KR100471465B1 - Preparation of dye for leather - Google Patents

Abstract

The present invention is a new dye that is excellent in permeability without harmful to the human body and has good fixing ability when dyeing leather, and has good uniformity, and does not cause defects, thereby grafting polymer particles to inorganic particles such as titanium dioxide, silica, alumina, and carbon black. To provide a method for producing a dye that can be used as leather, toner, or the like by encapsulating or microencapsulating.

Description

Manufacturing method of dye for leather {Preparation of dye for leather}

Dyeing began as an example in clothing and household goods, and dyes have been mainly extracted from natural animals and plants until the late 19th century. However, since perkin first manufactured synthetic dyes in 1856, dyeing products, along with technical development of organic chemical and petroleum products, Technology has developed remarkably. Currently there are more than 4,000 dyes, but only a few of them are used as leather dyes due to their specificity. In particular, C. I Direct Black 38 dye was used as a black dye dyeing leather. However, because the dyes are manufactured using benzidine, a carcinogenic intermediate, the United States has already banned the processed products dyed with these dyes. Recently, in Germany, these dyes are classified as MAK III Al group, that is, carcinogenic dyes. The regulation is gradually spreading worldwide, such as banning imports from April 1, 1996, and banning distribution from October 1, 1996 for processed products that come into contact with the human body dyed with this dye. In addition, dyes (not the MAK group) have been mentioned in US Pat. No. 4,469,906 as other black dyes, which have problems such as poor color and color fastness and lack of permeability during leather dyeing, resulting in poor dyeing.

In addition, various methods of encapsulating the polymer on the surface of the inorganic particle have been developed, but it is very difficult to encapsulate the hydrophobic polymer on the surface of the inorganic particle because the surface of the inorganic particle is hydrophilic.

The present invention has been made to solve the problems of the prior art, the object of the invention was to invent a new dye that is not harmful to the human body and excellent in penetrability, excellent fixing ability and good uniformity when dyeing leather does not occur bad.

The present invention is to provide a method for producing a dye that can be used as a leather, a toner, or the like by grafting or microencapsulating polymer particles into inorganic particles such as titanium dioxide, silica, alumina, carbon black, and the like.

The present invention disperses inorganic particles titanium dioxide, silica, alumina, carbon black and the like in distilled water in which a dispersant is dissolved, and adds hydrophilic monomers such as (meth) acrylic acid, (meth) acrylate, and (meth) acrylamide to the solution described above. The present invention relates to a method for producing a dye encapsulated in a polymer material by adding and copolymerizing hydrophobic monomers such as vinyl acetate and methyl (meth) methacrylate to the copolymer.

The inorganic particles used in the present invention are titanium dioxide, silica, alumina, carbon black and the like, and titanium dioxide is preferably used for producing white dyes and carbon black is used for black dyes.

As the hydrophilic monomer used in the present invention, (meth) acrylic acid, (meth) acrylate, (meth) acrylamide, hydroxyethyl (meth) acrylate, maleic anhydride, maleic acid, ethylene glycol (meth) acrylate, and the like can be used. It is preferable to use (meth) acrylic acid, (meth) acrylic acid salt, maleic anhydride, and maleic acid especially.

Hydrophobic monomers used in the present invention include acrylonitrile, methyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, propyl (meth) acrylate, hexyl (meth) acrylate, (methyl Styrene, vinyl acetate, and the like, and it is particularly preferable to use monomers having a low glass transition temperature such as butyl (meth) acrylate, isobutyl (meth) acrylate, and vinyl acetate.

In the present invention, a crosslinking agent may be used, and methylenebis acrylamide, ethylene glycol di (meth) acrylate, divinylbenzene, and the like may be used as the crosslinking agent.

As the dispersant used in the present invention, polyvinylpyrrolidone, polyvinyl alcohol, CMC, isopropyl cellulose, sodium alginate and the like can be used, and the dispersant is added 0.5 to 0.5%. Emulsifiers can also be used together.

Emulsifiers include ESPR-25 (polyglycerine polylinoleate, HLB = 0.5), ES-7 (glycerin monostearate, HLB = 3.8-4.3), SPAN-60 (sorbitan stearate, HLB = 6.8-8.6), SE-11 (sucrose fatty acid ester, HLB = 11), MP-8, TW-80, TW-20 (sorbitanlaurate + ethylene oxide, HLB = 16) is preferably used. These emulsifiers may be used alone or in combination of two or more thereof. The emulsifier is added in an amount of 1% to 8% based on the total amount of the solution.

As the solvent used in the reaction of the present invention, alcohols such as distilled water, ethanol, methanol, and propanol may be used, and may be mixed and used at a constant ratio.

Hereinafter, the present invention will be described in more detail as follows, but the present invention is not limited thereto.

Example 1

Into a 30L reactor equipped with a stirrer, a thermometer and a vacuum distillation apparatus, 7 kg of carbon black having an average particle diameter of 0.3 μm was added to 10 kg of polypyrrolidone 1% aqueous solution, 0.5 kg of acrylic acid was added to make a slurry, and 2.5 kg of vinyl acetate was added to the slurry. Was added. Then, 30 g of potassium peroxide was added as an initiator and reacted at 70 ° C. for 10 hours to prepare a black dye in which the polymer was encapsulated. The dye particle size produced at this time was 0.5 micrometer.

Example 2

 It carried out similarly to Example 1 except having used the titanium dioxide which is 0.2 micrometer. The dye particle size produced at this time was 0.45 탆.

Example 3

It carried out similarly to Example 1 except having used maleic anhydride as a hydrophilic monomer. The dye particle size produced at this time was 0.45 탆.

Example 4

The same procedure as in Example 1 was carried out except that maleic anhydride was used as the hydrophilic monomer and titanium dioxide having 0.2 μm as the inorganic particles. The dye particle size produced at this time was 0.4 μm.

When modifying the surface of inorganic particles based on inorganic particles and grafting or microencapsulating a polymer material, it is a dye that is harmless to the human body. It is excellent in permeability, adhesion, dyeing property of leather, etc. It is expected to be applicable to other fields.

Claims (5)

Dispersing any one or more inorganic particles selected from titanium dioxide, silica, alumina, and carbon black in distilled water in which a dispersant is dissolved; Any one selected from (meth) acrylic acid, (meth) acrylate, (meth) acrylamide, hydroxyethyl (meth) acrylate, maleic anhydride, maleic acid and ethylene glycol (meth) acrylate in distilled water in which the inorganic particles are dispersed. Adding at least one hydrophilic monomer; Acrylonitrile, methyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, propyl (meth) acrylate, hexyl (meth) acrylate, (methyl) to the solution to which the said hydrophilic monomer was added A method for producing a dye for leather, comprising the steps of encapsulating a polymer material by adding and copolymerizing any one or more hydrophobic monomers selected from styrene and vinyl acetate. delete delete delete The dispersant used according to claim 1, wherein the used dispersant is selected from polyvinylpyrrolidone, polyvinyl alcohol, CMC, isopropyl cellulose, sodium alginate, ESPR-25, ES-7, SPAN-60, SE-11, TW-20 It is any 1 or more types, The manufacturing method of the dye for leather