US3360393A

US3360393A - Method of making cockled paper

Info

Publication number: US3360393A
Application number: US363774A
Authority: US
Inventors: Cecil R Rhorer
Original assignee: Kimberly Clark Corp
Current assignee: Kimberly Clark Corp
Priority date: 1964-04-30
Filing date: 1964-04-30
Publication date: 1967-12-26
Anticipated expiration: 1984-12-26

Description

Dec. 26, 1967 C. R. RHORER METHOD OF MAKING COCKLED PAPER 2 Sheets-Sheet l Filed April 30,1964

Sheet, 2

. l 111 1 gi A Q (L C- R. RHORER METHOD OF MAKING COCKLED PAPER Dec. 26, 1967 Filed April 30, 1964 2 Sheets United States Patent ABSTRACT OF THE DISCLOSURE A paper cockling apparatus including a rotating roll having depressions in its peripheral surface for holding water for transfer onto separated spots of a paper web passing over the roll and drying apparatus for drying the paper web as so wetted.

The invention relates to the manufacture of paper and, more particularly, to a method and apparatus for producing a paper having a cockled finish.

Prior to my invention, cockle finished paper has generally been made off or separate from the papermaking machine. Previously manufactured, smooth finished, paper has been drawn from reels through a size bath; and the paper has then been air dried, such as by means of the well-known festoon drier which supports the paper in the form of loops between traveling spaced rods. The cockles in the paper, which are spots that are warped or bulged from the general plane of the sheet, are produced on account of excessive and uneven shrinkage during drying.

It is an object of the present invention to provide an improved method and apparatus for manufacturing cockled paper which does not require air drying, such as by means of the festoon drier, and Which is, therefore, considerably more economical to use than prior methods and apparatus.

In brief, according to the invention, it is proposed that cockle finished paper be produced by applying measured quantities of water onto a paper Web in spots that are irregularly spaced, sized and shaped and they drying the web, preferably by passing the web through a conventional drier drum section. Preferably, the web is drawn through a sizing bath before the application of the water, and preferably the water is applied in such irregular spots by means of a yieldable roll having an intaglio peripheral surface, the surface including irregularly spaced, sized and shaped spots etched out of the roll surface for carrying measured amounts of water within them for application onto the web.

The invention consists of the novel methods and constructions to be herein-after described and claimed, for carrying out the above stated objects, and such other objects, as will be apparent from the following description of a preferred mode of practicing the invention, illustrated with reference to the accompanying drawings, wherein:

'FIG. '1 is a fragmentary, diagrammatic, side elevational view of a portion of a papermaking machine incorporating Like characters of reference designate like parts in the several views.

Referring in particular to FIG. 1, the cockling mechanism of the invention may be seen to comprise a cylindrical roll which has a resilient peripheral surface and a which has a nip with a relatively nnyieldable cylindrical the apparatus of the invention for producing cockled paper and which includes a pair of nipped rolls, one having a yieldable intaglio surface;

FIG. 2 is an end view of the nipped rolls, together with a supporting frame;

FIG. 3 is a side view of the rolls and associated struc- 7 FIG. 5 is a fragmentary, longitudinal, sectional view of the intaglio surfaced roll.

backup roll 11. The nipped

rolls

10 and 11 are disposed in a papermaking machine between a bank 112 of can driers and a second bank 13 of can driers. The drier bank 12 comprises a series of cylindrical, rotatable, steam heated drier drums, including the illustrated

drums

12a, 12b and 12c. The drier bank 13 comprises a series of cylindrical, steam heated, rotatable drums, including the illustrated

drums

13a, 13b, 13c and 13g.

A horizontal size press 14 is located over the

nipped rolls

10 and 11, and the size press comprises a pair of rolls 15 and '16 having a nip between them. A source of paper sizing, which is made up principally of starch and water, is connected to provide a pond 17 of the sizing in the nip between

rolls

15 and 16.

A paper web W is carried by the drums 12a, 12b and 120. Suitable guide rolls are provided for the web W, and, as illustrated in FIG. 1, these comprise a guide roll 18 for directing the web W between the

rolls

15 and 16 and

guide rolls

19 and 20 for receiving the web W from the rolls 10 and '11 and for directing the web around the drier drum 13a.

The web W, after leaving the last can drier 13g, may be passed through a calender stack 21 to a winder 22. The calender stack 21 is of conventional construction and, as shown, comprises a pair of

steel rolls

23 and 24 between which the paper Web W passes, and the winder 22 is also of any conventional construction.

The roll 11 is suitably mounted so as tobe rotatable on a fixed axis. The roll 10 is rotatably mounted with respect to a fixed frame 25, and a doctor blade 26 is also mounted with respect to the frame 25 so that the blade 26 is in doctoring relation with respect to the peripheral surface of the roll 10. The blade 26 is carried by a blade holder 27 disposed on a pair of

opposite shafts

28 and 29. The shafts '28 and 29 are rotatably mounted in bearings 30 which are fixed within bearing housings 31.

The bearing housings 31 are adjust-ably disposed in receiving cavities '32 provided in a fixed frame 3 3, and adjusting

screws

34 and 35 hold the bearing housings 31 in proper vertical positions within the cavities 32.

Arms 36 are fixed onto the shafts 2'8 and 29, and these arms are connected by means of links 37 with convention-a1 mechanism 38 for adjustably fixing the ends of the links with respect to the frame 25. The connections between the links 37 and the arm-s 36 are sufficiently loose so as to permit longitudinal oscillation to a slight extent of the blade 26 and of

shafts

28 and 29 in the bearings 30.

The blade 26 is oscillated 'by means of a motor '39 of conventional construction which has a swinging oscillating arm 40 on its exterior. A bell crank 41 is pinned to the arm 40 at one end of the crank and has a pin and slot connection 42 at its other end with the shaft 28.

A water pan 43 is disposed beneath the roll 10 and beneath the blade 26 and blade holder 27. A water shower pipe 44 is fixed to the bottom of the blade holder 27 and has outlets for spraying water onto the surface of the roll 10 beneath the blade 26.

The various can driers 12-12c and l3a-13g in the banks 12 and 13 are driven from any suitable source of power, and the

rolls

10, 11, 15, 16, 23 and 24 are also preferably driven. The roll 10 is driven from a suitable power source by means of a coupling 45.

The backup roll 11 has a relatively hard peripheral surface, and the roll 10 has a relatively soft peripheral surface. The surface of the roll may, for example, have a hardness of 120, Pusey & Jones Plastometer (Ms inch ball). The roll 10 is provided on its outer surface with a plurality of spaced discrete indentations 10a, which may, for example, have depths of about .006 inch. The peripheral surface of the roll 10 is otherwise cylindrical, so that the doctor blade 26 has a smooth running contact with the roll 10 as the roll turns. The roll 10, thus, may be considered to have an indented, intaglio, cylindrical surface.

The intaglio outer surface of the roll 10 may, of course, be formed in a number of ways. One manner of forming that has been found successful includes the use of a plane zinc plate which is etched with the pattern that is intended to be provided on the surface of the roll 10. A paper mat is applied onto the zinc plate after etching in order to make a mold for molten rubber, and the molten rubber is then poured onto the zinc plate and is set. A relatively thin molded rubber mat of about A; inch thickness, for example, is thus obtained from the zinc plate; and this is applied and is caused to adhere by suitable gluing composition on the exterior surface of the roll 10 which is otherwise of relatively hard material, such as hard rubber. A is apparent from FIG. 4, the indentations 10a in the yieldable surface roll 10 are, preferably, of haphazard shapes; however, they may, for example, be about A; inch width and /2 inch length. The roll 10 may, for example, have an 18 inch diameter, but its diameter is not critical. The roll 10 has a length slightly greater than the width of the web W, and may, for example, have a length of 120 inches with an 18 inch diameter, without excessive bending of the roll in operation (in this connection, it may be noted that the roll 10 is illustrated in FIG. 4 as being of less length in relation to its diameter than just given, and that the indentations 10a are shown larger with respect to roll diameter than has been mentioned above, these variations being only for the purpose of better illustration).

In operation, the web W passes over the driers of the bank 12 and is in substantially dry condition. The web W then passes through the horizontal size press 14, between the

rolls

15 and 16 and through the size pond 17, and is thus substantially wetted with size. After such passage through the size press it may, for example, consist of about 50 percent moisture. The web W then passes between the

rolls

10 and 11. The intaglio roll 10 is preferably driven from the coupling 45 to have the same peripheral speed as the linear speed of the web W, and during its rotation the indentations 10a receive water from the pan 43 and from the shower 44. The pan 43 preferably maintained partially filled with water so that the roll 10 is partially immersed in water as it turns through the pan 43. The doctor blade 26 doctors off substantially all of the water on the portions of the peripheral surface of the roll 10 between and bounding the indentations 10a, and each of the indentations 10a receive and hold bodies of water which are limited in depth by the bottoms of the indentations and by the blade 26 passing across the indentations 10a and which are thus of substantially the same depth as the indentations. The water held by the indentations 10a passes onto the relatively moist wetted web W from the horizontal size press 14 as the web W passes between the

rolls

10 and 11, and this action is accentuated by the fact that the

rolls

10 and 11 are under substantial pressure so that distortion of the relatively yieldable surface of the roll 10 takes place. A significant portion of the water, for example, about half of the water, contained by the indentations 10a, thus, transfers onto the web W, although the indentations retain a small amount of water after turning through the nip of the

rolls

10 and 11. The effect of the intaglio roll, thus, is to add additional water onto areas of the web W which pass over the haphazardly shaped and spaced indentations 10a and which areas are thus of haphazard size and shape; and the rest of the roll surface that has been doctored substantially free of water 4 does not provide any substantial additional wetting of the web.

The web W passes from the

rolls

10 and 11 onto the driers of the drier bank 13, and these driers again dry the web so that it contains about 5 to 10 percent moisture, which is that dryness that finished paper web ordinarily has. The wetted spots of the web W that have passed over the indentations 10a dry later than do the other portions of the web W, and this retardation of drying of the haphazardly spaced and shaped web portions has the effect of producing a relatively rough, uneven paper web which is substantially the same as that produced by the lofting operation previously mentioned.

The thickness of the doctor blade 26 or the pressure which it bears on the surface of the intaglio roll 10 does not seem particularly critical; however, it has been found, for example, that a blued steel blade having a thickness of .012 inch which protrudes behind its holder 27 by about 2 inches is quite satisfactory. The shower 44 need not be used during ordinary operation of the intaglio surfaced roll 10, since the indentations 10a fill with water while passing through the pan 43; the shower 44, however, may be very useful in cleaning out the indentations 10a. It is contemplated that sizing solutions may also be supplied to the pan 43, if desired; and in this case, in particular, it is desirable to use the shower 44 for cleaning out the indentations 10a.

The intaglio surfaced roll 10, thus, advantageously applies additional water to the previously sized, moist web W in discrete areas which dry later than the other areas of the web as the web subsequently passes through the drier bank 13. The roll 10, thus, has the effect of printing water onto the previously sized web W in discrete areas in metered amounts, similar to the printing action of a rotogravure printing roll using ink, thus slowing down the drying in those areas of the web in which the water is transferred from the indentations 10a. A cockling effect of the resultant paper web is thus obtained without the use of expensive lofting apparatus.

I wish it to be understood that the invention is not to be limited to the specific constructions and methods as above described, except only insofar as the claims may be so limited, as it will be understood to those skilled in the art that changes may be made without departing from the principles of the invention. In this connection, it will be apparent that the intaglio surfaced roll 10 may have a relatively hard surface instead of a soft surface as mentioned above. With this change, the roll 11 would be provided with a relatively soft surface instead of a hard surface. With these modifications, the roll 11 will yield in the vicinity of the nip between the

rolls

10 and 11, while there will be substantially no yielding of the roll 10; and the soft surfaced roll 11 will assure intimate contact of the paper with the water containing cells 10a in the roll 10 to provide substantially the same application of water to the haphazardly spaced areas of the web as previously described.

What is claimed is:

1 In a method of making cockled paper, the steps which comprise, running a web of paper over the outer surface of a rotating roll that is provided on its surface with spaced depressions, preliminarily filling said depressions with water before application of the web to the roll so that the water transfers onto the paper web from the depressions as the web travels over the roll, and then drying the paper web.

2. In a method of making cockled paper, the steps which comprise, applying sizing onto a traveling web of paper, thereafter passing the web of paper over the outer surface of a rotating roll that is provided on its outer surface with irregularly sized, spaced and shaped depressions, preliminarily filling said dperessions with water before the roll surface contacts the web so that the water within the depressions transfers onto the paper Web, and then drying the paper web.

References Cited UNITED STATES PATENTS Hampson 29121 X Arpin 162-112 Yanes 101-170 Pearson 118262 Snowman 11738 MURRAY KATZ, Primary Examiner.

Claims

1. IN A METHOD OF MAKING COCKLED PAPER, THE STEPS WHICH COMPRISE, RUNNING A WEB OF PAPER OVER THE OUTER SURFACE OF A ROTATING ROLL THAT IS PROVIDED ON ITS SURFACE WITH SPACED DEPRESSIONS, PRELIMINARILY FILLING SAID DEPRESSIONS WITH WATER BEFORE APPLICATION OF THE WEB SO THE