the present invention is in the form of granules, but whether or not a large amount of fine particles that cause dust are produced is determined by measuring the spatula angle of the dried product. Usually, the spatula angle is 400. If it is below, it can be said that it is a good dried product with less dust generation.

The quality of the fluidity is also judged by the spatula angle. If the spatula angle is 40' or less, the fluidity of the dried product is good and automatic weighing is not a problem (it can be carried out).

"Example" The present invention will be explained in more detail by way of Examples.

In the examples, "parts" mean parts by weight.

Example 1゜(Contains 45% moisture) Par 7 Ectoamyl A-59
After adding 2.7 parts of 14 (cyanoethylated starch, manufactured by Abehe) and 5.5 parts of thymol N (condensate of naphthalene sulfonic acid and formali, manufactured by Kao Soap), 60 parts of water was added and stirred. It was made into an aqueous slurry liquid. This product was spray dried at an inlet hot air temperature of 180°C and an outlet hot air temperature of 100°C to obtain 55 parts of a granular dry product. It contained 8.7% (by weight) of cyanoethylated starch and 4.3% (by weight) of a condensate of naphthalene sulfonic acid and formalin (thymol N). The particle size of this dried product was 0.1% smaller than 200 mesh, and the spatula angle was 25°. This material had sufficient dust resistance and fluidity. Since the fluidity was excellent, the suitability for automatic measurement was also good.

Example 2 In the same manner as in Example 1, 100 parts of C, I Direct Yellow 86 p, c (containing 40% water), 3 parts of Par 7 Ectoamyl A3914, nonionic activator Emanone 3199 (manufactured by Kao Soap) were added. 6 parts and water were added to prepare an aqueous slurry with a concentration of 30 parts, and spray-dried under the same conditions as in Example 1 to obtain 62 parts of a granular dry product. This product contains 4.3% (by weight) Burfect Amyl A3914.
It contained 8.2% (by weight) of Emanone 3199. This product contained almost no particles smaller than s00 mesh, and the spatula angle was 28°.

The dried cat product had sufficient dust resistance and fluidity.

Examples 3 to 20 Aqueous slurries were prepared using various modified starches and surfactants using water-soluble dyes, and spray-dried according to the method of Example 1 to obtain dried granular water-soluble dye products. The following table shows the type and content of the water-soluble dye, modified starch and surfactant used and the content in the dried product, as well as the results of physical property tests of the obtained dried product.

(Note 1) Processed starch A: Par7 Ectoamyl A3914 (cyanoethylated starch, manufactured by Abebe) B: Peval MS-65 (carboxymethyl starch, manufactured by 8 Starch Chemical) C: Lastagen FO (oxidized starch, 8 Starch) Chemical) D: Purinomine
(Phosphated starch, manufactured by 8 Starch Chemical) (Note 2) Surfactant Demol BP: Surfactant whose main component is high-molecular polycarboxylic acid (manufactured by Kao Soap) Emuldan-910 = Polyoxyethylene nonyl phenol ether Surfactant whose main component is (same as above) Tween 60: Surfactant whose main component is polyoxyethylene sorbitan monostearate (same as above) Emuldan 931: Surfactant whose main component is polyoxyethylene nonyl phenol ether (Same as above) Emanone 3199: Surfactant whose main component is polyethylene glycol monostearate (Same as above) Toho Ruto A-5: Special anion type surfactant (Toho Chemical System) Toho Sol) 8M130: Special anion Type surfactant (same as above) Comparative example 1°C, I Reactive Yellow 138 PC 100 parts (
(contains 40% water) and Emulgen 91 as an additive.
0 was added to the dried product in an amount of 5%, and spray-dried in the same manner as in Example 1. The particle size of this dry product was 8% less than 200 mesh, and the amount of fine particles was larger than in Example 1, so it could not be used as a product as it was, and it was necessary to add 5% fluid pack-in as a dust-free agent. Ah, ivy. Moreover, the obtained granules during drying did not have sufficient hardness and were very easily crumbled, and this dried product had little suitability for automatic weighing.

"Effect of the Invention J By the method of the present invention, a dry granular water-soluble dye product with excellent dustless effect and a particle size suitable for automatic weighing, etc. can be obtained without impairing dyeability.

Claims (1)

[Claims] (1) A water-soluble product characterized by incorporating modified starch and a surfactant into an aqueous paste of a water-soluble dye so that the content of each in the dry product is 0.1 to 20 percent (by weight), and then spray-drying the paste. Manufacturing method for dried sex dye products