US 2472512 A
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June 7, 1949. A. P. BENTHALL BLANKETS, BLANKET MATERIAL, FELT SUBSTITUTES, AND CARPET MATERIAL Filed Nov. 27, 1944 b (w ool lenised before weaving) INVENTOR. ARTHUR PAUL BENTHALL,
e wtk Attorney Patented June 7, 1949 BLANKETS, BLANKET MATERIAL, FELT SUB- STITUTES, AND CARPET MATERIAL Arthur Paul Benthall, Calcutta, Bengal, British India, assignor to Bird & Company, Calcutta, Bengal, British India, a partnership firm Application November 27, 1944, Serial No. 565,432 In British India January 15, 1944 4 Claims. 1
This invention relates to a mercerised or woollenised jute fabric. The fabric so produced may be so formed as to be suitable for use as blankets, blanket material, carpet or like material or as a substitute for felt.
It has long been known that mercerisation (treatment with strong caustic) of jute ,fibre tends to give it a softer and a somewhat woollike character. A process based on this knowledge has been used in Europe for treating jute fibre and subsequently bleaching it before incorporating with ordinary wool in the manufacture of mixed wool-jute fabrics.
In my co-pending U. S. patent application Ser. No. 565,433, filed on even date herewith, I have described a process for making a jute fabric which consists in weaving a jute cloth using a hard-spun, relatively thin but strong warp and a relatively thick, loosely-spun weft (for example of rove twist) and passing the so-woven cloth through a bath of caustic, or otherwise treating it with caustic, to mercerise and/or woollenise the fabric, washing out the excess caustic and submitting the surface of the cloth to a nap raising process.
The present invention has for its object to produce a similar kind of jute fabric for blankets, blanket material, carpet material and felt substitutes but by a somewhat simpler and more economical method.
An object of this invention is to treat the weft threads only with caustic instead of treating the cloth in the piece with caustic or the like.
The advantages which result from treating the weft threads with caustic or treating solution before weaving rather than treating the woven cloth with caustic are:
(a) The treatment is easier.
(b) The treatment prior to weaving of the weft threads to mercerise them eliminates largely the shrinkage of the cloth which is ordinarily due to the application of a mercerisation process to the cloth in the piece.
Narrower looms may thus be used in weaving as the same shrinkage need not-be allowed for.
(d) As the treatment with caustic is confined to the weft threads alone the caustic consumption is reducedand also the treatment is concenrated on those parts which need the treatment.
The process employed in accordance with this invention is not merely a process of-simply mercerising jute or producing a jute cloth, but is a process in which the relationship of the twist of l are of considerably greater bulk than the warp threads, and if the warp threads were of the same nature as the weft threads it would be difficult, if not impossible, to weave the cloth, and'if the weaving could be accomplished the cloth would be too weak.
One object of the invention is thus to start with warp threads which are hard-spun, thin and strong and which may indeed be harder spun and stronger than the warp threads which are generally used. The weft threads, on the other hand, are relatively thick and loosely spun, bulking for the weight of fibre therein, considerably larger than the warp threads. In fact the weft threads may be of rove twist and for equal weights of fibre have twice, or more than twice, the bulk of the warp threads. With the larger bulk of the weft threads, they will more effectively cover over the warp threads when the woven cloth is made, so that the exposed surface of the woven cloth will practically all be of the thicker and looser weft, and it is this part, viz: the surface of the weft threads, which is subsequently nap raised to make 'a blanket-like surface, which has the appearance of wool.
One advantage in making the weft threads thick and loosely spun is that they can then more readily be attacked by caustic tomercerise and to woollenise the same.
The chemical treatment of the yarn forming the weft threads or the treatment of the weft threads themselves, consists in immersing them in a caustic solution, for example a caustic soda solution of 10 to 15% strength, until suificient mercerisation is achieved.
This willv usually take place in about 5 to 20 minutes, depending on the character of the jute fibre, the twist in the yarn, the caustic concentration and the temperature.
On the accompanying sheet of drawing, the single figure shows diagrammatically, in top plan view, a portion of a fabric according to the invention.
The preferred procedure in producing such a fabric according to the invention envisages a continuous process in which the yarn or the weft threads pass through a shallow caustic bath which is kept up to a given strength by circulation through an outsid replenishing. Preferably the caustic leaves the mercerising bath at the point where the lute fibres enter the bath thus passing through the bath in the counter-flow direction to the passage of the fibre.
As the yarn or weft threads leave the bath, they may pass through heavy squeezing rollers which remove most of the free caustic therefrom and return it to the bath. The yarn or weft threads are then washed, preferably in hot water, to remove the remaining caustic. In a preferred arrangement, the first washes will go back to the main caustic tank, where the concentration is kept up by the addition of strong caustic from time to time.
When the yarn or the weft threads is, or are, freed from caustic by washing, they are given a final wash with soap and water. At this stage mangling or mechanical treatment may be given to the weft threads accompanied by the addition of a certain amount of oil or softening emulsion further to soften the fibre. The weft threads may then be dried out and are ready to be used in weaving the cloth, the warp threads in which cloth .will be of the harder-spun, stronger type which have not been treated with caustic.
If desired, mercerlsin machines may be used for mercerising the yarn or the weft threads.
Instead of the mangling and softening being effected on the weft threads before weaving, this part of the process may be delayed until the weaving of the cloth is completed and the cloth, in the piece, then be subjected to mangling or mechanical treatment accompanied by the addition of oil or softening emulsion further to soften the fibres. The cloth is finally subject to a "nap raising treatment.
If it is desired to dye the material to any dark shade, the dyeing operation would preferably be carried out immediately preceding the softening and mangling process on the cloth and before the final drying and "nap raising.
These jute fabrics, after the finishing and nap raising have rather a pleasing yellow-brown shade, not unlike that of a camel-hair blanket.
The invention consists in a process for producing a, mercerised and/orvwoollenised jute fabric suitable more particularly for blankets, blanket material, carpet or like material, or for a substitute for felt, which comprises using a thin wellspun warp, which has not been mercerised or greater than that of, or is at least twice the visual bulk of, the more tightly spun warp threads prior to weaving and prior to the treatment of the weft threads with caustic or with mercerising agents;
In this process the weft threads, before weaving, may be treated with caustic of such a strength and for such a period as to mercerise or partly to mercerise and to woollenise the said threads. These weft threads or the yarn for producing them, may be treated with caustic solution of any desired strength; but a caustic solution of 10 to 15% strength has been found very satisfactory. The caustic may be applied to the weft threads for the desired length of time according to the results which it is required to obtain; but it has been found that the caustic may conveniently be applied for a, short period of time only, for example for a period of from a few minutes to about half an hour dependent upon the results required. For example, the caustic treatment may be effected for from 5 minutes to 20 minutes.
In treating the weft threads before the weaving, these weft threads preferably are passed through a bath of caustic in which they meet the caustic moving in counter-flow to the direction of movement of the weft threads through the bath.
The strength of the caustic in the treating bath may be kept up to a desired degree by continuous treated with caustic to woollenise or process the same, and a weft more loosely spun than the warp, which weft has been mercerised or partly mercerised by treatment with caustic or mercerising agents, weaving the fabric with the said warp and weft, and subsequently subjecting the fabric to a nap raising" process.
The invention also includes a process for producing a woollenised or more or less mercerised jute fabric having, as finished, the form or appearance of a blanket, blanket material or felt substitute, in which a relatively thin but strong warp is used and a relatively bulky or more loosely spun weft, and wherein the weft threads, or the yarn for producing them, only are treated with caustic woollenise or process the same prior to the weaving, the weaving of the cloth is effected, and the woven cloth is subsequently subjected to a nap raising process.
Either process may be one in which the visual bulk of the loosely spun weft threads is much or intermittent additions of caustic to the bath.
The weft threads, after passing through the caustic bath, may be passed through rollers to squeeze out caustic from the threads. The caustic squeezed out of the weft threads may be returned to the caustic bath or returned to storage tanks.
According to a preferred method, the weft threads, after treatment with caustic, are washed and the first washings are returned to the caustic bath to be mixed with fresh strong caustic therein. Alternatively, the washings may be returned to the recovery plant for the recovery ofcaustic therefrom.
The weft threads are preferably washed in hot water and/or with soap and water after passing through the caustic bath.
According to the preferred embodiment, the weft threads, after treatment with caustic, and/ or after subsequent washing, are subjected to a mangling or mechanical treatment accompanied, if desired, with the addition of oil or emulsion further to soften the weft threads before they are used in the weaving of the cloth.
Alternatively, the cloth after weaving is subjected to a mangling or mechanical treatment accompanied, if desired, with the addition of oil or softening emulsion further to soften the fibre.
The process thus is one wherein shrinkage of the cloth is more or less completely prevented by treatin the weft thread before weaving to mercerise or woollenise them to a desired extentwhereby the shrinkage in these threads is effected before weaving and wherein the cloth after weaving is substantially free from shrinkage.
The process is also one wherein the amount of caustic which is required to produce a desired mencerisation or woollenisation effect on the cloth is reduced to a minimum by only treating the weft thread and not the warp thread and the weaving is so performed that the surface of the cloth is nearly wholly constituted by the weft threads and the greater part of the bulk of the cloth is made up of such weft threads.
The cloth may be woven in any desired manner, for example an ordinary plain weave or a twill weave may be used. However, it is preferable to use a broken twill weave, although this is not by any means essential.
As may be seen from the figure of drawing on the accompanying sheet of drawing, the fabric according to the invention, in ordinary plain weave, may comprise hard spun, thin and strong warp threads shown at a and relatively thick and loosely spun pre-woollenised spun weft threads shown at 1).
According to this invention the cloth is subject to a nap "raising process applied to one or to both sides of the cloth.
Theinvention not only includes a process of manufacture but it also includes a woollenised or mercerised jute fabric or a .jute fabric which is .inj'the forin of a-blanket, blanket material; felt substitute or carpet material, when made in accordance with a process as hereinbefore indicated.
It will be understood that the mercerisation by treatment with caustiomay be applied to the yarn for producing the weft and when in the claims treatment of such weft threads is referred to it is to be understood that this treatment may be applied to the material of the weft threads at any time prior to the actual weaving of the cloth.
1. A chemically woollenised or woven jute fabric having a thick and loosely-spun jute weft and a thin and hard-spun but otherwise untreated jute warp, the bulk of the weft being considerably greater than that of the warp, said weft having been substantially completely woollenised prior to weaving, whereby the surface of the fabric is constituted primarily of woollenised weft.
2. A chemically woollenised woven jute fabric having a thick and loosely-spun jute weft and a thin and hard-spun but otherwise untreated jute warp, the bulk of the weft being considerably greater than that of the warp, said weft having been substantially completely woollenised prior to weaving, whereby the surface of the fabric is constituted primarily of woollenised weft, the weave of the fabric being a broken twill weave.
3. A chemically woollenised woven jute fabric having a thick and loosely-spun jute weft and a thin and hard-spun but otherwise untreated jute warp, the bulk of the weft being considerably greater than that of the warp, said weft having been substantiallycompletely woollenised prior to weaving, whereby the surface of the fabric is constituted primarily of woollenised weft, the bulk of the weft being, for equal weights of'fiber, at least twice that of the warp.
' 4. A chemically woollenised woven jute fabric having a, thick and loosely-spun jute weft and a thin and hard-spun but otherwise untreated jute warp, the bulk of the weft being considerably greater than that of the warp, said weft having been substantially completely woollenised prior to weaving. whereby the surface of the fabric is constituted primarily of woollenised weft, and at least one side of the fabric having a raised nap.
ARTHUR PAUL BENTHALL.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED s'rA'rEs PATENTS