US2016391A - Production of artificial textile materials - Google Patents

Description

Oct. 8, 1935. R H. J. RILEY ET AL 2,016,391

PRODUCTION OF ARTIFICIAL TEXTILE MATERIALS Filed Oct. 16, 1931 s3 sa s8 T 3 Us W HM M R W w B 4 J.

E mm A mm ,0 EH T Patented Oct. 8, 1935 UNITED STATES PATENT OFFICE PRODUCTION OF ARTIFICIAL TEXTILE MATERIALS Application October 16, 1931, Serial No. 569,250 In Great Britain December 9, 1930 12 Claims.

This invention relates to the production of artificial textile materials in which a number of primary artificial filaments are caused, while in a sticky condition, to merge and coalesce under the action of pressure to form a unitary product of heavy, flattened cross-section, and is a continuation in part of U. S. application Serial No. 406,356 filed November 11, 1929.

According to the invention described in U. S.

application Serial No. 406,356, a plurality of artificial filaments in the form of long continuous lengths are rendered sticky or tacky by the application of a substance that has a solvent, restricted solvent, or softening action on the substance of the filaments, and the filaments while in a condition to adhere to each other are submitted to the action of pressure and then allowed to harden to form a single filament or strip of flattened cross-section. Pressure may be applied 20 to the whole length of the filaments to produce a ribbon, tape or straw-like product, or it may be applied intermittently to produce a product having alternating lengths of flattened and rounded cross-section.

25 The filaments to be united may be treated with the solvent or softener individually and subsequently brought together, or they may be treated while associated as a twisted or untwisted thread. The treatment may be carried out on the 30 filaments While they are travelling at any convenient stage of their production. Thus for example, the filaments may be treated continuously with their production by the dry or evaporative method or by the wet or coagulation method, and while they are proceeding to a winding or twisting and winding device, or they may be treated in the course of any bobbin-to-bobbin or similar winding or twisting and winding operation. 40 One method described in U. S. application Serial No. 405,356, for applying pressure to the primary filaments to be united, is to pass the filaments between one or more pairs of pressure rollers. One, or preferably each of the rollers is positively driven, and means are provided to enable the pressure between the rollers to be adjusted. By varying the pressure between the rollers the width of the flattened product can be ad'- justed as desired.

According to the present invention a plurality of filaments in the form of long continuous lengths while in a condition to adhere to each other are caused to pass under tension over a curved surface in such a manner that the fila- 55 ments unite and coalesce together to form a single strip or filament of flattened or straw-like cross section. When passing under tension over the curved surface, the filaments all tend to take the shortest path, 1. e., the path in contact with the surface, with the result that, whatever the nature 5 of the association of the filaments on reaching the surface, the pressure between the surface and the filaments causes the filaments to pass over the surface in the form of a flattened thread, the individual filaments of which unite to form a 1 single product of flattened cross-section, which product possesses a high degree of strength and flexibility, and a good lustre. The filaments may be passed over two or more such surfaces in turn.

The curved surface adopted for effecting flattening of the product is preferably of relatively small radius and may conveniently be provided by the use of wires, rods, or bars of round or oval cross-section, or bars having a rounded edge. The filaments are passed round one or more of such bars, rods or the like, and may make any convenient arc of contact therewith, according to the degree of flatness and the degree of coalescence required in the final product.

The filaments may be coalesced and flattened continuously with their production either by the dry or evaporative method, or by the wet or coagulation method, and while they are proceeding toa winding or twisting and winding or other collector device, or they may be treated during a bobbin-to-bobbin or other winding or twisting and Winding operation.

For example, in the treatment of filaments continuously with their production, thefilaments may be drawn from a spinning jet by means of a feed roller, at a speed greater than the speed of their extrusion, and passed from the feed roller to a Winding or twisting and winding device. Between the spinning jet and the feed roller the filaments are under tension, and, according to the invention, they may be passed over a wetting device supplied with a liquid having a solvent or softening action on the substance of the filaments, and then, while they are in a soft or sticky conolition, they may be passed at a relatively sharp angle round a wire or rod of small diameter lying at right angles to their path. Since the filaments are under tension, a substantial pressure is applied to one side of them by the wire or bar, and they are caused to coalesce into a flattened unitary product of straw-like cross-section. Alternatively, the winding or twisting and winding device may be operated to collect the filaments under tension, and the filaments may be passed round a flattening bar between the feed roller and the winding or twisting and winding device, wetting of the filaments taking place either before or after passing the feed roller. Or again, the filaments may be passed part way round the roller, round a flattening bar, and

again over the roller before proceeding to the winding or twisting and winding device.

The filaments may be treated in the manner according to the invention, otherwise than continuously with their production, for example, during a bobbin-to-bobbin winding or other operation. If it should be necessary to impart tension to the filaments for the purposes of the invention, this may be done in any convenient manner, as for example by braking the bobbin or bobbins from which the filaments are taken, or by passing the filaments through a device for imparting tension, such as a gate tension device. Alternatively tension may be imparted to the filaments whether they are being treated continuously with their production or not, by passing them successively round two rollers rotating at different peripheral speeds, so as to stretch the sticky or tacky filaments to a greater or less extent. The filaments are passed in the course of stretching, that is, between the rollers, round or partly round a Wire or bar so that the resultant product receives a flattened cross-section.

A single wire or bar of relatively small radius may be used for the purpose of the invention, or the filaments may be passed successively round or partly round two, or more bars, in order to receive an increased degree of flattening; the filaments may be re-softened between pairs of the bars if necessary. Conveniently the bars may be so arranged that the filaments pass in a zig-zag manner from bar to bar, such an arrangement of bars imparting tension to the filaments in a similar'manner to the gate tension device above referred to. If desired, means such as a roller or a weight or spring-pressed finger may be employed to assist the flattening of the filaments as they pass over the curved surface. The fiattened product may, moreover, be passed though further pressing means such as rolls, either with or without further softening.

' The solvent or softener may be applied by spraying or immersing the filaments or' by passing them over rollers, rods, wicks, or other devices moistened with the substance or material. Such devices are particularly advantageous in applying liquid to the filaments in a controlled manner, in justthe amount necessary to produce the degree of coalescence and flattening desired. Thus, a sufficient quantity of solvent may be applied to produce a'unitary filament which is thoroughly coalesced, and is homogeneous in cross-section, or a limited amount of solvent may be applied to produce mere superficial softening of the filaments, so that the final product retains in its structure the fibrous qualities of the individual filaments, and is of increased flexibility and strength. The solvent or softener may also be used in the form of vapour through which the filaments are passed. Further, the filaments may be subjected to the flattening pressure while they are in a sticky or tacky condition by reason of residual solvent when the treatment is carried out continuously with their production. Further, substances may be added to the spinning solution to maintain the filaments stick or tacky for a sufficiently long period. For example, vinyl acetate may be added to solutions of cellulose acetate or other organic derivatives of cellulose in solvents such as acetone. Heat may also be employed in bringing thermoplastic filaments to a sticky or tacky condition, as by heating the wires or bars. Any residual stickiness inthe flattened products may be removed by treating them with suitable substances, such as lubricants.

If desired means may be provided for causing the width of the product to vary. The width of the product depends in general upon the softness of the filaments, the number of bars, rods or wires round which they are passed, the diameter of such rods or wires, the angle of the arc of contact made by the filaments thereon, and the tension under which the filaments are travelling. Any of these factors may be varied or adjusted to give varying or any desired constant width to the product. Particularly however, the number of rods and the arc of contact made on them by the filaments are factors which are readily susceptible to adjustment. Thus for example, the number of parallel rods in the form of a gate may be carried by two members at right angles to the rods, alternate rods being connected to each member. The filaments may now be passed between the two sets of rods, and if the members of one set are passed between the members of the other set the filaments will pass over and under the rods of the two sets in a zig-zag manner. The distance between the two sets may then be adjusted, and the arc of contact made by the filaments with each rod may be varied. Further, by

inclining the two sets of rods at an angle to each other, the rods may be brought into operation upon the filaments not simultaneously but one after the other so that the number of rods acting on the filaments and the arcs of contact made by the filaments thereon are varied simultaneously. The invention is particularly applicable to the treatment of artificial filaments having a basis of cellulose acetate or other cellulose derivatives, whether produced by the dry or evaporative method or by the wet or coagulation method, and whether during the course of such production or subsequently thereto. Examples of other cellulose derivatives which may form the basis of the filaments are cellulose esters, e. g., cellulose fo-rmate, propionate, and butyrate, and nitrocellulose; cellulose ethers, e. g. methyl, ethyl, and benzyl cellulose; and the condensation products of cellulose and glycols and other polyhydric a1 cohols. Gther types of artificial filaments may likewise be treated, either while they are capable of adhering to each other during their production or by the use of appropriate softening materials.

Solvents, suitable for use with filaments of cellulose acetate or other organic derivative of cellulose are lowrboiling solvents such as acetone (commercially pure, or mixed with water) ethylene dichloride and ethyl or methyl alcohol, dichloroethylene and ethyl or methyl alcohol etc., medium or high boiling solvents or plastifiers such as diacetin, triacetin, ethyl lactate, diacetone a1- cohol (alone or mixed with water or alcohol) dibutyl tartrate or tricresyl phosphate, and mixtures thereof. The use of high boiling solvents or plastifiers imparts increased pliability to the product; When a volatile solvent such as acetone is employed, means may be employed to assist its evaporation from the filaments after the pressure has beenapplied, and, if desired, such means may be associated with an apparatus for the recovery of the solvent. Such solvents or softeners as are not removed by evaporation may if necessarybe ,provided with braking devices I4.

ing,or may be allowed to remain in the products.

If desired, dyes or other colouring matter may be applied to the filaments which are to be united and flattened. For example, the solvent or softener may have incorporated therein a dye, or metallic or other coloured powder which is thus applied to the filaments simultaneously with the solvent or softener. Further, striped effects may be produced by uniting coloured filaments or by introducing coloured or uncoloured filaments, yarns, or-threads of the same or other material into the number of filaments to be united. For example, filaments of reconstituted cellulose such .as viscose may be associated with filaments of cellulose acetate to give a flattened product capable of receiving cross-dyed effects. Fine metallic wires or ribbons, such as tinsel, may also be incorporated in the flattened product.

The ribbon or other product may be wound or otherwise collected after treatment.

The ribbons, tapes, or straw-like products manufactured according to the present inventionmay be woven or otherwise formed into fabrics or articles, and are capable of wide use, for example,

in millinery and as insulation for electrical purposes.

The invention will now be described in greater detail with reference to the accompanying drawing. It is tobe understood, however, that the following description is given by way of example only and is in no way limitative. I

Fig. 1 shows a method of carrying out the invention during a bobbin-to-bobbin winding o-peration I Fig. 2 is a detail of Fig. 1;

Figs. 3 and 4 are a plan and side elevation respectively, showing another manner of carrying out the invention.

Figs. 5, 6 and 7 are details of the operation shown in Figs. 3 and 4.

Referring to Fig. 1, a number of threads II of continuous filaments are taken from a series of bobbins I2 mounted in a creel I3 and each From the bobbins I2 the threads II are passed through a collecting device, such as a reed, which disposes the threads in an orderly arrangement, or, as shown, a die I which gathers them into a single thread I6, and proceeds thence to a moistening device I1, hereinafter to be described with reference to Fig. 5. In their passage through the moistening device Ii, the filaments are moistened with a solvent or softener such as a mixture of acetone and water, ethylene glycol and ethyl ,sectie-n of the bars I8, I9 is clearly shown in Fig.

2 and it will be perceived that the edge 25 of the bar is rounded to a curve of a very small radius, the cross-section of the bar approximating more or less to that of a knife edge.

a After passing the bars It, I9, the filaments proceed round a roller 2i mounted on a shaft 22 and provided with a back guide 23. A long run is preferably provided for the filaments between the knife edges I8 and the roller 2| to allow the filaments to dry, and if desired, to economize 70 in floor space, the filaments may be caused to follow a path vertically up and down for this purpose, as will be readily understood. The rotation of the roller 2| draws the filaments from the bobbins I2, past the die 45, moistening device I1 and bars I8, I9 and, since the bobbins I2 are braked by means of the device I4, some degree of tension is imparted to the filaments while they are passing'the knives l8, I9. The tension causes all the filaments to try to pass as closely as possible to the knife edge 20 so that they merge and unite together to form a, unitary product of flattened cross-section. After passing round the roller 2| and back guide 23, the unitary product is collected on a bobbin 24 frictionally driven by means of a roller or the like 25 which makes slipping contact with the flanges 26 of the bobbin 24.

In Figs. 3 and 4 a method of carrying out the operation continuously with the production of the filaments is shown. The filaments are produced by the extrusion of a spinning solution from a spinning nozzle 36 disposed in a spinning cell 3|, the filaments 32 passing down the cell and through the opening 33 at the lower end of the cell as a thread 34. A number of such threads 34 are passing over a feed roller 35 and through separate back guides 36 and are collected together by means of a collecting die I5, passing therefrom as a single thread I6 to the moistening device H, from which they receive a quantity of solvent or softening material. After passing the moistening device I1, the filaments pass over and under a series of rods 31, 38 disposed in the form of a gate tension device 39 which is showndiagrammatically in Figs. 3 and 4, and in greater detail in Figs. 6 and 7. The filaments turn sharply round the curved surfaces of the rods 31, 38, endeavoring to take the shortest path, and thereby being caused to coalesce and merge together to form a product of flattened cross-section. If desired the flattened product 40 may be passed round a further roller 4| shown in Fig. 4, the roller 4! being caused to rotate at a higher speed than the roller 35 in order that any desired degree of tension may 40 be imparted to the filaments as they pass through the tension device 39. The flattened product 40 passes by way of a traversing guide 42 mounted on a traversing bar 43 to a bobbin 44, driven by means of discs 45 which are in slipping contact 45 with its flanges 46, so that the flattened product is collected on the bobbin 44 as fast as it is produced.

Further filamentary materials may be introduced into the product in the manner shown in Fig. 4, filamentary material 41 from a bobbin 48 being passed through the die I5 with the filaments 34. Further, if other eifect materials such as dyes, pigments or metallic or other powders and dyes are required, they may be applied by means of the wick I! or by means of a further wick of a similar kind, or by means of any other applying devices.

Fig. 5 shows a moistening device of the form described in U. S. application Serial No. 538,484 filed May 19, 1931, for applying a solvent or softening material to the filaments. Crossed levers 50 are mounted on a common pivot 5I. clipped to the upper, vertical ends of the levers 55 by means of clips 52 are wicks 53, which dip into a solvent or softening liquid 54 contained in a vessel 55. On the horizontal extremities 56 of the levers 50, weights 5'! are mounted in order that the wicks 53 may be pressed together between the ends of the levers 5!]. The members in which the pivot 5| are carried project upwardly on each side of the wick to form a V guide 58 which guides the thread 59 between the' surfaces of the wicks 53, which are therefore pressed together by the weights 51 on to the thread. The whole moistening device is clipped to the top of the vessel by means of a clip 69.

In Fig. 6 one form of tension device shown at 39 in Figs. 3 and e is illustrated. Three fixed bars or rods 6i are mounted on a common member 62 to which is pivoted at a point 63 two curved members 64, 65. The members 64, @5 are raised and lowered at intervals by means of a cam 66 rotated on a shaft El and operating upon a bowl 68 carried by an extension of one of the rods 69. It will be seen that the two curved rods 64, 65 are mounted so that one is higher than the other and so that the rod E54 comes into operation first and causes the thread to turn at a sharper angle than the rod 65. By means of a tension device of this character a product of irregular width may be produced, having if desired, lengths of unitary product alternating with lengths of threads consisting of a number of separate filaments. The rods E54 and 655 are curved in order that the filaments may take up a definite position when passing between them, and may not ride out of engagement with the tension device. In order to prevent the filaments from slipping out of the end of the device the ends it of the rods are curved downwardly.

In Fig. 7 a simple form of tension device is shown in which the two curved bars 6 3, 65 are at the same level. This device is adapted to be set by hand by means of a handle ll and a wing nut 7 12 in order to produce flattened unitary product of any desired constant cross-section.

What we claim and desire to secure by Letters Patent is:

1. Process for the manufacture of unitary products from a number of artificial filaments having the form of continuous lengths which comprises positively moving said filaments, while in contact with each other and of a mutually adhesive nature and in a state of tension, relativelyto and in contact with a substantially straight edgehaving a curved surface, whereby they unite and coalesce to form a product of flattened cross-section.

2. Process for the manufacture of unitary products from a number of artificial filaments having the form of continuous lengths which comprises positively moving said filaments, while of a mutually adhesive nature and in a state of tension relatively to and in contact with a curved surface, whereby they unite and coalesce to form a product of flattened cross-section, including the step of varying the cross-section of the product by varying the total thrust between the filaments and the curved surface.

3. Process according to claim 2 including the step of providing more than one curved surface in order to increase the Width of the product.

4. Process according to claim 2 including the step of varying the cross-section of the product by varying the arc of contact between the filaments and the curved surface.

5. Process according to claim 2 including the step of varying the cross-section ofthe product by varying the tension in the filaments.

6. Process according to claim 1, including the step of imparting a mutually adhesive nature to the filaments to be treated by applying heat thereto.

7. Process for the manufacture of unitary products from cellulose acetate and other cellulose derivatives which comprises extruding a solutionthereof into an evaporative atmosphere to 'them, in a state of tension, relatively to and in contact with a substantially straight edge having a curved surface, whereby they unite and coalesce to form a product of'fiattened crosssection.

8. Process for the manufacture of unitary products from cellulose acetate and other cellulose derivatives which comprises extruding a solution thereof including vinyl acetate into an evaporative atmosphere to form continuous filaments, removing by evaporation the solvent from said filaments, and thereafter uniting said filaments, while of a mutually adhesive nature by virtue of their content of vinyl acetate, by positively moving them, in a state of tension, relatively to and in contact with a curved surface, whereby they unite and coalesce to form a product of flattened cross-section.

9. Process for the manufacture of unitary products from artificial filaments having the form of continuous lengths which comprises positively moving a number of said filaments, together with filaments of contrasting material, While in contact with each other and of a mutually adhesive nature and in a state of tension, reiativeiy to and in contact with a substantially straight edge having a curved surface, whereby they unite and coalesce to form a produc of fiattened cross-section. a

10. Apparatus for the manufacture of unitary products of flattened cross-section from a number of artificial filaments comprising means for applying a solvent or softening material to the filaments to impart to them a mutually adhesive nature, a member having a substantially straight edge havinga curved surface of small radius, and a feed device for positively moving said filaments while in contact with each other, under tension, relatively to and in contact with said curved surface.

11. Apparatus for the manufacture of unitary products of flattened cross-section from a number of artificial filaments of contrasting kinds comprising a plurality of filament-supplying devices each supplying at least one filament of one kind, the filaments supplied being of a mutually adhesive nature, a member having a sub stantially straight edge having a curved surface of small radius, and a feed device for positively moving said filaments while in contact with each other, under tension, relatively to and in contact with said curved surface.

12. Apparatus for the manufacture of unitary products of flattened cross-section from a number of artificial filaments of contrasting kinds comprising a plurality of filament-supplying devices each supplying at least one filament of onekind, means for applying a solvent or softening material to the filaments to impart to them a mutually adhesive nature, a member having a substantially straight edge having a curved surface of small radius, and a feed device for positively moving said filaments while in contact with each other, under tension, relatively to and in contact with said curved surface.

REGINALD HENRY JOHN RILEY. THEODORE CLIFFORD BARNETT.

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