阅读说明：本技术 一种利用低等级皮源制备油蜡皮的方法 (Method for preparing oil wax skin by using low-grade skin source ) 是由 王辉达 周斌 于君德 王刚林 于 2020-08-11 设计创作，主要内容包括：本发明公开了一种利用低等级皮源制备油蜡皮的方法,该方法选用低等级蓝皮作为原料,先利用复鞣工艺对低等级蓝皮进行预处理,来将皮性调紧实,获得耐磨、耐模压的皮坯,然后利用补伤膏配合抛光蜡进行刷补；刷补完成后利用通过式磨革机配合特定目数的砂纸磨去表面补伤膏以及粒面层,再进行辊涂操作,并在辊涂过程中利用模压板进行多次低温、低压模压,辊涂完成后晾干即得到成品油蜡皮。本发明可对低等级皮源进行高效利用,制备的油蜡皮强度和耐磨性能佳,纹路均匀饱满突出,伤痕可见度低,适合于作为鞋用皮革。(The invention discloses a method for preparing oil wax leather by using a low-grade leather source, which comprises the steps of selecting low-grade blue leather as a raw material, pretreating the low-grade blue leather by using a retanning process to compact the leather property to obtain a wear-resistant and mould-pressing-resistant leather blank, and then brushing and mending by using a mending paste matched with polishing wax; and after finishing the brushing, grinding the surface repairing paste and the grain surface layer by using a pass type leather grinder in combination with abrasive paper with a specific mesh number, then performing roller coating operation, performing low-temperature and low-pressure mould pressing for multiple times by using a mould pressing plate in the roller coating process, and airing after finishing the roller coating to obtain the finished product of the oil wax leather. The invention can efficiently utilize low-grade leather sources, and the prepared oil wax leather has good strength and wear resistance, uniform, full and prominent grains and low scar visibility, and is suitable for being used as leather for shoes.)

1. A method for preparing oil wax skin by using low-grade skin source is characterized by comprising the following operation steps:

s1, selecting low-grade blue leather as a raw material, pretreating the low-grade blue leather by using a retanning process, and modifying the low-grade blue leather by using an acrylic acid retanning agent, an amino resin retanning agent, a plant tanning agent and a modified tannin extract as a combined tanning agent during retanning, wherein the adding proportion of the combined tanning agent is 1.1-1.25 of that of the combined tanning agent in the retanning process for the same batch of high-grade blue leather, so that the wear resistance and the compression resistance of the low-grade blue leather raw material are fully improved;

s2, spreading and finishing the retanned leather, wherein brushing and repairing and buffing the leather surface wound in sequence during finishing; when brushing and mending are carried out, mending paste is matched with polishing wax for brushing and mending; after finishing the brushing, grinding the surface repairing paste by using a pass type leather grinding machine together with No. 600-800 abrasive paper, and grinding the grain surface layer together to desalt the damaged part of the leather material;

s3, roller coating a coating material on the surface of the leather treated by the leather grinder by a roller coating method, wherein the coating material is oil wax, the roller coating is carried out for three times, the first roller coating and the second roller coating are respectively followed by mould pressing by a mould pressing plate, the mould pressing is carried out for multiple times under the conditions of low temperature and low pressure of less than 90 ℃ and 80-85 pa, the mould pressing is carried out for 15-30 seconds for a single time, the mould pressing is carried out for 3-5 times in a circulating manner, then the roller coating of the coating material is carried out for the third time, and the finished product oil wax leather is obtained after the roller coating is finished and.

2. The method for preparing the oil wax leather by using the low-grade leather source as claimed in claim 1, wherein the mass ratio of the acrylic acid retanning agent in the combined tanning agent is 20-30%; the mass ratio of the amino resin retanning agent is 12-17%; the mass ratio of the modified tannin extract is 5-8%; the balance of plant tanning agent.

3. The method for preparing the oil wax leather by using the low-grade leather source as claimed in the claim 1, wherein before the retanning process of the step S1, the low-grade blue leather raw material is softened and neutralized by acid washing, and the combined tanning agent is added in three times after the low-grade blue leather raw material is fully softened, wherein the first adding amount is 25-30 wt%, the second adding amount is 7-15%, and the rest of the combined tanning agent is added in the third time.

4. The method for preparing wax skin using low-grade skin source as claimed in claim 1, wherein the step S2 is to use mending paste and polishing wax, preferably mending paste PPF with strong covering property and polishing wax 1747.

5. The method for preparing waxed hides according to the low-grade hide source of claim 1, wherein step S2 is repeated several times in treatment of the hides with obvious damages and defects, and step S2 is repeated several times in treatment of the through-type hides grinding machine, wherein the sandpaper with smaller mesh is used first, and then the mesh of the sandpaper used in the through-type hides grinding machine is sequentially increased.

6. The method for preparing oil wax skin by using low-grade skin source according to claim 1, wherein when the mould pressing is carried out in the step S3, the mould pressing plate is a simulated pore mould pressing plate.

Technical Field

The invention relates to the technical field of leather preparation, in particular to a method for preparing oil wax leather by using a low-grade leather source.

Background

The cow hide is growing, slaughters, transportation, processing engineering, because various reasons can make the skin blank surface produce the face disability problems such as unsmooth, the pore is coarse, there is the scar, the existence of these disabilities has influenced the outward appearance and the rate of utilization of leather, reduces the leather grade, reduces the leather utilization ratio, causes the wasting of resources easily, consequently, how to promote the leather grade is the present leather field and awaits the technological problem who solves urgently.

The low-grade leather blank is a great problem troubling leather factories, and the development of a shaving product aiming at the problem is the most effective and direct method. The traditional leather finishing process is complex in process, the obtained leather is weak in natural property, the property of the leather is influenced, and the product quality grade is low.

The oil wax leather has a special leather feeling effect formed by polishing, oiling and waxing the first layer cowhide, is high-grade leather, and has a high price as the first layer leather serving as a raw material of the oil wax leather. If the low-grade leather blank can be prepared into the wax oil leather by the leather finishing process, the actual problem of the leather source can be solved, and the product requirements of the market can be met.

Disclosure of Invention

The technical problem to be solved by the invention is to provide the method for preparing the oil wax leather by using the low-grade leather source, which can efficiently utilize the low-grade leather source, improve the added value of the low-grade leather source product and solve the defects in the technical background.

The technical problem solved by the invention is realized by adopting the following technical scheme:

a method for preparing oil wax skin by using low-grade skin source comprises the following operation steps:

s1, selecting low-grade blue leather as a raw material, pretreating the low-grade blue leather by using a retanning process, and modifying the low-grade blue leather by using an acrylic acid retanning agent, an amino resin retanning agent, a plant tanning agent and a modified tannin extract as a combined tanning agent during retanning, wherein the adding proportion of the combined tanning agent is 1.1-1.25 of that of the combined tanning agent in the retanning process for the same batch of high-grade blue leather, so that the wear resistance and the compression resistance of the low-grade blue leather raw material are fully improved;

s2, spreading and finishing the retanned leather, wherein brushing and repairing and buffing the leather surface wound in sequence during finishing; when brushing and mending are carried out, mending paste is matched with polishing wax for brushing and mending; after finishing the brushing, grinding the surface repairing paste by using a pass type leather grinding machine together with No. 600-800 abrasive paper, and grinding the grain surface layer together to desalt the damaged part of the leather material;

s3, roller coating a coating material on the surface of the leather treated by the leather grinder by a roller coating method, wherein the coating material is oil wax, the roller coating is carried out for three times, the first roller coating and the second roller coating are respectively followed by mould pressing by a mould pressing plate, the mould pressing is carried out for multiple times under the conditions of low temperature and low pressure of less than 90 ℃ and 80-85 pa, the mould pressing is carried out for 15-30 seconds for a single time, the mould pressing is carried out for 3-5 times in a circulating manner, then the roller coating of the coating material is carried out for the third time, and the finished product oil wax leather is obtained after the roller coating is finished and.

As a further limitation, the mass ratio of the acrylic acid retanning agent in the combined tanning agent is 20-30%; the mass ratio of the amino resin retanning agent is 12-17%; the mass ratio of the modified tannin extract is 5-8%; the balance of plant tanning agent.

By way of further limitation, before the retanning process of the step S1 is carried out, the low-grade blue leather raw material is softened and neutralized by acid washing, and the combined tanning agent is added into the low-grade blue leather raw material in three times after the low-grade blue leather raw material is fully softened, wherein the first adding amount is 25-30 wt%, the second adding amount is 7-15%, and the balance of the combined tanning agent is added into the combined tanning agent in the third time.

Further, the repair paste and the polishing wax used in step S2 are preferably repair paste PPF and polishing wax 1747 having high covering properties.

Further, when the leather material with significant damage and chipping is treated, the step S2 may be performed repeatedly, and when the step S2 is performed repeatedly, the sand paper with a smaller mesh size is used first and then the sand paper with a larger mesh size is used for the treatment by the pass-through type leather grinder.

By way of further limitation, when the mold pressing is performed in step S3, the mold pressing plate preferably adopts a simulated pore plate to make natural and clear pore patterns close to the dermis.

Has the advantages that: the method for preparing the oil wax leather by using the low-grade leather source can repair and treat the low-grade leather source to obtain the oil wax leather with higher quality, the prepared oil wax leather keeps natural properties of softness, air permeability and the like of genuine leather, the leather surface is oily and plump, the concealment of defective parts is good, the wear resistance is good, the oil wax leather is suitable for being used as a shoe upper leather, the grade rate of finished products of the low-grade leather source can be improved, the digestion of the low-grade leather source is facilitated, and the additional value of raw materials of the oil wax leather is increased.

Detailed Description

In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further described with the specific embodiments.

In the examples, the preparation of the oil wax leather from low-grade leather sources is carried out according to the following sequence of steps, the use of different reagents is different due to the difference of the leather quality, and the corresponding operation sequence should not be changed so as to avoid affecting the processing quality.

In the embodiment, the skin of the low-grade blue hide is American bull napaba embryo skin, the selected low-grade blue hide is subjected to conventional water squeezing, shaving, weighing, rinsing, acid washing for softening and neutralizing after rinsing, retanning again, a combined tanning agent is added during retanning, the adding amount of the combined tanning agent is 1.2 times of the amount of the retanning agent added in the same batch of American bull napa embryo skin retanning process, the combined tanning agent is added for three times, the adding amount of the combined tanning agent for the first time is 25-30 wt%, the adding amount of the combined tanning agent for the second time is 7-15%, and the balance of the combined tanning agent is added for the third time, wherein the combined tanning agent comprises the following components:

acrylic acid retanning agent: RE (original BASF company), RAM (BISQ company) and ANG (KeKai company) in a mass ratio of 1:1: 1;

amino resin retanning agent: r7 (Langshen), BCA-7 (TFL Co.), with a mass ratio of 3: 1;

vegetable tanning agent: adding bark ME and quebracho ATO in a mass ratio of 3: 2;

and chestnut tannin extract TCR

Wherein the dosage of the acrylic acid retanning agent is 35wt%, the dosage of the amino resin retanning agent is 15wt%, the dosage of the plant retanning agent is 43wt%, and the dosage of the castanea mollissima tannin extract TCR is 7 wt%.

The combined tanning agent with the proportion is matched with a retanning procedure to set the leather property of low-grade blue leather, the leather property can be tightly adjusted, the leather surface is required to be more wear-resistant and pressure-resistant, and the tightness of the leather core is fully enhanced.

Finishing after retanning, wherein the finishing process comprises repairing damaged leather surface by brushing and roller coating, and repairing by brushing with high-covering repair paste PPF (petrochemical engineering) combined with polishing wax 1747 (Demingfu Co., Ltd.) to achieve high polishing and waxing effects while solving the problems of damaged leather and grade rate of low-grade leather; after finishing the brushing and repairing, a passing-type leather grinding machine is used for grinding the surface repairing paste by 600 plus 800# abrasive paper until the grain surface layer is lightly ground to desalt the damaged part,

if the leather surface disability can not be remedied by single brushing, brushing and leather grinding are repeatedly carried out, wherein the brushing and repairing operation is consistent with the brushing and repairing operation, and when the leather grinding operation is carried out, the abrasive paper with smaller meshes is firstly utilized and then the abrasive paper with larger meshes is adopted according to the leather grinding times. In the embodiment, the leather surface wound is repaired by brushing and buffing for three times, wherein 600-mesh sand paper is used for buffing for the first time, 700-mesh sand paper is used for buffing for the second time, and 800-mesh sand paper is used for buffing for the third time.

After the leather is ground, coating and chemical material roller coating are carried out through a roller coating machine in a roller coating method, a flat surface is made, and the utilization rate is improved. During roll coating, oil wax coating is used for making a full-grain oil wax skin style, the wax coating is carried out for three times, one round of die pressing is respectively carried out by using a simulated pore plate after primary coating and middle layer slurry coating so as to make natural and clear pore patterns close to genuine leather, the die pressing temperature during die pressing is 75 ℃, the die pressing pressure is 80pa, each round of die pressing comprises three times, the die pressing time is 20S each time, the die pressing is lifted for 5S after the first die pressing is finished, then the second die pressing is carried out, the die pressing is lifted for 8S after the second die pressing is finished, and then the third die pressing is carried out; and coating the chemical material for the third time, rolling and airing to obtain the finished product of the oil wax skin.

The finished product of the wax leather is close to natural and clear pore lines of leather, the grade of a leather blank is greatly improved, the hiding performance of the damaged leather surface is good, the leather also keeps natural attributes of the leather such as softness, air permeability and the like, the leather surface is oily, full and good in wear resistance, and is blackish and glossy after being polished, so that the wax leather is particularly suitable for being used as the leather surface of a hard leather shoe.

Unless otherwise indicated, the techniques employed in the examples are conventional and well known to those skilled in the art, and the reagents and products employed are also commercially available. Various procedures and methods not described in detail are conventional methods well known in the art, and the source, trade name, and if necessary, the constituents of the reagents used are indicated at the first appearance.

The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.