US2548357A

US2548357A - Manufacture of textile fibers composed of casein

Info

Publication number: US2548357A
Application number: US714130A
Authority: US
Inventors: Ferretti Antonio
Original assignee: Individual
Current assignee: Individual
Priority date: 1941-03-06
Filing date: 1946-12-05
Publication date: 1951-04-10
Anticipated expiration: 1968-04-10
Also published as: NL66502C; GB615305A; FR921563A; DE909491C; CH229823A; BE443631A

Description

Patented Apr. 10, 195i t COMPOSED or CASEIN Antonio- Ferretti, Milan-Italy N0 niawiii'g; Application December Se rialNoI 714,130; Inltaly Mirch'G, 1941' Section 1, PublicLaw sec, AiiEiist 'B, 1946- Patent expires Marc1i*-6, 1 96-I- 1; This invention relates to the manufacture of textile fibres composed of casein or" partly of casein and partly of cellulose u It is known to treat azr'tificial fibres composed of cellulose (rayon) first with'a solution of urea and then, after thefib'r has" absorbed a sum- Ciiit dlialit itvo f urea; with formaldefii'ael s0 astofoiiii on the fibre an inl soluble l roduct'of' co'ndens'ati'oii' which parti'allj Waterproofs the fibf'andrehdis it morefh ighly resistant the effects of moisture} and atthe saffx'ie 'tiiiieto'obtairi a" fib'rewhich is crjeaseles'sl' Attempts'li'ave been madealso to" treat casein fibresifithe Sarfi way; that is first witli'ui'ea and then Withformaldehyde". Ithas'been'found', however; that Slic'h' treatment fa'ilsto' p'io'dube anyappreciableefiect on the casein'fibrei' This" is diie t'o'fthe fact that a casein fibre, that is, as

ordinarily ro'duced, with the use of formame hyde in the insolubilising treatment; contains for-f ni'aldehyde and for the reason is preventedfrom' absorbing the necessary quantityo'f urea; which instead of cominginto*co'ntact with-theform-' aldehydealre'a'dy present'in 'the fibres condenses on the exterior surface thereof and thereforms a' 'pulverulent deposit of condensed "urea "effective to prevent the passage" of urea into'the' interior of the. fibrei V It is further known that; casein dissolves" in aqueous solutions" of] urea and it is known also to use a"solution'of casein in anaqueous'solu tion of urea as thespinningsolution in themanu;

facture 10f wet-spun fibres, that is, fibres-prof dupedby spinninga" solution of the basic substance of which the fib're is to 'be'composed in a coagulation bath operative to coagulate the thin stream ofsolutio'n entering the bath into a filament. Successful results are, however, not

obtainableby' this process: it 'isdifficult to obtainperfect coagulation. In addition,"a spongy load tends to' form inside the fibli' durfingthestep of insolubilisingthe fibre with form aldehyde, This is due to the morerapid rea tion of the formaldehyde with the 'urea" con tained in-the fibre than witnthetasenr of; which the fibresis composed, the' urea; fibre hardening in consequence 'before the 'casiein substance of the fibre and forming in "the resultan amorphous orspong'y load insidefthe' 'fib-re. Owing to thepresence of v thisfload in the fibre,

. the latter is'less resis'tanttodryness and'inoisture, According to the present"invention; a"processf composed of casein or partly or casein and pafift of? cellulose; comprisesspinning a solutionfmore especially an aque'oussqlutiong; of. casein or ..of

a; mixture .of' casein," and. cel1ulosic viscosein a:

formaldehyde-free, poagulation: bath, and .treat ing the1 coagulated-: filament; in a succession ,pfi baths including ,or comprising, inmthe, order.

named; (a) a bath-or baths consisting-10f urea dissolved. in a" solution, morev especially: an .aque-,. ous solution, of a neutral or acid salt of, azmineljal. or organic acid and; (b); ..a. urea wires saline bath or: baths containing formaldehyde; more especiallyianiaqueous;batlror-bathsof thisdescriptiom; It; is" tobe} understood that the successiomof;

baths through which:the coagulated, iilament is passed-i1! :Qrfder to producefi i hedfibre may ciudezother baths.- additional to ,the baths- (a); and: Kb) mentioned above. for. example: deacidiflying and partially, hardening baths, as ingthe,

specific examples-of the invention hereinafter set forth.

The: baths or baths (dif or are and possessed of, an astringent action towards the"filament;Itorithey may I01, example, be

of a;.comDosition; -similar;touthe baths h t are. used in the processes forming the subjectmatter of U. S. patent applications .dated August .17,

April "4; 1939., SeraNoL 270,9 19, ,noyv .abandqngg i b u y 17, 19 .8,. senwNot v 30.12 1.J W ab ndoned;,Ju1y-:3 11940, fier- .N.o.. e18. 9 ..:no a n cloned; and U. S. Patents No. 2,338,915; No. 2,297,397; No. 2,338,911,;

It is found that case fibres and mixed casein and. cellulose f'fibre's produced'in accordance with thj present'finven iras outlinedabove are'cona sidjerably'improve as compared with casein fibres andmifieii casein: cellulose fibres" as" ordi-' narily' prdducedf inf fres'pect of-resistanceitq mois= I ture, resistance td 'thej boiling acid bathsthat are used for dyeing andresistance to soap"and" water in the inaphine of fast "colors.

F t i ibiwm t zfr s est' o t dl r. going propertiesfantl a higheriorder of st'rength" with rynes and; moisture *o ffthe fibre are ob' .e, jr safeea a nuo i thiea i t rs'mslfi least th a or baths containing iorma'ldehyd'orafter *the" fila' it is out, it being: convenient to itreat in this manner a large number o'f filaments simultane ou'sly spunfin the coagulating? bath ria-- then l j' t e l' h quent" (post-coagulatio proc ss ionni ath s b, H a plicationsfd'ated FbrUa'iyTY, 1938; SGT.

'aW'n' out and en-i" i es ates- 330,725 now abandoned; July 31, 1940, Ser. No. 348,992 now abandoned; and U. S. Patent No. 2,338,917.

In order to obtain a higher resistance of the fibres that are produced in accordance with this invention to acid boiling than is obtainable with the use of normal temperature in the baths (a) and (b) a temperature above 28 C. may be employed in those baths or at least in the bath or one or more of the baths (1)) containing formaldehyde, as in the process forming the subject matter of the aforesaid U. S. patent applications No. 330,725, 348,992, both now abandoned and U. S. Patent No. 2,338,917, for example, if a temperature not above 25 C. has been used in the bath or baths (a) and also in one or more of the insolubilising, formaldehyde containing baths (1)), a temperature above 25 C., preferably a temperature of 70-75 C., may be employed in another or other of the baths (2)) subsequent in the succession of baths to the first-mentioned of the baths (b). In this way, the fibre obtained will be much softer and larger after acid boiling than a urea-free fibre and from. this point of view, can be compared with a fibre treated with a chromium salt, but with the advantage, however, that the fibre retain a perfectly white appearance.

It should be remarked that casein filaments alreadycoagulated but not yet insolubilized by formaldehyde, cannot be treated with a simple solution of urea, as a simple solution of urea dissolves casein and in consequence the filament would at once dissolve in the solution. On the other hand, by using a saline solution of urea; preferably concentrated and astringent, no dissolving of the filament occurs, but only a slight swelling of the filament, which can be adjusted at will by varyin the degree of concentration and/or the astringent capacity of the solution according to the amount of urea that has to be absorbed by the filament and to the degree of penetration of the urea that has to be obtained.

Urea may in some cases be present in the formaldehyde-free acid salt coagulating bath, but in general, coagulation of the filament is hindered and there tends to be a large loss of urea in the first de-acidifying bath following the coagulating bath.

Examples '1.- 100 kgs. of washed and dried casein are swelled in water and then dissolved in an aqueous solution of caustic alkali, equivalent, for instance, to 20 litres of sodium hydrate at 5 B. The volume of the resulting solution of casein is then increased to 500 liters, after which the solution is filtered one or more times. After maturation it is spun in theform of filaments in a formaldehyde-free coagulating bath containing, for instance, 90 gms. of 66 Baum sulphuricacid and 350 grs. of sodium sulphate per litre of the bath. The filaments emerging from the coagulating bath are gathered together in a continuous ribbon and passed on, preferably under more or less tension through the following baths in succession:

(a) An aqueous saline bath containing 200 gms. of sodium. chloride per litre.

(b) An aqueous saline bath containing 150 gms. of sodium chloride, 200 gms. of aluminium sulphate and 150 gms. of alumina paste containing of A1203 per litre.

(0) An aqueous saline bath having the composition of the bath (1)) but containing in addition gms. of urea crystals per litre of the bath and more sodium chloride until the bath is saturated.

(d) An aqueous saline bath having the composition of the bath (b) but containing in addition 39-40 gms. of 100% formaldehyde per litre of the bath.

The fibres are now out to the required length after which they are treated, preferably in an autoclave, in an aqueous bath (e) containing gms. of aluminium sulphate, 200 gms. of sodium chloride and 40 gms. of 100% formaldehyde per litre, for 5-6 hours.

The insolubilized fibres are now washed and treated in an aqueous bath or baths (1) of soluble phosphates, for instance such a bath containing 4 gms. of monosodium phosphate per litre, after which the fibres are washed again and dried.

The preferred temperature for the various baths are: 35 l0 C. for bath (a) 50-55 C. for bath (b):

35-40 C. for bath (0):

50-55 C. for bath (d):

70-75 C. for bath (e):

35- l0 C. for bath or baths (7):

II. The procedure in this example is the same as in Example I, except that the filaments are out after bath (0) instead of after bath ((1), the out fibres being gathered together in a vessel containing bath ((1), in which they are treated for 3-4 hours at 35-40 C., then treated in bath (e) at 70-75 C. for 5-7 hours, then washed, then treated in the bath or baths (1) and finally, washed again and dried.

III. The procedure in this example is the same again as in Example I, except that the filaments are out after the bath (b) instead of after bath (d), the cut filaments being gathered together in a vessel containing bath (0) in which they are treated for 2-3 hours at 35-40 C., and then, after having been squeezed out, in conformity with Example II, omitting bath (e).

IV. The procedure in this example is the same again as in Example I, except that the aluminium sulphate in bath (e) is replaced with more sodium chloride until the bath is saturated.

V. The procedure in this example is the same as in Example I to IV with the use of the baths (a), (b), (c), (d), and (e) as specified therein, with the exception that the aluminium sulphate and/or sodium chloride are either partly or totally substituted in the baths with other soluble neutral or acid salts including, for example, sulphates, chlorides, formiates, acetates, lectates or nitrates, of the mineral or organic acids.

It is to be understood that the term urea as employed herein includes all soluble salts containing urea such for example as thio-urea.

It is also to be understood that the invention includes both the use of milkcasein and also the use of vegetable casein for example soya bean casein, either being used alone or the two in admixture with one another.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is performed, I declare that what I claim is:

1. Process for manufacturing casein textile fibers comprising the wet spinning of the casein solution into a coagulating bath free of formaldehyde to form casein filaments; and, after removal from said bath, treating such filaments in at least one bath containing a substantial con- .centration ofurea, but being free of "formaldee hyde, "whereby uncondensed urea penetrates the filaments and is absorbed therein, said urea bath containing at least one non-basic soluble salt rendering the bath substantially saline and thereby functioning to a degree sufiicient for the protection of the filaments against dissolving into such bath; and thereafter removing such urea-containing filaments from said urea bath and treating the same in at least one urea-free formaldehyde bath of saline character for insolubilizing the same.

2. Process as in claim 1 and wherein the urea bath is rendered saline by incorporating therein to the saturation point non-basic soluble salt material.

3. The process as in claim 1 and wherein the urea bath is maintained at temperatures elevated above 25 C.

4. The process as in claim 1 and wherein the urea bath is maintained at an elevated temperature of about 35 to 40.

5. Process as in claim 1 and wherein the coagulated filaments are kept under stretching tension during passage through the coagulating and urea and formaldehyde baths until the time when the hardened fibers are cut to length.

6. Process as in claim 1 and wherein the coagulated filaments are kept under stretching tension during passage through the saline washing bath and the saline bath containing sodium chloride and an aluminum salt and the saline bath containing urea and the saline bath containing formaldehyde.

7. Process as in claim 1 and wherein the aqueous urea bath is rendered saline by the addition of sodium chloride and an aluminum salt.

8. Process as in claim 7 and wherein the aluminum salt is aluminum sulphate.

9. Process as in claim 1 and wherein the aqueous urea bath is rendered saline by the addition of sodium chloride and aluminum sulphate.

16. Process as in claim 1 and wherein the aqueous urea bath is rendered saline by the addition of sodium chloride and aluminum sulphate in the proportions, per liter, of about grams of urea crystals, about grams initially of sodium chloride, and about200 grams of aluminum sulphate; the sodium chloride content bein then increased unti]. substantial saturation is reached.

11. Process as in claim 10 and wherein the aqueous urea bath is added about 50 grams of aluminum paste containing about 10 percent of aluminum oxide.

ANTONIO FERRETTI.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date Meigs Aug. 20, 1940 deKadt Mar. 2, 1943 FOREIGN PATENTS OTHER REFERENCES Ser. No. 327,734, diVascO (A. P. C.), published Apr. 27, 1943.

Number Number

Claims

1. PROCESS FOR MANUFACTURING CASEIN TEXTILE FIBERS COMPRISING THE WET SPINNING OF THE CASEIN SOLUTION INTO A COAGULATING BATH FREE OF FORMALDEHYDE TO FORM CASEIN FILAMENTS; AND, AFTER REMOVAL FROM SAID BATH, TREATING SUCH FILAMENTS IN AT LEAST ONE BATH CONTAINING A SUBSTANTIAL CONCENTRATION OF UREA, BUT BEING FREE OF FORMALDEHYDE, WHEREBY UNCONDENSED UREA PENETRATES THE FILAMENTS AND IS ABSORBED THEREIN, SAID UREA BATH CONTAINING AT LEAST ONE NON-BASIC SOLUBLE SALT RENDERING THE BATH SUBSTANTIALLY SALINE AND THEREBY FUNCTIONING TO A DEGREE SUFFICIENT FOR THE PROTECTION OF THE FILAMENTS AGAINST DISSOLVING INTO SUCH BATH; AND THEREAFTER REMOVING SUCH UREA-CONTAINING FILAMENTS FROM SAID UREA BATH AND TREATING THE SAME IN AT LEAST ONE UREA-FREE CORMALDEHYDE BATH OF SALINE CHARACTER FOR INSOLUBILIZING THE SAME.