GB2538488A

GB2538488A - Cricket ball cover manufacturing method

Info

Publication number: GB2538488A
Application number: GB1507826.4A
Authority: GB
Inventors: Chen Shyi-Ming
Original assignee: Individual
Current assignee: Individual
Priority date: 2015-04-28
Filing date: 2015-05-07
Publication date: 2016-11-23
Anticipated expiration: 2035-05-07
Also published as: GB2538488B; GB201507826D0; GB201507209D0

Abstract

A cricket ball cover manufacturing method, comprising following steps: forming a ball core 210 ; placing a fiber layer consisting of two figure-8 shaped fiberlayer pieces around ball core 220; winding fiber layer with fine threads, then infusing liquid Polyurethane material into the fiber layer 230; attaching and aligning a masking jig piece onto inner side of ball cover mold piece to expose the stitch-shaped grooves while covering rest of the inner side 240; applying coloring material on the masking jig piece, filling stitch-shaped grooves 250; removing the masking jig piece from the ball cover mold 260; placing the ball core and the ball cover into a metal mold holder 270; heating up ball cover mold and metal mold holder, to cure them at 70°C for 3 hours 280. The ball may have a core comprising cork, which is layered and tightly bound with strings.

Description

CRICKET BALL COVER MANUFACTURING METHOD

BACKGROUND OF THE INVENTION FIELD OF THE INVENTION

The present invention relates to a ball cover manufacturing method, and in particular to a cricket ball cover manufacturing method.

THE PRIOR ARTS

Cricket balls are played mostly in member countries of the British Commonwealth, mainly the United Kingdom, Australia, New Zealand, India, Pakistan, South Africa and West Indies, among others.

The cricket ball is composed of a core and a cover. The core is made of cork, which is layered and tightly wound with strings, before it is encased with a leather cover. The cover of the cricket ball can be made either of two hemispherical pieces of leather being sewn together, or of four quartered pieces with two quartered pieces formed together into one hemispherical piece first, then the two hemispherical pieces being sewn together to a slightly raised seam. Conventionally, a cricket ball cover is dyed in red color and polished to give a shining appearance.

Refer to Figs. 1(a) to 1 (c) respectively for a front view, a side view, and seam stitches of a conventional cricket ball according to the Prior Art. As shown in Figs. 1(a) and 1(b), six rows of stitches are formed along the -equator" of the cricket ball 10.

Wherein, the outer four rows of decorative stitches 112 are machine-stitched, while the inner two rows of seam stitches 111 are interlocked and hand-stitched to bind the two hemispherical pieces together. Since the conventional cover is made of leather having a high degree of hardness, therefore the outer four rows of decorative stitches 112 are made by a special sewing machine. Further, the inner two rows of seam stitches 111 on the ball "equator" are made first through punching two rows of holes by a hole drilling machine. Then, stitches are made manually by applying two needles with threads thereon through the punched holes, to seam in an interlocking pattern the two hemispheric leather pieces together, to form a complete cricket ball cover.

In the prior art, the inner two rows of interlocked stitches on the ball "equator" are made manually, while each row having about 80 holes to stitch, for a total of 160 holes for the entire ball cover, and that is quite time-consuming and tedious. Refer to Fig. 1(c) for a schematic diagram of ways of performing interlocked stitching for binding two hemispherical leather ball cover pieces together into a ball cover according to the Prior Art. As shown in Fig. 1(c), 16 punched holes for interlocked stitches are taken as an example for easy explanation and understanding. Firstly (step 1), a needle with a thread attached thereon is pushed down the leather through hole 1, then it is interlocked to hole 10 through and underneath the leather. Next (step 2), the needle is pushed from under the hole 10 up to the surface of the leather, and it is advanced forward to hole 11, to be pushed down from hole 11, and it is interlocked through and underneath the leather to hole 3. Then (step 3), the needle is pushed from under the hole 3 up to the surface of the leather, and it is advanced forward to hole 4, to be pushed down from hole 4, and it is interlocked through and underneath the leather to hole 12. Subsequently (step 4), the steps 2 and 3 above are repeated until the needle and thread reaches hole 8. And then (step 5), the needle and thread is interlocked through and underneath the leather to hole 16, and since the ball is of a round shape, the needle is then advanced to hole 9, and interlocked to hole 1, and then is advanced to hole 2. Similarly, for the corresponding part of the seam stitches mentioned above, a needle with a thread attached thereon is pushed down from the leather through hole 9, to perform steps similar to the steps 1 to 5 described above, until the needle reaches hole 16, then it is interlocked to hole 8, and it is advanced to hole 1, to complete the seam stitching of the cricket ball cover.

The manual stitching mentioned above requires lots of time and effort and consumes great strength, as such its productivity is low and its efficiency is lacking.

In addition, in this way of making cricket ball cover, the 4 outer rows of decorative stitches and the 2 inner rows of interlocked seam stitches are made in two different and separate steps after the two hemispherical pieces are made, thus the labor cost is high and it is not cost efficient.

Therefore, the shortcomings of this type of cricket ball are that, (1). the ball cover is made of genuine leather, its price is pretty high, so it is rather difficult to reduce the production cost; (2). the interlocked stitches between two adjoining hemispherical pieces have to be stitched manually, even for a skilled worker, the output of stitched balls per day is quite limited, thereby raising the production cost and slowing down the production speed; (3). water and moisture tend to seep into the ball core through the seams between the stitches, to cause the ball to gain weight, to become swollen, loosened and deformed, to affect the hardness and performance of the cricket ball.

Therefore, presently, the design and production of the cricket ball cover still leave much to be desired, and it has much room for improvement.

SUMMARY OF THE INVENTION

The present invention seeks to provide an improved cricket ball cover manufacturing method.

Aspects of the present invention are defined in the appended claims.

According to an aspect of the present invention there is provided a cricket ball cover manufacturing method including the following steps: 1. Forming a ball core made of cork, which is layered and tightly wound with strings.

2. Placing and gluing a fiber layer consisting of two figure-8 shaped fiber layer pieces serving as a base of a consistent thickness around the ball core.

3. Winding on the ball core having the fiber layer thereon with a proper amount of fine thread to hold the two figure-8 shaped fiber layer pieces on to the ball core, then infusing a liquid Polyurethane (PU) material into and impregnating the fiber layer. The liquid Polyurethane can be pigmented either in red, white, pink, optic orange or other specific colors.

4. Attaching and aligning a masking jig piece onto an inner side of a ball cover mold piece having multiple stitch-shaped grooves, with the masking jig piece having notches configured to expose the stitch-shaped grooves on the inner side of the ball cover mold piece, while covering the rest of the inner side of the ball cover mold piece.

5. Using hands to apply or using a spraying tool to spray a coloring material on the masking jig piece, to fill the coloring material in the stitch-shaped grooves of the ball cover mold piece, with the rest of the inner side of the ball cover mold piece shielded by the masking jig piece.

6. Removing the masking jig piece from the ball cover mold piece.

7. Placing the Polyurethane-soaked ball core inside the ball cover mold, and then putting the ball cover mold encased with the PU-soaked ball core into a metal mold holder for the ball core to tightly engage with the ball cover mold.

8. Heating up the ball cover mold and metal mold holder,and curing the ball core and ball cover inside at approximately 70°C for 3 hours.

9. Removing a finished ball having two inner rows of slightly bulged seam stitches and four outer rows of slightly bulged stitches, formed integrally with the coloring material thereon, from the ball cover mold and the metal mold holder.

In the step 1 mentioned above, the ball core is one of any existing regulation cricket ball cores that can be made of cork, which is layered and tightly wound with strings.

In the step 2 mentioned above, the fiber layer serving as a foundation material can be made of pile, felt, natural or synthetic fibers, natural or synthetic yarns, natural non-woven cloth, synthetic non-woven cloth, natural woven cloth, synthetic woven cloth, or a combination of two or more materials mentioned above. Then, a proper amount of the fine thread, such as cotton thread or synthetic thread, is used to wind around the two figure-8 shaped fiber layer pieces to hold them firmly together.

In the step 3 mentioned above, the ball core with the fiber layer glued thereon is infused and impregnated with liquid Polyurethane (PU).

In the step 4 mentioned above, the masking jig having notches configured to expose the stitch-shaped grooves while covering the rest of the inner side of the ball cover mold, is made of metal or plastic.

In the step 5 mentioned above, the coloring material applied or sprayed onto the masking jig can be made of liquid polyurethane (PU) or other applicable dyeing material of a specific color.

Summing up the above, in the present invention, the fiber layer serving as a base is glued to the ball core first; then, it is wound with fine thread and impregnated with liquid Polyurethane pigmented in a specific color, to be bonded firmly onto the surface of the ball core. As such, it is molded integrally onto the ball core to form a ball cover, after t is heated and cured in a ball cover mold. The finished ball cover thus produced is unitary, one-piece, fiber-embedded and of uniform thickness, thereby acquiring the comparable durability strength of a genuine leather ball cover. The ball cover can be made in either red, white, pink, or other specific color through the pigmented Polyurethane liquid. In addition, the ball cover can be made into various elected thicknesses, preferably from 4mm to 6mm, depending on actual requirement by way of adjusting the density and texture of the fiber layer to be embedded.

Further scope of the applicability of the present invention will become apparent from the detailed descriptions given hereinafter. However, it should be understood that the detailed descriptions and specific examples, -hile ndicating preferred embodiments of the present invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the present invention will become apparent to those skilled in the art from this detailed descriptions.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention are described below, by way of example only, with reference to the accompanying drawings, in which: Fig.1(a) is a front view of a conventional cricket ball according to the Prior Art; Fig.1(b) is a side view of a conventional cricket ball according to the Prior Art; Fig. 1(c) is a schematic diagram of ways of performing interlocked stitching for binding two hemispherical leather ball cover pieces together into a ball cover according to the Prior Art; Fig. 2 is a flow chart of a cricket ball cover manufacturing method according to an embodiment of the present invention; Fig. 3(a) is a front view of a cricket ball according to an embodiment of the present invention; Fig. 3(b) is a side view of a cricket ball according to an embodiment of the present invention; Fig. 3(c) is a cross section view of a cricket ball according to an embodiment of the present invention; Fig. 4(a) is a front view of a figure-8 shaped fiber layer piece according to an embodiment of the present invention; Fig. 4(b) is a schematic diagram of two figure-8 shaped fiber layer pieces forming into a fiber layer according to an embodiment of the present invention; Fig. 5(a) is a top side view of a ball cover mold piece having stitch-shaped grooves for the decorative stitches and seam stitches according to an embodiment of the present invention; Fig. 5(b) is a bottom side view of a masking jig having notches corresponding to stitch-shaped grooves of the ball cover mold piece of Fig. 5(a); Fig. 6(a) is a schematic diagram of a ball core having ball cover, two ball cover mold pieces according to an embodiment of the present invention; Fig. 6(b) is a schematic diagram of a ball core having ball cover, two ball cover mold pieces, and a metal mold holder according to an embodiment of the present invention; and Fig. 7 is a cross-sectional view of the metal mold holder in Fig. 6(b), when holding therein the ball core encased in the ball cover mold.

The components of the drawings are not necessarily to scale, emphasis instead being placed upon illustrating the teachings herein.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The purpose, construction, features, functions and advantages of the embodiments of present invention can be appreciated and understood more thoroughly through the following detailed description with reference to the attached drawings.

Refer to Figs. 2 to 7 for detailed descriptions of a cricket ball cover manufacturing method according to an embodiment of the present invention. Firstly, as shown in Fig. 2, the cricket ball cover manufacturing method according to an embodiment of the present invention includes the following steps: 1. Forming a ball core made of cork, which is layered and tightly wound with strings (step 210).

2. Placing and gluing a fiber layer consisting of two figure-8 shaped fiber layer pieces serving as a base of consistent thickness around the ball core (step 220).

3. Winding on the ball core having the fiber layer thereon with a proper amount of fine thread to hold the two figure-8 shaped fiber layer pieces firmly together on the ball core, then infusing a liquid Polyurethane (PU) material into and impregnating the fiber layer (step 230).

4. Attaching and aligning a masking jig piece onto an inner side of a ball cover mold piece having multiple stitch-shaped grooves, with the masking jig piece having notches configured to expose the stitch-shaped grooves on the inner side of the ball cover mold piece while covering the rest of the inner side of the ball cover mold piece (step 240).

5. Using hands to apply or using a spraying tool to spray a coloring material on the masking jig piece, to fill the coloring material in the stitch-shaped grooves of the ball cover mold piece, with the rest of the inner side of the ball cover mold piece shielded by the masking jig piece (step 250).

6. Removing the masking jig piece from the ball cover mold piece (step 260).

7. Placing the Polyurethane-soaked ball core inside the ball cover mold, and then putting the ball cover mold encased with the soaked ball core into a metal mold holder for the ball core to tightly engage with the ball cover mold (step 270).

8. Heating up the ball cover mold and the metal mold holder, and curing the ball core and ball cover inside at approximately 70°C for 3 hours (step 280).

9. Removing a finished ball having two inner rows of slightly bulged seam stitches and four outer rows of slightly bulged decorative stitches, formed integrally with the coloring material thereon, from the ball cover mold and the metal mold holder (step 290).

In the following, the various characteristics of the cricket ball cover of embodiments of the present invention are described in detail.

Firstly, refer to Figs. 3(a), 3(b), and 3(c) respectively for a front view, a side view, and a cross section view of a cricket ball according to an embodiment of the present invention. As shown in Figs. 3(a) to 3(c), the independently formed ball core 1 is one of the conventional ball cores commonly used in a regulation cricket ball, that is made of cork, which is layered and tightly wound with strings. The fiber layer 2 is used as a foundation material, and can be made of pile, felt, natural or synthetic fibers, natural or synthetic yarns, natural non-woven cloth, synthetic non-woven cloth, natural woven cloth, synthetic woven cloth, or a combination of two or more materials mentioned above, either wound or laminated.

The fiber layer 2 is formed by two figure-8 shaped fiber layer pieces 3, matched closely to each other and wrapped around the ball core, to form into a spherical shape at an elected and consistent thickness. It is full of pores and so porous that it can quickly absorb and get fully impregnated with the infused liquid Polyurethane. Then, the two figure-8 shaped fiber layer pieces 3 are wound with a proper amount of fine thread, weighing about 3 to 5 grams, to hold the fiber layer 2 firmly on the ball core 1.

After the subsequent heating and curing processes, the fiber layer 2 gets cured and transformed into finished ball cover 4.

To achieve aesthetical and decoration purpose, and also taking into consideration of the fact that players and spectators are accustomed to the conventional outer appearance of the cricket ball, in the present invention, along each side of the equator of the ball cover 4 are formed one inner row of seam stitches 311 and two outer rows of decorative stitches 312. The stitches are formed automatically using the same material as the ball cover in the heating and curing process, to achieve labor cost and process time savings significantly. The ball cover can be made into red color or white color or other specific color, while the stitches are made into the usual white or light brown color, but the present invention is not limited to this.

In the present invention, all of the 6 rows of stitches alongside the ball "equator" are made in the heating and curing process automatically, without the need of putting needles and threads through the ball cover, yet the features or characteristics of the conventional cricket ball cover are retained in the present invention.

Then, refer to Figs. 4(a) and 4(b) respectively for a front view of a figure-8 shaped fiber layer piece according to an embodiment of the present invention; and a schematic diagram of two figure-8 shaped fiber layer pieces formed into a fiber layer according to an embodiment of the present invention. As shown in Figs. 4(a) and 4(b), the fiber layer pieces 3 are of two figure-8 shaped fiber pieces, and the two of them are formed into a spherical fiber layer 2. In this way, it can avoid the shortcomings of the prior art that wrinkles and folds tend to appear that when a whole sheet of ball cover material is put onto the ball core 1 to cause unevenness of the ball cover 4. Subsequently, refer to Figs. 5(a) and 5(b) respectively for a top side view of a ball cover mold piece having stitch-shaped grooves for decorative stitches and seam stitches according to an embodiment of the present invention; and a bottom side view of a masking jig piece having notches corresponding to stitch shaped grooves of the ball cover mold piece of Fig. 5(a) according to an embodiment of the present invention. In the present invention, the ball cover mold 5 is formed by two flexible plastic matching ball cover mold pieces 51, while the masking jig 6 is formed by two matching masking jig pieces 61.

As shown in Figs. 5(a) and 5(b), in the present invention, a masking jig piece 61 is attached and aligned onto an inner side of a ball cover mold piece 51 having multiple stitch-shaped grooves, with the masking jig piece 61 having notches configured to match and expose said stitch-shaped grooves on said inner side of the ball cover mold piece 51, while covering the rest of the inner side of the ball cover mold piece 51. Next, coloring material is applied or sprayed onto the masking jig piece 61 to fill the coloring material in the stitch-shaped grooves of the ball cover mold piece 51, with the rest of the inner side of the ball cover mold piece 51 shielded by the masking jig piece 61. Then, the masking jig piece 61 is removed from the ball cover mold piece 51.

Finally, refer to Figs. 6(a), 6(b), and 7 respectively for a schematic diagram of a ball core having ball cover, two ball cover mold pieces; a schematic diagram of a ball core having ball cover, two ball cover mold pieces, and a metal mold holder; and a cross-sectional view of the metal mold holder according to an embodiment of the present invention. As shown in Figs. 6(a), 6(b), and 7, the Polyurethane-soaked ball core 1 is placed inside the ball cover mold 5, and then they are put into a metal mold holder 53 for the ball core 1 to tightly engage the ball cover mold 5. Afterwards, the metal mold holder 53 is put into an oven to heat up, and to cure the PU-impregnated fiber layer 2 around the ball core 1 inside the ball cover mold 5 at approximately 70t for 3 hours. Finally, the ball cover mold 5 and the metal mold holder 53 are removed, to reveal a cricket ball having two inner rows of slightly bulged seam stitches and four outer rows of slightly bulged decorative stitches, formed integrally with the coloring material thereon.

In an embodiment of the present invention, the inner row of seam slots 513 and the outer rows of decorative slots 514 in the ball cover mold piece 51 are used to receive the coloring material applied or sprayed through the corresponding inner row of seam notches 613 and outer rows of decorative notches 614 of the masking jig pieces 61. As such, the number of seam slots 513 is equal to that of seam notches 613, while the number of decorative slots 514 is equal to that of the outer rows of decorative notches 614.

In an embodiment of the present invention, seam slots 513 and decorative slots 514 of ball cover mold 5 made of the flexible plastic, polyethylene (PE) in particular, are used to receive coloring material made of Polyurethane (PU). As such, the seam stitches 311 and the decorative stitches 312 formed on the ball cover 4 after heating and curing process can be detached and released easily from the seam slots 513 and the decorative slots 514. Since PU material and PE mold can only form pseudo-molding, without being able to merge or mold into each other, thus they can be separated apart easily The liquid Polyurethane (PU) utilized in the fiber layer, after the curing process, can smooth over all the wrinkles and folds that may otherwise exist on a conventional cricket ball cover, giving it a desired texture and a smooth appearance.

The shape, color, stitches, texture and outer appearance of the cricket ball can be controlled and varied by using different types of ball cover molds.

Also, in an embodiment of the present invention, the fiber layer 2 is formed by two fiber layer pieces 3 with an elected and consistent thickness, regardless of the fiber layer 2 being a single piece, padded, laminated, or wound structure. As such, a finished ball cover 4 of equal thickness can be obtained. For practical purpose, the fiber layer is elected to be of a given thickness ranging from 4 mm to 6 mm. But the present invention is not limited to this.

Moreover, in an embodiment of the present invention, the coloring material of the seam stitches 311 and decorative stitches 312 is liquid Polyurethane (PU) of usual white or light brown color (that is the same material used to make the ball cover, but of different color); while the masking jig is made of metal or plastic.

Further, in an embodiment the present invention, the number of seam slots 513 and the decorative slots 514 in a ball cover mold piece 51 is 65, while the number of corresponding seam notches 613 and decorative notches 614 in the masking jig piece 61 is also 65, but the present invention is not limited to this.

Summing up the above and in conclusion, the advantages of embodiments of the present invention over the Prior Art can be summarized as follows: 1. In embodiments of the present invention, liquid Polyurethane (PU) blended with pile, felt, natural or synthetic fibers, natural or synthetic yarns, natural or synthetic non-woven cloth, natural or synthetic woven cloth are utilized as materials for making ball cover of a cricket ball. The materials thus incorporated are transformed after curing process into a solid, fiber-embedded, one-piece ball cover of uniform thickness, thus, the ball cover s water-proof and air-tight for durable plays. The hardness of the ball cover thereby produced can also be controlled by chemical formulas to vary at different degrees to suit different levels of plays. The ball cover thereby produced can replace the costly genuine leather used in the Prior Art, in achieving material cost savings significantly.

2. In embodiments of the present invention, the decorative stitches, the seam stitches and ball cover coloring are made integrally with the ball cover automatically and simultaneously in the heating and curing process, without the need to put needle and thread stitch-by-stitch through the genuine ball cover for about 160 stitches as done in the Prior Art. In this way, it could save huge amount of labor cost, increasing production speed and production yield significantly. In addition, the costly sewing machine used for sewing the 4 outer rows of decorative stitches of the Prior Art can also be saved.

3. In embodiments of the present invention, shape, color, stitches, texture and outer appearance of a cricket ball can be controlled and varied by using different types of ball cover molds, in achieving effective design and production of the cricket ball.

The above detailed description of the preferred embodiment is intended to describe more clearly the characteristics and spirit of the present invention. However, the preferred embodiments disclosed above are not intended to be any restrictions to the scope of the present invention. Conversely, its purpose is to include the various changes and equivalent arrangements, which are within the scope of the appended claims.

All optional and preferred features and modifications of the described embodiments and dependent claims are usable in all aspects of the invention taught herein. Furthermore, the individual features of the dependent claims, as well as all optional and preferred features and modifications of the described embodiments are combinable and interchangeable with one another

Claims

WHAT IS CLAIMED IS: 1. A cricket ball cover manufacturing method, comprising following steps: forming a ball core; placing a fiber layer consisting of two figure-8 shaped fiber layer pieces around said ball core; winding on said ball core with fine threads to hold said figure-8 shaped fiber layer pieces firmly together, then infusing liquid Polyurethane (PU) into and impregnating said fiber layer; attaching and aligning a masking jig onto an inner side of a ball cover mold, to expose stitch-shaped grooves while covering the rest of the inner side of said ball cover mold; applying or spraying a coloring material on said masking jig to fill said coloring material in said stitch-shaped grooves; removing said masking jig from said ball cover mold; placing the soaked ball core inside said ball cover mold, and then putting said ball core and said ball cover mold into a metal mold holder for said ball core to tightly engage said ball cover mold; heating up said ball cover mold, and curing said ball core and said ball cover inside at 70°C for 3 hours; and removing a finished ball having six rows of bulged stitches formed integrally with said coloring material thereon from said ball cover mold and said metal mold holder.
2. The cricket ball cover manufacturing method as claimed in claim I, wherein said ball core is made of cork, which is layered and tightly wound with strings.
3. The cricket ball cover manufacturing method as claimed in any preceding claim, wherein said fiber layer is porous and is made of pile, felt, natural or synthetic fibers, natural or synthetic yarns, natural or synthetic non-woven cloth, natural or synthetic woven cloth.
4. The cricket ball cover manufacturing method as claimed in any preceding claim, wherein said Polyurethane (PU) is used to smooth over wrinkles and folds on said ball cover giving it a smooth appearance.
5. The cricket ball cover manufacturing method as claimed in any preceding claim, wherein shape, color, stitches, texture and outer appearance of said cricket ball are controlled and varied by using different types of ball cover molds.
6. The cricket ball cover manufacturing method as claimed in any preceding claim, wherein said coloring material of decorative stitches and seam stitches is made of liquid Polyurethane (PU) of white, or light brown color, that is same material used to make said ball cover, but of different color.
7. The cricket ball cover manufacturing method as claimed in any preceding claim, wherein said masking jig is made of metal or plastic.
8. The cricket ball cover manufacturing method as claimed in any preceding claim, wherein numbers of seam slots and decorative slots in said ball cover mold piece are same as numbers of corresponding seam notches and corresponding decorative notches in masking jig pieces respectively.
9. The cricket ball cover manufacturing method as claimed in any preceding claim, wherein said fiber layer is formed by two figure-8 shaped fiber layer pieces matching each other.
10. The cricket ball cover manufacturing method as claimed in any preceding claim, wherein said ball cover mold is made of flexible plastic and formed by two hemispherical ball cover mold pieces matching each other.
11. The cricket ball cover manufacturing method as claimed in any preceding claim, wherein said cricket ball cover has a consistent thickness ranging from 3 to 6 mm.
12. The cricket ball cover manufacturing method as claimed in any preceding, wherein said fiber layer is injected, sprayed, or brushed with said Polyurethane.