US2742667A - Spinnerets - Google Patents

Description

SPINNERETS Filed Feb. 29, 1952 yam '3 II. 'L'IIIIIIIIIIIIIIIIIJY/l IAZI'/IIIIIIIIIIAV/ United States Pa ent 2,742,667 SPINNERETS Claude Clouzeau and Jean Etienne, Lyons, France, assignors to Societe Rhodiaceta, Paris, France, a company of France Application February 29, 1952, Serial N 0. 274,266 Claims priority, application France November 8, 1951 1 Claim. (Cl. 18-8) This invention relates to thick metallic spinnerets i. e. of a thickness greater than 1.5 mm., intended for the manufacture of all artificial or synthetic filaments, threads, horse-hair and the like.

A spinneret according to the invention is characterised in that each of the orifices in the spinneret comprises a. cylindrical part extending from the out-side face of the spinneret and a coaxial inverted truncated conical part whose large base is situated in the inside face of the spinneret, the height of the cylindrical part being less than 7 of the thickness of the spinneret, and the truncated conical part having an angle between the sides within the range of 15 to 60. The cylindrical part can be either directly connected to the conical part or indirectly through an intermediate part formed by a figure of coaxial revolution, for example, a truncated cone whose height is less than 7 of the total thickness of the spinneret which can be as much as, or greater than, mm.

The orifices of the spinnerets according to the invention are of a form which is particularly suited to obtaining a highly polished, practically glazed, surface condition over the whole extent of their walls. However, these walls can be given any other desired characteristic and in particular they can comprise, hollowed or in relief, any figure or any design.

The spinnerets according to this invention are easier to start spinning with than the spinnerets previously known, they are favourable to very steady spinning of the materialbeing spun, and can be used longer whilst continuing to give products of excellent quality. They are, moreover, very simple to clean with the agents generally used.

The spinnerets according to the invention can be in the form of discs or of cups and comprise any number of orifices. They can be made of any metal, for example, nickel, or chromium steel containing practically no nickel, but preferably they are made from a steel containing chromium and nickel, for example 18% chromium and 8% nickel. Such steel has excellent resistance, both to the abrasion produced in the course of spinning and to chemical attack occasioned either by the products spun or by the acids, for example, concentrated hot nitric or sulphuric acid, generally used for cleaning spinnerets. In particular, this resistance is better than that of chromium steel containing no nickel or very little. Also, steel containing chromium, possibly nickel, and in addition one or more other ingredients normally employed in the composition of steels called special such as for example, manganese, titanium, molybdenum, vanadium, copper or tungsten, may be used for the manufacture of these spinnerets.

The spinnerets forming the subject of the present invention can be utilised for the manufacture of all filaments, threads, horse-hairs etc. whether artificial or synthetic, particularly for those having a base of: cellulose esters (especially cellulose acetate), polyvinyl derivatives (especially polyvinylchloride, vinylchloride-vinyl acetate copolymer, polyvinylcyanide), superpolycondensates (especially superpolyamides, superpolyurethanes and superpolyesters).

" They are equally well suited for the dry or wet spinning of products in solution or suspension and for spinning products in their melted state.

The invention is illustrated in the accompanying drawings, whereinz' Fig, 1 shows one orifice to an enlarged'scale;

Fig. 1A is a sectional view of a spinneret with a multiplicity of orifices according to Fig. 1;

Fig. 1B is a plan view of Fig. 1A;

Fig. 2 shows a second form of one orifice.

Fig. 2A is a sectional view of a spinneret with a multiplicity of orifices according to Fig. 2; and

Fig. 2B is a plan view of Fig. 2A.

The following examples, which are not limitative, are given so as to make the invention more easily understood.

Example 1.32 orifices (one of which is shown in Fig. 1) spaced at regular intervals over a circumference of 30 mm. of diameter are pierced in a cup-shaped piece 1 of rustless steel containing 18% chromium and 8% nickel, of 2 mm. thickness. The piercing is done in such a way that each of these orifices has the form represented in Fig. 1, i. c. it is composed of a cylindrical part2 united directly to a coaxial truncated conical part 3 intended for reception of the product to be spun.

The cylindrical part 2 having a diameter of 0.08 is 0.06 mm. in height.

The angle between the sides of the truncated conical part 3 is 35 These spinnerets are particularly well suited to spinning a solution of cellulose acetate in acetone.

Example 2.-l8 orifices (one of which is shown in Fig. 2) spaced at regular intervals over a circumference of 32 mm. diameter are pierced in a disc 1* of special steel containing 21% chromium, 7% nickel and 0.4% titanium, of 6 mm. thickness. This piercing is done in such a way that each of these orifices has the form shown in Fig. 2, i. c. it comprises a cylindrical part 2 joined through the intermediary of a coaxial truncated conical part 4 to a truncated conical part 3 having the same axis, intended for the reception of the product to be spun.

The cylindrical part 2 of a diameter of 0.18 mm. is 0.15 mm. in height.

The truncated conical part 3 whose entry base diameter is 3.3 mm. has an angle between the sides of 25. The truncated conical part 4 joining the cylindrical part 2 to the truncated conical part 3- is 0.40 mm. in height.

' These spinnerets are particularly well suited to spinning melted superpolyamides.

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

A spinneret of the character described comprising a disk having flat and unobstructed inner and outer surfaces disposed parallel to each other, the said disk being of a uniform thickness throughout its area greater than 1.5 mm. and beingbored with a multiplicity of orifices extending entirely throughthe said disk and spaced' from each other, the said orifices being of duplicate formation and each consisting of a short cylindrical outer end portion of small diameter leading from the outer surfaceof the disk and the height of which is less than A of the thickness of the disk, 21 main portion of inverted truncated conical formation extending downwardly from the said inner surface in concentric relation to the said cylindrical outer end portion for more than of the thickness of the said disk and at its lower end being of appreciably greater diameter than the diameter of the cylindrical outer end portion, the angle between the sides of said main portion being between about 15 and 60 and the length of said main portion being greater than its largest diameter, and another inverted conical portion connecting said main portion with the inner end of the cylindrical portion the length of which is greater than that of 3 the said cylindrical portion, but less than 5 of the 2,266,363 thickness of the said disk, the smallest diameter of which 2,341,555 is equal to that of the said cylindrical portion, and the largest diameter of which is equal to the smallest diam- 878 935 eter of said main portion. 5

References Cited in the file of this patent UNITED STATES PATENTS Dreyfus May 6, 1924 10 Graves Dec. 16, 1941 Jones Feb. 15, 1944 FOREIGN PATENTS France Nov. 2, 1942

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