JPS63227859A - Decoloration of jeans - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method of decolorizing jeans, and in particular, it is possible to industrially advantageously obtain jeans with a good texture. Eggplant [Conventional technology] Jeans have long been popular among a wide range of generations, and in recent years, jeans that have been simply dyed and sewn have become popular, as well as faded jeans that look worn out.

Traditionally, faded jeans have been manufactured by using naturally occurring pumice as a media and rotating them in a rotating barrel with water and dyed and sewn jeans to bleach them to give them a worn-in look. The principle of decolorization by this method is as follows.

That is, when jeans absorb water, wrinkles are formed on the surface of the jeans. During the operation of the rotating barrel, the convex parts of the pleats are abraded by the media and become discolored, but the concave parts are less abraded, which allows for natural discoloration with a subtle texture.

For this reason, if a heavy material such as granite (bulk specific gravity 2.5 to 2.8) is used as the media,
During the decolorization process, the media strongly hits the unevenness of the folds during water absorption, causing the unevenness to flatten out, making it impossible to achieve natural, uneven decolorization. On the other hand, like pumice, the bulk specific gravity is 0.
．． 9 to 1.8 (Actually measured value is 1.3 to 1.6), it is possible to bleach the jeans by taking advantage of the folds during water absorption. Volcanic pumice with a bulk specific gravity of around 1.3 is used.

[Problems to be Solved by the Invention] However, when pumice stone is used, there are the following drawbacks.

■ Pumice is a brittle material and has low abrasion resistance, so it wears down during rotation treatment and generates a large amount of earth and sand (wearing material) when draining water after treatment, making wastewater treatment difficult. For example, in a normal bleaching process, approximately I kg of dirt is generated per pair of jeans.

■ For the same reason, a large amount of dirt adheres to the pockets and seams of jeans, making it difficult to wash the jeans after bleaching.

■ Due to this high amount of wear, the media must be replenished frequently, making decoloring work complicated, and
It is also economically disadvantageous.

■ Since pumice is a natural product, its hardness, particle size, and specific gravity change easily, making it difficult to manage and to perform stable decolorization.

■ Jeans can be contaminated by naturally occurring discoloring substances such as iron.

[Means for Solving the Problems] The present invention solves the above-mentioned conventional problems, and includes: bulk specific gravity of 0.7 to 1.9; 24-hour water absorption rate of 10 to 40%;
A method for decolorizing jeans, which comprises rotating an air-permeable ceramic porous body having a maximum diameter of 150 mm or less, water, and jeans in a rotating tank, and a bulk specific gravity of 0.7 to 1.9.24 hours water absorption rate of 10 to 1. 40%,
A method for decolorizing jeans, which comprises impregnating a breathable ceramic porous body with a maximum i' of 150 mm or less with a decolorizing agent solution, and rotating the decolorizing agent-impregnated breathable ceramic porous body, water, and jeans in a rotating tank. The main points are as follows.

The present invention will be explained in detail below.

The porous ceramic body having air permeability, that is, continuous pores, used in the present invention has a bulk specific gravity of 0.7 to 1.9, a 24-hour water absorption rate of 10 to 40%, and a maximum diameter of 150 mm or less.

The bulk specific gravity of the breathable ceramic porous body is a factor that affects the degree of bleaching of jeans, and if the bulk specific gravity is less than 0.7, sufficient bleaching efficiency cannot be obtained. On the other hand, the bulk specific gravity is 1.9
If it exceeds 100 mL, the degree of collision with the folds of the jeans during water absorption is too large, making it impossible to obtain jeans with a good texture by bleaching while making the most of the pleats. Especially the bulk specific gravity is about 0.8 to 1
．． It is preferable that it is about 6.

If the water absorption rate of the breathable porous ceramic body is too high, the specific gravity will increase due to water absorption, and it may not be possible to bleach the color by taking advantage of the folds of jeans. On the other hand, if the water absorption rate is too low, the impregnation efficiency when impregnating with a decoloring agent tends to be poor, and the decoloring efficiency also tends to decrease. Therefore, in the present invention, air-permeable ceramic h-yam/+x Ri A mF-11M
-& Tadashi 1. +1 0~A 1lQ4c,
The weight should be set at 20-30%.

In this specification, the 24-hour water absorption rate is defined as ``24-hour water absorption rate'' when 100 parts by weight of a dry product is immersed in water and the amount of water absorbed after 24 hours is 8 parts by weight. Expressed as a%.

In the present invention, the maximum diameter of the breathable ceramic porous body is 150 mm or less. If the diameter of the air-permeable ceramic porous body is too large, workability will deteriorate. The maximum diameter of the breathable ceramic porous body is preferably 100 mm or less.

The shape of the breathable ceramic porous body used in the present invention is not particularly limited, but for example, FIGS. 1(a) (side view), (b)
) (Front view) can be used.

In addition, the ceramic composition of the breathable ceramic porous body is
5io270-88% by weight, CaO3-23% by weight and θ
AJ! It is preferable to contain s+035 to 15% by weight.

In other words, if the ceramic has such a composition, a porous body with uniform porosity and pore radius and high hardness can be obtained. In particular, from the viewpoint of porosity, pore uniformity, and brittleness, 5i0270-80% by weight, Ca010-23% by weight
, AJ220z 5 to 15% by weight is the best range. A porous body with such a composition has a pore radius of 0.3 to
It is extremely uniform with a diameter of 50 μm.

Such an air-permeable ceramic porous body is made of siliceous waxite, preferably pyrophyllite and/or kaolin, which is a natural raw material and inexpensively supplied, and has an AIL20s content of about 13.
5% by weight or less, limestone and clay as starting materials
i0270-88% by weight, CaO3-23% by weight and A
A composition of JZ2 o35 to 15% by weight is formed, molded by a conventional method with the addition of a molding aid such as an organic binder if necessary, and the molded body is fired at 1000°C or higher to prevent the formation of oxidation during the firing reaction. Through the resulting liquid phase and solid phase reaction, an air-permeable porous body with uniform pore diameter can be easily produced.

In the method of the present invention, such an air-permeable ceramic porous body may be impregnated with a decoloring agent.

When impregnated with a decolorizing agent, the breathable ceramic porous body has a porosity of 30 to 70% and a pore size of 0.3 to 5.
It is preferable to have continuous pores of about 0 μm.

In addition, examples of the decolorizing agent used in this case include chlorine compound bleaching agents such as sodium hypochlorite, sodium chlorite, and white powder, oxidizing bleaching agents such as peroxide bleaching agents, or reducing bleaching agents.

The amount of the bleaching agent to be impregnated is appropriately determined depending on the physical properties of the breathable ceramic porous body, the degree of bleaching of the jeans, the bleaching performance of the bleaching agent used, and the like.

When a bleaching agent is used, it has a more intense bleaching effect,
It is possible to obtain jeans having a unique texture by causing natural unevenness of bleaching.

To carry out the method of the present invention, for example, FIG. 2(a) (
Using a ball mill-shaped barrel 1 as shown in (schematic side view) and (b) (front view), an air permeable ceramic porous body impregnated with a decoloring agent or not impregnated into the barrel 1 from the input port 2, Add water and jeans and rotate.

In this case, the ratio of the breathable porous ceramic material, water, and jeans to be added varies depending on the physical properties of the breathable porous ceramic material, the presence or absence of a bleaching agent, and the degree of bleaching of the jeans. It is preferable to add 1 to 20 kg of the porous porous ceramic body and 1 to 10 ft of water. The rotation time and number of rotations of the barrel are also appropriately determined depending on the physical properties of the porous porous ceramic material used, the charging ratio, the degree of decolorization, and the like.

Jeans bleached in this way are processed into products after being subjected to post-processing such as washing.

[Function] The breathable ceramic porous body has higher hardness and is less brittle than pumice, etc., so it is less likely to wear out.

Therefore, the generation of dirt and sand due to wear is reduced, making it easier to treat wastewater and finish jeans. Furthermore, since the amount of replenishment corresponding to the amount of wear only needs to be small, replenishment work and the like are reduced and efficiency is improved.

Since the body is relatively lightweight with a bulk specific gravity of 0.7 to 1.9, it takes advantage of the folds of jeans when absorbing water. It is possible to perform a light bleaching process, and jeans with a good texture can be obtained.

Furthermore, since discoloration substances such as iron derived from natural substances are not mixed into the treatment system, contamination of the jeans is prevented.

In addition, since it has a suitable water absorption property, it can be impregnated with a decolorizing agent, and in this case as well, wear can be suppressed and processing can be carried out for a long time.

[Examples] The present invention will be described in more detail with reference to Examples and Comparative Examples below, but the present invention is not limited to the following Examples unless it exceeds the gist thereof.

For convenience of explanation, a comparative example will be explained first.

Comparative Example 1 Natural pumice (bulk specific gravity 1.3.30mm (diameter) x 50mm
(Length), approx. 45g/1 piece) 15Kg.

Put 20λ of water and 4 pieces of jeans into the rotating barrel (barrel capacity 160fL) shown in Figures 1(a) and (b), and
The jeans were bleached by spinning for 7 minutes.

As a result, the jeans were able to have a light bleaching that took advantage of the folds, giving them a nice texture, but approximately 4 kg of dirt was generated due to the wear of the pumice, making it extremely difficult to treat wastewater and wash the jeans.

Example 1 Jeans were bleached in the same manner as in Comparative Example 1, except that 20 kg of a porous porous ceramic body having the following specifications was used instead of 15 kg of natural pumice.

Air permeable ceramic porous body Bulk specific gravity = 1.6 Water absorption rate: 15% Shape: Approximately cylindrical shape (50 ~
60 g/1 piece) As a result, the finish of the jeans was somewhat flatter than that of Comparative Example 1 using natural pumice, but had an extremely good texture.

On the other hand, the amount of earth and sand generated by abrasion of the porous porous porous body was approximately 500 g, which was 1/8 of that of pumice in Comparative Example 1, and the work for wastewater treatment and jeans washing was significantly reduced.

Example 2 Example 1 except that the breathable ceramic porous body used in Example 1 was impregnated with about 10 g/piece of 20% by weight sodium hypochlorite aqueous solution, and the rotation time was 17 minutes.
Processing was carried out in the same manner.

As a result, jeans having a feel similar to that obtained in Example 1 were obtained in a short processing time.

In addition, the amount of dirt due to wear was 500 g, and drainage treatment and post-treatment of the jeans were easy.

[Effects of the Invention] As detailed above, the method for decolorizing jeans of the present invention involves placing a specific porous porous porous body impregnated with a decoloring agent or not impregnated with water, and jeans in a rotating tank. Since the porous ceramic body is rotated by hand, there is less abrasion of the porous porous ceramic material, which reduces the amount of sediment generated and facilitates wastewater treatment.

■ Post-processing of jeans after bleaching becomes easier.

■ The amount and frequency of replenishment of the breathable ceramic porous body can be reduced.

Effects such as this are achieved.

Furthermore, since the breathable ceramic porous body used in the present invention is relatively lightweight, it is possible to perform light decolorization by taking advantage of the folds of jeans when they absorb water.

Moreover, there is no contamination by discoloration substances such as iron.

Furthermore, by impregnating and using a decoloring agent, more efficient decolorization can be achieved. Moreover, even in this case, the wear of the air-permeable ceramic porous body is small.

Therefore, according to the method of the present invention, jeans can be bleached at low cost and with a direct effect rate, and jeans with good texture and high product value can be obtained by bleaching.

FIGS. 1(a) and 1(b) show the air-permeable ceramic porous bodies used in Examples 1 and 2, with FIG. 1(a) being a side view and FIG. 1(b) being a front view, respectively. FIGS. 2(a) and 2(b) are views showing a rotating barrel suitable for carrying out the present invention, with (a) showing a schematic side view and FIG. 2(b) showing a front view, respectively.

! ...Barrel, 2...Inlet.

Patent applicant: Inax Co., Ltd. Representative Director Teruzo Ina

Claims (2)

[Claims] (1) Bulk specific gravity 0.7-1.9, 24-hour water absorption rate 10-4
1. A method for decolorizing jeans, which comprises rotating an air-permeable ceramic porous body with a maximum diameter of 0% and a maximum diameter of 150 mm or less, water, and jeans in a rotating tank. (2) Bulk specific gravity 0.7-1.9, 24-hour water absorption rate 10-4
0%, a breathable ceramic porous body with a maximum diameter of 150 mm or less is impregnated with a decolorizing agent solution, and the decolorizing agent-impregnated breathable ceramic porous body, water, and jeans are rotated in a rotating tank. Bleaching method.