CN116265658A

CN116265658A - Preparation method of precast polyurethane surface layer for paving on sports ground

Info

Publication number: CN116265658A
Application number: CN202111551816.XA
Authority: CN
Inventors: 李宇轩; 李翯冈
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-12-17
Filing date: 2021-12-17
Publication date: 2023-06-20

Abstract

The invention discloses a preparation method of a precast polyurethane surface layer for being paved on a sports ground, which comprises the following steps: providing a circulating conveyor belt, wherein a circulating bearing surface which circulates from the front end to the rear end and continuously conveys the belt is arranged on the circulating conveyor belt; a continuous soft mold is arranged on the circulating bearing surface, and a plurality of granular grooves with different depths are uniformly distributed on the surface of the soft mold; continuously and uniformly coating the soft mold with a viscous polyurethane material from the front end of the circulating conveyor belt to form a strip belt with a precast polyurethane surface layer with uniform thickness and width and a slip-resistant granular surface; the bales are then formed for delivery to the field for laying on the playing surface, thereby simplifying the process and reducing the cost of manufacture to complete a precast polyurethane skin having a slip-resistant granular surface.

Description

Preparation method of precast polyurethane surface layer for paving on sports ground

Technical Field

The invention relates to a preparation method of a precast polyurethane surface layer for being paved on a sports ground, in particular to a preparation method of a precast polyurethane surface layer with a slip-resistant granular surface by utilizing a circulating conveyor belt and a preset granular groove on the surface of a soft mold for integral molding.

Background

In the field of preparation methods of polyurethane surface layers of sports fields, the prior art has the defects of easy generation of quality defects such as uneven stirring, uneven elasticity caused by uneven thickness, easy influence of weather, and the like, or the defects of poor weather resistance, easy deterioration of surface physical properties, easy damage by needle shoes, or the like caused by rubber surface skin, or the defects of incapability of continuous production due to the need of additionally arranging a long-strip-shaped giant mold. The applicant applied for and approved the patent technology of Chinese certificate number 3366009 (patent number ZL 201510190515.7) and taiwan invention patent I565854, and the patent technology can make the application of the polyurethane surface layer of the sports ground achieve the effects of quick construction, cost reduction and economic benefit compliance, and can effectively solve the problems of the prior art.

However, the above-mentioned patent technology still has the problem that the surface layer particles (or track particles) of the polyurethane surface layer are easy to fall off, and a "(c-1) step (please refer to the technical content of the above-mentioned patent) is added in the process before the continuous PU layer is heated and cured, and a surface powder particle laying operation is further included to uniformly lay one or a combination of PU powder, PU particles, rubber powder and rubber particles on the surface of the continuous PU layer, thereby forming a surface layer structure of raised anti-slip particles on the surface of the continuous PU layer, so that the problem of relatively increased material cost is generated. Therefore, the applicant proposes an effective improvement for the above-mentioned patent technology.

Disclosure of Invention

The invention provides a preparation method of a precast polyurethane surface layer for being paved on a sports ground, which is characterized in that a continuous soft mold is arranged on a circulating bearing surface of a circulating conveyor belt, a plurality of granular grooves with different depths are uniformly distributed on the surface of the soft mold, and a viscous polyurethane material is continuously and uniformly coated on the soft mold from the front end of the circulating conveyor belt, so that a strip belt with uniform width and uniform thickness and a polyurethane surface layer with a slip-stopping granular surface is formed by the granular grooves arranged on the surface of the soft mold for being paved on the sports ground, thereby effectively solving the problems of the prior art.

To achieve the above object, the present invention provides a method for preparing a precast polyurethane surface layer for paving on a sports ground, comprising the steps of: providing a circulating conveyor belt, wherein a circulating bearing surface which circulates from the front end to the rear end and is continuously conveyed is arranged on the circulating conveyor belt, and at least one heating solidification area is arranged in the continuous conveying process from the front end to the rear end; providing a continuous soft mold and arranging the soft mold on the circulating bearing surface of the circulating conveyor belt, wherein a plurality of granular grooves with different depths are uniformly distributed on the surface of the soft mold; continuously and uniformly coating a viscous Polyurethane (Polyurethane) material on the soft mold from the front end of the circulating conveyor belt, so as to form a continuous strip belt of a precast Polyurethane surface layer with uniform width and uniform thickness on the surface of the soft mold, wherein one surface of the Polyurethane surface layer is provided with a slip-resistant granular surface by virtue of the granular groove arranged on the surface of the soft mold, and the use effect of surface layer particles or runway particles is equivalent; and then the strip formed by the polyurethane surface layer is sent out from the rear end of the circulating conveyor belt, thereby completing the precast polyurethane surface layer with the anti-slip granular surface for being paved on the sports ground.

In a preferred embodiment of the invention, the strip of polyurethane skin is wound into a bundle of rolls each having a length as the strip of pre-cast polyurethane skin is fed out from the rear end of the endless conveyor.

In a preferred embodiment of the present invention, the width of the long strip of polyurethane skin is 1.25m for a standard single track and field runway.

In a preferred embodiment of the present invention, the viscous polyurethane material is formed by mixing liquid Isocyanate or polyisocyanate (Isocyanate) with liquid Polyol or Polyol (Polyol).

In a preferred embodiment of the present invention, the viscous polyurethane material uses an extender with a mixing ratio of 0% to 50% and a plasticizer with a mixing ratio of 0% to 30%.

In a preferred embodiment of the present invention, the viscous polyurethane material has a hardness of 20 ° to 70 ° a after heat curing.

In a preferred embodiment of the invention, the flexible mold is of a length such that when the flexible mold is fed out from the rear end of the endless conveyor, the flexible mold can be rolled into a bundle or rolled together with the strip of polyurethane skin without parting for re-separation during subsequent operations.

In a preferred embodiment of the invention, the flexible mold can be integrated with the endless conveyor to be transported in a synchronous endless manner, or can be placed on a section of the endless conveyor without being integrated.

In a preferred embodiment of the present invention, the flexible mold is made of Silicone, polyvinyl chloride (Polyvinyl Chloride), polypropylene (Polypropylene), polyethylene (Polyethylene), ethylene/vinyl acetate copolymer (Ethylene Vinyl Acetate), ethylene propylene Rubber (EPDM), rubber (Rubber), synthetic Rubber (Synthetic Rubber), or Polyethylene terephthalate (Polyethylene terephthalate).

In a preferred embodiment of the present invention, two side edges of the flexible mold are each provided with an upwardly protruding baffle for stopping the viscous Polyurethane (Polyurethane) material and thereby defining the width or thickness of the Polyurethane skin or strip after molding.

In a preferred embodiment of the present invention, two sides of the endless conveyor are each provided with an upwardly protruding baffle for stopping the viscous Polyurethane (Polyurethane) and thereby defining the width or thickness of the Polyurethane skin or strip after molding.

In a preferred embodiment of the present invention, it further comprises at least one base layer forming step for further forming at least one base layer having a uniform thickness on the opposite side of the slip-resistant granular surface of the polyurethane skin layer in the process, wherein each of the base layers is formed by using a viscous base layer material selected from the group consisting of polyurethane materials other than (and preferably less expensive), whereby the polyurethane skin layer originally having the slip-resistant granular surface can further comprise at least one layer of each of the base layers formed of the viscous base layer material to form a composite polyurethane skin layer.

In a preferred embodiment of the present invention, it further comprises at least one base layer forming step, wherein each of the base layers is formed using a viscous base layer material selected from materials other than polyurethane materials (and preferably less expensive) and preformed into a long strip and wound into a bundle; wherein each base layer is adhered to the strip of the polyurethane surface layer in a pasting manner to form a continuous strip, so that the polyurethane surface layer with the anti-slip granular surface can further comprise at least one layer of each base layer formed by the sticky base layer material to form a composite polyurethane surface layer.

In a preferred embodiment of the present invention, when the polyurethane skin is a composite polyurethane skin, the thickness of the polyurethane skin having the slip-resistant granular surface therein is 1 to 3mm; wherein each of the base layers has a thickness of 3 to 13mm.

In a preferred embodiment of the present invention, a release film is further disposed on the surface of the flexible mold to enable easy separation between the flexible mold and the polyurethane skin for subsequent operations.

Drawings

FIG. 1 is a schematic plan view of an embodiment of the preparation method of the present invention.

FIG. 2 is a schematic perspective view of the strip of FIG. 1 (with a baffle on each side of the endless belt) made of a polyurethane skin having a slip-resistant granular surface.

Fig. 3 is a schematic plan view of another embodiment of the preparation method of the present invention.

FIG. 4 is a schematic perspective view of the continuous strip of polyurethane skin of FIG. 3 (with a baffle on each side of the flexible mold) formed with a slip-resistant granular surface.

FIG. 5 is a schematic side plan view of an embodiment of a polyurethane skin made in accordance with the present invention.

FIG. 6 is a schematic side plan view of an embodiment of a composite polyurethane skin made in accordance with the present invention.

Fig. 7 is an enlarged plan sectional view of a portion of the soft mold of the present invention.

FIG. 8 is a schematic plan view of another embodiment of the invention (the flexible mold and the strip of polyurethane skin remain unbroken and are rolled together into a bundle).

FIG. 9 is a schematic plan view of another embodiment of the present invention for making a composite polyurethane skin.

FIG. 10 is a schematic plan view of a composite polyurethane skin of the present invention.

FIG. 11 is a schematic front plan view of the polyurethane skin of FIG. 2 or FIG. 4 (both sides of the endless belt or flexible mold) with a raised baffle.

FIG. 12 is a schematic front plan view of the composite polyurethane skin of FIG. 11.

Symbol description:

10-circulation conveyer belt

11-circulation bearing surface

12-front end

13-rear end

14-baffle

20-heating curing zone

30-soft mould

31-granular tank

32-baffle

40-viscous polyurethane material

40 a-polyurethane skin layer

40 b-strip

40 c-bundle roll

41-anti-slip granular surface

50-Release film

60-viscous base layer material

60 a-base layer

70-composite polyurethane surface layer

Detailed Description

The following detailed description of the structure and technical features of the present invention is provided with reference to the accompanying drawings, wherein the drawings are for illustrating the structural relationships and related functions of the present invention, and therefore, the dimensions of the components in the drawings are not drawn to actual scale and are not meant to limit the present invention.

Referring to fig. 1 to 4, the present invention provides a method for preparing a pre-cast polyurethane surface layer for paving on a sports ground, wherein the manufacturing end can accelerate the manufacturing of the polyurethane surface layer for finishing the sports ground or the subsequent field construction, and still conform to the elasticity and the surface anti-slip roughness specified by the international track and field union on the track and field runway, and the method mainly comprises the following steps:

(a) There is provided a endless conveyor belt 10, the endless conveyor belt 10 having an endless carrying surface 11 which circulates and is continuously conveyed from a front end 12 to a rear end 13 thereof, and at least one heat curing zone 20 being provided during the continuous conveyance from the front end 12 to the rear end 13, as shown in fig. 1 and 3. Since the structure of each heat curing zone 20 or the control technique thereof, such as temperature control and time control, can be achieved by the prior art, the present invention is not limited to the above-mentioned embodiments, and will not be described herein.

(b) Providing a continuous soft mold 30 and being arranged on the circulating bearing surface 11 of the circulating conveyor belt 10, wherein a plurality of granular grooves 31 with different depths are uniformly distributed on the surface of the soft mold 30, as shown in fig. 7; wherein the soft mold 30 is made of, but not limited to, silicone (Silicone), polyvinyl chloride (Polyvinyl Chloride), polypropylene (Polypropylene), polyethylene (Polyethylene), ethylene/vinyl acetate copolymer (Ethylene Vinyl Acetate), ethylene propylene Rubber (EPDM), rubber (Rubber), synthetic Rubber (Synthetic Rubber), or Polyethylene terephthalate (Polyethylene terephthalate).

(c) Providing a viscous Polyurethane (Polyurethane) material 40; the viscous polyurethane material 40 is formed by mixing liquid Isocyanate or polyisocyanate (Isocyanate) with liquid Polyol or Polyol (Polyol), but is not limited thereto; wherein the viscous polyurethane material 40 uses an additive with a mixing ratio of 0% to 50% and a plasticizer with a mixing ratio of 0% to 30%, but is not limited thereto. Since the composition technology of the viscous polyurethane material 40 is the prior art in the chemical industry and can be achieved by the prior art in the field, and is not the focus of the present invention, the description thereof is omitted herein.

(d) The viscous polyurethane material 40 is continuously and uniformly coated on the surface of the flexible mold 30 from the front end 12 of the endless conveyor 10, so that the viscous polyurethane material 40 can integrally form a continuous strip 40b of pre-cast polyurethane surface 40a (shown in fig. 5) with a slip-preventing granular surface 41 and uniform thickness and width on the surface of the flexible mold 30, as shown in fig. 1 to 4, wherein one surface of the polyurethane surface 40a (i.e. the bottom surface of the polyurethane surface 40a as shown in fig. 1 to 4) integrally forms the slip-preventing granular surface 41 (shown in fig. 5) on the polyurethane surface 40a by the granular grooves 31 provided on the surface of the flexible mold 30, and the slip-preventing granular surface 41 is equivalent to the polyurethane surface 40a having the structural form and use efficacy of surface particles or runway particles.

(e) The strip 40b formed from the polyurethane skin 40a is fed out of the rear end 13 of the endless conveyor 10, completing a pre-cast polyurethane skin (i.e., the polyurethane skin 40 a) having a slip-resistant granular surface 41, as shown in fig. 5.

The polyurethane skin 40a (shown in fig. 5) formed by the viscous polyurethane material 40 after heat curing has a hardness of 20 ° to 70 ° a, but is not limited thereto.

Referring to fig. 1 to 4, in step (e), when the strip 40b of the polyurethane skin 40a is fed out from the rear end 13 of the endless conveyor belt 10, the strip 40b of the polyurethane skin 40a is wound into a bundle 40c, and each bundle 40c has a length to facilitate storage, warehousing or handling of the polyurethane skin 40a (i.e., the strip 40 b).

Referring to fig. 3, 4 and 11, two sides of the soft mold 30 are provided with a baffle 32 protruding upwards, each baffle 32 is used as or to define a side edge surface of the polyurethane skin 40a or the long strip 40b formed by the baffle, so as to smoothly produce the polyurethane skin 40a or the long strip 40b with equal thickness and equal width.

Referring to fig. 1, 2 and 11, two sides of the endless conveyor belt 10 are provided with a baffle 14 protruding upward, each baffle 14 is used as or to define a side edge surface of the polyurethane skin 40a or the strip 40b formed therefrom during molding, so as to smoothly produce the polyurethane skin 40a or the strip 40b having a uniform thickness and a uniform width.

In addition, the width of the polyurethane skin 40a or the strip 40b may be designed to be, but not limited to, 1.25m for a standard single track and field runway.

Referring to fig. 1, the present invention further provides a release film 50 on the surface of the flexible mold 30, but not limited thereto, wherein the release film 50 may be disposed at the outer portion of the front end 12 of the endless conveyor 10 by a release film bundle roll (not shown) so that the release film 50 can be continuously provided by the release film bundle roll to enter from the front end 12 of the endless conveyor 10 and be laid on the surface of the flexible mold 30, so that the release film 50 can be synchronously conveyed and moved along with the endless bearing surface 11 (see left in fig. 1), thereby enabling the viscous polyurethane material 40 coated on the surface of the flexible mold 30 to be coated on the release film 50. When the polyurethane skin 40a or the strip 40b is fed or rewound from the rear end 13 of the endless conveyor belt 10 into a bundle 40c (right side of fig. 1), the release film 50 can also be rolled up (not shown) along with the polyurethane skin 40a or the strip 40b, so as to facilitate the maintenance of a non-tacky state in which the polyurethane skin 40a adjacent to the bundle 40c can be easily separated.

The preparation method of the precast polyurethane surface layer of the invention is further provided with the following examples, which respectively illustrate the following steps:

referring to the embodiment shown in fig. 1, 3, 6 and 12, between step (d) and step (e), at least one base layer pre-casting step is further included to form at least one base layer 60a (as shown in fig. 6), each base layer 60a (as shown in fig. 6) being formed by pre-casting each base layer 60a (as shown in fig. 6) of one layer on the opposite side of the slip-resistant granular surface 41 of the polyurethane skin 40a to form a composite polyurethane skin 70 or a continuous long strip of the composite polyurethane skin 70, as shown in fig. 1, 3 and 6. Each of the base layers 60a is formed by using the viscous base layer material 60 selected from the group consisting of the viscous polyurethane materials 40, and the viscous base layer material 60 is continuously and uniformly coated on the opposite sides of the slip-resistant granular surface 41 of the polyurethane surface layer 40a, so that the viscous base layer material 60 can form at least one more base layer 60a (as shown in fig. 6) having a uniform thickness and width on the surface of the polyurethane surface layer 40a (or the strip 40 b), thereby enabling the manufactured composite polyurethane surface layer 70 (as shown in fig. 6) to be changed to include the thickness of one layer of the polyurethane surface layer 40a having the slip-resistant granular surface 41 and the thickness of one layer of the base layer 60a, as shown in fig. 6, that is, the polyurethane surface layer 40a preformed by the viscous polyurethane material 40 in step (d) of the original embodiment or the strip 40b formed by the same as the thin layer structure of the thin layer structure having the slip-resistant granular surface 41 is changed, that the thin layer 40a is formed by the thin layer of the thin layer structure of the polyurethane material 40a (as shown in fig. 6) on the opposite sides of the other layer 60a, and the thin layer of the thin layer 40b is formed by the thin layer of the opposite layer structure of the polyurethane layer 60a as shown in the opposite side of the layer 60a. In addition, the thickness of the polyurethane surface layer 40a is 1 to 3mm, but not limited thereto, and the thickness of each of the base layers 60a is 3 to 13mm, but not limited thereto.

Referring to the embodiment shown in fig. 6, 9 and 10, between the step (d) and the step (e), further comprising a pre-casting step of at least one base layer to form at least one base layer 60a (as shown in fig. 6), wherein each base layer 60a is formed by using the viscous base layer 60 selected from materials other than polyurethane, wherein each base layer 60a is preformed into a long strip body and rolled into a bundle, as shown in fig. 9; wherein each of the base layers 60a is adhesively bonded to the polyurethane skin 40a having the slip-resistant granular surface 41 to form a continuous strip of the composite polyurethane skin 70 in the process, as shown in fig. 6, 9 and 10, wherein the thickness of the composite polyurethane skin 70 is equal to the thickness of the polyurethane skin 40a plus the thickness of each of the base layers 60a. In addition, the thickness of the polyurethane surface layer 40a is 1 to 3mm, but not limited thereto, and the thickness of each of the base layers 60a is 3 to 13mm, but not limited thereto.

In the embodiment shown in fig. 1 and 2, the continuous flexible mold 30 is of a certain length; wherein in step (e), the flexible mold 30 is rolled into a bundle of rolls while the flexible mold 30 is being fed out from the rear end 13 of the endless conveyor 10, but is not limited thereto, to facilitate storage, warehousing or handling of the flexible mold 30.

In the embodiment shown in fig. 8, the flexible mold 30 is of a certain length; wherein in step (e), when the flexible mold 30 is sent out from the rear end 13 of the endless conveyor belt 10, the flexible mold 30 is shipped together with the continuous strip 40b of the polyurethane surface layer 40a, but not limited thereto (or alternatively, not rolled), and the strip 40b is released from the flexible mold 30 for construction operation after the related construction of the sports ground, so as to facilitate the increased protection of the strip 40 b; wherein the flexible mold 30 is placed only in one process but is not located on the endless conveyor 10 in conjunction with the endless conveyor 10, but is not limited thereto.

In the embodiment shown in fig. 3 and 4, the flexible mold 30 is integral with the endless conveyor 10, but is not limited to, to facilitate continuous production of the strip 40b without interruption (unless an interrupt operation is manually or programmatically set).

In addition, the manufactured anti-slip granular surface 41 (rolled into a bundle) and the base layers 60a (rolled into a bundle) can be separately carried to the construction site by the manufacturer or manufacturer for being combined, as shown in fig. 10, so that the easy transportation and the easy construction are facilitated.

The above-manufactured slip-resistant granular surface 41 (rolled into a bundle) is realized by exclusively manufacturing the long strip 40b having the slip-resistant granular surface 41 (i.e., the polyurethane skin 40 a).

Compared with the prior art, the preparation method of the precast polyurethane surface layer for being paved on the sports ground has the following advantages:

(1) The soft mold 30 of the present invention has a plurality of granular grooves 31 with different depths, so that the continuous strip 40b of the polyurethane surface layer 40a with the anti-slip granular surface 41 and uniform thickness and uniform width can be produced, thereby effectively solving the problem that the surface layer particles (i.e. runway particles) of the polyurethane surface layer are easy to fall off in the prior art.

(2) The composite polyurethane surface layer 70 of the present invention is composed of a polyurethane surface layer 40a having a slip-resistant granular surface 41 and a layer of each of the base layers 60a, and the need of spraying runway particles on each of the base layers 60a is eliminated as in the prior art, which is helpful for reducing the construction time of the sports ground, accelerating the completion of the construction, and reducing the construction cost.

The foregoing description of the preferred embodiments of the present invention is merely illustrative, and not restrictive, of the invention. It will be appreciated by those skilled in the art that many changes, modifications and even equivalent changes may be made thereto without departing from the spirit and scope of the invention as defined in the appended claims, but are to be accorded the true scope of the invention.

Claims

1. A method for preparing a pre-cast polyurethane surface layer for paving in a sports field, comprising the steps of:

(a) Providing a circulating conveyor belt, wherein the circulating conveyor belt is provided with a circulating bearing surface which circulates from the front end to the rear end and continuously conveys the circulating bearing surface, and at least one heating and solidifying area is arranged in the continuous conveying process from the front end to the rear end;

(b) Providing a continuous soft mold and arranging the soft mold on the circulating bearing surface of the circulating conveyor belt, wherein a plurality of granular grooves with different depths are uniformly distributed on the surface of the soft mold;

(c) Providing a viscous polyurethane material;

(d) Continuously and uniformly coating the viscous polyurethane material on the soft mold from the front end of the circulating conveyor belt, so as to form a continuous strip belt of a precast polyurethane surface layer with uniform width and uniform thickness on the surface of the soft mold, wherein one surface of the polyurethane surface layer is integrally formed with a slip-resistant granular surface by virtue of the granular groove arranged on the surface of the soft mold; a kind of electronic device with high-pressure air-conditioning system

(e) The strip formed by the polyurethane surface layer is sent out from the rear end of the circulating conveyor belt, thereby completing a precast polyurethane surface layer with a slip-resistant granular surface for being paved on a sport field.

2. The method of preparing a pre-cast polyurethane skin according to claim 1, wherein in step (e), said strip of polyurethane skin is wound into a bundle of rolls each having a length as said strip of pre-cast polyurethane skin is fed out at a rear end of said endless conveyor.

3. The method of preparing a pre-cast polyurethane skin according to claim 2, wherein the width of said long strip of polyurethane skin is 1.25m for a standard single track and field runway.

4. The method of claim 1, wherein the viscous polyurethane material is formed by mixing liquid isocyanate or polyisocyanate and liquid polyol or polyol.

5. The method of preparing a pre-cast polyurethane skin according to claim 1, wherein the viscous polyurethane material uses an extender with a mixing ratio of 0% to 50% and a plasticizer with a mixing ratio of 0% to 30%.

6. The method of producing a pre-cast polyurethane skin according to claim 1, wherein the viscous polyurethane material has a hardness of 20 ° to 70 ° a after heat curing.

7. The method of preparing a pre-cast polyurethane skin according to claim 1, wherein said flexible mold has a certain length; wherein in step (e) the flexible mold can be rolled into a bundle of rolls as it is fed out from the rear end of the endless conveyor or rolled into a bundle of rolls together with the strip of polyurethane skin without being released from the form.

8. The method of claim 1, wherein the flexible mold is capable of being combined with the endless conveyor to be transported in a synchronous circulation or is placed on a section of the endless conveyor without being combined.

9. The method of preparing a pre-cast polyurethane skin according to claim 1, wherein the flexible mold is made of silicone, polyvinyl chloride, polypropylene, polyethylene, ethylene/vinyl acetate copolymer, ethylene propylene rubber, synthetic rubber, or polyethylene terephthalate.

10. The method according to claim 1, wherein each of the two sides of the flexible mold is provided with an upwardly protruding baffle for stopping the viscous polyurethane material, and thereby defining the width or thickness of the polyurethane skin or the strip after molding.

11. The method of claim 1, wherein each of the two sides of the endless conveyor is provided with an upwardly protruding baffle for stopping the viscous polyurethane material and thereby defining the width or thickness of the polyurethane skin or strip after molding.

12. The method of claim 1, further comprising at least one base layer forming step between step (d) and step (e) for further forming at least one base layer having a uniform thickness on the opposite side of the slip-resistant granular surface of the polyurethane skin layer during the manufacturing process, wherein each of the base layers is formed using a viscous base layer material other than polyurethane material, whereby the polyurethane skin layer originally having the slip-resistant granular surface can further comprise at least one layer of each of the base layers formed of the viscous base layer material to form a composite polyurethane skin layer.

13. The method of claim 1, further comprising at least one base layer forming step between step (d) and step (e), wherein each base layer is formed using a viscous base layer material selected from materials other than polyurethane materials and preformed into a long strip and wound into a bundle; wherein each base layer is adhered to the strip of the polyurethane surface layer in a pasting manner to form a continuous strip, so that the polyurethane surface layer with the anti-slip granular surface can further comprise at least one layer of each base layer formed by the sticky base layer material to form a composite polyurethane surface layer.

14. The method for producing a pre-cast polyurethane skin according to claim 12 or 13, wherein when the polyurethane skin is a composite polyurethane skin, the thickness of the polyurethane skin having the slip-resistant granular surface is 1 to 3mm; wherein each of the base layers has a thickness of 3 to 13mm.

15. The method of claim 1, wherein a release film is further provided on the surface of the flexible mold to facilitate separation between the flexible mold and the polyurethane skin layer before step (c).