US2141776A

US2141776A - Cellulosic structure and method for preparing same

Info

Publication number: US2141776A
Application number: US748880A
Authority: US
Inventors: Vautier Leon Pierre Georges; Fays Rene Edouard
Original assignee: EI Du Pont de Nemours and Co
Current assignee: EIDP Inc
Priority date: 1933-11-03
Filing date: 1934-10-18
Publication date: 1938-12-27
Anticipated expiration: 1955-12-27

Description

C- 7, 1933- L. P. G. VAUTIER E'l AL ,776

CELLULOSIC STRUCTURE AND METHOD FOR PREPARING SAME Filed Oct. 18, 1934 2 Sheets-Sheet l L m m;

I ulu I $1" l 14 3 IIIIIIII E l8 INVENTOR5. F 3 Leon PL'errc Georges VdutLcr' 1G1 Rene Edouard Hays ATTORNE Dec. 27, 1938. P. G. VAUTIER E1. AL

GELLULOSIG STRUCTURE AND METHOD FOR PREPARING SAME 'vmv- W 7 will IIIIIIIIIII sq v C B INVENTORS.

Leon Pierrc Georges Vaufier FIG- Rene Edouard H1 ATTO R NET.

UNETED STATES PATENT OFFIE CELLULOSIC STRUCTURE AND METHOD FOR PREPARING SAlVIE Leon Pierre Georges Vautier,

Saint-Justdes- Application October 18, 1934, Serial No. 748,880 In France November 3, 1933 10 Claims.

This invention relates to the continuous production of non-fibrous cellulosic sheet material. More particularly, it relates to the production of such materials having new and pleasing optical efiects. The invention will be described in terms of seamless cellulose tubes regenerated from viscose although it is to be understood that it is equally applicable to non-fibrous sheet material generally and in practicular to non-fibrous cellulosic sheet materials in the form of tubes, strips and the like.

Recently seamless tubes of regenerated cellulose have come into extensive use as ornamental and decorative ribbons or strips for the manufacture of millinery and other purposes. Similar tubes of larger diameter have been in use as substitutes for animal casings on sausages. They have also been used as decorative and protective sleeves over various articles of manufacture, upon which they may be applied in a gel state and allowed to stand, whereupon they shrink down tightly over the articles as a result of the evaporation of their contained water.

It has been customary to impart various pleasing, ornamental efiects to tubing of the type above mentioned, such as by incorporating various materials in the viscose from which the tubes are cast. and a tube so produced presents a homogeneous appearance which has been found suitable for many uses.

Heretofore, in the manufacture of these tubes 21 viscose solution has been introduced through an annular extrusion device into a coagulating bath, followed by suitable purification steps and, if desired, printing or other subsequent fashioning. The extrusion devices for cellulosic tubing used up to the present are only adapted to the use of a single-colored coagulable solution so that the finished tube must be of a single homogeneous optical appearance, such as entirely opaque or entirely metallic or entirely transparent, or a mixed coagulable solution may be used to produce a product having a mottled appearance.

An object of this invention is to continuously produce tubes of regenerated cellulose or other non-fibrous sheet materials exhibiting novel and pleasing color effects. Another object of the invention is the provision of an extrusion device useful in the manufacture of such novel tubes. A still further object is to produce seamless tubes exhibiting the aforesaid color effects. A still further object is the production of striped tubes in which the boundary lines between adjacent stripes are sharply defined. Still another object of this invention is the production of tubes having firmly united concentric layers of non-fibrous cellulosic materials.

The objects of this invention are accomplished in general by extruding viscose or other liquid from which non-fibrous sheet material may be coagulated through a novel extrusion device into a coagulating bath. This extrusion device consists of two or more chambers for introducing coagulable solutions capable of producing pellicles of different optical characteristics, for passing the solutions in parallel relationship, sep arated by dividing walls, towards an extrusion orifice, and for subsequently uniting the two coagulable solutions just prior to their extrusion into a coagulating bath. This device is adapted to produce a tube having parallel stripes or concentric layers which are sharply defined from one another, exhibiting a pleasing decorative efiect and increased strength.

The solutions capable of producing pellicles of diiferent optical characteristics may be differently colored or some of them may be colored, whereas others are transparent, or some of them may contain metallic particles, etc. It will be understood that a pellicle of different optical characteristics may be formed from a variety of solutions. For simplicity, reference will be made hereinafter to differently colored solutions.

It will be further understood that the cellulosic solutions will in all cases be sufliciently similar so that they will merge or unite to produce a unitary structure.

The details of the invention and the advantages thereof will become more clearly apparent by reference to the following description taken in connection with the accompanying illustrations of one specific embodiment thereof, and in which:

Fig. 1 is a vertical sectional view of an extrusion die for forming cellulosic tubing;

Fig. 2 is a sectional view taken along the line 22 of Fig. 1;

Fig. 3 is a perspective view of a tube, such as may be formed by the die shown in Figs. 1 and 2;

Fig. 4 is a vertical sectional view of a modified form of extrusion die for forming cellulose tub- Fig. 5 is a sectional view taken along the line 55 of Fig. 4;

Fig. 6 is a perspective view of a tube, such as may be formed by the die shown in Figs. 4 and 5.

Inasmuch as innumerable modifications of this invention are possible, the detailed description and the accompanying illustrations will be confined to a method and apparatus for the production of striped tubing and tubing composed of oncentric layers of differently colored sections, r having opaque and transparent sections. Obiously, this invention may be employed for the roduction of any system of stripes such as, for xample, stripes numbering from two to a dozen r more, or the stripes may be of diiferent widths r they may be all of the same width.

Referring in detail to the drawings, reference haracter l designates the outer shell or housing f an extrusion die for forming cellulosic tubing. .he die shell H has a hollow extension l2 which erminates in an orifice I3. A die insert or plug 4 is positioned within the die shell II and is Jaintained in spaced relationship therewith by ooperating surfaces of the insert l4 and shell I I. .hese surfaces are held in engagement with each ther by means of end plate l5 and bolts Hi. The asert I4 is provided with a cylindrical extension I which projects into the hollow portion of the xtension l2 and is substantially concentric herewith to provide an annular hollow chamber 8 between the internal surface of the extension '2 and the'external surface of the cylindrical exension IT. The insert I4 is provided with a lurality of partitioning ribs l 9 which project into he annular chamber [8 so as to divide the same ato separate

arcuate chambers

20, 2i, 22, and 23. Zach of these arcuate chambers terminates at one nd in the common orifice l3 and at the other nd they are conneced to individual supply pasages, each of which is provided with its own upply of cellulosic solution. The chambers 20,

l

22 and 23 are supplied. with cellulosic solutions y means of

conduits

24, 25, 26 and 2! respecively. A tubular member 28 is positioned within he insert or plug I l and is adapted to project herefrom so as to be located within the tubing hich is extruded from the orifice I3. The memer 28 may be concentrically spaced within the asert i l by means of a bushing 29 or the like. Eoagulating fluid is passed through the member 8 to the interior of the extruded tubing.

The ribs l9 terminate at the junction of the rcuate chambers 2U -23 with the orifice l3 so lat the various cellulosic solutions may flow toether and firmly unite to each other within the xtrusion nozzle slightly before the solutions are ontacted with a coagulating medium.

The striped tubing is produced by means of the bove mention-ed apparatus in the following maner:

Referring to the drawings, two or more differntly colored cellulosic solutions may be introuced by means of the

conduits

24, 25, 26 and 21 3 their respective chambers. The cellulosic soluions are passed from the respective chambers to he common outlet orifice I3 at which point they .ow together and unite just 'prior to coagulation f the same. The extruded tubing is passed into coagulating bath which is adapted to coagulate tie exterior thereof, whereas the interior surface f the tubing is coagulated by passing a cogulating liquid through the member 28. Fig. 3 lustrates a tube such as may be produced from he extrusion die shown in Figs. 1 and 2 when, or example, an opaque cellulosic solution is introuced to opposite channels and a transparent, ellulosic solution is introduced in alternate oposing slots. Reference character F designates .ie opaque portions of the tube and reference haracter E designates the transparent portions f the tube.

By reference to the drawings, it will be seen hat the viscose solutions contact each other only or a comparatively short distance before striking the coagulating bath. It will also be seen that the viscoses, at the point at which they meet, are flowing practically parallel to each other. These two features are necessary in order to be certain that the two viscoses do not appreciably intermingle before striking the coagulating bath. The ribs 19 are preferably beveled or rounded at the ends thereof which abut the orifice 13 to prevent the formation of eddy currents or variations in the pressure on the solutions, and thereby prevent blurring and waviness in the dividing line. If the distance from the coagulating bath to the point at which the two viscoses meet is greater than a certain maximum, there will likewise be intermingling and blurring. On the other hand, this distance should be sufiiciently great so that a firm and lasting bond is formed between the viscoses before they are coagulated.

The modified form of extrusion apparatus'illustrated in Figs. 4 and 5 comprises an outer shell or housing 35, terminating in an orifice 36. A die insert 31 is positioned within the die shell 35 and maintained in spaced relationship therewith in the manner set forth above in Fig. 1. The die insert 37 comprises a cylindrical extension 38 and an annular division ring 39. The division ring 39 is spaced from the cylindrical extension 38 so as to provide an annular channel 40. The annular channel 40 terminates at one end at the orifice 36. The other end of the channel is connected to supply conduits 4i and 42 by means of the annular groove 43 and the

openings

44 and 45 in the division ring. The division ring is also spaced from the internal surface of the housing 35 to provide a second annular channel 46 which terminates at one end in the annular groove and at the other end in the orifice 36. A plurality of radially extending partitioning ribs 41 are formed on the external surface of the division ring to divide the annular channel 46 into

arcuate channels

48, 49, 50 and 5!. These arcuate channels are individually supplied with cellu losic material by supply conduits 5!, 52, 53 and 54 respectively. The division ring 39 separates the

annular channels

40 and 46 up to a point closely adjacent the entrance to the orifice 36 at which point the two channels converge so that the solutions of cellulosic materials may flow together and securely unite before being coagulated. The

radial ribs 41 extend throughout the length of the channel 46 and across the groove 55. The ends of the ribs 4? and the division ring 39 are beveled or rounded to maintain a uniform pressure between the separated portions of the cellulosic materials which are flowing together and simultaneously entering the orifice. A tubular member 56 for supplying coagulating fluid to the internal portions of the extruded tubing is arranged within the cylindrical extension 38 in the manner set forth above with reference to Figs. 1 and 2. Fig. 6 illustrates a small section of tubing such as will be produced by the extrusion die of Figs. 4 and 5 when a substance for producing a transparent pellicle is passed through the inner channel 40 and the

arcuate channels

49 and 5|, which pellicles are designated in the tubing by A and B, and a solution for producing an opaqued pellicle is passed through the

arcuate channels

48 and 50, which pellicle is designated by C.

The modification of the extrusion die illustrated in Figs. 4 and 5 is obviously operated in the same manner as above defined with reference to the extrusion die illustrated in Figs. 1 and 2.

After issuing from the extrusion orifice, the material is led through the necessary coagulating and/or regenerating baths and thence through successive purifying baths and is finally wound up into reels and/or cut into short sections. The finished tubing shows parall-el stripes in which the dividing lines between stripes are extremely sharp and of pleasing appearance. Subsequently, the tubing may be printed with suitable indicia and/or submitted to other finishing operations.

In order to produce viscoses capable of yielding pellicles of optical characteristics different from those of colorless transparent pellicles formed from the ordinary viscose, it has been customary to add materials to the viscose before precipitation. These materials may be added to one or more of the viscoses used in the practice of this invention. Examples of materials which have been found suitable are pigments, particularly titanium oxide, to form opaque stripes; dyes, to form colored stripes; scintillating particles such as mica, to form stripes of metallic appearance; and others. Any desired combination of one or more of these materials may be added to any viscose, when it is desired to alter the optical characteristics of the film produced therefrom. For example, a pigment alone, a pigment and a dye, or any other combination may be used. In addition, the optical characteristics of a tube may be further altered in subse quent steps, for example, by dyeing after coagulation. These materials may be incorporated in the viscose, adding to the mixer water before the sodium cellulose xanthate is dispersed therein, or dispersing or dissolving in water and then adding to the viscose.

The following are examples of compositions and the products obtained thereby useful in the practice of this invention. In all the following examples, where percentages are mentioned, it is to be understood that the percentage is based on the weight of the cellulose in the viscose.

Example I .-Three portions of viscose are made up as follows:

To portion A is added 15% of titanium oxide and 1% of the red dyestuff known under the trade name Pontamine Fast Scarlet 4-BS (Color Index No. 326) to portion B is added 15% of titanium oxide and 0.5% of the blue dyestuff known under the trade name "Pontamine Sky Blue 5-BX (Color Index No. 520); to portion C is added 15% of titanium oxide. An extrustion device such as that illustrated by the drawings is used having a plurality of partitions forming twelve arcuate channels. Viscose from portions A, B and C is passed through alternate channels of the extrusion device. A tube is produced having a beautiful red, white and blue appearance, suitable as protective or decorative covering on golf club handles, stacks of poker chips or for any other purpose in which a protective or decorative covering is desired.

Example II.The same procedure is followed as in Example I, except that of mica is substituted for the titanium oxide in each portion of viscose. A tube of beautiful vari-colored metallic appearance is obtained.

When a die of the form illustrated by Figs. 4 and 5 is used the inner concentric channel is preferably provided with a cellulosic solution which will produce a transparent pellicle whereby the finished tubing will have greatly increased strength than would be the case where an entire cross-section of the tubing contains an opaquing agent or similar material incorporated therein.

Many other variations are possible within the scope of this invention. Any number of difierent- 1y colored or otherwise differently appearin stripes may be produced from two up to a doze: or more. They may be opaque, metallic in ap pearance or transparent or any desired combina tion of these, together with various colors i: combination. It will be evident that the num ber, type and location of the different stripes wiI depend upon the use to which the tubes are t be put.

Our invention has enabled us to produce tube of regenerated cellulose or other non-fibrou sheet material of novel and interesting appear ance having stripes with sharp dividing line therebetween. It has furthermore enabled us t produce tubing of novel appearance having con centric layers and stripes of different optics characteristics. Tubing may be produced havin novel striped appearance without sacrificing th desired strength thereof by providing the sam with an inner layer of transparent materia Tubes produced in the manner described abov may be used in the fiat, collapsed form as rib bons or strips to be used in producing ornamenta effects on packages tied therewith.

Since it is obvious that various changes an modifications may be made in the above descrip tion without departing from the nature an spirit thereof, it is to be understood that the in vention is not to be limited thereto except as se forth in the appended claims.

We claim:

1. The method of forming tubular articles fror freely flowing solutions which are instantly co agulable in a coagulating medium which com prises passing a plurality of such solutions, whil maintaining them separated from each other, t a point closely adjacent said coagulating mediun joining said solutions in an annular stream of sub stantially uniform cross section to form a bon therebetween and maintaining a sharp line 0 division at the joint between said solutions b causing them to flow in parallel relationship t each other prior to coagulation of the same, an immediately thereafter passing said stream int said coagulating medium.

2. The method of forming tubular articles fror freely flowing viscose solutions which comprise passing a plurality of viscose solutions, whil maintaining them separated from each other, to point closely adjacent said coagulating mediun joining said solutions in an annular stream c substantially uniform cross section to form a hen therebetween and maintaining a sharp line c division at the joint between said solutions b causing them to flow in parallel relationship t each other prior to coagulation of the same, an immediately thereafter passing said stream int said coagulating medium.

3. The method of forming tubular articles fror freely flowing cellulosic solutions which are in stantly coagulable in a coagulating medium whic comprises passing a plurality of said solution through substantially parallel passages, whil maintaining them separated from each other, i a point closely adjacent said coagulating mediun joining said solutions in an annular stream c substantially uniform cross section to form a bon therebetween and maintaining a sharp line c division at the joint between said solutions b causing them to flow in parallel relationship t each other prior to coagulation of the same, an immediately thereafter passing said stream int said coagulating medium.

4. The method of forming tubular articles fro! freely flowing cellulosic solutions which are in ntly coagulable in a coagulating medium which iprises passing a plurality of said solutions ough circumferentially separated passages, lle maintaining them separated from each er, to a point closely adjacent said coagulating dium, joining said sections. in an annular 2am of substantially uniform cross section to m a bond therebetween and maintaining a .rp line of division at the joint between said itions by causing them to flow in parallel reonship to each other prior to coagulation of same, and immediately thereafter passing :1 stream into said coagulating medium. The method of forming tubular articles from 21y flowing cellulosic solutions which are inritly coagulable in a coagulating medium, which aprises passing a plurality of said solutions ough concentrically separated passages, while intaining them separated from each other, to oint closely adjacent said coagulating medium, ling said solutions in an annular stream of stantially uniform cross section to form a bond rebetween and maintaining a sharp line of dion at the joint between said solutions by causthem to flow in parallel relationship to each er prior to coagulation of the same, and. imcliately thereafter passing said stream into said gulating medium. The method of forming tubular articles from 21y flowing cellulosic solutions which are initly coagulable in a coagulating medium, which iprises passing a plurality of said solutions ough crcumferentially and concentrically septed passages, while maintaining them septed from each other, to a point closely adjat said coagulating medium, joining said soluis in an annular stream of substantially unirn cross section to form a bond therebetween l maintaining a sharp line of division at the it between said solutions by causing them to v in parallel relationship to each other prior coagulation of the same, and immediately reafter passing said stream into said coagung medium. The method of forming tubular articles from sly flowing cellulosic solutions which are inntly coagulable in a coagulating medium which iprises passing a plurality of said solutions of diiferent optical characteristics, while maintaining them separated from each other, to a point closely adjacent said coagulating medium, joining said solutions in an annular stream of substantially uniform cross section to form a bond therebetween and maintaining a sharp line of division at the joint between said solutions by causing them to flow in parallel relationship to each other prior to coagulation of the same, and immediately thereafter passing said stream into said coagulating medium.

8. A new article of manufacture comprising a thin, flexible, seamless tubing of regenerated cellulose having integrant, longitudinally parallel, circumferential sections, at least one of said sections being transparent, the remaining section or sections having a pigment uniformly distributed within the body of said section or sections to render the same non-transparent, the said tubing exhibiting sharp and distinct lines of demarcation between the said integrant sections.

9. A new article of manufacture comprising a thin, flexible, seamless tubing of regenerated-cellulose having integrant, longitudinally parallel, circumferential and. concentric sections, at least one of said circumferential sections being transparent, the remaining, circumferenfil s'ction or sections havinga pigment uniformly distributed within the body of said section or sections to render the same non-transparent, the said tubing egzhibiting sharp and distinct lines of'd emarc a tiofibetween the said integrant sections.

IOJThe new article of manufacture comprising a thin, flexible, seamless tubing of regenerated cellulose having integrant, longitudinally parallel, circumferential sections, at least one of said sections being transparent, the remaining section or sections having a pigment uniformly distrib uted within the body of said section or sections to render the same non-transparent, the said tubing exhibiting sharp and distinct lines of demarcation between the said integrant sections, and a further section of regenerated cellulose in said tubing concentric with said integrant sections for reinforcing the latter.

LEON PIERRE GEORGES VAUTIER. RENE EDOUARD FAYS.