US2131810A - Treatment of cellulose derivatives - Google Patents

Description

Oct. 4, 1938. E. KINSELLA ET AL 2,131,810

TREATMENT OF CELLULOSE DERIVATIVES Filed Sept. 30, 1950 2 Sheets-Sheet 1 1\ a My EDWARD 'KINELLA ROBERT E RUBERTS ENT S NV way.

ATTQRNEYS Oct. 4, 1938. E. KINSELLA ET AL 2,131,810

TREATMENT OF CELLULOSE DERIVATIVES Filed Sept. 50, 1950 2 SheetsSheet 2 EDWARD KINSELLA JOSHUA BOWER ROBERT P. RUBERTS JOHN F'- BRiGGS IK ENTOHS Patented Oct. 4, 1938 2,131,810 TREATMENT or CELLULOSE DERIVATIVES Edward Kinsella, Joshua Bower, John Frederick Briggs, and Robert Pierce Roberts, Spondon, near Derby, England, assignors to Celanese Corporationof America, a corporation of Delaware Application September 30, 1930, Serial No. 485,410 1 In Great Britain October '7, 192 9 x v l Claims.

This invention relates to the manufacture of artificial silk and other filaments or'threads from solutions of cellulose acetate or other cellulose derivatives, particularly. by the dry or evaporative method, and is an improvement in or modification of the invention described in U. S. applica tion 'No. 332,907 filed August 2nd, 1929.

According to a process for the production of artificial filaments or threads described in the said specification, a spinning solutionis extruded into a spinning 'cell or chamber through'which fiows an evaporative medium in counter-current to the direction of flow of the filaments or threads and an additional evaporative medium is introduced into the said current in the vicinity of the jet- The additional medium is preferablydirected towards the, filaments as they issue from the jet.

'Ihe'introduction of evaporative'medium in this manner enables the uniformity and character of thefilaments or threads, to be controlled to a high degree.

The present invention has for its object to enable evaporative medium .so introduced to be.

brought into even closer proximity to the filaments issuing from the spinning jet. It will be understood that where, for example, a line jet is employed no difiicultyis experienced in projecting, according to the prior invention, evaporative medium on to the filaments from bothsides. In the case, however, of jets having their spinning orifices arranged in the form of rings or other closed or partially, closed figures the evaporative medium can only be directed towards the outside of the circular, part-circular, or similar bundle of filaments when the medium is introduced by devices having a discharge orifice or orifices disposed outside the bundle of filaments.

According to one feature of .the present invention the additional medium is introduced to the inside of a bundle of filaments in the vicinity of l the spinning jet. The whole, of the additional medium may be introduced into the cell in this manner, or such introduction may be used in conjunction' with the introduction of additional medium to the outside of the bundle of filaments.

In one method of carrying out this feature of the invention, the additional medium is introduced through the plane of the jet. Thus, the disc-type jet commonly employed may be replaced by an annular jet,,the central hole of whichserves as an inlet for the additional medium or through which a pipe or jet for introduci ng the additional medium can pass to the also be employed, the central opening of the jet readily permitting the introduction of the additional medium in any desired manner.

A further method of carrying out the introduction consists in employing a spinning jet in which instead of a complete circle or closedfigure of orifices a partially'closed circle or figure is employed. A gap is thus left in the bundle of filaments as they are spun from the jet and through this gap there is inserted a pipe or jet by means of which evaporative medium is directed to the inside of the bundle. V, The pipe or jet may he slid or swung into position after extrusion of the filaments has commenced, a stop being provided to control the position of the pipe or jet inside the bundle. A spring catch maybe fitted to secure the pipe or jet in place, or other means may be adopted for the same purpose.

The medium introduced by the pipe or jet may:

be directed in any desired direction with respect to the filaments, for example, downwardly, up-

wardly, or radially outwards, but preferably in the direction of movement of the filaments an somewhat outwardly.

A further feature of the invention consists in constraining the additional medium introduced:

into the cell or chamber in such a way that it is caused to flow through a tubular or other collector device that surrounds the filaments, the additional medium thus being brought into intimate contact with the filaments. The flow of the additional medium through the collector device may be in the same direction as that in which the filaments are moving, or opposite thereto, the

position of the device for introducing the medium with respect to the collector device and the manner in which the device discharges the medium being so arranged as to assist the flow of the medium in the desired direction.

The invention is applicable to any dry spinning process in which the evaporative medium flows in counter-current to the filaments. For example, it may be used in connection with dry spinning processes in which spinning solution is extruded downwardly into an upwardly moving current of evaporative medium, or upwardly into a downwardly moving current.

The amount of additional evaporative medium introduced may bear any desired relationship to the total volume of evaporative medium passing through the cell. In order that this proportion may be regulated, it is preferred that the pipe, tube, conduit, or other means employed for supplying the additional medium should be provided with control means, such as are described in U. S. Patent No. 1,541,104 with reference to the draw-off from the cells. The draw-off from the cells is preferably controlled in a similar manner, and where an installation comprises a number of cells or chambers, each should be fitted with control means for the supply of additional medium, and for the draw-off, so that all the cells may operate under similar uniform conditions. By means of the close control described, the additional medium may be introduced in relatively small or relatively large proportions.

The medium introduced into the vicinity of the jets may be heated before its introduction, and any suitable means may be employed to impart the desired degree of heat thereto, but, on

the other hand, cold or comparatively cold medium may be introduced into the cell if desired.

If desired the additional evaporative medium may contain a proportion of solvent or other vapours, introduced for example by simple admixture therewith, or by passing the medium through a moistening chamber or by mixing it with solvent laden medium, for example. solvent laden medium withdrawn from the cell.

The invention will now be described in greater detail with reference to the accompanying drawings, but it is to be understood that this description is given by way of example only and is in no respect limitative.

Fig. 1 is an elevation, partly in section, of a spinning jet fitted with means for introducing additional medium inside the bundle of filaments;

Fig. 2 is a diagonal section of part of the jet; and

Fig. 3 is a plan View.

Fig. 4 is a sectional View of a spinning cabinet showing the jet in operation.

Fig. 5 is an elevation of a further form of means for introducing additional medium to the inside of the bundle of filaments; and

Fig. 6 is a view from beneath of the spinning jet shown in Fig. 5.

Figs. 7, 8 and 9 are sectional views of spinning cells in which the means for introducing additional medium are used in conjunction with collector devices surrounding the filaments.

Referring to Figs. 1-4, a spinning jet comprises a square body I, the lower part B of which is cylindrical in shape and screw threaded. A cylindrical space 9 in the body to which spinning solution is supplied communicates by means of four passages I0 with an annular space H on the lower face of the body 1. Into a central recess l2 in the lower face of the body 7 is fitted a member l3 which is held in place by means of set screws M. Against the face of the jet body 1 are placed a piece of filter cloth i5 and an annular jet it, together with suitable packing H.

The holes E8 in the annular jet fall under the.

annular space H in the jet body 'I. The jet is, together with the packing and filter cloth, is held in place by a nut l9, screwed on to the lower half 8 of the jet body '5, and by a member 29 passing through the centre of the jet and screwed in to the member 13. The member 29 is provided with hexagon faces 2! so that it may readily be gripped for screwing in place.

The spinning solution is supplied under pressure to the space 9 and passes down the passages H) to the annular space I I and through the filter cloth l5, emerging from the orifices l8 in the annular jet I6 in the form of a circular bundle of filaments 3! completely surrounding the member 29.

Referring to Fig. 2, the recess I2 communicates by means of an oblique passage 22 with a pipe 23 connected to a source of air under pressure. The air passes to the recess [2 and down a passage 26 in the member 20, then spreading over a cone shaped part 25 of the member 20 to pass out uniformly from all sides of the member 2%) to the inside of the bundle of filaments 3!, its passage being controlled and directed by an adjustable spreader 26, screwed into the member 28]. The air emerges in a downward and outward direction, as shown by the arrows in Figure l. The whole jet is attached by means of screwthreads 21 to the spinning solution supply pipe 23 in the spinning cabinet 29.

Beferring'to Figs. 5 and 6, a disc jet 36 secured to a nut 35 by a nut 31 has a number .of orifices 38 disposed in the form of a horse shoe, thus causing a gap to be formed on one side of the bundle of filaments 3!. To the supply pipe 28 is secured an attachment 39 adapted to support a clip 48 carrying an air pipe Al to which air is supplied through a flexible connection 42. The clip 40 swings about a pivot 43, a lug 44 on the part .453 limiting the clockwise movement of the clip and pipe. Attached to the end of the pipe ii is an air jet 45, the pipe 4| being so bent, that when the pipe is in its operative position as limited by the lug M, the air jet 55 is surrounded by the filaments 3i issuing from the jet orifices 38. Ai supplied to the pipe 4! emerges through a series of holes in the jet 35 to the inside of the bundle of filaments. When the pipe 4! is swung back the air jet #5 passes through the gap 46 in the filaments 3!, and the pipe and jet assume the inoperative position shown in dotted lines.

In Fig. '7 a jet of the form illustrated in Figs. 1-9. is shown in use with a cylindrical collector device ,8 surrounding the whole of the jet, so that the air passing up the cell in counter-current to the filaments is constrained by the device 48 and a supporting diaphragm 49 to pass through the vicinity of the jet before reaching the drawoff pipe. 58 by means of which it is removed from the cell. The collector 48 also constrains the additional air to flow in intimate contact with the filaments. Further additional air may be introduced into the cell by means of perforated ring 53.

Fig. 8 shows a similar collector device 48 used in conjunction with a plain jet 5!, additional air being supplied by a pipe 52 and perforated ring 53 which entirely surrounds the filaments. The position of the orifices 54 in the ring 53 is such that the air is directed upwards and inwards, so that the air flows through the collector 48 in close contact with the filaments.

Fig. 9 shows a collector device 56 depending from the filter 30 and surrounding the jet. An air supply pipe 5'! and perforated ring 58 supply a downward current of air from just above the jet, the said current passing down the collector 56 in intimate contact with the filaments before joining the counter-current of air which is proceeding to the draw-off pipe 50.

Any of the devices introducing additional medium inside the bundle of filaments, as illustrated in Figs. 1-? may be used in conjunction with devices for supplying additional medium outside the filaments, such an arrangement being shown in Fig. '7, in which a perforated ring 53 is shown for supplying air to the outside of the bundle of filaments 3| in addition to the air supplied inside the bundle.

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

ments, and introducing. additional evaporative medium inside the bundle of filaments from behind the point of extrusion. V

2. Process for the production of artificial filaments from solutions of cellulose derivatives by .the evaporative method, comprising extruding a rative medium in the vicinity of the point of extrusion, both inside and outside of the bundle of filaments. V

3. Dry-spinning apparatus for the production of artificial filaments, comprising a spinning V chamber, a spinning jet adapted to extrude a bundle of filaments into said chamber, means adapted to draw an evaporative medium through said chamber in counter-current to the direction of extrusion of the bundle of filaments from the jet, and means for introducing additional evaporative medium in the vicinity of the jet, both inside and outside the bundle of filaments.

4. Dry-spinning apparatus for the production of artificial filaments, comprising a spinning chamber, a spinning jet adapted to'extrude a bundle of filaments into said chamber, means adapted'to draw an evaporative medium through said chamber in counter-current to the direction of extrusion of the bundle of'filaments from the o jet means for introducing additional evaporative medium both inside and outside the bundle of filaments in, the vicinity of the jet, and means adapted to constrain the additional evaporative medium to maintain intimate contact with the filaments.

EDWARD KINSELLA.

JOSHUA BOWER.

ROBERT PIERCE ROBERTS.

JOHN FREDERICK BRIGGS.

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