CN114687221B

CN114687221B - Wear-resistant foaming PU layer, synthetic leather and preparation method thereof

Info

Publication number: CN114687221B
Application number: CN202210317463.5A
Authority: CN
Inventors: 高金岗; 高义松; 张哲�; 李超
Original assignee: Suzhou Rui High Tech Materials Co ltd
Current assignee: Suzhou Rui High Tech Materials Co ltd
Priority date: 2022-03-29
Filing date: 2022-03-29
Publication date: 2024-05-03
Anticipated expiration: 2042-03-29
Also published as: CN114687221A

Abstract

The application relates to the field of synthetic leather, and particularly discloses a wear-resistant foaming PU layer, synthetic leather and a preparation method thereof. The wear-resistant foaming PU layer comprises the following raw materials in parts by weight: 90-110 parts of polycarbonate polyurethane, 0.3-0.7 part of polyether modified polydimethylsiloxane, 0.3-0.7 part of silane coupling agent and 5-10 parts of paper pulp powder. According to the application, the pulp powder improves the compatibility of the raw materials of the wear-resistant foaming PU layer, so that the raw materials of the wear-resistant foaming PU layer are uniformly mixed; the silane coupling agent enables the pulp powder to be combined with the polycarbonate polyurethane, the length-diameter ratio of the pulp powder is high, the fibers are relatively fine, and the pulp powder and the polycarbonate polyurethane are connected with each other in the wear-resistant foaming PU layer, so that the wear-resistant performance of the wear-resistant foaming PU layer is improved.

Description

Wear-resistant foaming PU layer, synthetic leather and preparation method thereof

Technical Field

The application relates to the field of synthetic leather, in particular to a wear-resistant foaming PU layer, synthetic leather and a preparation method thereof.

Background

The synthetic leather is generally prepared by taking impregnated non-woven fabric as a reticular layer and taking a microporous polyurethane layer as a grain surface layer, and has quite similar front and back sides to those of natural leather and certain air permeability, and is more similar to that of natural leather than common artificial leather.

With the rapid development of science and technology and the improvement of living standard of people, people use more and more synthetic leather, but the wear resistance of common synthetic leather is not strong, for example, the synthetic leather on basketball needs to be rubbed with the ground for a long time, thereby influencing the service life of the basketball.

Disclosure of Invention

In order to improve the wear resistance of the synthetic leather, the application provides a wear-resistant foaming PU layer, the synthetic leather and a preparation method thereof.

In a first aspect, the application provides a wear-resistant foaming PU layer, which adopts the following technical scheme:

The wear-resistant foaming PU layer comprises the following raw materials in parts by weight: 90-110 parts of polycarbonate polyurethane, 0.3-0.7 part of polyether modified polydimethylsiloxane, 0.3-0.7 part of silane coupling agent and 5-10 parts of paper pulp powder.

By adopting the technical scheme, the polycarbonate polyurethane has high tensile strength and high hardness; the pulp powder improves the compatibility of the raw materials of the wear-resistant foaming PU layer, so that the raw materials of the wear-resistant foaming PU layer are uniformly mixed; the silane coupling agent enables the pulp powder to be combined with the polycarbonate polyurethane, the length-diameter ratio of the pulp powder is high, the fibers are relatively thin, and the pulp powder and the polycarbonate polyurethane are connected with each other in the wear-resistant foaming PU layer, so that the wear-resistant performance of the wear-resistant foaming PU layer is improved; the polyether modified polydimethylsiloxane can further improve the compatibility of raw materials of the wear-resistant foaming PU layer while playing a leveling role, so that the wear-resistant performance of the wear-resistant foaming PU layer is better, and the wear-resistant performance of the synthetic leather prepared by using the wear-resistant foaming PU layer is stronger.

In a specific embodiment, the weight ratio of the pulp powder to the polycarbonate polyurethane is 1: (12-13).

By adopting the technical scheme, the proportion of the paper pulp powder and the polycarbonate polyurethane is further limited, so that the wear resistance of the wear-resistant foaming PU layer is improved.

In a specific implementation, the raw materials of the wear-resistant foaming PU layer further comprise 1-3 parts by weight of quartz sand.

By adopting the technical scheme, the addition of the quartz sand improves the anti-skid performance of the wear-resistant foaming PU layer, and further improves the wear-resistant performance of the wear-resistant foaming PU layer.

In a second aspect, the application also provides synthetic leather, which adopts the following technical scheme:

The utility model provides a synthetic leather, includes the base cloth layer, be provided with on the base cloth layer wear-resisting foaming PU layer, wear-resisting foaming PU layer deviates from be provided with on the lateral wall of base cloth layer and grind fine hair sense the surface course, grind fine hair sense the surface course deviate from be provided with antibiotic treatment layer on the lateral wall of wear-resisting foaming PU layer.

By adopting the technical scheme, the wear-resistant foaming PU layer enables the synthetic leather to have stronger wear resistance, thereby prolonging the service life of basketball made of the synthetic leather; the velvet surface layer is ground to enable the surface of the synthetic leather to have a layer of astringent feel, so that basketball made of the synthetic leather is endowed with strong grasping feel; the antibacterial treatment layer enables the synthetic leather to have certain antibacterial performance, so that the safety of the synthetic leather is improved.

In a specific embodiment, the raw material of the antibacterial treatment layer is a mixture of an anti-slip resin and an antibacterial mildew inhibitor.

By adopting the technical scheme, the anti-skid resin further improves the anti-skid performance of the synthetic leather, and the antibacterial mildew-proof agent endows the synthetic leather with certain antibacterial mildew-proof performance.

In a specific embodiment, the base fabric layer is one of a leather base fabric, a knitted fabric, a woven fabric, and a nonwoven fabric.

In a third aspect, the application also provides a preparation method of the synthetic leather, which adopts the following technical scheme:

the preparation method of the synthetic leather comprises the following steps:

Preparation of a wear-resistant foaming PU layer: adding polyether modified polydimethylsiloxane, a silane coupling agent, pulp powder and DMF into polycarbonate polyurethane, and uniformly stirring and mixing to obtain a mixture; coating the mixture on a base cloth layer, then putting the base cloth layer into water containing DMF for reaction, and foaming on the base cloth layer to form an abrasion-resistant foaming PU layer;

Preparation of a ground velvet surface layer: polishing the wear-resistant foaming PU layer to form a polishing velvet surface layer;

shaping; and arranging an antibacterial treatment layer on the ground velvet surface layer to prepare the synthetic leather.

By adopting the technical scheme, polycarbonate polyurethane, polyether modified polydimethylsiloxane, a silane coupling agent, pulp powder and DMF are uniformly mixed, then the mixture is coated on a base cloth layer, the base cloth layer is put into DMF-containing water, and an abrasion-resistant foaming PU layer is formed by foaming; and polishing the wear-resistant foaming PU layer to obtain a ground velvet surface layer, and finally arranging an antibacterial treatment layer on the ground velvet surface layer to obtain the synthetic leather with good wear resistance and antibacterial property.

In a specific embodiment, in the preparation step of the wear-resistant foaming PU layer, the base cloth layer coated with the mixture is put into water containing DMF for reaction for 15-25 min.

By adopting the technical scheme, when the reaction time is less than 15min, insufficient reaction can be caused, and the wear resistance of the prepared synthetic leather is affected; when the reaction time is longer than 25min, the raw materials on the base cloth layer are lost, and the wear resistance of the prepared synthetic leather is also affected; the reaction time is 15-25 min, so that the abrasion resistance of the synthetic leather is high.

In a specific embodiment, in the step of preparing the abrasive velvet surface layer, the abrasion-resistant foaming PU layer is polished by using abrasive paper with the mesh number of 180-220.

By adopting the technical scheme, when the mesh number of the sand paper is smaller than 180, the ground velvet feeling surface layer is rough, so that the hand feeling of the prepared synthetic leather is influenced; when the mesh number of the sand paper is more than 220, the ground velvet feeling surface layer is smoother, and the basketball is inconvenient to grasp by the synthetic leather; the abrasive paper has the mesh number of 180-220, so that the basketball made of the synthetic leather has good hand feeling and is convenient to grasp.

In a specific embodiment, in the molding step, an antibacterial and mildew-proof agent is added into the anti-slip resin, and uniformly stirred to obtain a surface treating agent, and the surface treating agent is coated on the ground velvet sensing surface layer to form an antibacterial treatment layer, so that the synthetic leather is obtained.

In summary, the present application includes at least one of the following beneficial technical effects:

1. the polycarbonate polyurethane has high tensile strength and high hardness; the pulp powder improves the compatibility of the raw materials of the wear-resistant foaming PU layer, so that the raw materials of the wear-resistant foaming PU layer are uniformly mixed; the silane coupling agent enables the pulp powder to be combined with the polycarbonate polyurethane, the length-diameter ratio of the pulp powder is high, the fibers are relatively thin, and the pulp powder and the polycarbonate polyurethane are connected with each other in the wear-resistant foaming PU layer, so that the wear-resistant performance of the wear-resistant foaming PU layer is improved; the polyether modified polydimethylsiloxane has a leveling effect, and meanwhile, the compatibility of raw materials of the wear-resistant foaming PU layer can be further improved, so that the wear-resistant performance of the wear-resistant foaming PU layer is better, and the wear-resistant performance of the synthetic leather prepared by using the wear-resistant foaming PU layer is stronger;

2. according to the application, the addition of the quartz sand improves the anti-skid performance of the wear-resistant foaming PU layer, and further improves the wear-resistant performance of the wear-resistant foaming PU layer;

3. according to the method, the wear-resistant foaming PU layer is polished by using the sand paper with the mesh number of 180-220, so that the basketball made of the synthetic leather has good hand feeling and is convenient to grasp.

Drawings

Fig. 1 is a schematic structural view for embodying synthetic leather in an embodiment of the present application.

Reference numerals illustrate: 1. a base cloth layer; 2. a wear-resistant foaming PU layer; 3. grinding the velvet surface layer; 4. an antimicrobial treatment layer.

Detailed Description

The present application will be described in further detail with reference to examples.

All the starting materials in the examples are commercially available. Wherein the polycarbonate type polyurethane is provided by a camphorwood head Hong Gai plasticizing business in Dongguan city, and the model is TPU; the polyether modified polydimethylsiloxane is organosilicon leveling agent polyether modified polydimethylsiloxane 350 provided by Shanghai Ke Raman reagent Co; the anti-skid resin is provided by Shanghai Zhan New Material science and technology Co., ltd, and EINECS number is aqueous matte anti-astringent anti-skid resin DL1080B; the antibacterial mildew preventive is Wagao DC-30, which is provided by Shanghai Wagao biotechnology Co., ltd; the silane coupling agent is silane coupling agent KH-560, which is manufactured by Wuhan energy kernel pharmaceutical chemical company, inc.; PVC artificial leather is provided by Yupeng plastics industry Co., ltd.

Examples

Example 1

Referring to fig. 1, embodiment 1 provides a synthetic leather, including a base cloth layer 1, a wear-resistant foaming PU layer 2 is formed on the base cloth layer 1, a grinding velvet surface layer 3 is disposed on a side wall of the wear-resistant foaming PU layer 2, which is away from the base cloth layer 1, and an antibacterial treatment layer 4 is coated on a side wall of the grinding velvet surface layer 3, which is away from the wear-resistant foaming PU layer 2.

Example 1 also provides a method for preparing synthetic leather, comprising the following steps:

preparation of wear-resistant foaming PU layer 2: adding 135kg of DMF into a stirring tank, adding 5kg of paper pulp powder, stirring and mixing uniformly, then sequentially adding 90kg of polycarbonate polyurethane, 0.3kg of silane coupling agent, 5kg of color paste and 0.3kg of polyether modified polydimethylsiloxane, and stirring and mixing uniformly to obtain a mixture; coating the mixture on a base cloth layer 1, then placing the base cloth layer 1 coated with the mixture into a coagulation tank containing DMF and water for reaction for 20min, and foaming on the base cloth layer 1 to form a wear-resistant foaming PU layer 2; the base cloth layer 1 is made of leather base cloth; the weight ratio of DMF to water in the coagulation tank was 1:4.

Preparation of the abrasive velvet surface layer 3: polishing the wear-resistant foaming PU layer 2 by using 200-mesh sand paper to form a polishing velvet surface layer 3;

shaping; adding an antibacterial mildew inhibitor into the anti-skid resin, wherein the weight ratio of the antibacterial mildew inhibitor to the anti-skid resin is 1: and 24, uniformly stirring to obtain a surface treating agent, and coating the surface treating agent on the ground velvet surface layer 3 to form an antibacterial treatment layer 4, thereby preparing the synthetic leather.

As shown in table 1, the main difference between examples 1 to 7 is the different raw material ratios of the abrasion-resistant foamed PU layer 2.

Table 1 composition and formulation of abrasion-resistant foamed PU layer 2 in examples 1 to 7

Sample of	DMF（kg）	Pulp powder (kg)	Polycarbonate polyurethane (kg)	Silane coupling agent (kg)	Color paste (kg)	Polyether modified polydimethylsiloxane (kg)
							Example 1	135	5	90	0.3	5	0.3
Example 2	150	8	100	0.5	8	0.5
							Example 3	165	10	110	0.7	12	0.7
Example 4	150	8	90	0.5	8	0.5
							Example 5	150	8	96	0.5	8	0.5
Example 6	150	8	104	0.5	8	0.5
							Example 7	150	8	110	0.5	8	0.5

Example 8

Example 8 differs from example 2 in that after the polyether-modified polydimethylsiloxane was added, 2kg of quartz sand was further added and stirred and mixed uniformly to obtain a mixture.

Example 9

Example 9 differs from example 8 in that the base fabric layer 1 was placed in a coagulation tank containing DMF and water to react for 10min.

Example 10

Example 10 differs from example 8 in that the base fabric layer 1 was placed in a coagulation tank containing DMF and water for reaction for 15min.

Example 11

Example 11 differs from example 8 in that the base fabric layer 1 was placed in a coagulation tank containing DMF and water for reaction for 25min.

Example 12

Example 12 differs from example 8 in that the base fabric layer 1 was placed in a coagulation tank containing DMF and water for reaction for 30min.

Example 13

Example 13 differs from example 8 in that a knitted fabric was used as the base fabric layer 1.

Example 14

Example 14 differs from example 8 in that the base fabric layer 1 is a woven fabric.

Example 15

Example 15 differs from example 8 in that nonwoven fabric is used as the base fabric layer 1.

Example 16

Example 16 differs from example 8 in that the non-slip resin is replaced with an equivalent amount of aqueous polyurethane resin.

Example 17

Example 17 differs from example 8 in that 160 mesh sandpaper was selected to sand the abrasion resistant foamed PU layer 2 to form the abrasive velvet surface layer 3.

Example 18

Example 18 differs from example 8 in that the abrasion-resistant foamed PU layer 2 was sanded with 180 mesh sandpaper to form the abrasive velvet surface layer 3.

Example 19

Example 19 differs from example 8 in that the abrasion-resistant foamed PU layer 2 was sanded with 220 mesh sandpaper to form the abrasive velvet surface layer 3.

Example 20

Example 20 differs from example 8 in that 240 mesh sandpaper was selected to sand the abrasion resistant foamed PU layer 2 to form the abrasive velvet surface layer 3.

Application example 1

Basketball was made using the synthetic leather of example 2.

Application examples 2 to 7 are different from application example 1 in that synthetic leather is used, and the details are shown in the following table.

Table 2 selection of synthetic leather

Sample of	Synthetic leather
		Application example 1	Example 2
Application example 2	Example 8
		Application example 3	Example 16
Application example 4	Example 17
		Application example 5	Example 18
Application example 6	Example 19
		Application example 7	Example 20

Comparative example

Comparative example 1

Comparative example 1 is a commercially available PVC imitation leather.

Comparative example 2

Comparative example 2 was different from example 1 in that 135kg of DMF was added to a stirring vessel, 5kg of paper pulp powder was added thereto, and stirred and mixed uniformly, and then 90kg of polycarbonate polyurethane, 5kg of color paste and 0.6kg of polyether-modified polydimethylsiloxane were sequentially added thereto, and stirred and mixed uniformly to obtain a mixture.

Comparative example 3

Comparative example 3 differs from example 1 in that the polyether modified polydimethylsiloxane was replaced with an equivalent amount of polydimethylsiloxane.

Performance test

(1) And (3) abrasion resistance detection: the synthetic leather in each example is detected according to GB/T2726-2005 'determination of wear resistance of leather physical and mechanical test', a TABER wear resistance tester is utilized to select a grinding wheel of 22H, the weight is loaded by 1000g, the rotation speed is 72 revolutions until the synthetic leather breaks the surface, and the rotation times of the grinding wheel are recorded; the rotation times are the wear-resistant times of the synthetic leather, and the more the wear-resistant times are, the better the wear resistance of the synthetic leather is.

(2) Hand feel test: selecting ten basketball players with ages of 22-25, using basketball in each application example, scoring experience of basketball, scoring for 1-10 points, taking average, and reserving one decimal place after decimal point.

TABLE 3 Performance test results of synthetic leather

Sample of	Number of wear-resistant times
		Example 1	1198
Example 2	1223
		Example 3	1238
Example 4	1089
		Example 5	1212
Example 6	1208
		Example 7	1124
Example 8	1389
		Example 9	1031
Example 10	1346
		Example 11	1355
Example 12	1154
		Example 13	1342
Example 14	1378
		Example 15	1351
Comparative example 1	800
		Comparative example 2	900
Comparative example 3	1023

Table 4 basketball performance test results

Sample of	Hand feel score
		Application example 1	8.9
Application example 2	9.3
		Application example 3	8.6
Application example 4	8.4
		Application example 5	9.0
Application example 6	9.1
		Application example 7	8.2

In combination with table 3, example 1 and comparative example 1, the number of abrasion resistance times of the synthetic leather in example 1 was much greater than that of comparative example 1, so that the abrasion resistance of the synthetic leather in example 1 was better, and it was seen that the abrasion resistance of the synthetic leather prepared in the present application was better.

In combination with table 3, example 1 and comparative example 2, the synthetic leather in example 1 has far greater wear resistance than that of comparative example 2, so that the synthetic leather in example 1 has better wear resistance, and it can be seen that when the wear-resistant foamed PU layer 2 is prepared, the silane coupling agent is added, so that the pulp powder is combined with the polycarbonate polyurethane, and the wear resistance of the prepared synthetic leather is improved.

In combination with table 3, example 1 and comparative example 3, the number of wear-resistant times of the synthetic leather in example 1 is far greater than that of comparative example 3, so that the synthetic leather in example 1 has better wear-resistant performance, and it can be seen that when the wear-resistant foamed PU layer 2 is prepared, the polyether modified polydimethylsiloxane has a leveling effect, and the compatibility of raw materials of the wear-resistant foamed PU layer 2 can be improved, so that the raw materials of the wear-resistant foamed PU layer 2 are mixed more uniformly, and the wear-resistant performance of the prepared synthetic leather is improved.

By combining table 3 with examples 1 to 3, the wear-resistant times of examples 1 to 3 are not greatly changed, and it can be seen that increasing the amount of raw materials of the wear-resistant foamed PU layer 2 during the preparation of the wear-resistant foamed PU layer 2 has little influence on the wear-resistant performance of the prepared synthetic leather.

In combination with table 3, example 2 and examples 4 to 7, the synthetic leather in example 2 has the greatest number of abrasion resistance, so that the synthetic leather in example 2 has better abrasion resistance, and the synthetic leather in example 2, example 5 and example 6 has higher number of abrasion resistance, so that when the weight ratio of pulp powder to polycarbonate polyurethane is 1: and (12-13), the prepared synthetic leather has good wear resistance.

By combining table 3, example 2 and example 8, the synthetic leather in example 8 has a higher wear resistance than that of example 2, and the synthetic leather in example 8 has better wear resistance, and the addition of quartz sand in the preparation of the wear-resistant foamed PU layer 2 improves the wear resistance of the prepared synthetic leather; in combination with table 4, application example 1 and application example 2, the basketball in application example 2 has higher hand feeling score, and it can be seen that when the wear-resistant foaming PU layer 2 is prepared, the addition of quartz sand can not only improve the wear resistance of the prepared synthetic leather, but also improve the anti-skid property of the prepared synthetic leather, thereby improving the hand feeling of the prepared basketball.

By combining table 3 with examples 8-12, the synthetic leather in examples 8, 10 and 11 has more wear-resistant times, and it can be seen that when the wear-resistant foaming PU layer 2 is prepared, the optimal time for the base cloth layer 1 to react in water is 15-25 min, so that the reaction is sufficient, and the raw materials on the base cloth layer 1 are not easy to run off, so that the synthetic leather has better wear-resistant performance.

By combining table 3, example 8 and examples 13 to 15, the wear-resistant times of the synthetic leather in examples 8 and examples 13 to 15 are not greatly changed, and it is seen that the selected base cloth layer 1 has little influence on the wear-resistant performance of the synthetic leather when the synthetic leather is prepared.

In combination with table 4, application example 2 and application example 3, the basketball in application example 2 has a higher hand feel score, and it can be seen that the use of the anti-slip resin improves the anti-slip performance of the synthetic leather when the antibacterial treatment layer 4 is prepared, thereby improving the hand feel of the basketball.

In combination with table 4, application example 2 and application examples 4-7, the basketball in application example 2, application example 5 and application example 6 has higher hand feeling score, and the polishing effect is best when the abrasive-resistant foaming PU layer 2 is polished by using abrasive paper, and the abrasive paper with 180-220 meshes is selected; the abrasive paper with 180-220 meshes is selected for polishing, so that the polished velvet surface layer 3 formed by polishing has certain roughness and is convenient for grasping basketball, and the hand feeling of the basketball is improved.

The present embodiment is only for explanation of the present application and is not to be construed as limiting the present application, and modifications to the present embodiment, which may not creatively contribute to the present application as required by those skilled in the art after reading the present specification, are all protected by patent laws within the scope of claims of the present application.

Claims

1. The utility model provides a wear-resisting foaming PU layer which characterized in that: the raw materials of the wear-resistant foaming PU layer (2) comprise the following components in parts by weight: 90-110 parts of polycarbonate polyurethane, 0.3-0.7 part of polyether modified polydimethylsiloxane, 0.3-0.7 part of silane coupling agent and 5-10 parts of paper pulp powder; the preparation method of the wear-resistant foaming PU layer (2) comprises the following steps: adding polyether modified polydimethylsiloxane, a silane coupling agent, pulp powder and DMF into polycarbonate polyurethane, and uniformly stirring and mixing to obtain a mixture; and (3) coating the mixture on a base cloth layer (1), then placing the base cloth layer (1) into water containing DMF (dimethyl formamide) for reaction for 15-25 min, and foaming on the base cloth layer (1) to form the wear-resistant foaming PU layer (2).

2. The abrasion resistant foamed PU layer of claim 1, wherein: the weight ratio of the pulp powder to the polycarbonate polyurethane is 1: (12-13).

3. The abrasion resistant foamed PU layer of claim 1, wherein: the raw materials of the wear-resistant foaming PU layer (2) further comprise 1-3 parts by weight of quartz sand.

4. A synthetic leather, characterized in that: the wear-resistant foaming PU layer (2) is arranged on the base cloth layer (1), the wear-resistant foaming PU layer (2) is away from the side wall of the base cloth layer (1), the grinding velvet sensing surface layer (3) is arranged on the side wall of the grinding velvet sensing surface layer (3) away from the wear-resistant foaming PU layer (2), and the antibacterial treatment layer (4) is arranged on the side wall of the grinding velvet sensing surface layer (3).

5. A synthetic leather according to claim 4 wherein: the raw material of the antibacterial treatment layer (4) is a mixture of anti-slip resin and antibacterial mildew inhibitor.

6. A synthetic leather according to claim 4 wherein: the base cloth layer (1) is one of leather base cloth, knitted cloth, woven cloth or non-woven cloth.

7. The preparation method of the synthetic leather is characterized by comprising the following steps of: the method comprises the following steps:

preparing a wear-resistant foaming PU layer (2): the raw materials of the wear-resistant foaming PU layer (2) comprise the following components in parts by weight: 90-110 parts of polycarbonate polyurethane, 0.3-0.7 part of polyether modified polydimethylsiloxane, 0.3-0.7 part of silane coupling agent and 5-10 parts of paper pulp powder; the preparation method of the wear-resistant foaming PU layer (2) comprises the following steps: adding polyether modified polydimethylsiloxane, a silane coupling agent, pulp powder and DMF into polycarbonate polyurethane, and uniformly stirring and mixing to obtain a mixture; coating the mixture on a base cloth layer (1), then placing the base cloth layer (1) into water containing DMF (dimethyl formamide) for reaction for 15-25 min, and foaming on the base cloth layer (1) to form a wear-resistant foaming PU layer (2);

Preparation of the ground velvet surface layer (3): polishing the wear-resistant foaming PU layer (2) to form a polishing velvet surface layer (3);

Shaping; an antibacterial treatment layer (4) is arranged on the ground velvet surface layer (3), so that the synthetic leather is prepared.

8. The method for preparing synthetic leather according to claim 7, wherein: in the preparation step of the grinding velvet sensing surface layer (3), the wear-resistant foaming PU layer (2) is polished by sand paper with the mesh number of 180-220.

9. The method for preparing synthetic leather according to claim 7, wherein: in the molding step, an antibacterial mildew-proof agent is added into the anti-slip resin, the mixture is stirred uniformly to obtain a surface treating agent, and the surface treating agent is coated on the ground velvet surface layer (3) to form an antibacterial treating layer (4), so that the synthetic leather is obtained.