KR100706407B1 - Low shrinkage genuine leather containing environmental friendly material - Google Patents

Abstract

The present invention relates to a method for manufacturing environmentally friendly low-shrink natural leather, and more particularly, in the manufacture of natural leather consisting of preparation, oil, dyeing and painting step, using an aldehyde-based tanning agent in the oil phase step, in the dyeing step It uses a vegetable-based retanning agent to exclude the release of harmful substances, and relates to a method for producing natural leather excellent in heat resistance, heat resistance and moisture resistance shrinkage.

Genuine Leather, Shrink, Tanning Agent, Chromium, Aldehyde

Description

Low Shrinkage Genuine Leather containing environmental friendly Material}

1 is a photograph showing the heat and moisture resistance shrinkage of the natural leather produced in Example 1 according to the present invention.

Figure 2 is a photograph showing the heat and moisture resistance shrinkage of the natural leather prepared in Example 2 according to the present invention.

Figure 3 is a photograph showing the heat and moisture resistance shrinkage of the natural leather produced in Comparative Example.

The present invention relates to a method for manufacturing environmentally friendly low-shrink natural leather, and more particularly, in the manufacture of natural leather consisting of preparation, oil, dyeing and painting step, using an aldehyde-based tanning agent in the oil phase step, in the dyeing step It uses a vegetable-based retanning agent to exclude the release of harmful substances, and relates to a method for producing natural leather excellent in heat resistance, heat resistance and moisture resistance shrinkage.

Natural leather, which is often used as automobile interior materials and general products, is a process of obtaining the final leather from the animal skin in terms of its manufacturing method, so the key is how to produce the characteristics of animal skin as mineral leather.

In addition, unlike synthetic artificial leather, natural leather has pores, so it has excellent breathability like human skin, so that sweat is not absorbed or sticky like artificial leather. In terms of sensibility, it has excellent feeling of hygroscopicity compared to artificial leather, and is often used as a material that gives high quality as expensive, necessities, and automobile interior materials.

On the other hand, automotive interior materials are commonly used for wrapping the seat and a portion of the interior material. This is because the leather shrinks differently from the synthetic tissue at high temperature and high humidity due to the characteristics of the leather. Due to these limitations, it is impossible to use it in a wide area and direct sunlight, such as an automobile crash pad.

Conventional leathers use large amounts of trivalent chromium as tanning agents for mineral leather in animal hides. This is an emulsifier for leather, and more than 80% of the current products are leather treated with chromium, which has the advantage of producing high-quality leather. However, trivalent chromium is hexavalent chromium after heat aging. It is easy to be oxidized, and in this case, it is classified as a carcinogen because it causes toxicity to human body as environmentally harmful substance.

The present inventors have tried to solve the above problems. As a result, the aldehyde tanning agent is used in the oiliness step, and the vegetable retanning agent is used in the dyeing step, and the tanning agent and the retanning agent are used to induce emulsification of the leather and to have low-shrinkability, which is excellent in heat, heat and moisture resistance. It has been found that the manufacture of leather is possible to complete the present invention.

Accordingly, an object of the present invention is to provide a method for producing natural leather having excellent heat, heat and moisture resistance.

The present invention is a method for producing natural leather consisting of the preparation, oil, dyeing and painting step,

2 to 5% by weight of the aldehyde tanning agent on the leather after the preparation step in the oiliness step,

It is characterized by a low shrinkage natural leather manufacturing method using a vegetable-based retanning agent in the dyeing step 5 to 25% by weight relative to the leather after the oily step.

Hereinafter, the present invention will be described in detail.

The present invention has a similar feature to improve the problem that the tanning agent of trivalent chromium used for mineral leather is environmental pollution and harmful to the human body, it is excellent in the tanning effect without the harmful and easy to adjust the pH during the oil process and the inside Method of manufacturing natural leather using vegetable selected from aldehydes with excellent penetrating properties and at the same time with retanning agent with good flexibility and even penetrability in leather to reduce color and property distribution variation It is about.

Conventional natural leather manufacturing process is divided into stages of preparation-oil-dyed-painting, which will be described in more detail as follows.

First, the preparation process is divided into water droplets, lime and fleshing.

Soaking is the replenishment of water lost by salting to reduce the fresh skin condition and remove dirt or water-soluble protein.Liming is alkalized to remove hair, and keratin epidermis and unnecessary protein to remove fibrous tissue. Fleshing is the removal of fat from the silver layer and the skin wrinkles.

The planetary process is then divided into deliming, betting, pickling and tanning.

Deliming is the removal of lime injected for alkalizing in the preparation process, and betting is the removal of foreign substances by the action of proteolytic enzymes of the leather, and the softening and softening of the silver surface of the leather to increase elongation and yield. Acid pickling is the use of salt and acid to control the acidity of the leather by hydrolysis of the acid to make tanning agents even during the oil phase.

In addition, tanning is a process of imparting mineral to animal properties for the commercialization of leather, which provides heat resistance and flexibility.

Generally, trivalent chromium is used to induce high physical properties of leather, but it is classified as an environmentally harmful substance and its use is expected to decrease in the future. General tanning agents include chromium, aldehydes, aluminum, phosphate, and vegetable, but leather tanning agents to replace physical properties equivalent to chromium. Leather tanning agents are used for aldehyde treatment and chromium content is less than 0.1%. In the oil process, the leather is used in the step of giving the mineral property in the animal property to impart heat resistance. The material used and the content of the tanning agent in the leather manufacturing process greatly affect the shrinkage rate.

The present invention does not simply replace aldehyde in place of trivalent chromium in this tanning process, but uses aldehydes which have one feature of excellent tanning effect, easy pH control during oily process, and excellent penetration inside the leather. It was adjusted to an appropriate range, and the technical constitution features that a specific retanning agent was selected and used in the following process.

When the aldehyde-based tanning agent is used in the oil phase step 2 to 5% by weight of the leather after the preparation step, when the amount is less than 2% by weight, the tanning effect is lowered, and in the case of more than 5% by weight, the binding force of additional drugs other than aldehyde It is preferable to maintain the above range because problems such as weakening of the physical properties such as flexibility and tensile strength due to this fall.

The dyeing process is then divided into retanning, neutralization, eggplant and drying steps.

Retanning is a relatively loose weave in the abdomen, which is a common part of animal skin, and low density tissues are thinner and harder to obtain a leather with chrome tanning. Reduce the flexibility and give elasticity, leather filling. In the present manufacturing process, there is a characteristic feature of the technical configuration of using a vegetable-based retanning agent to re-regulate the shrinkage rate given by the primary tanning agent and to control the filling feeling.

That is, in the past, TARA-based tanning agents having good heat resistance were used, but they had a problem of causing strong shrinkage under moisture resistance conditions, and vegetable tanning agents have a weaker heat resistance than TARA, but have strong characteristics against moisture conditions.

When the vegetable retanning agent is used in an amount of 5 to 25% by weight based on the leather after the oiliness step, when the amount is less than 5% by weight, the leather lacks flexibility and filling feeling, resulting in weak physical properties, inferior smoothness of the leather, and more than 25% by weight. In this case, it is preferable to maintain the above range because a problem of deterioration of inherent softness of natural leather occurs due to strength and hardening.

Neutralization raises the pH to facilitate the penetration of dyes, briquettes and oils, and gives flexibility and elasticity by matching the dyes with the dye. Drying refers to unfolding the leather and maintaining a constant moisture state.

Next, the coating process is performed, which is performed with a dye, a pigment, a binder, etc. to cover and conceal the scratches on the surface of the leather.

The following Table 1 shows the amount of the ingredients used in each step in the production of natural leather of the present invention, the blending ratio is expressed in weight percent relative to the weight of the previous step. That is, (1) the content of the drug such as detergent in the preparation process is weight% based on the weight of the raw skin, and (3) the content in the dyeing process represents the weight% of the raw skin weight after the step (2) oiliness process.

The components used above are generally used in the art except for tanning agents and retanning agents, but are not particularly limited in the present invention. In the present invention, the detergents include a degreasing agent and a hydrophilic detergent that control a nonionic surfactant, The enzyme is PROTEOLYTIC ENZYME, a proteolytic enzyme, the amine is a hair loss promoting aid, the preservative is a fungicide that does not contain organic halogen, and is a heterocyclic compound with a pH of 3.5 to 5.5. Ingredients containing organic acids. Agonists can use pancreatic enzymes that have an effect at pH 7-9, auxiliaries can be resin (RESIN0, MELAMINE), polyurethane (POLYURETHANE), protein (PROTEIN), etc. (SULPHTED ESTER & SYNTHETIC FATTY) and NATURAL FATTY, acid is formic acid, sulfuric acid, binder is polyurethane, inorganic mating agent, ironic binder (ANIONIC ACRYIC BINDER), the pigment is iron oxide (IRON OXID), carbon black (CARBON BLACK), phthalocyanine pigment (PHTHALOCYANINE PIGMENT), titanium dioxide (TITANIUM DIOXIDE), ethoxylate (ETHOXYLATE), isotridecananol ), And an X-linker may use isocyanate, epoxy, or the like.

In addition, the amount is not particularly limited to the amount generally used in the art except for the tanning agent and the retanning agent, but in the present invention, it is preferable to use each of the amounts shown in the table as described above. If the content of each component is out of the range can be partially supplemented by the control of the content somewhat, but it is preferable to maintain the above range because the problem of physical properties change because it affects the shrinkage as a low shrink leather Do.

The natural leather produced according to the present invention has a heat shrinkage of 4 to 5%, and a heat resistant and moisture resistant shrinkage of 4 to 7%.

Examples 1-2 and Comparative Example 1

Next, as shown in Tables 2 and 3, (A) aldehyde tanning agent and (B) vegetable-based retanning agent were used to prepare natural leather for testing after oily, dyeing, drying, and coating processes. At this time, the component content unit is weight%, the remaining amount after adding the amount of the component was added to maintain the water by 100% by weight.

Test Example

The physical properties of the natural leather prepared in Examples 1 and 2 and Comparative Examples were measured by the following method and the results are shown in Table 4 below.

(1) Heat shrinkage characteristics measurement

In order to measure the shrinkage of natural leather, shrinkage was evaluated under heat-resistant conditions. The test conditions are to leave the leather at 120 ° C. for 168 hours in an air convection chamber and measure the shrinkage rate before and after the test.

The test piece is A4 size and draws a square of 15 cm in width and length, and then measures the exact dimensions and measures again after the test.

(2) Heat and moisture resistance shrinkage measurement

If condition (1) simply heats temperature, shrinkage is measured by adjusting temperature and humidity to evaluate leather shrinkage in moist conditions. The test piece is same as (1), and the test conditions are as follows.

4 hours heating at 40 ℃, 90% RH-> 2 hours heating at 120 ℃-> 4 hours heating at 120 ℃-> 2 hours cooling at 40 ℃, 90% RH

As shown in Table 4, in the case of Examples 1 to 2 according to the present invention it can be seen that the shrinkage of heat, heat and moisture resistance significantly improved compared to Comparative Example 1. This result can be seen more clearly in FIG.

As described above, the present invention is a low-shrinkable natural leather with eco-friendly properties for use in automotive interior materials to improve the phenomenon of crushing and shrinking due to external conditions such as heat-resistant light, etc. And it has the advantage of maintaining the quality.

Claims (2)

In the preparation, oil, dyeing and coating step of natural leather manufacturing method, 2 to 5% by weight of the aldehyde tanning agent on the leather after the preparation step in the oiliness step, A low shrinkage natural leather manufacturing method characterized by using a vegetable-based retanning agent in the dyeing step 5 to 25% by weight based on the leather after the oily step. The method of claim 1, wherein the natural leather has a heat shrinkage of 4 to 5% range, the low shrinkage natural leather manufacturing method characterized in that the heat and moisture resistance shrinkage is maintained in the range of 4 to 7%.

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