US2218633A - Textile material - Google Patents

Description

Patented Oct. 22, 1940 UNITED STATES TEXTILE MATERIAL Angus Smith Bell and Joseph Rowland Wyldc,

Spondon, near Derby, England, assignors to Celanese Corporation of America, a corporation of Delaware No Drawing. Application April 5, 1938, Serial No.

4 Claims.

This invention relates to improvements in textile materials, and is more particularly concerned with new composite yarns and with fabrics or other materials made of or containing such yarns.

In recent years considerable research has been directed to the production, from artificial textile materials, of yarns which bear a resemblance to natural wool yarns. It has been found that yarns which contain short fibres of artificial textile materials, 1. e., artificial staple fibres, are of con siderable value in this connection. Such yarns may be made by spinning, in a way comparable to cotton spinning, a roving containing artil5 ficial staple fibres, or may be made by processes which comprise treating a bundle of continuous filaments of artificial material so that at least some of such filaments are broken though the continuity of the bundle as a whole is re- 20 tained. Processes of this latter type are described in U. S. Patents Nos. 2,077,078 and 2,077,- 079.

It has now been discovered that very valuable compositeyarns, having a good resemblance to 3 W001 yarns, may be obtained by associating one or more yarns containing artificial staple fibres with one or more yarns which after such association, are capable of being shrunk relative to said yarns containing artificial staple fibres, and 80 thereafter shrinking such shrinkable yarns.

The association of the yarns to form the composite yarns of the present invention may be brought about in any convenient manner. For example the different yarns may be sized to- 35 gether so that they act thereafter as a single yarn until the finished woven fabric or other material is scoured to remove the size. However, it is preferable to bring about the association of the different yarns in the composite o yarn by a doubling twist, preferably a light doubling twist.

The staple fibre yarns may have a basis of any artificial material. Thus, they may contain staple fibres having a basis of cellulose acetate 5 or other organic derivatives of cellulose or staple fibres having a basis of regenerated cellulose and produced, for example, by the viscose, cuprammonium or nitrocellulose processes. Or again, the staple fibre yarns may contain staple fibres 50 which have a basis of cellulose acetate or other organic ester of cellulose and which have been partially or completely saponified, or staple fibres which have a basis of an organic derivative of cellulose and which have been subjected to esterii ficatlon, e. g. by the processes of U. S. applica- In Great Britain April 20, 1937 tions S. Nos. 39,289 and 39,290, both filed September 5, 1935.

The staple fibre yarns may be made by any method. Thus they may be made by forming a roving of staple fibres and converting such roving into yarn. Preferably, however, the staple fibre yarns are made by the processes described in U. S. Patents Nos. 2,077,078 and 2,077,079. These processes involve causing a bundle of continuous filaments to pass between two surfaces one of which at least is a cutting surface moving at a speed different from that of the bundle, the other surface serving to press the bundle substantially at a point in its length against the cutting surface. The cutting surface may take the form of a fiuted roller as in U. S. Patent No. 2,077,079, or may be an endless cutting band as in U. S. Patent No. 2,077,078, and the pressing surface may be a stationary surface, or may be a surface, for example a roller, moving at substantially the same speed as the cut ting roller or surface as in U; S. Patent No. 2,077,078. It is a characteristic of the processes described in these specifications that the conversion of the bundle of continuous filaments into a staple fibre yarn is effected without at any stage losing the continuity of the bundle as a whole. These processes are therefore referred to as "direct conversion processes.

The shrinkable yarns may be made of any material but it is important that the shrinkable yarn associated with a particular staple fibre yarn should differ in character from the staple fibre yarn so that on treatment with shrinking agents the shrinkable yarn will shrink, whilst the staple fibre yarn remains substantially unaffected or at least shrinks only to a very small extent. This result may be achieved by employing as the shrinkable yarn a yarn which has a basis of a different material from the staple fibre yarn and/or which, by reason of its construction, is especially adapted to be shrunk, e. g. a highly twisted crepe yarn, (i. e., a yarn twisted to such a degree that it possesses the property of shrinking on treatment with hot 4 Minuteman.

below 50% acetyl content. Or, again, together with staple fibre yarn having a basis of cellulose acetate or other organic derivative of cellulose there may be employed yarn having a basis of a different derivative of cellulose, of regenerated cellulose, of cellulose acetate or other celluloseester which has been subjected to partial or complete saponification, or yarns of cotton, silk or wool.

Where, on the other hand, the staple fibre yarn has a basis of regenerated cellulose, the shrinkable yarn may, for example, have a basis of cellulose acetate or other organic derivative of cellulose or may be a silk or woollen yarn.

Where the yarn which is associated with the staple fibre yarn is a highly twisted crpe yarn it is not, in general, necessary-that such yarn should be of different material from the staple fibre yarn, since the ordinary aqueous scouring treatments which efi'ect substantial shrinkage of crpe yarns do not efiect any substantial shrinkage of the staple fibre yarns, though where the staple fibre yarns have a basis of cellulose acetate or other organic derivative of cellulose the treatment may crinkle the staple fibres, thus improving their resemblance to natural woollen fibres. The use of crpe yarns, therefore, presents the advantage that it is possible by means of them to produce composite yarns of uniform chemical character. Another way of obtaining composite yarns which have a uniform chemical character is to employ a staple fibre yarn which is naturally sensitive to shrinking agents and an ordinary yarn of the same character,

and to coat the staple fibre yarn 'with areserve, e. g., a gum, wax or starch, prior to associating such yarns together, so that on subsequent treatment with a shrinking agent the shrinking agent is prevented by the reserve from acting on the staple fibre yarn. Another process is to associate with a staple bre yam containing substantially unstretcheu artificial fibres a yarn of the same material which has been stretched to a substantial extent. In general stretched 'yarns are more sensitive to shrinking agents than unstretched yarns so that it is possible by controlling the conditions to effect substantial shrinkage of the stretched yarn without any substantial effecton the staple fibre yarn. Or, again, staple fibre yarn which contains fibres which have been shrunk may be associated with an unshrunk yarn of the same material so that on treatment with a shrinking agent the shrinking effect is restricted almost entirely to the unshrunk yarn.

It is to be understood, however, that where highly twisted crepe yarns are employed they are not necessarily made of the same material as the staple fibre yarns. Thus, very satisfactory results may be obtained by associating a cellulose acetate staple fibre yarn with a highly twisted viscose crpe yarn or a real silk crepe yarn. Where highly twisted crepe yarns havin a basis of cellulose acetate or other organic derivative of cellulose are employed they are preferably produced by processes in which twist is inserted while the yarn is under the influence of steam or hot water. For such processes reference is made to U. S. Patents Nos. 2.088.628, 2,088,587 and 2,089,191.

Where the yarn associated with the staple fibre yarn is a highly twisted crpe yarn the shrinking may be efiected, as indicated above, by the ordinary treatments with aqueous scouring liquids. However, in other cases the choice of shrinking-agent will depend on the character of the yarn to be shrunk. For shrinking cotton 'yarn or yarn having a basis of regenerated cellulose there may be employed, for example, sulphuric or hydrochloric acid, zinc chloride, thic- 'the shrinkable yarn are preferably associated together by a doubling twist. In order to obtain a fabric in which the composite yarn appears to be composed substantially of staple fibre yarn it is preferable that the denier of the staple fibre yarn should exceed substantially the denier of the yarn associated therewith. Thus, for example, a 150-200 denier staple fibre yarn may be very suitably doubled with a 50-100 denier shrinkable yarn. The staple fibre yarn may be permitted to spiral round the shrinkable yarn during the doubling operation, for example by leading the staple fibre yarn to the point where the doubling takes place under a very light tension. Thus, the staple fibre yarn may be fed to the point at which doubling takes place somewhat faster than the shrinkable yarn in order to obtain the desired spiralling effect. The staple fibre yam may be fed only. slightly faster, e. g., 5'or faster, or may be fed considerably faster, e. g., 50-100 or 200% or more faster, according to the nature of the product desired. If this spiralling effect is effected it is not so important that the denier of the staple fibre yarn should substantially exceed the denier of the yarn associated therewith.

It will be appreciated that when the yarns are associated by means of a doubling twist the individual component yarns either receive additional twist or have some twist removed therefrom, depending on the relative directions of the doubling twist and the twists in the component yarns. For this reason the twists in the component yarns should be either in excess of, or short of, that desired for them in the composite yarn produced. Thus where it is desired to produce a composite yarn in which the shrinkable component yarn is a high twist crpe yarn, it is not essential for the yarn fed to the doubling device to be itself a high twist crpe yarn if, as a result of the addition of the doubling twist, such yarn becomes a high twist crepe yarn in the product. In using high twist crpe yarns as the shrinkable yarns it is usually preferable to insert the doubling twist in the same direction as the original twistin such yarns so that at no stage have such yarns a twist higher than that desired for them in the composite yarns. For example, if an ultimate twist of 55 turns per inch in the shrinkable yarn of the composite yarn is desired, it is better to feed the yarns having a twist of 50 turns per inch to the doubling device and increase this to 55 turns per inch by a 5 turns per inch doubling twist in the same direction than to start with a yarn having an original twist of 60 turns per inch and to decrease this to 55 turns per inch by a doubling twist of 5 turns per inch in the reverse direction.

doubling twist of turns per inch, the doubling the twist in twist being in the same direction as the viscose yarn; or the product may consist of two staple fibre yarns doubled with a single shrinkable yarn, e. g., a composite yarn produced by feeding two 1'70 denier cellulose acetate staple fibre yarns (produced as indicated above) and a single 75 denier viscose yarn (hav ing a twist of about 33 turns per inch) to a doubling device, the staple fibre yarn being fed 5% faster than the viscose crpe yarn, and inserting a doubling twist of 12 turns per inch in the same direction as the twist in the viscose yarn.

However, composite ya'ns produced by doubling together staple fibre yarns and shrinkable yarns may themselves be doubled together to form heavier products and/or or may be dou bled with other yarns, e. g., other shrinkable yarns.

The composite yarns of the invention may be woven into fabrics in any suitable arrangement. They may, for example, be in the warp or weft or both in the warp and weft, and in any of these cases may be associated with yarns of any other desired character, or composite yarns containing a component having a crpe twist may alternate in the weft and/or warp with composite yarns containing crpe components of opposite twist. The invention is of greatest value in connection with the production of woven fabrics but the composite yarns of the present invention may, nevertheless, be formed into fabrics by other fabric-forming operations, for example, by circular knitting or by warp knitting.

The treatment of the composite yarns with a shrinking agent may be carried out prior to, or

subsequent to, the conversion of the yarn into fabric form.

The phrase claims is to be understood having a basis of an organic lose and also yarns having a or regenerated cellulose.

Having described our invention, what we desire to secure by Letters Patent is:

1. Process for the production of composite yarns resembling wool yarns, which comprises associating one or more yarns containing artificial staple fibres with one or more yarns which, after such association, are capable of being shrunk relative to such yarns containing artificial staple fibres, and thereafter shrinking said shrinkable yarns.

2. Composite yarns of a wool-like character containing artificial staple fiber yarns doubled with cellulosic yarns, the artificial staple fiber yarns being uniformly cockled by being present in greater length than said cellulosic yarns, and said cellulosic yarns being shrunk to a greater degree than said artificial staple fiber yarns.

3. Composite yarns of a wool-like character containingnftificial staple fiber yarns of an organic derivative of cellulose doubled with other cellulosic yarns, the artificial staple fiber yarns being uniformly cockled by being present in greater length than said other cellulosic yarns, and said other cellulosic yarns being shrunk to a greater degree than said artificial staple fiber yarns of an organic derivative of cellulose.

4. Composite yarns of a wool-like character containing artificial staple fibre yarns of cellulose acetate doubled with other cellulosic yarns, the artificial staple fibre yarns being uniformly cockled by being present in greater length than said other cellulosic yarns, and said other cellulosic yarns being shrunk to a greater degree than said artificial staple fibre yarns of cellulose acetate.

cellulosic yarns" employed in the as including yarns derivative of cellubasis of natural ANGUS SMITH BELL. JOSEPH R0 WYLDE.

CERTIFICATE OF CORRECTION.

Patent No. 2,218,655. October 22, 191 0.

ANGUS SMITH BELL, ET AL.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correctionas follows: Page sec- 0nd column, strike out lines 10 to 17, comprising claim 1 and for claims 5 and 14. read 1, 2 and 5 respectively, and that the now appearing as 2,

therein that the said Letters Patent should be read with this correction same may conform to the record of the case in the Patent Office.

Signed and sealed this 19th day of November, A. D. 191m.

Henry Van Arsdale,

(Seal) Acting Commissioner of Patents.