US2703433A

US2703433A - Spinneret for the manufacture of staple fiber filaments

Info

Publication number: US2703433A
Application number: US131331A
Authority: US
Inventors: Holzmann Hermann
Original assignee: Degussa GmbH
Current assignee: Evonik Operations GmbH
Priority date: 1948-12-03
Filing date: 1949-12-06
Publication date: 1955-03-08
Anticipated expiration: 1972-03-08
Also published as: FR1007347A; CH270511A; DE809230C

Description

March 8, 1955 HQLZMANN 2,703,433

. SPINNEREET FOR THE MANUFACTURE OF STAPLEFIBER FILAMENTS 2 Sheets-Sheet 1 Filed Dec. 6. 1949 March 8, 1955 H. HOLZMANN 2,703,433

SPINNERET FOR THE MANUFACTURE OF STAPLE FIBER FILAMENTS Filed Dec. 6, 1949 2. Sheets-Sheet 2 -oooooo OOO QOOOO OOO //YVEA' rag 41- TOPIYEYS United States Patent SPINNERET FOR THE MANUFACTURE OF STAPLE FIBER FILAMENTS t Hermann Holzmann, Hanan on the Main, Germany, as-

lignor to Deutsche Goldund Silber-Scheideanstalt vormals Roessler, Frankfurt am Main, Germany, a cor poratlon of Germany Application December 6, 1949, Serial No. 131,331 In Germany December 3, 1948,

Public Law 619, August 23, 1954 Patent expires December 3, 1968 Claims. (c1. 18-8) This invention relates to spinnerets for the manufacture of staple fibre filaments, especially in the viscose process and pertains more particularly to an improvedspinneret bottom with annular channels without spinning openings. The object of this invention is to provide a spinneret whereby at least one annular channel without spinning holes is arranged in addition to the radial hole-tree channels.

A further ob ect is to provide a spinneret with concentric annular channels whereby the intervals between the annular'channels increase towards the center of the spinneret bottom. Other objects of my invention will be apparent as the detailed description of my invention proceeds.

The main disadvantage attendant upon the use of multi-perforated spinnerets for the manufacture of staple fibre filaments, especially according to the viscose process, was the ditficulty in directing the precipitant bath fluid through the thick bundle of filaments to the holes at the center of the spinneret bottom. Furthermore, the precipitant bath becomes already partly neutralized or diluted inside the bundle of filaments and is therefore devoid of the same coagulating efiect in the surrounding of the spinneret axis.

As it is known, this difliculty was soon overcome by arranging the openings in the spinneret bottom with interspaced channels for an easier inflow of the precipitant bath fluid towards the center of the spinneret instead of squally distributing the spinning holes over the whole spinneret bottom. Even in varying the shape and size of the channels, the latter are always arranged in radial direction.

I have discovered that the spinning capacity of multiperforated spinnerets may be most favorably influenced, if, for instance, concentrically arranged annular channels are provided in addition to the radial channels. My invention relates therefore to a spinneret for the production of staple fibre filaments according to the viscose process, with radial hole recesses at the spinneret bottom whereby at least one annular channel exempt from openings is arranged in addition to the radial channels without spinning holes. These concentric annular channels connect the radial channels with each other, thereby causing a further guiding of the precipitant bath inflow which intensifies the distribution of the filament bundle.

Furthermore, this device also counteracts a too extensive deviation of the precipitant bath fluid in the direction of the filament bundle center. According to my invention the division of the spinneret bottom into radial and concentric recesses makes possible narrowing the intervals between the spinning holes in their respective bottom partitions to a higher degree than it was hitherto known. In my new spinneret the effect which is exerted by the particular subdivision of the spinneret bottom may be still further enhanced by arranging the concentric annular channel recesses containing the spinning openings in growing intervals, beginning at the periphery and i. e. the two outer annular channels have the same width, whilst the centripetally ad usted third and fourth channels are narrower and so fort l have turther round trom experiments that spinnerets containing the new annular cnannels in addition to radial channels yield an excellent unnorm quanty ot' filament. 'lhese spinnerets are alSO more IeSlSKaDC against wearing away one to continued usage and superior to spinnerets with radial channels only. Moreover, the spinnerets according to my nvention may contain a suprismgly large number of spinning holes in spite of recesses, due to the diminished intervals between the spinning holes without deteriorating the quality of the tnamenr. 'lhus it is possible to obtain especially ravorable conditions for the manufacture or staple nore whilst observing the most economical use of the precious spinneret material. The new spinneret is thererore a distinct improvement in the production of rayon, especially staple hbre filaments.

l have illustrated a preferred form of my device in the accompanying drawings. Fig. l discloses the spinneret bottom in a plan view of the device. Fig. 2 discloses a segment of rig. 1 in a larger scale.

in Fig. 1 l have shown tour concentrically arranged annular channels exempt from holes (bi, b2, bz, hr) in addition to the usual radial channels without spinning holes, as indicated in Fig. 2, the intervals between the annular channels b1, b2, b3 and b4 (namely, the width of 02, 0a and 04) increase from the periphery to the center of the spinneret plate bottom. Each pair of the annular channels has the same width. Thus, the width of the annular channels b1 and 11: corresponds to space d, whilst the width of the annular channels ha and b4. is in accordance with the narrower space e. The series of the spinning holes are broader at the center of the spinneret bottom. Therefore the outermost row of holes shows the smallest width (or), the innermost row of holes the greatest width (03).

The channels may be carried out either in the form of planes without openings or in the form of grooves or notchings.. It is even possible to notch only one kind of the channels, i. e. either the radial or the annular channel whereby the grooved channels may die out into the plane ones.

What I claim is:

l. A spinneret for the production of staple fibre filaments having a plate provided with a plurality of spinning openings arranged about a center in groups spaced from each other to provide concentric annular opening free channels in said plate and to provide radial opening free channels in said plate extending towards said center between said groups of openings, said radial channels communicating with said concentric annular channels, the spacing between the groups of spinning openleading to the center of the plate. A further advantage ings providing the radial and annular opening-free channels being substantially greater than the spacing between the individual spinning openings in each group, and the openings in eachgroup being arranged in a plurality of rows disposed at different distances from said center.

2. A spinneret for the production of staple fibre filaments having a plate provided with a plurality of spinning openings arranged about a center in arcuate groups spaced from each other to provide concentric annular opening free channels in said plate and to provide radial opening free channels in said plate extending toward said center between said arcuate groups of openings, said radial channels communicating with said concentric annular channels, the spacing between the groups of spinning openings providing the radial and annular opening-free channels being substantially greater than the spacing between the individual spinning openings in each group, and the openings in each group being arranged in a plurality of rows disposed at difierent distances from said center.

3. A spinneret for the production of staple fibre filaments having a plate provided with a plurality of spinning openings arranged about a center in arcuate groups spaced from each other to provide concentric annular opening free channels in said plate and to provide radial opening free channels in said plate extending toward said center between said arcuate groups of openings, said radial channels communicating with said concentric annular channels, the spacing between the groups of spinning openings providing the radial and annular openingfree channels being substantially greater than the spacing between the individual spinning openings in each group, the openings in such groups being arranged in a plurality of rows disposed at different distances from said center have a greater width in the radial direction than arcuate groups further out from the center.

4. A spinneret in accordance with claim 3, in which the width of the annular opening free channels near the center is less than the width of the annular channels further out from said center.

5. A spinneret for the production of staple fibre filaments having a plate provided with a plurality of spinning openings arranged about a center in arcuate groups spaced from each other to provide concentric annular openingfi'ee channels in said plate and to provide radial opening free channels in said plate extending toward said center between said arcuate groups of openings, said radial channels communicating with said concentric annular channels, the spacing between the groups of apinning openings providing the radial and annular opentug-free channels being substantially greater than the spacing between the individual spinning openings in each group, the openings in such groups being arranged in a plurality of rows'disposed at itferent distances from said center and in which the width of the annular opening free channels near the center is less than the width of the annular channels further out from the center.

' References Cited in the tile of this patent FOREIGN PATENTS 321,344 Germany May 3t, 1920 395,524 Germany May 22, 1924 286,342 Great Britain Feb. 20, 1928 647,913 France Aug. 6, 1928 809,230 Germany July 26, 1951