US3512914A - Variegated tissue paper coloring - Google Patents

Description

May 19, 1970 1.. FLEISCHER 3,512,914

VARIEGATED TISSUE PAPER COLORING Original Filed Feb. 8, 1963 BYOZ/ United States Patent 3,512,914 VARlEGATED TISSUE PAPER COLORING Leo Fleischer, Cincinnati, Ohio, assignor to Crystal Tissue Company, Middletown, Ohio, a corporation of Ohio Continuation of application Ser. No. 422,838, Dec. 31,

1964, which is a continuation of application Ser. No.

257,189, Feb. 8, 1963. This application Feb. 17, 1969,

Ser. No. 810,900

Int. Cl. D21h 1/46 US. Cl. 8-7 2 Claims ABSTRACT OF THE DISCLOSURE A method of and apparatus for dyeing a web of paper, particularly tissue paper, into primary bands of different, brilliant, discrete colors extending longitudinally of the web which are separated by secondary bands also extending longitudinally of the web in which adjacent primary band colors are softly blended one with the other.

This application is a continuation of US. application Ser. No. 422,838, filed Dec. 31, 1964. US. application Ser. No. 422,838, filed Dec. 31, 1964. was a continuation of US. application Ser. No. 257,189, filed Feb. 8, 1963.

This invention is particularly directed to a uniquely and very pleasingly colored tissue paper, a method of applying a number of differently colored dyes to create that colored tissue paper, and apparatus for carrying out the method to achieve the end product.

In Franz, US. 1,548,261, there is disclosed a method of and apparatus for producing colored effects upon paper and fabrics by flowing a plurality of streams of differently colored liquids down an inclined surface into a nip created by a pair of opposed surfaces pressured one against the other, thereby forming a pool of different colored liquids in that nip. Presumably the different streams intermix to a limited extent as they flow toward the nip. A web of paper or fabric is then passed through the pool to color the web; therefore, the different colored liquids are contacted with the web as the web passes through the nip be tween the two opposed pressure surfaces. Different apparatus for applying this colred effect are shown in each of FIGS. 1-5 of this patent, but in each case the colored effect is not imparted to the paper or fabric web until that web passes through the colored liquid pool in the nip created by two opposed surfaces pressured one against the other.

Franz also discloses that positive intermixing of the liquids deposited on the inclined surface (whether that surface be a plane A, or a roll C, or an endless band E), may be provided by scrapers, or oscillating or rotating bodies, see page 1, lines 46-47, prior to the liquids reaching the nip to form the liquid pool. That is, such mixing occurs upstream from the nip created between the two opposed surfaces pressured one against the other but, in all cases, the web is still not colored until it reaches the pool formed in that nip. Further, Franz discloses that by acting with compressed air or with a stream of water on the solution collected between the rollers [at the nip], see page 1, lines 43-45, positive intermixing of the liquids at the nip itself, instead of upstream therefrom, may occur.

Without such positive and preliminary mixing operations as vaguely disclosed in Franz, that is, by simply flowing the dyes on an inclined surface toward the nip, it has been my experience that intermixing of the different colored dyes does not occur to a sufficient extent to permit creation of a tissue paper having brilliant, different colored primary bands separated by relatively wide, color intermixed, secondary bands that are softly blended of those colors from which the adjacent primary bands are formed such as is achieved by the method and apparatus hoe of my invention. Further, such a preliminary mixing operatlon 1n the manner incidentally suggested by Franz, whether carried out at the nip of the two opposed surfaces pressured against one another or upstream of the nip on one of those surfaces, is a relatively difiicult operation to control with any reasonable degree of success because of the relatively small volumes of liquid solutions involved. However, with the method and apparatus of my invention product reproducibility is relatively easily maintained and the blending of the primary band colors into relatively wlde, soft, secondary band colors proceeds without the necesslty of air pressure sources, water sources, or complex rotating or occillating bodies such as is disclosed for 1nterm1x1ng purpoes in Franz. Further, no shoft or washed appearance for the secondary band colors results when the Franz method is used.

In Cadgene, US. 1,773,169, a process is disclosed in WhlCh a cloth fabric is colored as it passes through a pool of dyes created at the nip of two felt covered pressure rolls. Here, as in Franz, the pool of dyes is created at the mp of two opposed surfaces presured one against the other, the fabric receiving its coloration only as it passes through the nip formed by those two opposed surfaces. In Neden, US. 1,308,098, there is disclosed a method of coloring a web of paper by also passing the web between two opposed surfaces pressured one against the other, one of which slips relative to the other so that the differently colored liquids pooled at the nip impart colorant to the web as it passes through the nip. In Angier et al., US. 1,882,714, there is disclosed a method and apparatus for coloring sheet material that also involves the creation of a pool of colorant at the nip of two opposed surfaces .pressured against one another. The web is passed through be applied to the web in advance of the line of contact.

at the bite of the roll, see page 1, lines 36-38, it goes on to qualify this statement by saying that it must be discharged on one or more of the [webs] where they converge to form the trough as they pass through the nip of the pressure rolls, page 1, lines 39-49. Such a procedure is illustrated in FIG. 1. In none of these references is there disclosed method steps or apparatus for achieving relatively wide secondary bands having a washed or soft appearance while retaining the brilliance of the primary band colors. Further, the witdh of the blended or secondary color bands formed by these methods is minimal compared to those widths that can be achieved by my method and apparatus.

Experimentation and, recently, prolonged runs on a commercial basis, have shown that the providing of different-colored primary bands and the blending of adjacent primary band colors into secondary band colors achieved by running a web of dye absorbent paper, particularly tissue paper, through a puddle of different colored dyes created at the nip between two opposed surfaces pressured against one another (such as between two pressure rolls), as disclosed in all of the prior art, does not produce a paper having the brilliance in the primary bands of discrete colors and the softness in the secondary bands of blended colors, nor the width of the secondary bands, that is obtained by the method and apparatus herein disclosed.

The present invention is generally related to the same area of the art of the above four patents, but it is spe cifically directed to the problems attendant the production of colored webs of dye absorbent paper like tissue paper that bear uniquely brilliant, differ nt colored primary bands and that are separated one from the other by secondary bands of soft colors blended from the adjacent brilliant colored bands not obtainable by any other method or apparatus disclosed in the prior art noted above. The preferred end product of this invention is a web of tissue paper having a number of longitudinally extending primary bands of brilliant, discrete colors separated by areas or secondary bands in which the colors of adjacent primary bands are softly blended one with the other. In the method of and by the apparatus of this invention, the blending of adjacent primary band colors into secondary bands gives an unusual, soft, washed appearance to those secondary bands similar to that of a Madras cloth after repeated washings. One of the unique features of the method and apparatus of this invention is the retention of the brilliance of the individual colors in the primary bands while yet providing soft, washed secondary bands between the primary bands. Thus, it is toward the problem of retaining the brilliance of the colors in the primary bands, as well as creating and controlling the soft blend in the secondary bands, that the method and apparatus of the present invention is directed.

Otherwise expressed, the objective of this invention has been to provide a method of and apparatus for producing a web of dye absorbent paper such as tissue paper having multicolored primary bands of brilliant discrete colors separated by secondary bands in which adjacent primary band colors are controllably and reproducibly blended into a soft or washed blend without muddying or clouding the colors of the primary bans.

Other objectives and advantages will be more apparent from the following detailed description in conjunction with the drawings in which:

FIG. 1 is a diagrammatic perspective view showing a web of tissue paper being treated in accordance with the method and apparatus of this invention, and

FIG. 2 is an enlarged cross-sectional view taken on the line 22 of FIG. 1.

In the drawings, the numeral refers generally to a web of tissue paper. Preferably this web is a tissue paper having wet strength characteristics so that it can withstand being impregnated by liquid dye solutions without breaking. However, heavier weight papers may be used as long as they are characterized by the ability to quite rapidly absorb dyes to give even dye impregnation of the web such as is achieved with tissue paper. The web moves from left to right as viewed in FIG. 1, and coming from a supply roll at the left (not shown) it passes first over a guide roll 11 that is free to rotate with the moving web. The web then passes underneath a cylindrical spreader bar 12 preferably fixed in position against rotation. Note that no supporting surface is present underneath the fixed spreader bar 12. That is, there is no belt,

roll or the like that is pressured against the spreader bar 12 to create a nip through which the web must pass. From the fixed spr ader 12 the Web passes over the first one of two pressure rolls, designated 13 and 14 respectively. The web then passes down through the nip between rolls 13 and 14. The pressure rolls 13, 14 preferably are horizontally aligned, that is, the axes of each roll 13, 14 are located in the same horizontal plane, to permit creation and use of a continuously changing or flushing pool of wash water 36 in the nip. From the pressure rolls, 13, 14 the web goes to a conventional dryer, not shown, and from thence to a wind-up roll, not shown. Neither the dryer nor the Wind-up roll are shown because they are of conventional design, being similar to those used in conventional staining processes for tissue paper wherein a single color is used to stain the entire web.

In the embodiment shown, five differently colored dyes are employed to stain the web of tissue paper in five discrete longitudinal bands designated 15 through 19 respectively. These different dyes are contained in individual containers designated 20 through 24 respectively. These containers may be conveniently mounted somewhere above the run of tissue paper so that the dyes feed down toward the web by gravity, the specific design of the containers being unimportant to the method and apparatus of this invention. Individual outlet pipes, designated 25 v n 4, through 29 respectively, lead from the individual containers 20-24, the flow from the individual containers into the individual pipes being adjustable and controllable by means of valves designated 30 through 34 respectively.

It is preferred that the lower end of each one of the pipes 25-29 terminates at a point closely adjacent to the surfaces ofthe cylindrical spreader 12 so that the dye solutions are deposited on the spreader bar 12. It is to be noted that in each instance of the pipes 25-29 the low r end of a pipe terminates such that the dye flows onto the fixed cylindrical spreader 12 at a point that is removed from the top center thereof toward the direction of the oncoming web 10' by an amount that places the efflu nt stream of dye between 15 to degrees off the top center of the cylindrical spreader. Further, as shown in FIG. 1, the individual pipes 2529 are placed sufficiently close together that the effiuent dyes run down the side of the fixed cylindrical spreader to merge in a pool or puddle 35 that accumulatesbetween the web of tissue paper and fixed cylindrical spreader 12. The dyes could be deposited directly onto the web upstream of the spreader bar 12 although this is not preferred. The puddle 35 is composed of pure, undiluted dye. In those areas of the puddle 35 between adjacent dyes the dyes are unexpectedly found to substantially blend or intermix as the tissue web passes underneath the spreader bar 12 and as the blend is deposited on or impregnated into the Web. Note that no surface in the form of a belt, roll, or the like is provided to. exert pressure against the spreader bar 12 and, hence, no nip formed by opposed surfaces pressured against one another is created through which the web. must pass as it receives the dye. This method step and apparatus arrangement admits of close control of the widths of the primary and secondary color bands, permits relatively broad secondary color bands to be achieved, p rmits rapid dye impregnation of the paper, and provides even and thorough dye impregnation of the paper. Further, such an arrangement requires no separate mixing means such as air jets, scrapers, blades, water jets, or oscillating or rotating apparatus to mix the dyes preliminary to or simultaneous with their contacting the web for dyeing purposes. This relationship is best shown in FIG. 2. Thus, a pool 35 of the different dye solutions is formed in the upstream nip created by the spreader bar 12 and the web 10, the wide secondary blended bands as well as the primary discrete bands of different colors being imparted to the web at this point.

While the spreader 12 could be mounted for rotation it is preferably fixed in place because it has been found that asmaller volume of dye is needed to stain a given web length a particular shade of a color when the spreader 12 is fixed in place as opposed to when it is permitted to rotate. Further, incomparison with the diameters of the pressure rolls 13 and 14 the diameter of the fixed cylindrical spreader 12 is rather small. It is preferred the diameter be as small as possible to cut down on the drag created between the wet web of tissue paper and the spreader 12. However, the lower limit on the diameter of the spreader -12 is usually limited by the fact that it must maintain its rigidity without bowing during use.

It may be noted that the web 10 travels upwardly in passing from the underside of the fixed cylindrical spreader 12 to the top of pressure roll 13. It may also be seen that the web passes relatively downwardly from the top of the guide roll 11 to the underside of the fixed cylindrical spreader 12. This leaves the underside of the fixed cylindrical spreader 12 as a low point between the top of guide roll 11 and the top of the pressure roll 13. Otherwise expressed, the web 10 of tissue paper does not move in a straight path from guide roll 11 to the top of pressure roll 13 but instead it is depressed between them. Hence, the dyes are applied to the web 10 while it is under tension and held snugly against the underside of the spreader 12, thereby permitting the pool 35 of dyes upstream of the speaker bar to be established.

As the tissue web leaves the fixed cylindrical spreader 12 and passes toward the first of the two pressure rolls 13, 14 there is a run of appreciable length in which the undiluted or pure dyes are permitted an opportunity to further blend one with the other in those secondary bands adjacent different primary bands, and to completely and evenly impregnate the web. Hence, by the term appreciable or extended length of nm is meant a distance sutficient to allow the dyes to evenly and completely saturate the paper; it will be apparent to those skilled in the art that such a distance will vary depending on the type and quality of dye absorbent paper used and the type of quality of the dyes used.

A water flush or web wash is provided at the nip of rolls 13, 14 which is created by the constantly flowing wash water 36. Any excess of dye imparted to the web by the dye pool 35 at the spreader bar 12 is removed at the pressure rolls 13, 14 which rolls essentially function to squeeze out the excess dye. If such squeezings are not flushed from the nip of the pressure rolls 13, 14 a pool of completely intermixed dyes forms which impairs the brilliance of the primary band colors. Further, such a water flush at the nip causes the secondary bands of blended colors to take on a very pleasing soft or washed appearance, thereby creating the Madras effect in the overall appearance of the finished dyed web. Thus, the effect of brilliant primary color bands separated by soft secondary color bands is promoted by (a) the actual fading of those secondary bands due to the squeezing out of dye by the pressure rolls 13, 14 and the washing of those areas by the continuous flush of wash water 36, and (b) the retaining of brilliance in the primary color bands by the constant flow of water stream 37 through the nip of pressure rolls 13, 14 to remove continuously the dye solution squeezed out by the pressure rolls 13, 1 4 which would impair or dull the primary color hands if left unrernoved. It is not fully understood why the pressure roll nip and the water flush tends not to wash out or soften the brilliance of the colors in the primary bands 15 through 19 of the web, or why it tends to add to the fading of the colors in the secondary bands.

Pipe 38 used to provide the stream 37 of Water that is fed into the nip between rolls 13 and 14 preferably is positioned to discharge the stream of water at a point roughly halfway between the two ends of the rolls 13 and 14. The stream is of such a volume that it has a highly diluting effect upon the dyes that would otherwise accumulate within the nip between rolls 13 and 14 to wash or flush thoroughly those dyes from the nip. In the preferred practice of the invention there is a steady, substantial flow of water and mixed dyes from both ends of the pool in the nip between the pressure rolls 13 and 14.

As to the dyes utilized in the method apparatus of this invention, they may be those normally used in an operation wherein a web of tissue paper is stained all one color. It is recommended that the dyes used be either all basic or all acidic so that no reaction occurs between the dyes which might result in a precipitation in those areas in which adjacent colors intermix or blend. Further, the dyes utilized preferably are of the type that penetrate completely through the web as quickly as possible upon initial wetting so that opposite sides carry identical colors just as in a conventional single color staining operation. One main consideration is that the pure undiluted dyes remain upon the web during that part of the run shown in bet-ween the spreader bar 12 and the pressure rolls 13, 14, and that this run be sufficiently long for the individual colors to have an opportunity to completely saturate the Web of tissue paper prior to passing through the nip of pressure rolls 13, 14 and the water flush that exists at this pressure roll nip.

Having described the preferred embodiments of my invention, I claim:

1. A method of coloring a web of tissue paper with primary bands of different discrete colors separated by secondary bands of blended colors, the blended colors being blends of adjacent primary band colors, comprising the steps of,

continuously pressuring said web against a spreader bar to create a nip defined solely by said web and said bar,

running a plurality of differently colored streams of dyes into said nip to form a single liquid pool at the upstream nip of said spreader bar and said web.

permitting said web to move an extended distance between said spreader bar and a set of pressure rolls to permit said dyes to completely saturate said Web prior to entering the nip of said pressure rolls, and

running a water flush into the nip of said pressure rolls of a sufficient volume to highly dilute squeezed out dyes accumulating therein, said highly diluted dyes being permitted to run freely from the nip.

2. The method of claim 1 wherein said dye streams are deposited on said spreader bar at spaced points along its length, said dyes running from said spreader bar onto said Web.

References Cited UNITED STATES PATENTS 1,410,344 3/ 1922 Ornstein 814 1,548,261 8/1925 Franz 814 XR 1,882,714 10/ 1932 Angier et al.

DONALD LEVY, Primary Examiner US. Cl. X.R. 8-14 UNITED STATES PATENT OFFICE FERTIFICATE OF CORRECTION Patent No. 3 512 I Dated June 23 1970 I t Leo Fleischer It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, Line 24, "continuation" should read c0ntinuationinpart SIGNED mu smtn OCT 6 Attest:

A Offi mm 1:. saaumm, .111. mg Comissionar of Patents FORM F'O-YOSU (10459) uscoMM DC eoansd eg u s GDVUINMENT nmmnc OFFICE nu o-Jss-sn

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