WO2001025524A1

WO2001025524A1 - Manufacturing and printing process

Info

Publication number: WO2001025524A1
Application number: PCT/GB2000/003708
Authority: WO
Inventors: Terence Michael Hedley; Neville De Sousa
Original assignee: Walk Off Mats Limited
Priority date: 1999-10-07
Filing date: 2000-09-28
Publication date: 2001-04-12
Also published as: AU7535300A

Abstract

A process is provided for manufacturing a printed article having a primary layer (10) and a rubber backing layer (8). The primary layer (10) is bonded to the backing layer (8) under heat and pressure and a printed image is transferred under heat and pressure onto the primary layer (10) from a transfer sheet (12) carrying an image printed on the transfer sheet (12) in sublimatic dyes. The bonding process and the image transfer process are carried out simultaneously by pressing the primary layer, the rubber backing layer and the transfer sheet together in a heated press (2,16).

Description

MANUFACTURING AND PRINTING PROCESS

The present invention relates to a process for manufacturing printed articles, in particular but not exclusively mats, rugs, carpet tiles and similar articles, and to printed articles manufactured by the process.

In the following description and claims, the term "mat^" is intended to cover floor mats and also other products such as rugs, carpets, carpet tiles, bar runners, rubber mat labels and so on. in which a primary layer, normally but not always a fabric layer, is bonded to a rubber backing under heat and pressure.

In a known mat manufacturing process, a natural or synthetic rubber backing sheet is cured and heat-bonded under pressure to the back of a fabric layer in a heated press. Such a process is described for example in our European patent application No. 0847327, the contents of which are incorporated by reference herein.

It is known to print an image onto such a mat by first screen printing the image onto a paper transfer sheet using sublimatic dyes and then transferring the dyes under heat and a vacuum onto the manufactured mat. The heat causes the dyes to evaporate and the vacuum helps the sublimation process and also ensures good penetration of the dyes into the fabric of the mat. Until recently, this process has only been possible using white polyester mats with a relatively short pile. If a longer pile mat is used, the dye generally diffuses excessively, degrading the quality of the printed image. The process also requires a separate printing step after completion of the mat manufacturing process.

It is an object of the present invention to provide a process for manufacturing printed articles, such as mats, rugs, carpet tiles and similar items, and printed articles manufactured by the process, that mitigate at least some of the aforesaid problems.

It has recently become possible to produce a transfer sheet by a new process, in which sublimatic dyes are printed onto a transfer sheet by means of a digital printer under the control of a computer. We have found that using such a transfer sheet it is possible to print an image of acceptable quality onto both long and short pile mats as well as a range of other fabrics. According to the present invention there is provided a process for manufacturing a printed article having a primary layer and a rubber backing layer, in which the primary layer is bonded to the backing layer under heat and pressure and a printed image is transferred under heat and pressure onto the primary layer from a transfer sheet carrying an image printed on the transfer sheet in sublimatic dyes, said bonding process and said image transfer process being carried out simultaneously by pressing the primary layer, the rubber backing layer and the transfer sheet together in a heated press.

By carrying out the bonding process and the image transfer process simultaneously, the need for separate manufacturing and printing processes is avoided. The process allows printed images of satisfactory quality to be printed on a wide range of articles, including long and short pile mats, smooth fabric, felt and PVC/rubber blends.

Advantageously, the primary layer is a fabric layer. Preferably, the fabric layer is a tufted fabric. Alternatively, the fabric layer may be a felt fabric, a non woven spun bonded fabric, or a woven fabric.

Advantageously, the fabric layer includes polyester fibres, as these give the best wash fastness with the printing dyes, the fabric layer be may be either 100% polyester or a blend of polyester and other fibres, for example cotton or nylon. Alternatively, the fabric layer may include nylon fibres, for example Nylon 6 or 6.6, and may be either 100% nylon or a blend of nylon and other fibres.

Alternatively, the primary layer may be a PVC/Nitrile rubber blend, for example for use in rubber mat labels.

Advantageously, the transfer sheet is a digitally printed transfer sheet.

Advantageously, the heated press is heated to a temperature of approximately 160C to 170C and, preferably, the primary layer, the rubber backing layer and the transfer sheet are pressed in the heated press for a time of approximately 20 minutes.

Advantageously, a frame member is used to form the edge of the rubber backing layer during the pressing process. Preferably, the transfer sheet is aligned with the frame member, prior to being placed the heated press. Advantageously, the rubber backing layer extends beyond the primary layer on at least one side of the article to provide an extended border section, onto which a printed image is transferred from a transfer sheet carrying an image in sublimatic dye. A sheet of ink-receptive fabric may be bonded to the upper surface of the extended border section. The extended border section may be removable by cutting the rubber backing layer adjacent an edge of the primary layer.

The printed article may be cut into a plurality of tiles, and each tile may have a printed border.

Advantageously, the printed article is a mat, preferably a dust control mat.

According to a further aspect of the invention there is provided a printed article having a primary layer printed with an image and a rubber backing layer bonded to the primary layer, said article having been manufactured by a process according to one of the preceding paragraphs.

The article may include an extended border section that carries a printed image.

The article may be divided into a plurality of tiles, each tile having a printed border.

Advantageously, the article is a mat, preferably a dust control mat.

Advantageously, the primary layer is a fabric layer of polyester tufted fabric.

Embodiments of the invention will now be described by way of example with reference to the accompanying drawings, in which:

Figure 1 is an exploded cross-sectional view of a laid-up mat in a heated press;

Figure 2 is a side view of a mat with an extended border section made according to the process;

Figure 3 is a plan view of a tiled mat made according to the process, and

Figure 4 is an exploded cross-sectional view of a tiled mat laid-up in a heated press.

In a typical mat manufacturing process, a natural or synthetic rubber backing sheet is cured and heat-bonded under pressure to the back of a fabric layer in a heated press. The fabric layer typically consists of a tufted polyester pile on a non-woven polyester substrate. The rubber backing is normally slightly larger than the fabric layer to form a rubber border, which is typically about 2cm wide. The rubber backing layer and the fabric layer are laid up on a nonstick release sheet, for example of PTFE-coated woven glass fabric, and are covered with a top cover, also of PTFE-coated woven glass. The mat is then placed in the press for the bonding and curing process.

Figure 1 is a schematic exploded cross-section of a laid up mat in a press. The press includes an inflatable diaphragm 2 upon which there is placed a bottom release sheet 4 of PTFE-coated woven glass. An aluminium frame 6 the size of the finished mat may optionally be placed on the bottom release sheet 4 to shape the edge of the rubber backing sheet and provide a reinforced border, as described in our European patent application No. 0847327.

The mat, which is laid up on the bottom release sheet 4, consists of a rubber backing sheet 8 and a tufted fabric layer 10. The rubber backing sheet 8 is normally slightly larger than the fabric layer 10 so as to form a rubber border, and also overlaps the inner edge of the frame 6 so that, during the bonding and curing process, the edge of the backing sheet is cut off by the frame. Alternatively, the rubber backing sheet may be accurately cut before being laid up, for example by means of a dye cutter, to fit just inside the frame.

When the mat has been laid up, a transfer sheet 12 that has previously been printed with the desired image using sublimatic dyes is placed face down on top of the fabric layer 10. The dimensions of the transfer sheet 12 are preferably matched to the outer periphery of the frame 6 so that the frame can be used to ensure correct alignment. A top cover 14, of PTFE-coated woven glass, is placed on top of the laid up mat, and the mat is then placed in the press between a heated metal platen 16 and the inflatable diaphragm 2 for the bonding and curing process.

The press is typically heated to a temperature of about 160-170 °C. The diaphragm 2 is inflated, for example to a pressure of 30 pounds per square inch, pressing the mat against the heated platen for a cycle time of approximately 20 minutes. The heat from the platen softens and cures the rubber backing, and the pressure from the diaphragm presses the fabric layer into the rubber backing, bonding the two layers together. At the same time, the dyes on the transfer sheet 12 evaporate and are transferred onto the fabric of the mat to form a printed image. The process therefore has the advantage that the mat is manufactured and printed in a single step, rather than two separate steps. There is thus no need for a separate printing step and the manufacturing and printing process is therefore quick and simple.

The mat manufacturing and printing process described above is applicable to a wide range of mat and carpet materials. Some example are provided below:

1. Polyester tufted fabric. The process may be used for printing dust control mats, which typically have a polyester tufted fabric made from a yarn of 100% polyester Cotton Count 1.3's semi worsted spun, two ply twisted and heat set, in a fabric having a pile weight of 900g/m² cut pile. Whilst this is our standard specification for a dust control mat, variations on yarn count and tufting specification including loop pile would also be suitable. The polyester fabric gives good wash fastness for the dyes used and this feature makes the fabric ideal for laundered products, such as washable dust control mats.

2. Polyester felt. For example, the process may be used to print 100% polyester needled felt having a weight of 500g/m². Other weights would also be suitable.

3. Non woven spun bonded polyester. This material is normally used as a primary backing material for tufted carpets at weights of 80-160g/m², or for roofing felt at weights up to 230g/m². A weight of 230g/m² has been found to give the best results, because at lower weights the rubber backing flows through to the surface of the material, giving a poor quality print definition. Other weights lighter than this might be suitable, and the rubber can be prevented from flowing through to the surface by decreasing the pressure of the press during manufacturing and/or by adjusting the rubber formulation to restrict the flow.

4. Woven polyester fabric. Any woven polyester fabric or polyester cotton blend is suitable, providing that the weight and weave are suitable to prevent the rubber flowing through to the surface. For example, a suitable material comprises polyester-cotton blend having a polyesteπcotton ratio of 67:33 and a weight of 270g/m².

5. White PVC/Nitrile blend. This is the material we use to make rubber labels, which we normally screen print using PVC based coloured inks to produce edge or back labels for our mats. A suitable material comprises a PVC/Nitrile blend having a ratio of 30:70 and a thickness of 0.015" (0.38mm).

The above are intended only as examples and we believe that any fabric or sheet material that contains or consists of polyester and that bonds to a rubber backing would also be suitable.

The process may be employed to manufacture a wide range of products, including dust control mats, other loose-laid mats (for example carrying promotional and advertising material), play mats, printed domestic mats (for example bearing the badges of sports teams) and bar runners, as well as carpet tiles and other products.

Although polyester or polyester blend fabrics are the best for launderable products, owing to the wash fastness of the dyes when printed onto polyester, the process also produces good results when printing onto other fabrics such as Nylon 6 or 6.6, which may be suitable for products that do not require repeated laundering.

Figure 2 is a side view of a mat with an extended border section made according to the process. The mat includes a rubber backing sheet 8 of nitrile rubber and a tufted fabric layer 10, for example of polyester. The rubber backing sheet 8 extends approximately 2cm beyond the fabric layer 10 around three sides of the mat to form a narrow rubber border 16, and on the fourth side extends much further beyond the fabric layer (for example, approximately 10-40cm) to form an extended border section 18. A sheet of ink-receptive fabric 20, for example polyester fabric, is bonded to the upper surface of the extended border section 18 during the pressing and curing process.

The provision of the extended border section 18 and the sheet of ink-receptive fabric 20 makes it possible to print a separate message, design or logo on the extended border section 18, in addition to the main design printed on the tufted fabric layer 10. This may be particularly useful for displaying temporary messages, advertisements or promotions. When the temporary message is no longer required, the extended border section 18 can be cut off with a sharp knife along the inner edge 22 of the fabric layer 20, leaving a mat of conventional design with a continuous narrow rubber border.

Figure 3 is a plan view of a tiled mat made and printed according to the process described above. The tiled mat consists of a large mat 24 that is divided into a number of separate tiles 26. each of which has a printed border 28 that is approximately 2cm wide. The tiled mat can be cut up into separate small mats by cutting along the edges of the borders 28. Thus, several small mats can be manufactured and printed with identical or different designs in a single process. Each of those small mats will have a black border and will therefore be similar in appearance to a conventional mat with a rubber border, except that the tufted fabric layer will extend to the edges of the mat.

Figure 4 is an exploded cross- sectional view of a tiled mat laid-up in a heated press. The press includes an inflatable diaphragm 32 upon which there is placed a bottom release sheet 34 of PTFE-coated woven glass. The mat, which is laid up on the bottom release sheet 34, consists of a rubber backing sheet 38 and a tufted fabric layer 40 that extends up to the edges of the rubber backing sheet 38. A transfer sheet 42 that has previously been printed using sublimatic dyes with the desired image and the tile borders is placed face down on top of the fabric layer 40. A top cover 44, of PTFE-coated woven glass, is placed on top of the laid up mat, which is placed in the press between a heated metal platen 46 and the inflatable diaphragm 32.

The two layers of the mat are bonded together under heat and pressure in the press and. at the same time, the dyes on the transfer sheet 12 are transferred onto the fabric of the mat to form the printed image and the borders 28. After removal from the press, the tiled mat is cut into separate mat tiles by cutting around the edges of the borders 28, for example with a guillotine or a stamp cutter.

Claims

1. A process for manufacturing a printed article having a primary layer and a rubber backing layer, in which the primary layer is bonded to the backing layer under heat and pressure and a printed image is transferred under heat and pressure onto the primary layer from a transfer sheet carrying an image printed on the transfer sheet in sublimatic dye, said bonding process and said image transfer process being carried out simultaneously by pressing the primary layer, the rubber backing layer and the transfer sheet together in a heated press.

2. A process according to claim 1, in which the primary layer is a fabric layer.

3. A process according to claim 2, in which the fabric layer is a tufted fabric.

4. A process according to claim 2, in which the fabric layer is a felt fabric.

5. A process according to claim 2, in which the fabric layer is a non woven spun bonded fabric.

6. A process according to claim 2, in which the fabric layer is a woven fabric.

7. A process according to any one of claims 2 to 6, in which the fabric layer includes polyester fibres or a blend of polyester and other fibres.

8. A process according to any one of claims 2 to 6, in which the fabric layer includes nylon fibres or a blend of nylon and other fibres.

9. A process according to claim 1, in which the primary layer is a PVC Nitrile rubber blend.

10. A process according to any one of the preceding claims, in which the transfer sheet is a digitally printed transfer sheet.

11. A process according to any one of the preceding claims, in the heated press is heated to a temperature of approximately 160C to 170C.

12. A process according to any one of the preceding claims, in which the primary layer, the rubber backing layer and the transfer sheet are pressed in the heated press for a time of approximately 20 minutes.

13. A process according to any one of the preceding claims, in which a frame member is used to form the edge of the rubber backing layer during the pressing process.

14. A process according to claim 13, in which the transfer sheet is aligned with the frame member, prior to being placed the heated press.

15. A process according to any one of the preceding claims, wherein the rubber backing layer extends beyond the primary layer on at least one side of the article to provide an extended border section, onto which a printed image is transferred from a transfer sheet carrying an image in sublimatic dye.

16. A process according to claim 15, in which a sheet of ink-receptive fabric is bonded to the upper surface of the extended border section.

17. A process according to claim 15 or claim 16, in which the extended border section is removable by cutting the rubber backing layer adjacent an edge of the primary layer.

18. A process according to any one of the preceding claims, wherein the printed article is cut into a plurality of tiles.

19. A process according to claim 18, in which each tile has a printed border.

20. A process according to any one of the preceding claims, wherein the printed article is a mat.

21. A process for manufacturing a printed article, the process being substantially as described herein with reference to and as illustrated by Fig. 1, or Fig. 2, or Figs. 3 and 4 of the accompanying drawing.

22. A printed article having a primary layer printed with an image and a rubber backing layer bonded to the primary layer, said article having been manufactured by a process according to any one of the preceding claims.

23. An article according to claim 22, wherein said article includes an extended border section that carries a printed image.

24. An article according to claim 22, wherein said article is divided into a plurality of tiles, each tile having a printed border.

25. An article according to any one of claims 22 to 24, said article being a mat.

26. An article according to any one of claims 22 to 25, wherein said primary layer is a fabric layer of polyester tufted fabric.

27. A printed article substantially as described herein with reference to and as illustrated by Fig. 1, or Fig. 2, or Figs. 3 and 4 of the accompanying drawing.