Field of Invention:

The present invention relates to a woven fabric made from bast yam and bast compatible non-bast yam, its method of manufacturing and a sack/bag made from such fabric. In particular, the invention relates to the fabric made from bast yam and bast-compatible non bast yam to make sacks/bags for packaging applications, especially for perishable goods/commodities.

Background:

Bast fibres are one of the strong natural fibres and generally obtained from the outer cell layers of the stems of various plants. Among the main plants used for the supply of bast fibres are flax, jute, hemp, ramie, sisal and kenaf. However, the best example is Jute fibre. Jute is an environmentally friendly fibre and is renowned for its bio degradable and reusable/ recyclable properties. In India, approximately 84% of total jute produced is used for sacks, storage, and packaging purposes. Jute bags are ideal for storing food grains as they allow air circulation, which ultimately preserves the freshness of food grains. Bulk goods packaging bags especially for food-grains, are made from bast fibres like jute.

As has been observed over the years, there are significant fluctuations in the area under cultivation of jute in India. As the area of raw jute production varies, the production of raw jute crop fluctuates. The main factors responsible for fluctuation in production of jute are changes in rainfall pattern during sowing season, average jute prices realized during previous jute season and the returns realized from the competing crops during the previous seasons. Due to these reasons, Indian jute mills continually face shortage of raw material, which has resulted in closure of many jute mills and denial of Jute bags to Food grains procurement agencies in the country. Also, many mills have started importing jute material. Over the years there have been some attempts in finding alternatives to jute shortage.

In the past, the issue of packaging bulk goods requiring passive ventilation, such as potatoes and onions, has been addressed by EP3067290A1 which teaches the method of making and usage of jute sack intended to be filled with bulk goods, such as potatoes and onions, comprising a first woven wall and a second woven wall, which walls at a top edge of the sack leave a filling opening open and which have been attached to each other or merge into each other along two longitudinal edges and a bottom edge of the sack, wherein the walls have been formed with jute warp threads and jute weft threads extending transverse thereto, wherein the weft threads successively alternately pass over the warp threads and under the warp threads while keeping a distance between the adjacently extending warp threads and weft threads in order to keep first airing openings open in between them, wherein at least one of the walls has been provided with an elongated airing way in which only the warp threads or the weft threads are present in order to keep second airing openings open in between them, wherein the airing way has a width exceeding the width of the first airing openings.

Mukhopadya and et. Al, in “ Properties of Jute-Synthetic union fabrics ”, IJFTR Vol.l7(l), March 1992, pg. 15-22, also suggested the formation of Jute-HDPE union fabrics prepared with various combinations of jute yam and HDPE flat tapes give improved properties as compared to the corresponding all-jute fabrics. The cement bags made from the various combinations of jute and HDPE and having a HDPE tape film laminated inside by application of heat, are much lighter than those made out of all-jute cloth. It also teaches that the inclusion of synthetic tape in hessian jute fabric opens the possibility of spot bonding of LDPE or LLDPE film for lamination. This type of lamination will completely avoid the use of bitumen for lamination in making fertilizer bags. However, this research paper also indicates drawback that there is decrease in seam strength with usage of HDPE tape in union fabric. Also, this document does not indicate that such fabric is useful for packaging perishable goods such as food grains.

However, such union fabric cannot be used for packaging of commodities/goods requiring aeration. Since such fabric is very compact and will not allow aeration which is needed for long term storage of such commodities/goods. It is also prone to damage on frequent sampling by Parkhi which causes hole resulting in spilling/ seepage of grains hence not suitable for adopting for long term storage of such commodities/goods.

Parkhi test a sampling method is quite prevalent in India. It is carried out using a device colloquially known as a “Parkhi”. It is a device typically made of steel and used for collecting small quantity of sample from a lot of cereals/food grains kept in bags/sacks. The device is available in various sizes. Food Corporation of India (FCI) Quality Manual 2020 provides detailed advice on “Sampling with ‘Parkhi’” in accordance with the provisions of IS 2816: 1964. The FCI manual clearly states that ‘Parkhi’ is commonly used for cereal sampling. A Parkhi is inserted in the bag in a diagonal position and the sample is collected at the other end by gentle turning of the device. The sample collected is then taken to the laboratory for testing. Since such Parkhi testing or sampling leads to an opening in the fabric, fabric construction needs to be robust enough to withstand Parkhi testing to avoid such openings. If the weaving pattern is too tight, or if the surface of the bag is woven very tightly, the chances that holes formed in the bag will retain their shape are very high. Depending on the size of such holes, oozing of food grains from the holes generated during the Parkhi insertion/ sampling is a real problem for conventional bags.

FR7636739A also discloses woven polypropylene incorporating jute threads for increased friction - to inhibit slipping of sacks or bags wherein in the weave some strands of a non-slip water-absorbent material of animal, mineral or vegetable origin, preferably jute, are incorporated. The non-slip strands may be evenly distributed throughout the weave, preferably are concentrated in stripes at interval aligned with the warp tapes of the basic weave. The extra strands may be in a colour or pattern which contrasts with the polypropylene tapes. In an example, a weave weighing 133 g/m2 involving 45 strands per 10cm. warp and weft of a mixt. of 110 Tex propylene tapes and jute yams of metric no. 2 or 3 (km/kg), were used. However, woven fabric disclosed in this document with usage of polypropylene tapes suffers from the same problem of damage on frequent sampling by Parkhi which causes formation of hole resulting in seepage of grains.

Also, PCT/IB2019/061388 (IN357944) teaches the method of making composite fabric using jute and PP bulk yam along with slit film tape yam on circular loom machine. However, fabrics as disclosed showed inherent drawback of hole formation or puncture in fabric structure during the period sampling of goods/commodities stored in bag with help of special knife, conventionally known in India as ‘Parkhi’ . Further, the polyolefin tape stiff yams used in composite fabric showed deterioration due to sunlight/UV exposure, causing pre-mature failure in some cases. Moreover, when parkhi test is conducted, tape/stiff yam is very prone to breakage or damage on frequent sampling which causes holes in the fabric of the bag resulting in spilling/seepage of grains hence not suitable for adopting for long term storage of such commodities or goods. Also, if the amount of film tape increases in fabric the seam/stitch strength decreases. Therefore, strength of the seam or stitch obtained is less than what is necessary.

The above mentioned, Indian Patent no. 357944 further teaches a composite fabric made of Jute yam and synthetic yam in warp and weft direction respectively made on a circular loom in the form of a tubular fabric. However, the fabric as claimed in the said patent is manufactured on a circular loom which uses jute yam of low denier because of which the fabric is of lower weight (per sqm) from 8 to 11 lbs as the circular looms cannot cope with weaving of fabric using a higher weight Jute yam. Due to the tight weave of the fabric obtained on a circular loom, it does not allow the effective aeration needed for the purpose of packaging of those commodities which require aeration or a loose weave for functional performance. It is well known to a person skilled in the art that loose weave with high weight Jute yam is more porous hence allows better permeability. Moreover, the weaving of fabric on a circular loom machine specially of higher weight/ denier yam of bast fibre creates fluff in the weaving device thereby resulting in wastage of bast yam and in frequent stoppage of the circular weaving machine. Hence one of the prime reasons for getting wastage and fluff on circular looms is that these machines are not designed to weave Jute in higher percentage. Circular looms are primarily designed for weaving of tapes and mn at very high speeds which Jute yam cannot withstand. Use of jute yam in weft direction on a circular loom results in higher friction causing fluff generation resulting in higher wastage. Added to this is the frequent stoppage of loom machine which also results in lower production. This is one of the reasons that higher weight/denier Jute yam cannot run on circular looms.

It has also been observed that in the past, the synthetic yam has been used for hosiery and textile products using knitting machinery but never been used for producing the fabric on flat loom machine so far.

With increase in demand and shortage in natural fibre supply, there is a need to develop a suitable packaging fabric having combination of bast fibre yam and bast compatible non-bast yam which is loose in weave and provides adequate aeration for storage of perishable goods and subsequently manufacturing of sack/bag for the packaging application.

Objects Of Invention:

The main object of the present invention is to provide a woven fabric comprises of bast fibre yam and bast compatible non bast yam produced on a flat loom machine, which is loose in weave and provides adequate aeration for storage of perishable goods.

Another objective of the present invention is to develop the woven fabric comprises of higher weight/ denier bast yam such as jute yam along with bast compatible non bast yam like polyester yam, polypropylene yam, or polyamide yam.

Another object of the present invention is to provide the woven fabric consisting of bast yam and bast compatible non-bast yam which also provides a better visual appearance and feel of bast yam fabric as compared to hitherto known fabric.

Yet another objective of the present invention is to provide a method/process for production of woven fabric from bast yam and bast compatible non-bast yam on flat loom machine.

Yet another objective of the present invention is to provide a continuous process to produce a fabric from higher weight/ denier bast yam such as jute yam along with bast compatible non bast yam without any frequent stoppage of weaving machine and at the same time preventing the formation of fluff in the weaving device and thereby also avoiding formation of wastage of bast yam.

Another objective of the present invention is to produce a fabric having improved fabric tensile properties, abrasion resistance and coefficient of friction as compared to conventional bast yam fabric and non bast yam bast compatible synthetic yam for packaging application by carrying out the weaving of the fabric on a flat weaving loom.

A further objective of invention is to provide a flexible and simple process for manufacturing variants of fabric with different weaves such as plain weave, twill weave or basket weave on a flat weaving loom suitable for packaging application at economical cost.

Summary Of Invention:

The invention discloses a woven fabric (1A) made from bast yam and bast compatible non-bast yam, its method of manufacturing and a sack/bag from such fabric. The woven fabric (1A) of invention is made from bast yam (3A) and bast- compatible non bast yam (2A, 2B) to make sacks/bags (1) for packaging applications, especially for perishable goods/commodities. A key feature of the invention is that the fabric (1A) is made using relatively heavy diner bast yam (3 A) on a flat loom. This avoids the fluff and particulate matter generated during weaving process on a circular loom, which cannot work with the heavy denier yam used in the present invention. The woven fabric (1A) manufactured using the method and materials disclosed here is more robust and durable than the fabric manufactured on a circular loom. The invention also discloses a bag (1) made from the woven fabric (1A) and a process of making a bag (1) that uses an L-stitch or a U-shaped stitch.

List of Figures:

Figure 1 shows a sack made using L-stitch from the fabrics of the present invention

Figure 2 shows a sack made using two longitudinal stitches from the fabrics of the present invention

Figure 3A and 3A1 show a fabric with plain weave with single bast yam in weft or warp directions respectively

Figure 3B and 3B 1 show a fabric with twill weave having bast yam in weft or warp directions respectively Figure 3C and 3C1 show a half basket weave having bast yam in weft or warp directions respectively

Figures 4 shows a schematic of process of making a bag from the fabric of invention Figure 5 shows a bag made using U-stitch

List of Parts:

1 - Bag

1A - Woven Fabric

IB - Woven Fabric cut piece,

1C - longitudinal edge of cut piece,

ID - transverse edge cut piece,

IE - Longitudinally folded cut piece,

IF - transversely folded cut piece,

1G - longitudinal open edge of longitudinally folded cut piece,

1H - transverse end of longitudinally folded cut piece,

II - folded end of longitudinally folded cut piece,

1 J - folded end of transversely folded cut piece,

IK - longitudinal edges of transversely folded cut piece,

1L - L-stitch,

1M - longitudinal stitch,

IN - U-stitch

2 - Warp Y am

2A - Bast compatible synthetic textured yam 2B - Bast Compatible Synthetic Composite Yam

3 - Weft Y am 3A - Bast yam

Description of the invention Fabric is a flexible material consisting of a grid of natural or artificial fibres often referred to as thread or yam. Yam is produced by spinning raw fibres such as wool, linen, cotton, or other natural or manmade material on a spinning wheel to produce long strands, or using synthetic polymer to form continuous multifilament yam such as polyester, nylon, or Polyolefin. Fabrics are formed by weaving, knitting or by non-woven techniques.

In general, the packaging fabrics are made from slit film tape of polyolefin or using natural jute. Sacking jute is rougher and heavier cloth variety of jute used mainly for storing food grains such as wheat, rice, com, pulses, and coffee beans. Hessian jute is made from finer grade jute and is lighter in weight than sacking jute and is generally used for fruits, vegetable, and product packaging.

The present invention provides a woven fabric (1A) comprising of bast yam and bast compatible non-bast yam which is produced on flat weaving loom machine. The inventors found that flat loom employs a continuous weaving process. Because the pattern of weave used on a flat loom uses yam in straight/ horizontal direction, the fluff formation is found to be substantially low primarily because of lower speed and friction in flat loom. However, at the same time, on flat loom a greater number of widths can be woven simultaneously hence the actual output per machine is higher both in terms of weight as well as width. Further, the capability of flat loom weaving of a higher weight Jute yam and minimum stoppages also results in higher productivity.

The bast yam may be selected from Jute yam, sisal yam, flax yam, hemp yam, kenaf yam, ramie yam, etc., either alone or in any combination thereof. However, for the purpose of the present invention, jute yam is preferred. Jute is preferred mainly because of the inherent properties of high tensile strength which is essential for fabric (1 A) to be used for making sacks (1). The said yam is used in the weight ratio of 50% to 80% to the weight of the fabric per unit area and higher weight ranging from 12 to 20 lbs with 2500 to 7000 denier, preferably with 4000 denier.

The bast compatible non-bast yam means a synthetic yam which is compatible with bast yam (Jute Yam) in the process of weaving on a flat loom machine and may be selected from , cotton spun yam, fibre blends in spun yam like cotton and viscose, cotton and polyester, polyester and viscose; synthetic yam like polyester, polyamide and polyolefin which may of two different forms/categories/ types based on their constmction and physical characteristics such as bulk textured yam (2A) and/or composite yam or combination thereof. However, polyester yam, polyamide yam and polyolefin yam are preferred in the weight ratio of 20 to 50%. Bast- compatible non-bast yam may be monofilament or multifilament.

Bulk textured yam (2A) is a textured bulk yam or air textured bulk yam made from multifilament yam of Polyolefins, polyester, and Polyamides to impart bulkiness to the yam and facilitate compatibility with bast yam (Jute yam). Similarly, the composite yam (2B) is made of one, two or more yams of a Multifilament/ monofilament yam which can be twisted or mingled to impart compatibility along with synthetic textured yam to the Jute yam. This also imparts the strength to the fabric (1A).

The present invention provides a method of producing/ manufacturing a woven fabric (1A) wherein a plurality of bast compatible non-bast yams aligned in Warp direction (or the first direction) and interwoven with a plurality of bast yams in Weft direction (or the second direction) content above 50% of total unit weight of the fabric.

However, in some aspects, first direction (warp) has plurality of jute yam content above 50% of total unit weight of the fabric (1A). The second direction (weft) has plurality of synthetic yams selected from synthetic yam like polyester, polyamide, and polyolefin. The term ‘yam’ as used herein is a generic term for a material suitable for weaving. For example, yams used in the present invention may include, but are not limited to monofilaments, filaments twisted or mingled together, fibres spun together or otherwise joined yams, roving yams, crepe yams, ply yams, cord yams, threads, strings, filaments laid together without twist, textured yam as well as other configurations.

The synthetic yam used has been made preferably from a texturised yam which in turn has been converted from a high denier filament yam suitable to be used in combination with Jute yam. Synthetic yam has been further improvised by incorporating of suitable additives like known Hindered Amine Light Stabilisers (HALS) UV stabilizers to withstand the vagaries of Sunlight and UV rays which deteriorates the quality of the yam.

Weaving pattern of the woven fabric (1A) of the present invention has been made in such a way that the woven fabric (1A) produced has better strength to weight ratio and is desirable to use in the direction where load bearing capacity should be higher. This also helps in the conservation/ reduction of natural yam by way of substitution by synthetic yam of much lesser weight.

The fabric (1A) of the present invention has improved fabric construction with usage of plurality synthetic multifilament yam like Polyester, Polyolefin, and polyamide in Warp (first) direction of fabric ( 1 A), whereas in the Weft (second) direction, the fabric (1A) has majority of jute yam content. This has been shown in Figures 3A,3B and 3C respectively. However, plurality of synthetic yam and jute yam can also be used in a vice versa directions. This has been shown in Figures 3A1, 3Bland 3Clrespectively.

The first direction (warp) and second direction (weft) yams are woven by having regular pattern interlacing. The interlacing of first direction and second direction yams for woven fabric (1A) formation may include but not limited to, weaves such as plain weaves, basket weaves, rep or rib weaves, twill weaves (e.g., straight twill, reverse twill, herringbone twill), satin weaves, and double weaves (e.g., double width, tubular double weave, reversed double weave), leno weaves. The woven fabric (1A) of the present invention may be made by weaving material in any suitable manner on a flat weaving loom machine that may include a table loom, a floor loom, a jacquard loom, a counterbalance loom, or a jack loom or a Projectile loom or Rapier loom. The manufacturing of said fabric (1A) on flat loom machine results into higher rate of production and low or almost zero wastages.

Method of Manufacture of a woven fabric ( 1 A) and the equipment required for it is now disclosed.

Equipment:

Warp yam supply for weaving is provided in two ways: a) directly on creel or Warping machine equipment with suitable creel to supply intended warp yam (2) for producing weaver’s beam. This beam is put on weaving machine to supply warp yam while weaving b) Weaving machine equipped with creel and tensioning device to supply warp yam (2) for weaving

Weft yam (3) supply for weaving is provided in two ways: a) Shuttled loom: Shuttle carries weft yam (3) from one end to other while weaving b) Shuttleless loom: projectile, Lens, ratrier, air jet water jet

The various steps involved in the manufacturing of the fabric made from bast yam and bast compatible non bast yam are as under:

Warp direction: Warp yam (2) consisted of synthetic composite yam and /or textured yam in predefined interval as explained in figures. Such yams have been arranged in unwinding creel of the warping machine to get the desired composition.

Weaver’s beam has been produced which has been put on the Flat weaving machine (Flat loom) for supply of the warp yam (2) during weaving.

In another case use of Jute yam as the warp yam (2), the jute package has been prepared to suit the creel of warping machine. Once Jute yam was ready for warping, weaver’s beam has been produced for supply of warp yam (2) during the process of weaving. The drawing of the warp yam (2) in the head frames has been done to achieve the required weave pattern

Weft direction:

Since warp yam (2) consisted of the synthetic yam then weft yam (3) has been of bast yam, preferably Jute yam. For shuttle looms weft have been used to be produced for supply of weft yam (3) during the process of weaving.

When Jute was used as weft yam (3), the warp yam (2) has to be synthetic yam which has been selected by the weaving machine (flat loom) in a pattern required (composite yam and textured yam). The selection of synthetic yams was carried out both electronically and mechanically for required intervals while weaving.

The presence of High weight content Jute in Warp/weft direction has been used for weaving on a flat loom in present invention in the sequential steps as explained above. The preferred weave in present case has been mostly twill weave which is not possible in case of a circular loom. The essence of the present invention is the use of high weight Jute yam in a Twill weave pattern on a flat loom which is not possible in circular loom. In a preferred embodiment, the present invention provides a method of making an woven fabric (1A) from bast yam (3A) and bast compatible non-bast yam (2A or 2B) wherein plurality of yams aligned in Warp direction (or the first direction) are interwoven with a plurality of yams in Weft direction (or the second direction) characterised in that said method comprises the steps of:

(a) providing the warp yam i - directly on weaving creel, or ii - on warping machine creel equipped with tensioning device to produce weaver’s beam which is then put on a flat weaving machine to supply the warp yam.

(b) arranging warp yam in said creels in specific arrangement to make a predefined pattern,

(c) providing the weft yam through the flat loom which transfers weft yam from one end to other for weaving the fabric, wherein weft yam may be selected from bast yam and warp yam may be selected from bast compatible non-bast yam or vice-versa in reverse direction.

The spacing of the yam (2, 3) within the fabric weave is expressed in terms of a linear density or line density of yam (2, 3) and may depend on the denier of the yam (2, 3). A higher linear density is indicative of smaller spacing between adjacent yams (2, 3). As given in Table 1 during the weaving process to create the compound woven fabric, the warp density and pick density are kept constant. The warp density may be between about 20 and 200 ends per 100 mm and the pick density may be between about 20 and 400 picks per 100 mm. An “end” refers to an individual warp yam (2), and a “pick” refers to an individual weft yam (3). In some embodiments, the compound woven fabric may consist of a balanced weave (e.g., the woven fabric of the invention has the same number of weft yams (3) per 100 mm as warp yams (2) per 100 mm. In some other embodiments the woven fabric of the invention has an unbalanced weave (e.g., the compound woven fabric may have an unequal distribution of warp and weft yams, with one or the other pre-dominating).

A bag made from the flat woven fabric (1A) of the invention is now disclosed.

A process of making a bag (1) made from woven fabric (1A) is now disclosed. The fabric (1A) is made using a method of fabric making and equipment disclosed in foregoing sections. The charactering steps of the process include first cutting the woven fabric (1A) into a cut piece (IB) of required length. The cut piece (IB) has two longitudinal edges (1C), and two transverse edges (ID). The cut piece (IB) is next folded lengthwise into a longitudinally folded cut piece (IE) having a longitudinal or side fold (II), two transverse edges (1H), and an open longitudinal edge (1G). Next an L-shape stitch or a L-stitch (1-L) is made along the unfolded or the open longitudinal edge (1G) ofthe folded cut piece (IE), and one transverse end of said longitudinally folded cut piece (1H), thereby making a bag that is stitched on its two sides - that is one longitudinal side (1G) and one transverse side (1H).

In another alternative way of the process, instead of said longitudinal fold (II), a transverse fold (1J) is made in the fabric cut piece (IB), thereby forming a transversely folded cut piece (IF) that also has two longitudinal open edges (IK). Next, a longitudinal stitch (1M) is made along each of the two longitudinal open edges (IK) of the folded fabric cut piece (IF) to make a bag open at one end. There is no bottom stitch in such a bag.

In an alternative way of the process of making a bag, instead of said L - stitch, or the two longitudinal stitches (1M), a U-shaped stitch or a U-stitch (IN) is made to cover three sides of said folded cut pieces (IF, IE), making a bag that is stitched on its three sides - that is two longitudinal sides and one transverse side. Alternatively, three separate stitches are made at three ends of said cut piece thereby making a bag that is stitched on its three sides.

Anytime a stitch is eliminated, the fabric and therefore the bag made using the fabric, becomes inherently stronger.

The preferred weaving pattern for the fabric of the present invention is now disclosed.

Fig 3A shows a fabric with plain weave with single warp. In this preferred embodiment of the present invention, the warp yan (2) and weft yam (3) direction yams are interlaced in regular pattern of each warp end passes alternately under and over each weft end, thus forming plain weave as shown in Figure 3A. This fabric (1A) is symmetrical, with good stability and reasonable porosity. Further, due to comparatively higher level of interlacement, the slightly lower mechanical properties were achieved, as desirable.

Fig 3B shows a fabric (1A) with twill weave. In this embodiment of the invention, one or more warp ends are alternately woven /interlaced over and under two or more weft ends in regular repeated manner, forming twill weave style as shown in Figure 3B. The formed fabric exhibited broken diagonal rib on surface. This kind of weave cannot be undertaken in a circular loom as disclosed in Indian Patent 357944 because of the higher weight /denier of the Jute Yam. It has been observed that use of jute yam of lower weight limits the use of circular loom especially for making weaves such as the twill weave. Therefore, woven fabric (1A) of twill weave made using a combination of high denier/weight Jute yam and Jute compatible synthetic yam made on a flat weaving machine in accordance with present invention is not possible on a circular loom machine. The woven fabric (1A) of twill weave produced using the method of the present invention has improved mechanical properties, smoother surface and enhance drape. Also, during the parkhi testing, the sacks formed using woven fabric (1A) of twill weave of the invention showed negligible hole size and better performance in terms of oozing of grains out of the fabric of the sacks. Indeed, it was found by the inventors that in present invention the weaving pattern of the bag is sufficiently loose and robust, and since higher weight Jute is used in the fabric, the chances of hole formation thereby oozing of food grains are eliminated.

Figure 3C shows a half basket weave. In this embodiment of the invention, two or more warp ends alternately interlace with one or more weft ends, in non- symmetrical or symmetrical arrangement. The woven fabric (1A) of half basket weave pattern as illustrated in Figure 3C is much stronger than woven fabric made with regular plain weave. It also helped in developing heavy weight fabric by using higher denier or thicker ends to avoid excessive interlace of ends. This type of inventive fabric showed rougher texture and better stackability.

In the woven fabric (1A) of the present invention, the warp yam (2) material has at least one characteristic, i.e., material, linear density, yam formation (twisted, mingled, etc.) that is different from the majority yams used in weft direction. The plurality of yams in warp or weft direction, or both directions, may be distributed uniformly over the surface of fabric: for example, there would be alternating jute yam group and polyester yam group, or it could be present only in few portions of the fabric, these portions possibly being longitudinal and/or transverse strips or strips spaced apart on the surface of bag (1).

Unlike the invention disclosed in IN 357944 where there is limit to the weight and density of the yams in both the directions, the present invention has uniqueness of using a high weight /high denier Jute yam and optimising the weaving pattern to get a fabric with higher gsm (grams per meter). This results in higher strength to weight ratio and a synergy has been created to achieve the desired results. Flat loom weaving is a continuous process. In case of flat loom weaving, the size of the feeding shuttle is much larger than the shuttles for a circular loom. Therefore, exhaustion of yam on a shuttle, which is small in a circular loom, results is frequent stoppages thereby affecting the rate of production. Also, the wight of yam per shuttle is lower in case of a circular loom weaving. It has been surprisingly found that a flat loom overcomes these problems and also that a Flat Loom also helps to prevent/eliminate the fluff generation which is a major problem with a circular Loom and at the same time, enhancement of productivity and quality of the fabric is achieved.

Example-1: The woven fabric of the present invention was manufactured from jute yam of 2500 denier in second direction (Weft) above 75 % by weight and first direction (Warp) has Polyester yam of 730 denier on weaving loom with the interlacing pattern for first direction and second direction yam as plain weave. The second direction has linear density of 52 picks/100 mm and first direction has linear density of 48 ends/100 mm. This arrangement resulted in required tensile strength of more than 160 kgf. Further, the bag (1) made using this fabric showed seam strength of around 52 to 54 kgf. During the Parkhi testing, there was no residual hole visible on the surface of the bag (1).

Example 2: The woven fabric ofthe present invention was manufactured from jute yam of 3500 denier above 75% by weight in second direction and first direction has recycled cotton-polyester yam of 1200 denier, on weaving loom with plain weave interlacing pattern for first direction and second direction yam. The second direction has linear density of 48 picks/100 mm and first direction has linear density of 52 ends/ 100 mm. This arrangement resulted in tensile strength of more than 140 kgf. Further, the bag (1) made using this fabric showed seam strength of around 48 to 52 kgf. And also, during the Parkhi testing, there was no residual hole visible on the surface of the bag (1). Example 3: The woven twill pattern fabric of the present invention was manufactured from jute yam of 3000 denier in second direction (Weft) above 75% by weight and first direction (Warp) has polypropylene yam of 1700 denier, on weaving loom with the interlacing pattern for first direction and second direction yam as plain weave. The second direction has linear density of 48 picks/ 100 mm and first direction has linear density of 48 ends/100 mm. This arrangement resulted in required tensile strength of more than 190 kgf. Further, the bag (1) made using this fabric showed seam strength of around 54 to 58 kgf. During the Parkhi testing, there was no residual hole visible on the surface of the bag (1).

Table 1: Properties of fabric of the present invention in comparison with (a) Jute fabric, (b) fabric of Jute yarn with HDPE yarn (c) fabric claimed in Indian patent 357944.

The fabric of the present invention has majority jute yam content in one direction and in the other direction having yams selected from one group or multiple groups like polyester and synthetic multifilament yam like polyester, polyolefin, and polyamide, resulted in having higher abrasion resistance (almost 5 to 7 times) than 100% jute content fabric.

The weaving of the fabric of the present invention cannot be achieved on any type of weaving machine except on flat loom weaving machine, however with usage of flat weaving loom it was also possible to develop different weave pattern for the above-described fabric with higher weight / denier Jute yam of the present invention and also the formation of jute fluffs resulting of higher wastage on circular machine is prevented/avoided.

For making a sack or bag (1), a fabric rolls of the present invention of about 500 to 3000 meters are made on flat weaving loom in the manner as described above. These fabric roll can be then taken through manual route of fabric cutting and bag (1) making on stitching machine. Alternatively, the fabric rolls are placed on unwinding section of specially designed bag (1) conversion machine wherein the fabric of desired length are cut by thermo-cutter and fabric cut length is passed through the folding and stitching station.

The woven fabric of the present invention can be converted into sack/bag (1). The preferred process for making of bag (1) according to invention can be carried in following manner: The woven fabric of the present invention is cut into the required length and after side way folding manually stitched in L shape or side stitch as shown in Figures 1 and 2, respectively, or U shape stitching of overlaid cut fabric pieces. Since the fabric is made on a flat machine, only L Stich is possible. In case of seamless fabric, the fabric is cut in required length and seamed to form the required end product. The final sealing of the bag at the open end is made after filling the bag using any known techniques of sealing.

The produced fabric can have desired width range from 150 to 2500 mm and bag length is as per the user demand. The woven fabric of the present invention can be used in packaging application as well as other applications like interior decoration or acoustic boards or covers.

It is evident that the invention has the following embodiments.

The preferred embodiment of the invention discloses a woven fabric (1A) having warp and weft threads (2, 3), wherein plurality of yams aligned in Warp direction (or the first direction) are interwoven with a plurality of yams in Weft direction (or the second direction. The characterising feature of the fabric (1A) is that it is made on a flat loom. Either of the weft and/or warp threads (2, 3) of said fabric (1A) are selected from a group of threads consisting of bast yam (3A) and bast compatible non-bast yam which are selected from bulk textured synthetic (2A) yam or composite yam (2B) or combination thereof. Further, the threads of bast yam (3 A) are in a weight proportion (gsm) of 50% to 80% of the weight (gsm) of the fabric (1A) and the threads of bast-compatible non-bast yam are in a weight proportion (gsm) of 20% to 50% of the weight (gsm) of said fabric (1A).

In another embodiment, the woven fabric (1A) the bast yam is selected from Jute yam, sisal yam, flax yam, hemp yam, kenaf yam or ramie yam. Preferably, the bast yam is jute yam. Alternatively, the bast yam is sisal yam. In a further embodiment, the said bast compatible non-bast yam comprises a yam selected from cotton spun yam, fibre blends in spun yam like cotton and viscose, cotton and polyester, polyester, and viscose; synthetic yam like polyester, polyamide, and polyolefin.

In yet another embodiment, the bulk textured synthetic yam is a textured bulk yam or air textured bulk yam made from multifilament yam of polyolefins, polyester and polyamides imparting bulkiness to the yam and facilitate compatibility with bast yam.

In still another embodiment, the composite yam is made of one, two or more yams of a multifilament/ monofilament yam which are twisted or mingled to impart compatibility along with synthetic textured yam to the bast yam.

In a still further embodiment, the weave of the fabric may be plain weave, basket weave, rib weave or twill weave. Preferably, the weave of the fabric is twill weave.

In another embodiment, the linear density of warp threads in the woven fabric (1A) is 20-200 ends/100 mm and that of the weft threads is 20-200 picks/lOOmm.

In yet another embodiment, the denier of jute yam is between 2500 and 7000. Preferably, the denier is 4000.

In a further embodiment, the flat loom on which the woven fabric ( 1 A) is made is table loom, or a floor loom, or a jacquard loom, or a counterbalance loom, or a jack loom or a Projectile loom or Rapier loom.

The invention has also disclosed a method of making a woven fabric (1A) from bast yam (3 A) and bast compatible non-bast yam (2A or 2B) wherein plurality of yams aligned in Warp direction (or the first direction) are interwoven with a plurality of yams in Weft direction (or the second direction). The characterising features of the method of invention are that the warp yam is provided directly on weaving creels. Alternatively, the warp yam is provided on warping machine creel equipped with tensioning device to produce weaver’s beam which is then put on a flat weaving machine to supply the warp yam. Next, the warp yam is arranged in said creels in specific arrangement to make a predefined pattern, following which the weft yam is provided through the flat loom which transfers weft yam from one end to other for weaving the fabric. It should be noted that the weft yam may be selected from bast yam and warp yam may be selected from bast compatible non-bast yam or vice-versa in reverse direction.

In an embodiment of the method disclosed here, the weft yam is provided through flat loom which may be a shuttle loom or shuttle less loom. Also, the flat loom may be a table loom, or a floor loom, or a jacquard loom, or a counterbalance loom, or a jack loom or a Projectile loom or Rapier loom. Preferably, the flat loom is a Projectile loom or Rapier loom.

In another preferred embodiment, a process of making a bag (1) made from woven fabric (1A) is disclosed. The fabric (1A) is made using a method of fabric making and equipment disclosed in foregoing sections. The charactering steps of the process include first cutting the woven fabric (1A) into a cut piece (IB) of required length. The cut piece (IB) has two longitudinal edges (1C), and two transverse edges (ID). The cut piece (IB) is next folded lengthwise into a longitudinally folded cut piece (IE) having a longitudinal or side fold (II), two transverse edges (1H), and an open longitudinal edge (1G). Next an L-shape stitch or a L-stitch (1-L) is made along the unfolded or the open longitudinal edge (1G) of the folded cut piece (IE), and one transverse end of said longitudinally folded cut piece (1H), thereby making a bag that is stitched on its two sides - that is one longitudinal side (1G) and one transverse side (1H).

In another embodiment of the process, instead of said longitudinal fold (II), a transverse fold (1J) is made in the fabric cut piece (IB), thereby forming a transversely folded cut piece (IF) that also has two longitudinal open edges (IK). Next, a longitudinal stitch (1M) is made along each of the two longitudinal open edges (IK) of the folded fabric cut piece (IF) to make a bag open at one end. There is no bottom stitch in such a bag.

In yet another embodiment of the process of making a bag, instead of said L - stitch, or the two longitudinal stitches (1M), a U-shaped stitch or a U-stitch (IN) is made to cover three sides of said folded cut pieces (IF, IE), making a bag that is stitched on its three sides - that is two longitudinal sides and one transverse side.

Alternatively, three separate stitches are made at three ends of said cut piece thereby making a bag that is stitched on its three sides.

While the above description contains much specificity, these should not be construed as limitation in the scope of the invention, but rather as an exemplification of the preferred embodiments thereof. It must be realized that modifications and variations are possible based on the disclosure given above without departing from the spirit and scope of the invention. Accordingly, the scope of the invention should be determined not by the embodiments illustrated, but by the appended claims and their legal equivalents.