US1805013A - Method for making fast colored crepe paper - Google Patents

Description

May 12, 1931. G. H. SAYLER 1,805,013

IBTHOD FOR MAKING FAST COLORED CREPE PAPER Filed May 16, 1929 Patented May 12, 1931 UNITED STATES PATENT OFFICE GALEN H. SAYLER, OF CHICAGO, ILLINOIS, ASSIGNOR TO DENNISON MANUFACTURING COMPANY, OF FRAMINGHAM, MASSACHUSETTS, A CORPORATION OF MASSACHU- SETTS METHOD FOR MAKING FAST COLORED CREPE PAPER Application filed May 16, 1929. Serial No. 363,553.

This invention relates to a method for making colored crepe paper (more especially from light weight papers or tissues) which is non-bleeding or relatively fast, and to the resulting product.

In the art as heretofore known and practiced, it has not been accomplished to make a crepe paper of brilliant coloration which also retains its color upon becoming wet. As a consequence, in subsequent steps of manufacture or in the course of using such products it has been necessary to avoid any appreciable contact with moisture, since the coloring matter is readily dissolved and removed.

Even slight dampness causes the dye to bleed and may in turn effect the dyeing of other materials, with which it comes into contact, more permanently than the paper, while excessive moisture or repeated wetting will largely dissolve and remove the color from the dyed sheet.

The procedures hitherto available for dyeing paper have consisted in either dyeing the pulp from which the paper was subsequently to be made or passing the paper through a bath of dye (or between calender rolls wet with the dye) followed by subjecting it to the usual operations for creping.

Paper made by merely dyeing the pulp in the beater is generally not entirely satisfactory for the subsequent operations required for creping on account of the tendency for the dye to go into solution in the creping bath. Furthermore, if it be attempted to render the colored pulp resistant to water, as by mordanting, this results in depositing an insoluble color lake upon and between the 1 ers, thus more or less filling the interand coverin the surface of the fibers with a superficial insoluble layer of the dye. Not only is such a result uneconomical of dye but the colors thus obtainable are dull and lustreless. Moreover, only a relatively small portion of the dye being combined within the fibers, an appreciable proportion is retained only b virtue of its mechanical adhesion to the ber surfaces.

This dullness of color is attributed to the fact that surface deposits of color substances are not susceptible of presenting a high decompletely contained within the fibers,,and which shall be non-bleeding or relatively gree of lustre or brilliancy of color. On the other hand, transparent colored material, has an inherently bright color value and also possesses an additional surface lustre or sheen. These conditions in fact obtain with individual cellulosic fibers which have been dyed with a cellulosic-soluble dye but such fi ers, as dyed in accordance with prior practices of the art, have been overlaid by adherent coatings of the solution which upon drying leave a deposit of dye which somewhat impairs such brilliancy. Moreover, when it has been attempted to mordant the dye, as in beater dyeing, this superficial coating has been rendered insoluble and relatively opaque and dull, and hence the obtainment of bright colors and resistance to moisture have been heretofore diametrically opposed factors in the art of making colored paper, and more especially so when undertaken in conjunction With the creping operation. It is therefort desirable to decrease so far as possible or practicable the surface deposit of dye and at the same time to provide a suflicient amount of color substance adsorbed or dissolved within the. cellulosic fibers to produce the desired color shade, and tofix it therein.

It has also been practiced to carry the paper through a dye treatment, either by passing the sheet through a solution of the dye, or between calender rolls adapted to apply the solution thereto, and then running the sheet throu h a creping bath or using a single creping ath containing the dye therein, followed by creping from the surface of a heated roller in the customary manner of procedure for obtaining the result. But the product as by former practice contains dyes which are in large part water soluble so that they are easil removed upon subse quent wetting or by ampness.

It is therefore an object of this invention to make a colored crepe paper in which the colors shall be brilliant and substantially or fast with respect to the action of moisture thereon. It is a further object that the process shall be economical of time, labor and coloring materials and also that the product may be given both fineness and a high crepe ratio, as hereinafter to be explained. Further objects .of the invention will appear from the following disclosure. I

In brief, and as representative of its more essential elements, the method of the invention includes the steps of treating a sheet of paper with a solution of a dye and with a fixing reagent (with or without intermediate removal of excess of the first solution and/or drying of the sheet, and either in the sequence stated on -in the reverse order or simultaneously) followed by creping the dyed sheet, preferably while still wet or damp from the previous stage of treatment. The liquid used in the second treatment may also conveniently serve the additional function of a creping bath.

The dye may be any suitable dyein cornpound of the desired .color so long as it does not manifest any deleterious action upon the pa per and is capable of thoroughly and 'uniformly wetting and permeating the cellulosic fibers of the same. Basic dyes are ordinarily to be preferred and it is further generally desirable that the dye shall not be affected by nor in turn corrode the apparatus employed.

For example, for an orange coloration of the paper the following dye solution has been found eminently satisfactory:

Auramine O concentrated colour index No. 655 32 ounces, rhodamine 6 .G ex colour index No. 752 14 ounces, water 60 gallons; while for green Aurarnine O concentrated colour index No. 655 60 ounces, methylene blue (zinc free) 80 ounces, water 60 gallons,- gives good results.

The fixing reagent will of course de end 7 primarily upon the dye which is to be 'xed desirable that it should not react appreciably or rendered insoluble and permanently associated withthe paper sheet In addition, it is with the apparatus nor be affected thereby,

unless the apparatus beprotected to prevent such reaction.

It is also desirable for some purposes that the fixing reagent and its reaction product with the dye within the pa- Der fibers shall be relatively transparentor translucent ratherl than opaque solids, so thatthe full color value and brilliancy of the fixed dye may be effective -F or the purposes of the present Invention, however, it is essential that neither the dye or fixing agent shall seriously impair the ereping operation. The creping operation,-

In general and more especially when making a closely folded or finely creped paper,

- requires the provision of firm adhesion-'toa smooth surface or creping roll from which the paper is subsequently removed by a scraper or doctor blade, the paper leaving the roll as the pressure of the doctor blade exceeds the strength of the adhesive The plaited or creped effect is imparted to the paper as the successive portions of the sheet thus crinkled up leave the roll. To effect this result an adhesive such as glue, dextrine or the like is 'added to that solution from which the sheet passes to the creping operation Accordingly, for the purposes of the present invention it is important that neither the dye nor fixing agent shall seriously impair the adhesion of the paper to the roll nor react with the adhesive material employed; In other words, the several reagents should be mutually compatible. It is further advantageous if the adhesive may be freely admixed, in the requisite proportions, with the dye solution or, more desirably, with the solu-' tion of fixing reagent, without precipitation or other adverse effect upon. either reagent and without deleterious effect upon the properties of the resulting solution. The latter may thereby serve the two-fold purpose of a dyeing or fixin solution as the case may be and of a creping bath.

A fixing reagent which is especially approand other reagents of like characteristics.

Atypical and preferred application of the invention will be described with respect to the production of a high crepe ratio or a closely creped tissue paper, or both, by means of the apparatus illustrated in the accompanying drawing, in which Fig. 1 is a side elevation of apparatushaving the rubber rollers superposed for applying the dyeing andmordanting solutions to the paper simultaneously, upon opposite sides of the sheet.

The paper used is preferably light wei ht or tissue paper and is-advantageously nished with a smooth side suchv as that produced by passing over a hot calender surface in the original manufacture thereof. It is also desirable that the sheet shall be readily wet and penetrated by liquid and that the individual fibers shall be rapidly saturated by the dye solution to be used, but that it shall not absorb and retain large volumes of the solution. A still further helpful though not essential qualification is that the sheet shall be relatively strong both while wet and while dry. 1

Preliminary to the operation of the apparatus, the sheet of paper 1 is drawn from roll 2 passed through the nipof superposed rollers 3 and 4-to the drying drum 5, thence over the drum tothe doctor blades 6 from which dip into the dye solution contained in tank 7 4 and the roller 4 is mounted in contact with an intermediate roller 9 which in turn contacts with roller 10, the latter dipping into the solution of fixing and/or creping reagent contained in tank 8. A blower 11 for drying the sheet which asses over drum 5 may also be provided an suitable heatin arrangements may:1 be provided for heating t e drum 5 if de- Slle In order to reserve the finished side of the sheet until a ter the creping operation and also to develop and retain the sheen therefrom in the finished product, it is preferable to brin this side into contact with the smooth crepmg surface employed (which is preferably also heated).

The gathering apparatus or re-winder may be positively driven and it is usuall preferable that the heavier rollers of t e series should also be positively driven, in proper relation with each other and without creating unequal strains upon the sheet either while wet or dry, but more especially while wet.

The dye solution (such as that prepared according to the formula above given) is then supplied to tank 7 while a solution of an appropriate mordanting reagent is added to tank 8, preferably katanol-o of a concentration of 2% more or less, in water, for example.

' To the latter bath is added a small amount of adhesive, thereby rendering the mordanting bath of suitable properties for use as a crep ing bath also. The adhesive may consist of glue, dextrine, or like substances, which are soluble in water, adhesive, and not adversely affected by the mordanting reagent. It will be clear that, if the mordanting reagent be applied first (as from tank 7) and the dye solution second (as from tank 8) the adhesive or creping reagent may be added to the dye bath. It may also be practiced to add t e creping reagent to the first bath but ordinarily this order of procedure will result in disadvantages and inconveniences.

In operation, the sheet of tissue paper is drawn from a supply roll 1=and passed between the applying rollers 3 and 4 which apply the dye solution to the under surface and the mordanting solution to the upper surface, simultaneously. In this mode of procedure, b suitably controlling the space between the mp of the rollers, the aggregate amount of dye and fixing solutions taken up by the sheet may be controlled and reduced to a very low minimum, if desired, to effect economy of materials, to leave the paper product soft or to produce light shades. But thepressure exerted at this point also effectively promotes the penetration of the solutions into the fibers of the sheet, and upon the release of this pressure and the expansion of the sheet as a whole, the two solutions are left within the fibrous cellulosic structure where they react to form an insoluble dye substance. If the fixing reagent solution contains an adhesive, and the drum 5 is heated, the sheet may be passed over the drum and partially dried, and creped by a doctor blade 6' and gathered in any convenient way. If the paper is to be left uncreped, a simple off-take roller (not shown) may be used, similar to roller 2, and the d-yed sheet taken up in this condition.

The colored crepe paper thus produced by either treatment is characterized by being susceptible of possessing either a high crepe ratio or a fineness of crepe texture or both and also by its brightness of color, a brilliant sheen and marked uniformity in both texture and appearance. These properties are further enhanced by employing tissues having a finished surface, but they are primarily to be attributed to the penetration of the fibers by a large proportion of the dye solution and the fixation of the thus adsorbed dye, and to the removal of a large part of the superficial deposits of dye from the surface of the sheet.

Accordingly, the relatively dye free cellulosic surfaces retain their lustre or quality for acquiring a lustre, and the total of reflected and transmitted light is thereby greatly increased, resulting in the marked brilliancy of the colored paper.

Whatever the true explanation of the several desirable properties and qualities manifested by paper colored and creped in accordance with the invention, it is sufficient to state that in general a much more satisfactory and desirable product is attained by this procedure, that it may be controlled and produced at will upon an industrial scale of operations, and that it constitutes a product not hitherto known to the art.

It will be apparent that numerous changes may be made in the procedure of the invention and in the raw materials and reagents used, when it is applied in actual practice and adapted to the varying conditions of operation and for the production of different qualities and kinds of products desired, such changes and modifications are however, to be considered as comprehended by the above disclosure and included within the terms of the following claims.

I claim:

1. A method for making non-bleeding colored paper, which comprises treating avsheet of paper simultaneously with a dye solution and with a solution of fixing reagent.

2. A method for making non-bleeding colored crepe paper, which comprises treatmg a sheet of paper simultaneously with a dye solution and with asolution of fixing reagent and thereafter creping the sheet.

3. A method for making non-bleeding colored paper, which comprises treating a sheet of paper, under pressure, simultaneously on opposite sides of the sheet with a die solution and with a solution of fixing reagent.

Signed by me at Chicago, Illinois, this eighth day of May 1929.

GALEN H. SAYLER.

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