GB2337723A

GB2337723A - Producing a textile package

Info

Publication number: GB2337723A
Application number: GB9811578A
Authority: GB
Inventors: Philip Keith Chadwick
Original assignee: GROWTHSCOPE Ltd
Current assignee: GROWTHSCOPE Ltd
Priority date: 1998-05-30
Filing date: 1998-05-30
Publication date: 1999-12-01
Anticipated expiration: 2018-05-30
Also published as: GB9811578D0; GB2337723B

Abstract

A textile package is produced by depositing material such as atomised powders (10) or adsorbent fibres on a first fibrous layer (14), laying a second fibrous layer (12) on the first layer and the deposited material to form a sandwich and directing jets of fluid at the sandwich to thereby bind the first and second fibrous layers together. The contents of the packages may be deposited to form a grid pattern comprising squares, lozenges or rectangles of the contents.

Description

2337723 TEXTILE PACKAGES AND PRODUCTION THEREOF The invention relates to a

method for producing a textile package and to textile packages produced according to the method, in particular, but not limited to, a method for producing non-woven textile packages for adsorbing and/or filtering liquids and/or gases in the medical, geotextile, hygiene, automobile or industrial sectors.

A previous method for making a non-woven textile pad involves spinning a thermoplastic polymer through nozzles, in such a way as to produce a tangle of threads which emerge from the nozzles. Atomised powders are then deposited on the threads in a dusting procedure. The method involves the use of adhesive to secure two layers of the tangled thread material together to form a sandwich having the atomised powders between the tangled thread material.

This method has the disadvantage that flexible particles are used which reduce the efficiency of the atomised powders. Further disadvantages arise in that the cost of producing such packages is very high, the types of fibres which can be used is very limited and the loss of filling is also very high.

It is an object of the present invention to address the above mentioned disadvantages.

According to a first aspect of the present invention a method of producing a textile package comprises:

depositing material to form the contents of said package on a first fibrous layer; L is 2 - laying a second f ibrous layer on the f irst layer and the deposited material to form a sandwich; and directing jets of fluid at the sandwich to thereby bind 5 the first and second fibrous layers together.

The textile package may be a non-woven textile package; in which case the first and second fibrous layers may be nonwoven fibrous layers, which may be made by carding, air laying, staple webbing or other known methods.

Each fibrous layer may comprise a single type of fibre, or alternatively may comprise a mix of fibres. The first and second fibrous layers may be made of different fibres.

The contents of the package may include atomised powders and/or may include adsorbent fibres, or a mixture of the two.

The contents of the package may be deposited on the first fibrous layer in discrete sections. Portions of the first fibrous layer may be exposed between the discrete sections. The contents of the package may be deposited to form a grid pattern, comprising squares, lozenges or rectangles of the contents. The contents may be deposited from a hopper, which may deposit the contents in pulses.

The jets of fluid may be water jets, which may be very fine water jets.

The jets of fluid may be directed at the sandwich when the sandwich is arranged on a firm surface. The jets of fluid may be caused to pass through the sandwich and rebound on the firm surface. The firm surface may be the surface of i 3 a first cylinder, which may be mounted for rotation. The sandwich may be moved past one side of, preferably beneath, the cylinder for treatment of a first face of the sandwich. The sandwich may be moved passed the opposite side of, preferably above, a second cylinder for treatment of a second face of the sandwich. The first and second cylinders may be mounted for counter rotation.

The action of the jets of fluid may result in fibres of the sandwich being tangled. The first and second fibrous layers may be tangled together. The tangles may be in the form of knots.

Tangles may result from the rebounding of the fluid on is the firm surface. The fibrous layers may be more strongly bound together in sections where none of the contents are deposited on the first fibrous layer.

Both faces of the sandwich may be treated.

The sandwich may be subsequently dried, preferably in an oven.

The invention extends to a textile package produced by the method of the previous aspect.

The textile package may be a non-woven textile package.

According to a further aspect of the present invention a textile package comprises first and second fibrous layers with contents of the package trapped therebetween, in which the fibrous layers are bound together by interengagement of fibres in those layers.

1 4 - The textile package may be a non-woven textile package The interengagement may be the result of a hydraulic binding process, such as that described in the first aspect.

All of the above aspects may be combined with any of the features disclosed herein, in any combination.

A specific embodiment of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which:

Figure 1 is a schematic side view showing the introduction of atomised powders between two non-woven fibrous layers;

Figure 2 is a schematic top view, showing at the right hand side the fibrous layers of figure 1 before the atomised powders are deposited and at the left hand side the appearance of the fibrous layers after the deposition of the atomised powders; Figure 3 is a schematic side view of the sandwiched material as it is passed over and between counter- rotating drums for application of a hydraulic binding process; and Figure 4 is a schematic sectional side view of the fibrous layers with atomised powders in between before (right hand side) and after (left hand side) the hydraulic binding process.

A method of producing a non-woven textile package involves sandwiching atomised powders 10 or adsorbent fibres between two non-woven fibrous layers 12 and 14, passing the sandwich 16 between counter- rotating drums 18 and 20 and directing jets of water at the sandwich 16.

In more detail, the non-woven fibrous layers 12 and 14 are obtained by known methods such as carding, air laying, staple webbing or other methods known in the textile sector. The two fibrous layers may be made of the same material, or alternatively may be made of different material. The fibres for the non-woven fibrous layers 12 and 14 which may be used alone or as a mixture of fibres are chosen from the group of thermoplastic fibres including polypropylene, polyethylene, polyester, polycarbonate, polyamide fibres, the group of para-aramide and meta-aramide fibres, the group of is fluorocarbonated fibres, mineral fibre groups such as E, C or R glass, ceramic fibres, the group of pre-oxidised acrylic fibres, carbon fibres, natural fibres such as cotton, silk, jute, linen, wool, synthetic fibres such as viscose or thermoplastic micro-fibres and metallic fibres. The length of the fibres in the non-woven fibrous layers 12 and 14 may vary between 5 and 120mm, with diameters of between 1 and 100pm. As shown in figure 1, one of the non-woven fibrous layers 14 is arranged horizontally and the atomised powders 10 are deposited thereon from a hopper 22. The other of the non-woven fibrous layers 12 is then introduced from above to lay on top of the atomised powders 10 on top of the lower non-woven fibrous layer 14.

The atomised powders are deposited in the distribution shown in figure 2. The powders 10 are located in the shaded regions 10. The interstices of the distribution may be separated by between imm and several centimetres. The powders 10 may have a trellis formed by lozenges, rectangles, squares 6 - or any other shape of trellis. Sections of non-woven f ibrous layer 14 having no atomised powder 10 thereon are left in order to assist the binding process of the two fibrous layers 12 and 14, which will be described below. The pattern of atomised powders 10 seen in figure 2 is achieved by using a number of hoppers 22 arranged across the width of the fibrous layer 14, or alternatively a single hopper with a number of openings. The atomised powders 10 have a mesh size of between 3 and 250, and a specific surface area of between 500 and 1500 m2/g.

The powders/adsorbent fibres may be selected depending on the application from diatomaceous earths, sphagnum moss, wood pulp, coconut, activated carbon, asbestos and aramide pulp or fibres, acrylic, carbon, viscose, PTFE or zeolite fibres or pulp.

The sandwich 16 of f ibrous layers 12 and 14 and atomised powders 10 and/or adsorbent fibres is then passed to the counter-rotating drums 18 and 20 (see figure 3).

The sandwich 16 is fed beneath the first drum 18, at which point very fine jets of water are directed at a first face of the sandwich under very high pressure, between 20 and 300 bars, for instance. The water passes through the fibrous layers 12 and 14 and the atomised powders 10 therebetween. Re-bounding of the water on the drum causes the fibres in the fibrous layers 12 and 14 to form knots at the surface. Also, knots are formed between the two fibrous layers 12 and 14 in particular at the intersections in the trellis pattern formed by the atomised powders. In these places the fibrous layers 12 and 14 can easily contact each other without the interference of the atomised powders 10.

7 - The sandwich 16 is then passed between the counterrotating rollers 18 and 20 to pass over the top of the second roller 20, at which point further jets of water under high pressure are directed at the fibrous layers to process a second face.of the sandwich 16.

After the treatment with the jets of water the sandwich 16 has the form shown to the right hand side of figure 3, in which the fibrous layers 12 and 14 and in particular the areas with no atomised powders therebetween have been substantially compressed and knotted together around the sections of atomised powder 10 to hold the powders 10 in position between the two fibrous layers 12 and 14. The surfaces of the fibrous layers 12 and 14 have also been knotted and the powders 10 and fibrous layers 12 and 14 have been consolidated.

The sandwich is then dried in a circulating air furnace.

The non-woven package produced by the process described above is characterised by having very high mechanical properties compared to prior art packages and also a very small loss of filling due to the advantageous knotting between the fibrous layers 12 and 14. The package has a weight in the range 30 to 600 9/m2. The weight of the powders 10 and/or adsorbent fibres is between 5% and 90% of the total weight. The non-woven package has interesting characteristics relating to the filtration of liquids, the filtration of gases and the adsorption of fluids and gases.

Furthermore, the areas of application are many and varied, depending on the actual composition of the fibres of the fibrous layers 12 and 14, the atomised powders 10 and/or the adsorbent fibres.

In the medical sector, it would be possible to use, for example, a nonwoven package consisting of one face with a fibrous layer for example cotton, activated carbon in the form of grains with a mesh size of 15 units or more in the centre and on the other face, a layer of thermoplastic fibres. Possible applications are antibacterial non-woven clothing, post operative bags, and filters for blood all for clean rooms.

A different type of use, in the geotextile sector would be, for example, a non-woven package consisting of one face with a polyamide f ibrous layer, diatomaceous earth at the centre and, on the other face, a polyamide fibrous layer. Possible applications are road drainage, the filtration of sea-borne pollutants, domestic and industrial discharges.

In the hygiene sector, it would be possible to use, for example, a nonwoven package consisting of one face with a viscose and cotton fibrous layer, a sphagnum moss and activated carbon filling and, on the other face, a thermoplastic fibrous layer. Possible applications are disposable nappies, incontinence pads and sanitary towels.

In the automobile sector, it will be possible to use, for example, a nonwoven package consisting of one face with a thermoplastic f ibrous layer, activated carbon at the centre and, on the other face, a thermoplastic fibrous layer. Possible applications are petrol tank canisters, air filters for the engine, oil filters and filters for particles, gases and odours in the passenger compartment.

In the industrial filtration sector, it would be possible to use, for example, a non-woven package consisting of one face with a PTFE fibrous layer, zeolites at the centre and, on the other face, a PTFE fibrous layer. Possible applications are filters for industrial distilleries, filters for purification plants, factory filters and kitchen filters.

The reader's attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

is All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanying claims, abstract and drawings), may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel - combination, of the steps of any method or process so disclosed.

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Claims

A method of producing a textile package comprises:

depositing material to form the contents of said package on a first fibrous layer; laying a second fibrous layer on the first layer and the deposited material to form a sandwich; and directing jets of fluid at the sandwich to thereby bind the first and second fibrous layers together.
2. A method as claimed in claim 1, in which the textile package is a nonwoven textile package.

is
3. A method as claimed in claim 2, in which the first and second fibrous layers are non-woven fibrous layers.
4. A method as claimed in any preceding claim, in which the contents of the package include atomised powders.
5. A method as claimed in any preceding claim, in which the contents of the package include adsorbent fibres.
6. A method as claimed in any preceding claim, in which the contents of the package are deposited on the first fibrous layer in discrete sections.
7. A method as claimed in claim 6, in which portions of the first fibrous layer are exposed between the discrete sections.

12 -
8. A method as claimed in any preceding claim, in which the contents of the package are deposited to form a grid pattern, comprising squares, lozenges or rectangles of the contents.
9. A method as claimed in any preceding claim, in which the contents are deposited from a hopper.
10. A method as claimed in any preceding claim, in which the jets of fluid are water jets.
11. A method as claimed in claim 10, in which the water jets are very fine water jets.
12. A method as claimed in any preceding claim, in which the is jets of fluid are directed at the sandwich when the sandwich is arranged on a firm surface.
13. A method as claimed in claim 12, in which the jets of fluid are caused to pass through the sandwich and rebound on the firm surface.
14. A method as claimed in either claim 12 or claim 13, in which the firm surface is the surface of a first cylinder.
15. A method as claimed in claim 14, in which the cylinder is mounted for rotation.
16. A method as claimed in either claim 14 or claim 15, in which the sandwich is moved past one side of the cylinder for treatment of a first face of the sandwich.

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17. A method as claimed in claim 16, in which the sandwich may be moved passed the opposite side of a second cylinder for treatment of a second face of the sandwich.
18. A method as claimed in claim 17, in which the first and second cylinders are mounted for counter rotation.
19. A method as claimed in any one of claims 12 to 18, in which tangles may result from the rebounding of the fluid on 10 the firm surface.
20. A method as claimed in any preceding claim, in which the action of the jets of fluid results in fibres of the sandwich being tangled.

is
21. A method as claimed in claim 20, in which the first and second fibrous layers are tangled together.
22. A method as claimed in either claim 20 or claim 21, in 20 which the tangles are in the form of knots.
23. A method as claimed in any preceding claim, in which the fibrous layers are more strongly bound together in sections where none of the contents are deposited on the first fibrous layer.
24. A method as claimed in any preceding claim, in which both faces of the sandwich are treated.
25. A method as claimed in any one of claims 10 to 24, in which the sandwich is subsequently dried.

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26. A textile package produced by the method of any one of claims 1 to 25.
27. A textile package according to claim 26, which is a non woven textile package.
28. A textile package comprises first and second fibrous layers with contents of the package trapped therebetween, in which the fibrous layers are bound together by interengagement of fibres in those layers.
29. A textile package according to claim 28, which is a nonwoven textile package.

is
30. A textile package according to either claim 28 or claim 29, in which the interengagement is a result of a hydraulic binding process, such as that described in any one of claims 1 to 25.
31. A method of producing a textile package substantially as described herein with reference to the accompanying drawings.
32. A textile package substantially as described herein with reference to the accompanying drawings.