US1685917A - Process for finishing and coloring paper and paper made thereby - Google Patents

Description

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E,fi8,17 T. HANS PROCESS FOR FINISHING AND COLORING PAPER AND PAPER MADE THEREBY Filed Feb. 21, 1927 ,gugf

flaw 7 3 7 0776 Patented Oct. 2, 1928.

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THOMAS HANS, OF CHICAGO, ILLINOIS, ASSIGNOB TO CONTAINER CORPORATION OF AMERICA, OF CHICAGO, ILLINOIS, A CORPORATION OF DELAWARE.

PROCESS FOR FINISHING AND COLORING PAPER AND PAPER MADE TEEBEBY.

Application filed February 21, 1927. Serial No. 169,856.

This invention relates to a novel and improved process for finishing and coloring paper and to a paper made thereby, and consists of the matters hereinafter described and more particularly pointed out in the appended claims.

My invention as described herein, is directed to improvements in the manufacture of paper used in the making of fibre or'paper board boxes and shipping cases and has par- 1 ticular advantage in the manufacture of heavy multi-ply paper including a colored liner ply; but has advantages also when applied in the manufacture of other heavy paper, as paper of the familiar chip stock without color, as well as in the cases of paper for other uses than for the manufacture of boxes.

In the manufacture of heavy paper used either in making what is familiarly known as corrugated board or in making solid fibre board, a so-called liner sheet is made. This liner sheet consists of a ply, usually colored, butalways containing a large percentage of pure, wood pulp or sulphate and of several plies made from so-called chip, containing the pulp of rags, fibre board, waste paper and the like. I

In the present way of making the liner sheet, after the wood pulp has been broken up (generally and preliminarily in a breaker beater and thereafter in a dump beater) the color is added and mixed therewith in the beater so that the fibrous pulp is thoroughly impregnated with the color. A sizing constituent, as resin, is then added in the beater, with powdered alum, which when beaten up with the colored fibrous pulp, acts to precipitate the size on the colored fibre. Starch in a small proportion (six pounds (6) to a ton of finished board) is then added and mixed with the pulp to give a polished finish to the paper} Thus all the coloring and the full amount of sizing material required to be incorporated in the liner sheet is contained in the fluid fibrous pulp when it is sent to the paper-making machine and all the fibrous material constituting the entire thickness of the colored ply' of the paper sheet contains the full amount of color and size.

a process in which the amount of color required to give a certain tone effect of that color to a liner sheet is materially reduced, thereby greatly reducing the cost heretofore The objectof my invention 'is to produce of making liner sheets having a predetermined desired or specified depth of color.

Another object of the invention is to produce a process by which paper with an improved waterproof finish is made-a paper which has greater resistance to the penetration or absorption of water and on which a more brilliant and outstanding effect may be produced by the usual printing or lithografiphmgprocesses-and this at a reduced cos Another object of the invention is to produce a waterproofing process in which a sav ing in cost of production results from the fact that more moisture may be retained in the paper stock when it is passed on to the calendering rolls, thus reducing the amount of heat required in drying the paper sheet on the drying rolls.

Another object of the invention is to produce a waterproofing process, which even in the case of chip stock, will produce a paper such that when passed through the silicate solution in the manufacture of fibre board, will be capable of taking up or absorbing less water so that only that part of the silicate which may be received and retained on the surface will be picked upfrom the silicate solution, with the result that a large saving is made in the amount of silicate used, without loss of efficient adhesive effect of the silicate. In connection with the invention I have produced a waterproofing solution adapted for use in carrying on the aforesaid process, which solution may be preparedin amounts required for a. days run of the paper-making machine or may be prepared in larger quantites in advance and stored in vats or barrels ready for use when required. This solution is claimed in another application.

In carrying out my process in the preferred way, I introduce only a part ofthe color, heretofore required to produce the desired depth to the calendering rolls, (where fresh water is now applied, after the paper stock has been dried, to facilitate the operation of the calendeling rolls), a colored, waterproofing liquid is applied to the liner face of the paper sheet, which liquid at once Waterproofs and at the same time produces the desired color tone or depth of color on the outside surface of the color ply of the liner sheet.

The coloring and waterproof material applied at the point above noted is a fluid mixture containing an emulsion of paraflin (made from an oil, so-called, and from paraffin) and preferably tapioca powder. The mixture is made in the following manner. The paratlin is first heated to about one hundred and forty (1&0) degrees Fahrenheit and the so-called oil is then added and stirred into the paraffin. This produces what may be called an emulsion of para-flin. In the meantime a large mixing vat is partly filled with cold water and tapioca flour is added and stirred in cold. The solution of tapioca flour and water is then heated to about one hundred and fifty (150) degrees Fahrenheit which brings the solution into the form of a heavy paste. The paraffin emulsion is then added and stirred into this paste after which. the paste is brought to about one hundred and eighty (180) degrees F ahrenheit. Then water is added and stirrcdin to dilute the pas a and the mixture isthen kept at one hundred and twenty (120) degrees Fahrenheit by steam or otherwise. The color is then dissolved and stirred into the dilute paste although if desired the color may be added before the paste is diluted. The dilute solution of color and size is then applied to the advancing sheet of paper on the color ply face preferably in the same way and at the same point as where the water is now added to said sheet just preliminary to its entrance to the c-alendering rolls.

In the solution, so-called, the colo'r and parafiin appear to be precipitated upon the tapioca fibre and when the liner surface of the advancing sheet receives the film of the dilute liquid containing the colored waterproof solution, a thin coating of colored waterproofed tapioca. fibre is applied to that surface. This liquid remains on the surface instead of drawing into the body of the stock and being thus left on the surface a deeper color tone may be given to that surface by an almost inappreciable amount of coloring matter per ton of paper; and a superior waterproofing finish may be given the paper with a less use of waterproofing material, due to the fact that it is applied to and remains substantially on the surface.

The enormous saving in color alone will be understood when it is said that I have found in actual practice that the same tone effect of a given color may be put in the liner sheet with but about sixty (60) percent of the color heretofore used, the bulk of that being supplied at the heaters with but an inappreciable amount per ton of paper supplied with the waterproofing solution herein-above described. The amountiof resin sizing used is also greatly reduced, twenty-five (25) to thirty percent at least being saved at the boaters.

The resulting paper consists of a sheet including the usual plies of chip stock and a colored and waterproofed, finished liner ply in which but little more than one-half of the original amount of color required for a certain color tone effect is impregnated in the fibre pulp of the color ply and the desired waterproofing and color tone effect .is contained in a thin coating deposited on the outside surface of said color ply.

In order to illustrate the process I attach drawings in which I have shown an apparatus by which it may be conveniently carried out. In said drawings, Figure 1 shows diagrammatically and perspectively the usual set of rolls which succeed the last set of drying rolls of the paper machine and which immediately precede or form part of the calendering rolls,together with mixing vats and devices for mixing and applying the coloring and waterproofing solution; Figure 2 is a view representing a vertical sectional elevation of Figure 1, the plane of the section being intermediate the ends of the rollers; Figure 3 is a fragmentary cross sectional view on an enlarged scale of a liner sheet made by the process.

Referring now to said drawings, 10 indicates the set of rolls of the paper machine where there is generally applied a small percentage of fresh water to both sides of the paper sheet after it leaves the drying rolls in order that it may contain some excess moisture when it starts through the calendering rolls. This is in aid of the calendering process. 11 indicates the paper sheet entwined about the rolls 10; 11*, the liner face of the sheet; and 11 indicates the reverse side of the sheet. 12 and 13 indicate the open troughs or boxes extending parallel to the rolls and each engaged with the surface of the roller with which it is associated in a manner that water or other liquid supplied to the trough will be maintained in a dam against the surface of that roller. It is by means of such troughs that the water for supplying additional moisture to the paper sheet has been heretofore applied. The troughs engage the surfaces of the rolls on the sides opposite to the sides with which the paper strip is engaged; and the liquid in the troughs is picked up by the rotating rolls as they pass in engagement with the liquid dam provided in said troughs and is carried into the angle between each of said rolls and the roll next above so as to contact with the advancing surface of the paper sheet passing about said last named roll.

14 indicates a large mixing vat and 15 a smaller mixingvat located above it, The vat 14 has a discharge outlet 16 which is directed into a straining vessel 17. A pump 18 is adapted to withdraw liquid from the vessel 17 by a pipe 19 and to elevate and discharge it through a pipe'20 into a supply tank 21. Said supply tank has an outlet pipe 22 at the bottom to which is connected apipe 23 for discharging the contents of the supply tank into the trough 12 at one end between the adjacent surface of the associated roller and a board or dam 12' in the trough. Said dam 12 runs nearly the length of the trough parallel to the roller and holds the liquid close against the roller until it reaches the far end of the trough where it is permitted to flow betwen the end of the dam and the proximate end wall of the trough into the back part thereof through which it flows to an outlet pipe 24 which constitutes a return pipe to the pump 18.

By the construction and arrangement of vats, pump and pipes described, a continuous discharge of liquid by gravity from the tank 21 to the trough 12 will be maintained and the supply in the tank 21 will be preserved by the continuous withdrawal by the pump 18 of the contents of the strainer vessel 17 (continuously supplied from the vat 14) and of the liquid returned by the pipe 24 from the trough 12. An overflow pipe is connected to the top of the tank 21 for discharge into the large vat 14.

The trough 12 is used for applying liquid to the liner surface 11 of the paper sheet and the trough 13, for applying liquid to the reverse side 11 of the sheet. The latter trough 13 is supplied with water alone by a pipe 13 in the usual manner. The system of vats, pump and pipes just described is designed for supplying the trough 12 with the colored waterproofing solution which is to give the ,final color tone and the novel waterproof finish to the liner surface 11 of the sheet.

As has already been pointed out, but sixty to sixty-five percent of the amount of color which would be required in the present practice to produce the intended or prescribed color tone is introduced into the fibrous pulp or sulphate at the heaters and but seventy-five (75) percent or less of the resin size and alum now used are introduced at that time. The usual starch for finishing, which is also mixed with the fibre pulp at the beaters. is entirely eliminated.

Thus, after the paper sheet has passed through the driers and when it reaches the rolls 10, the colored liner ply of the paper sheet has but sixty (60) to sixty-five (65) percent of the usual coloring matter con tained therein and but seventy-five (75) percent of the usual sizing. It is thus very pale as to color and much below the color tone it is intended to have. It is also under sized.

I shall describe a convenient method of preparing in the apparatus illustrated the grees Fahrenheit.

coloring and waterproofing solution to be applied at the rolls 10 in an amount required for use in a days run of a paper machine Burning out about sixty (60) tons of paper per First paraffin in the amount of about forty (40) pounds is put into the small vat 15 and is heated by steam pipes or otherwise, not shown, to one hundred and forty (140) de- An oil adapted to emulsify the paraflin is then added. Such an oil containing denatured alcohol, soap, acid and mineral oil may be used for the purpose. This oil is added in the amount of three and one-third (3%) pounds and is thoroughly stirred into the paraiiin. This produces what appears to be and may be called herein, an emulsion of paraffin.

In the meantime the large mixing vat 14 is partly filled with cold water (about two hundred (200) gallons) and tapioca flour in the amount of about seventy-five (75) pounds is added and stirred thoroughly into the water in the vat. Tapioca flour is preferred because of its fibrous nature. Starch may be used in place of the tapioca flour but it is not so desirable because the paraffin tends to separate out. The mixture of water and tapioca powder is then heated to bring it into the form of. a heavy paste,-a temperature of about one hundred and fifty (150) degrees Fahrenheit being generally found sufficient for the purpose.

The warm parafiin emulsion in the small vat 15 is now added to the warm tapioca paste and is thoroughly stirred therein, the mixture in the meantime being brought to a temperature of about one hundred and eighty (180) degrees Fahrenheit. Thereafter water is added in the amount of about two hundred (200) gallons to dilute the mixture to a thin watery, pasty solution which is maintained by steam pipes or otherwise at a temperature of about one hundred and twenty (120) degrees Fahrenheit.

The color may now be mixed in the vat 15, about five (5) pounds, depending upon the color and upon the depth of color tone desired, in enough water to hold it in suspension or solution. It is then stirred into the thin, pasty solution last described, as contained in the large vat 14, so as to thoroughly incorporate it into said solution. We now have the coloring, waterproofing. solution which is to be supplied to the trough 12.

Thecoloring, waterproofing solution is picked up by the surface of the roll 10 associated with the trough 12 and is thereby ap-' plied in a thin film to the liner surface 11 of the paper sheet as said paper sheet passes about the roll above the trough 12. Instead of penetratingor drawing into the fibrous body of the liner ply of the paper sheet, the paraffin and coloring matter, appearing as if precipitated upon the fibre of the tapioca, are

retained as a thin deposit with that fibre upon the surface of said liner ply. Thus, but a minimum quantity of the paraflin, the waterf it isdesired to have.

In Figure 3 this construction of the sheet is illustrated in an exaggeratedform. 26 indicates the several plys of chip stock embodied in the sheet and 27 the colored liner ply of sulphate. At 27 the colored liner ply is shown-as it is before it reaches the rolls 10 and vwhen it has impregnated in its fibres the sixty to sixty-five (65) percent of coloring matter and the approximately seventy-five substantially upon ply-27 as illustrated and does not to any ex tent draw'into the. fibrous body of said ply.

In case of the manufacture of liner sheets 75) percent of resin size.

27 indicates the t in-film of'the coloring, waterproofing solution applied at the rolls 10. This film remains the surface of the color without color or-0f sheets of chip, the waterproofing solution Without the'color is said solution is applied to both surfaces'bf the sheet, in which case the solution is supplied -to the trough 13 as well as and in the same way as heretofore described, to the trough 12.

When a sheet of chip, finished in this way for use in the manufacture of fibre board, is passed through a silicate solution to provide the adhesive by which it is attached to the adacent sheet or sheets, which comprise the board, said sheets will take up much less of the silicate solution than in the case of such sheets made by the processes used heretofore, with a resultant saving inthe amount of silicate so-' lution required. This saving is due to the reduced amount of absorption of moisture by the sheets made by the new process. The silicate, instead ofdrawing into and uselessly penetrating the pores of the sheet, remains on the outside surface or surfaces thereof, where only it is required for efficient adhesion to adjacent sheets. Thus a saving in silicate solution, which is a considerable item in the manu facture of fibre board, results without any deleterious effect on the strength of the resulting board.

The many advantages of the process and the savings and economies in manufacture due to its use, as well as the superior finish of the paper produced thereby, will be manifest to those familiar with the art.

The finishing or waterproofing solution. as has been heretofore stated, instead of being made up for a days run, as described herein, may be prepared long in advanceand may be stored in rats or barrelled for shipment for use at other places than where made. The

Wlll be understood that the invention is in no way to'be limited thereto or thereby except as may be pointed out in the appended claims.

I claim as-my invention:

1. In the manufacture of paper from fluid, fibrous pulp, the process of applying to the surface of the advancing formed paper sheet, after it has been dried but before it has been calendered, a solution containing an emulsion of paraffin.

2. In the manufacture of paper from fluid, fibrous pulp, the process of introducing into and incorporating with the pulp only a part of the required sizing material, and of applying to a surface of the advancing paper sheet, after it has been dried but before it has been calendered, a solution containing an emulsion of paraflin. if 4 8. In the manufacture of paper from fluid, fibrous pulp, the process of introducing into I and incorporating with the pulp only a part used. And in the case of sheets of ch1pthe ofth'coloring matter required for the predetermined color tone and but part of the required sizing material, and of applying to the surface of the advancing paper sheet, after it Q has been dried but before it has been calendered, a solution containing color and an emulsion of paraffin.

4. In the manufacture of paper from fluid, fibrous pulp, the process of introducing into and incorporating with the pulp only a part of the coloring matter required for the predetermined color tone and but part of the required sizing material, and of applying to the surface of the advancing paper sheet, after it has been dried but before it has been calendered, a thin liquid containing in suspension a fine, colored, paraffin bearing fibrous ma terial.

5. In the manufacture of paper from fluid, fibrous pulp, the process of intoducing into and incorporating with the pulp only a part of the coloring matter required for the predetermined color tone and but part of the. required sizing material, and of applying to the surface of the advancing paper sheet,

after it has been dried but before it has been calendered, a. thin liquid containing colored, parailin treated tapioca powder.

6. In the manufacture of paper from fluid, fibrous pulp, the process of introducing into and incorporating with the pulp only a part of the coloring matter required for the predetermined color tone and but part of the required sizing material. and of applying to the surface of the advancing paper sheet,

after it has been dried but before it has been calendered, a thin liquid solution of color, emulsified paraffin and tapioca powder.

color and paraffin precipitated on a pasty 7. In the manufacture of paper in a continuous web or sheet, a process for finishing said sheet which consists in applying a thin solution containing paraifin 'to the surface of the advancing sheet after it has passed the dryin rolls and as or before it enters the calendering rolls.

8. In the manufacture of paper in a continuous web or sheet, a process for finishing said sheet which consists in applying a thin solution of paraffin emulsion to the surface of the advancing sheet after it has passed the drying rolls and as or before it enters the calendering rolls.

9. In the manufacture of paper in a continuous web or sheet, a process for finishing andcoloring said sheet, which consists in applying a thin colored solution containing paraffin to the surface of the advancing sheet after it has passed the drying rolls and as or before it enters the calendering rolls.

10. In the manufacture of paper in a continuous web or sheet, a process fOr finishing and coloring said sheet which consists in applying a film of a thin solution containing base material.

11. In the manufacture of paper in a continuous web or sheet, a process for finishing and coloring said sheet which consists in applying a film of a thin solution containing colored emulsified parafifin pasty material.

12. In the manufacture of paper in a continuous web or sheet, a process for finishing and coloring said sheet which consists in applying a. film of a thin solution containing color, emulsified paraffin and a tapioca powder paste.

13. A multi-ply liner sheet comprising one or more plies of chip and an outer color ply, said color ply having part of the color impregnated throughout all the fibres included in its thickness, and a thin precipitated color coating on its outer surface to produce the intended color-tone.

14. A multi-ply liner sheet comprising one or more plies of chip and an outer color ply of sulphate, the latter ply having a coating of color and paraflin applied in the manufacture of the sheet.

15. A multi-ply liner sheet comprising one or more plies of chip and an outer color ply of sulphate, the latter ply having a coating of color and parafiin precipitated upon tapioca fibre.

16. A multi-ply sheet of paper stock comprising one or more plies of chip and an outer ply of sulphate, the latter having a coating of paraffin applied in the manufacture of the sheet.

17. A multi-ply sheet of .paper stock comprising one or more plies of chip and an outer ply of sulphate. the later having a coating of paraffin precipitated upon tapioca fibre.

18. A sheet of paper stock comprising one or more plies, the outer ply having a coating of paraffin precipitated upon a pasty base.

19. A sheet of paper stock comprising one or more plies, the outer ply having a coating of parafiin precipitated upon tapioca fibre.

20. A sheet of paper stock comprising one or more plies, the outer ply having a coating of color and paratfin precipitated upon a pasty base.

In testimony that I claim the foregoing as my invention, I affix my signature this 19th day of February, A. D. 1927.

THOMAS HANS.

DISCLAIMER 1,685,917.-T7i0 mas Hans, Chicago, Ill. Pnocnss FOR FINISHING AND CoLoRING PA- PER AND PAPER M ADE Trimaran. Patent dated October 2, 1928. Disclaimer filed August 31, 1931, by the assignee, Container Corporation of America.

Hereby enters this disclaimer to claims 1, 7

following words, to wit:

, 8 and 9 in said patent, which are in the 1. In the manufacture of paper from fluid, fibrous pulp, the process of applying to the surface of the advancing formed paper sheet, after it has been dried but before it has been calendered, a solutioncontaining an emulsion of paraffin,

7. In the manufacture of paper in a continuous web or sheet, a process for fin ishing said sheet which consists in applying a thin solution containing paraffin to the surface of the advancing sheet after it has passed the drying rolls and as or before it enters the calendering rolls.

8. In the manufacture of paper in a continuous web or sheet. a process for finishing said sheet which consists in applying a thin solution or paraffin emulsion to the surface of the advancing sheet after it has passed the drying rolls and as or before it enters the calendering rolls.

9. In the manufacture of paper in a continuous web or sheet. a process for finishing and coloring said sheet, which consists in applying a thin colored solution containing paraffin to the surface of the advancing sheet after it has passed the drying rolls and as or before it enters the calendering rolls.

. LOflz'cz'aZ azette September :32, 1.931.]

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