DE2518525A1 - SUBSTANTLY CLOSED FABRIC AND METHOD FOR MANUFACTURING IT - Google Patents

Description

PATENT LAWYERS

DR. -IN G. H. Fl N CKE DIPL-ING. H. BOHR DIPL.-ING. S. STAEGER

Patent attorneys Dr. find «· Bohr ■ Staeger ■ 8 Munich S · M0llerttra6e

8 MÖNCHEN B, MOIIerjtroße 31 Telephone: (089) '2600ÄO Telegrams: Claims Munich Telex! 523903 claim d

Folder No. A Please state in the answer

April 25, 1975

description

of Bay Mills Limited Downsview> Ontario / Canada

concerning

"Essentially closed fabric and process for its production"

Priority: 4/26/197 «+ - CANADA

The invention relates to substantially closed fabrics, which by pressure distribution of the threads of at least some the yarns of a coarse-meshed fabric can be produced. The invention is also to methods of making such closed tissue directed.

509847/0793

Bank details: Bayer. Vereintbank Munich, account £ 20 404 · Postal check account: Munich 370 44-802

As is known, a wide-meshed fabric is a fabric at which adjacent warp yarns are spaced from each other and adjacent weft yarns are also in Are spaced from each other so that the tissue has a plurality of openings. A typical large-meshed gauze fabric is shown in Canadian Patent 8 8 2,081 dated September 2, 1971, for example. Such a fabric that is not one Fabric is as it is conventionally made on a loom, but made up of at least two layers of Yarns laid one on top of the other can be used as the starting fabric for practicing the invention. However, it is also possible to have one produced in a conventional manner To use woven fabrics as the starting fabric.

A closed fabric, on the other hand, is a fabric in which either the warp yarns or the weft yarns or both are arranged side by side so that they have essentially no or only very small openings in the goods.

A closed gauze can be produced in this way, for example that weft yarns are placed next to each other, warp yarns next to each other over or under or both over as can also be placed under the weft yarns, usually at right angles to it, and the warp and weft yarns with one suitable adhesive can be combined. The problem with such a closed scrim is that there is none is soft to the touch and requires a large number of yarns.

There are many applications, for example as a padding and carpet underlay, in which a closed fabric with a soft handle may be desirable. Furthermore, the fabric can be used to reinforce vinyl without that a review is obtained.

For a better understanding of the invention, it is described below

5Ö9S47 / 0793

described in more detail in connection with the accompanying drawings, namely show:

Fig. 1 is a perspective view of a coarse-meshed Gauze, which is one of the fabrics used as the starting fabric for practicing the invention can be;

Figure 2 is a sectional view taken along line 2-2 in Figure 1;

Fig. 3 is a perspective view of an inventive closed fabric made from the fabric shown in Figure 1;

Fig. H in a schematic representation a side view of the Equipment that can be used to manufacture the fabric shown in Figure 3;

Fig. 5 is a plan view showing the threads of the fabric after pressure distribution;

Fig. 6 is a view in section along the line 6-6 in Fig. 5, and

FIG. 7 is a view in section along the line 7-7 in FIG.

The coarse-meshed scrim 10 shown in FIG. 1 is made from warp yarns 11 and 12 and weft yarns 13. the Weft yarns are laid parallel to each other and essentially have equal distances from each other. The warp yarns 11 are placed on the weft yarns and are also parallel to each other, are substantially equidistant from each other and run at right angles to the weft yarns.

509847/0793

A 121,.

The warp yarns 12 lie under the weft yarns and are also parallel to one another, running at equal intervals from each other-and. perpendicular to the weft yarns. However, it is necessary to produce the closed one shown in FIG. 3 fabric 14 shown is not essential that the yarns of the different layers are parallel and equidistant from one another, nor is it essential that the yarns be adjacent Lay layers intersect at right angles. These are all criteria that are preferred for the starting tissue exist, but it will be understood by those skilled in the art as the description proceeds that of these are preferred Criteria can be deviated. As best seen in Figure 2, the warp yarns 12 are in the center arranged between adjacent warp yarns 11. Furthermore, the distance between adjacent warp yarns 11 and 12 is the same as the spacing between adjacent weft yarns 13. These are also preferred features, but are not essential criteria, so that a product according to the invention can be made from fabrics other than fabric 10.

In fact, a product according to the invention can consist of a fabric be produced in which the warp yarns 12 are missing or in which the warp yarns 11 are missing, as long as some warp yarns are present, which are on one side of the weft or on both sides and have the task of after the coating with an adhesive to hold the weft yarns in place. If necessary, the weft yarns can be added serve to hold the warp yarns in place.

The warp and weft yarns are made with a thermoplastic Coated upper cover, which serves to relate the yarns to each other and also the threads of the yarns in their Able to hold.

The fabric 10 can be made in various ways

50 98 47/07 "93

A 121, ^

be. For a method for producing the fabric 10, reference can be made to the aforementioned patent specification. The inventive and shown in Fig. 3 closed Fabric 14 is made by distributing the pressure of the yarns of the fabric. The result of the pressure distribution process, the will be described in more detail below, the flattening of the yarns 11-13 in such a way that practically all through the openings delimited by the yarns 11-13 in the fabric 10 are filled with threads of which the yarns 11-13 'are made. The result is a closed fabric with a soft hand in comparison to the hand of the starting material. In contrast In relation to the goods 10, in which the yarns 11 - 13 lie in three separate layers, the yarns are in the goods 14 have been compressed so that they are all essentially in a single layer.

It has been found that, in order to achieve the desired result, the fabrics 10 have certain properties must be set out below.

As far as the yarns are concerned first, the desired result can be achieved if only one layer of the yarns is sufficient is compressed to close the spaces in the tissue. In this case, the other yarn layer is only used to hold the first-mentioned yarns in place, and while this other yarn layer is also compressed pressing them together does little to fill them of the gaps. Therefore, at least one of the yarn layers, namely the one that is primarily used for spreading is provided for filling the interstices, are made from yarns obtained from continuous filaments are. Preferred threads are rayon, nylon, polyester, polypropylene and glass. The aforementioned yarns must also be multi-threaded Be yarns with at least 20 threads per yarn. The aforementioned yarns should preferably be fixed so that they

509847/0793

do not shrink during the pressure distribution, since otherwise wrinkles will be obtained in the goods 14. The aforementioned yarns should preferably have zero twists per inch, but in each case no more than one twist per inch. Furthermore is to prefer that the denier per yarn is 200 or more.

Preferably, all of the yarns in the fabric 10 or in another coarse-meshed fabric that is used instead of the fabric 10 can be used which have the aforementioned properties, which is the case with yarns 11-13.

However, if the fabric 10 is made of only warp yarns 11 and weft yarns 13 and only, for example, the warp yarns are used to expand and fill the spaces, only the warp yarns need the properties mentioned to have. In this case the weft yarns would only have the task of keeping the warp yarns in place keep. They can be as far apart as the accomplishment of this task allows, and they can generally be made in any manner and from any material, so long as that material is compatible with the other materials used in the fabric and so long as the weft yarns off. are sufficiently strong that they can perform the required function. However, it is decidedly preferable that all yarns have the properties described above, since this means that the fabric IH is more homogeneous.

The fabric 10 must also have certain properties so that the desired result can be obtained. In particular must be the denier per inch of the yarns extending in and under substantially the same direction the pressure distribution to fill the spaces should be at least 4000. This criterion is therefore

509847/0793

A 121 * v

does not apply to the weft yarns in the above example, in which only the warp yarns are used to widen and fill the spaces, although it applies to the warp yarns. In the case of the fabric 10 this requirement is met by warp yarns 11 and 12 together Accounted for and also by filling yarns 13. It is decidedly preferable that this requirement is met by both the warp yarns as well as the weft yarns are taken into account in order to achieve a homogeneous product, and preferably the denier per inch of the warp and weft yarns is said to be essentially the same for the same reason. From the For the same reason, it is desirable that the denier per yarn of the warp yarns is substantially the same as the denier per each Cam is the weft. In fabric 10, the denier is per yarn the warp yarns 11 and the weft yarns are the same. In addition, the number of wefts per inch is the same as the total number of warp yarns per inch. If the fabric 10 consists only of warp yarns 11 and weft yarns 13, both yarns should preferably the same denier per yarn.

So that the desired results can be achieved, the open area of the fabric from which the goods are made should be will not be more than 70% of the area of the fabric. The open area of the closed goods IH should preferably be about 0%, depending on the use the goods are to experience, but the open area in each should be Trap can be reduced by at least 50%. Therefore, when we speak of an essentially closed tissue here is meant a product with an open area of no more than 35% of the area of the fabric.

The type of thermoplastic coating is also important. It must have a softening point that is lower than that of the threads of the yarns which are widened during the pressure distribution to fill the interstices.

^v - 7 509847/0793

Examples are polyvinyl chloride, polyvinyl acetate and polyesters of low softening point. If polyester threads must be used together with a thermoplastic coating, which is also a polyester The latter have a lower softening point than that of the polyester threads.

The amount of coating to be used will vary depending on the yarn and the type of coating being used The minimum amount of the thermoplastic coating is about 5% based on the weight of the coated yarn. The preferred amount is on the order of 50%. However, much larger quantities can be used, in which cases it must be taken into account that the grip of the goods 14 becomes harder. The thermoplastic coating has the task of connecting the yarns 11-13 of the fabric 10 to one another. In the goods IH, the coating holds the Threads of yarn in their position after going through the pressure distribution process have been spread.

For the description of how the goods 14 are made from the fabric 10 reference is made to FIG. In Fig. 4 three rotatable rollers 15, 16 and 17 are shown. The reels are rotatably mounted, the roller 15 being mounted in bearings (not shown) which are in the frame (not shown) are slidable, which rollers are excited and which are driven to change the pressure between the rollers can. A suitable motor (not shown) and a gearbox are for driving the rollers in the indicated directions intended. Furthermore, there is an auxiliary roller 18, which is mounted on an axle that is connected to the axes of rotation of the rollers 15 - 17 is parallel ^ together with a freely rotating intermediate roller 19 provided.

The roller 18 is heated to preheat the fabric, which is from

- 8 509847/0793

a supply reel (not shown) is angled. The effect of preheating is to soften the thermoplastic coating in such a way that the threads of the yarns can be spread out. The roller 15 is also heated to such a temperature that the thermoplastic coating remains soft. When the fabric 10 passes between the rollers 15 and 16, the pressure distribution of the threads of the yarn takes place. This can best be seen from FIGS. 5-7, in which only the weft yarns 13 are shown for the sake of clarity. When these yarns pass between the rollers 15 and 16, their threads, which were parallel to each other up to this passage, are spread out, remaining parallel to each other, so that they occupy the spaces which previously existed between the yarns, naturally the thickness the yarn decreases significantly. An important feature of the invention is that, after the filaments have been spread out as shown in Figure 5, they are held under tension in contact with a cool surface for a period of time sufficient for the thermoplastic coating to harden sufficiently that the threads cannot return to their original positions. This is achieved in that the contact between the product 14 and the roller 16 is maintained after the fabric between the rolls has passed 15 and 16, as shown in Fig. ^. It has been found that if this measure is not used and the pair is immediately removed from them after passing between rollers 15 and 16, the threads tend to return to their original positions, whereby a coarse-meshed fabric is obtained. The fabric lh is pulled off the roller 16 after the thermoplastic coating has hardened sufficiently and can then be cooled further to room temperature in order to prevent blocking before it is taken up by a take-up reel (not shown).

509847/0793 ORIGINAL INSPECTED

In the arrangement according to FIG. 4, the roller 17 only serves to keep the roller 16 cool. The roller 17 can be a Steel roller and, for example, water-cooled to the roller 16, which is preferably a cotton roller, on a To keep the surface temperature below the softening point of the thermoplastic coating. The roller 15 can be a steel roller and, like the roller 18, be heated by steam, electrically or in some other way. The speed of the tissue can vary within wide limits. At higher speeds, however, larger ones occur Difficulty preheating the tissue.

In a particular example of the process, a fabric 10 of the type shown in Figure 1 and having the following was made Properties used: 7 1/2 polyester yarns each 25.4 mm (each Zd.1) both in the warp and in the weft direction, each 1000 denier yarn and composed of 19 2 threads, per yarn with 0.035 twists per 25.4 mm (per inch), coarse-meshed fabric, polyvinyl chloride coating (53% by weight of the coated fabric) fabric 48% open.

Rollers 15-17 had the following diameters: 15.24 cm (6 "), 25.15 cm (9.9") and 22.86 cm (9 "), respectively. The tissue was preheated to 126.7 ⁰ C (260 ⁰ F). The roller 15 was (360 F ⁰⁾ heated to 18 2.2 ⁰ C and the roller 16 was maintained at a temperature of about 71.1 ° C (160 ⁰ F approximately). A pressure of 238.3 kp (525 lbs) per linear 25.4 mm (per linear inch) was applied between the two rollers 15 and 16. The speed of the fabric was 5.50 m (18 feet) per minute.

After the tissue 10 has passed through the device it was found that all of the yarns have been spread out to occupy the spaces. The open area of the fabric was reduced by 96% and its thickness by

- 10 509847/0793

Λ *

5 6%. It was soft to the touch.

In this context it is important to point out that the closed state of the goods 14 is not due to the thermoplastic coating is achieved, which flows into the spaces between the yarns and occupies them. There is of course a flow of the thermoplastic coating instead, however, the interstices are filled by spreading out and flattening out the yarns. if Ex-stock yarns are used, the pressure distribution process reduces the thickness of the fabric by at least 30% discounted.

Although the foregoing preferred embodiments of the invention have been described, various modifications can be made by the person skilled in the art within the scope of the same will.

Patent claims:

- 11 -

509847/0793

Claims (1)

Claims 1. Essentially closed fabric, characterized by the fact that it is produced by distributing the pressure of the threads by at least some of the yarns of a wide mesh fabric with an open area less than 70% of the area of the Fabric, which wide-meshed fabric of the type with at least a layer of warp yarns and at least one layer of weft yarns, both in the case of the coarse-meshed as well as in the closed fabric the warp yarns and the weft yarns intersect at an angle, at least the yarns of one of the aforementioned two groups of yarns by continuous filaments at at least 20 threads per yarn are formed, at least the yarns of the mentioned one group and no more than one twist each have 25.4 mm (per inch), the denier each 25, H mm (each Inches) at least the mentioned one group of yarns is at least UOOO, the mentioned yarns with at least 5% based on the weight of the coated yarns are coated with a thermoplastic material, its Softening temperature is lower than that of the threads, the essentially closed fabric has an open area which is at least 50% less than the open area of the coarse mesh and substantially all of the yarns lie in a single layer and at least the mentioned extended threads together with the threads of the other Group the previously open area of the coarse-meshed fabric - 12 - 509847/0793 take in. 2. Fabric according to claim!,. Characterized in that the Yarns of the aforementioned one group in each layer thereof are substantially parallel to one another and substantially have the same distances. 3. Fabric according to claim 1, characterized in that the denier of each yarn of at least the yarns of said one Group is at least 200. Fabric according to claim 3, characterized in that all yarns are formed by continuous threads and at least 20 threads per yarn, all yarns no more than one twist per 25.4 mm (per inch) and a denier of at least one 200 and the denier of 25.4 mm (per inch) of both the warp and weft yarns is at least 100,000. 5. Fabric according to claim 1, characterized in that the The warp yarns and the weft yarns cut each other at right angles. 6, fabric according to claim 1, characterized by two layers of warp yarns and a layer of weft yarns, the latter being located between the warp yarn layers. - 13 - 509847/0793 7. Fabric according to claim.1, characterized in that the Threads are selected from the group consisting of rayon, nylon, polyester, polypropylene and glass. 8. A fabric according to claim 1, characterized in that the yarns of said one group have zero twists per 25.4 mm (per inch) have. 9. Fabric according to claim 1, characterized in that the thermoplastic material is selected from the group consisting of polyvinyl chloride, polyvinyl acetate, and polyesters is. 10. Fabric according to claim 1, characterized in that the weight of the thermoplastic material is about 50%, 11, fabric according to claim 1, characterized in that the Thickness of the closed fabric is at least 30% less than the thickness of the coarse-meshed fabric. 12. Fabric according to claim 1, characterized in that the open-mesh fabric by at least two superimposed Layers of yarn is formed. 13. Fabric according to claim 12, characterized in that the Yarns of the mentioned one group in each layer of the same 509847/0793 Αϊ are substantially parallel to one another and are substantially equidistant from one another. Fabric according to claim 12, characterized in that the denier per yarn of at least the yarns mentioned a group is at least 200. 15. Fabric according to claim I ¹ +, characterized in that all yarns are formed by continuous filaments and have at least 20 filaments per yarn, all yarns have no more than one twist per 25.4 mm (per inch) and a denier of at least 200 and the denier per 25.4 mm (per inch) of both the warp and weft yarns is at least 4,000. 16, fabric according to claim 15, characterized in that the Yarns of each group in each layer thereof are substantially parallel to one another and are substantially the same Have distances from each other. 17. Fabric according to claim 16, characterized in that the thickness of the closed goods is at least 30% less than is the thickness of the coarse mesh. 18. Fabric according to claim 17, characterized in that the warp yarns all have the same number of threads per yarn, the weft yarns all have the same number of threads per yarn, the number of threads per 25.4 mm (per inch) of the warp ■ - 15 509847/0793 and weft yarns are the same and the denier is 25 * £ mm each (per inch) the warp and weft yarns are the same. 19. Fabric according to claim 18, characterized in that two layers of warp yarns and one layer of weft yarns are provided are, which latter is located between the warp yarn layers. 20. Fabric according to claim 19, characterized in that the warp yarns and the weft yarns to each other at right angles overlap. 21. Process for producing a substantially closed Goods of the type characterized in claim 1 made of a coarse-meshed fabric of the type described in claim 1 Kind, characterized in that the coarse-meshed fabric with the thermoplastic material in one soft enough to allow the filaments to spread out when subjected to pressure , the coarse-meshed fabric is passed through the 'gap between two rotating rollers which the one on a surface temperature at that mentioned gap is heated above the softening point of the thermoplastic material, but to a lower one Temperature as the softening temperature of the mentioned threads, and the other of the mentioned rollers a surface temperature which is lower than the softening temperature of the thermoplastic material is sufficient Pressure is exerted on the coarse-meshed fabric by the rollers so that the threads are spread out around the to close openings in the coarse-meshed fabric so far, - 16 5 0 9 847/0793 that the open area of the coarse-meshed fabric by at least 50% is reduced, and the substantially closed tissue is peeled from the gap, wherein the essentially closed tissues under tension and in contact with the surface of the others mentioned Roller immediately after the fabric has passed through the mentioned gap, held for a time is, which is at least sufficient that the thermoplastic material hardens so far that the threads mentioned in be held in their extended position. 22. The method according to claim 21, characterized in that the soft state of the thermoplastic material is characterized it is achieved that the coarse-meshed fabric is heated to at least the softening point of the thermoplastic material is, however, to a lower temperature than the softening temperature of the threads mentioned, which Coarse-meshed fabric passed through the gap between the mentioned rotating rollers in the preheated state will. 23. The method according to claim 22, characterized in that the difference in thickness between that in said Gap entering coarse-meshed fabric and the mentioned essentially closed goods, the mentioned Gap leaves at least 30%. Method according to claim 22, characterized in that the coarse-meshed fabric is formed by at least two - 17 - 509847/0793 / r laid yarn layers is formed. 25. The method according to claim 2H, characterized in that the denier per yarn of at least the yarns of said one group is at least 200. For: BAY MILLS LIMITED «MM ·. H. FINCKE DiPL-ING. H. BOHR OtPUING. S. STAiGEK - 18 - 509847/0793