US3565756A - Apparatus for the continuous manufacture of patterned paper - Google Patents

Abstract

LIQUID STOCK IS UNIFORMLY DISTRIBUTED ON A MACHINE WIRE CLOTH. THE THUS FORMED WEB IS CONVEYED UNDER AND IN CLOSE PROXIMITY WITH A PATTERNING BELT. SHOWER PIPES EJECT A WATER SPRAY THROUGH THE PATTERNING BELT AND FORMED WEB. A METALLIC SCREEN, POSITIONED BETWEEN THE SHOWER PIPES AND THE PATTERNING BELT, DISTRIBUTES THE WATER SPRAY UNIFORMLY THROUGH THE PATTERNING BELT.

D R A W I N G

Description

23, 1971 SUSUMU KASHIWABARA ETA!- 3,565,756

APPARATUS FOR CONTINUOUS MANUFACTURE OF PATTERNED PAPER Filed March 6, 1968 I 2 Sheets-Sheet 1 Isa FIGQII Feb. 23, 1971 SUSUMU KASHIWABARA ETAL APPARATUS FOR THE CONTINUOUS MANUFACTURE OF PATTERNBD PAPER Filed March 6, 1968 2 Sheets-Sheet 2 FIG.-2

FIG.3.

United States Patent U.S. Cl. 162297 3 Claims ABSTRACT OF THE DISCLOSURE Liquid stock is uniformly distributed on a machine wire cloth. The thus formed web is conveyed under and in close proximity with a patterning belt. Shower pipes eject a water spray through the patterning belt and formed web. A metallic screen, positioned between the shower pipes and the patterning belt, distributes the water spray uniformly through the patterning belt.

This invention relates to a device for the continuous manufacture of patterned paper, and more particularly, to a device for imparting desired patterns on paper with perforations or cavities formed by means of water jets during paper machining.

Paper with a pattern of perforations or undulations has been manufactured in two steps, i.e. a first step to manufacture the paper per se and a second step to apply a pattern thereon by pressing patterns or boring through holes. This is not only inefiicient but also the pattern formed thereby is stiff, crude and not of desirable appearance. In view of the fact that paper is increasingly used as a substitute for textile cloths, such as towels, table cloths, napkins, dresses, sheets, bed covers, etc., there has been a strong demand for an industrial method and device for inexpensively producing paper having a feeling similar to that of conventional textile cloths and with neatly appearing patterns. However, it may be safely said that such need for the industrial method and device has not yet been met successfully, nor has production of the paper having satisfactory feeling for the use in lieu of textile cloths been completed, and hence, no such a paper is on market.

Therefore, an object of the present invention is to provide a device for a continuous production of patterned paper to be used for the purposes as referred to. According to the invention, a wet-web prepared by removing approximately 90% of the water content of the liquid stock in the machining process is patterned by jetting water through perforations of a patterning belt means driven proximate thereto and at the same speed, and the wet-web thus patterned is then dried. The patterned paper thus dried, may be subjected further to a mechanical cockling treatment to make the paper shrinkable by means of an embossing roll, dry creping, wet creping, and the like, depending on the use of the product. It is also possible to apply a chemical softening treatment by using a surface activating agent, such as fatty acid amine, alkyl amine, and the like. According to the present invention, it is also permissible to mix non-heat-shrinkable paper fibers with more than 40% of the shrinkable fibers made by heat-stretching thermoplastic fibers, e.g. acrylonitrile and polypropylene fibers. In order to improve the water resistivity of the paper, various resins may be used, such as urea-formaldehyde resin, melamine resin, epoxy resin, polyethylene-imine resin, dialdehyde-starch resin, etc. To improve the water-repellency of the paper,

a suitable water-repellent agent, such as silicone resin, wax, chromestearate chloride, and the like may be used. The aforesaid treatments with various resins and agents can be done either by adding the resins and agents in the liquid stock, or by impregnating the paper with such resins and agents by means of the spray gun after drying the paper. The patterned paper according to the present invention may be laminated with non-patterned paper by superposing the patterned paper on a wet-web and rolling them together under pressure.

Other objects and a fuller understanding of the present invention may be had by referring to the following description, taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a diagrammatic illustration of a device for producing patterned paper, according to the present invention, shown in a schematic longitudinal section;

FIG. 2 is a schematic perspective view of a dewatering means usable in the device of FIG. 1, shown in an enlarged view; and

FIG. 3 is a schematic bottom view of a nozzle means for producing water jets.

Like parts are shown by like numerals and symbols throughout the drawings.

Referring to FIG. 1, a head box, generally represented by a reference numeral 10, stores liquid stock 12 supplied from a source (not shown). The stock 12 can be prepared by any known method, and it can be any mixture of suitable fibers, including one or more of wooden pulp, cotton fibers, linen fibers, other natural fibers, acryl fibers, polyamide fibers, polyester fibers, polyurethane fibers, and other synthetic fibers. It is possible to add binder fibers in the stock, and polyvinyl alcohol fibers are preferable as such binders. An outlet or nozzle 101 of the head box 10 is gradually sloped downwards, so

that the stock 12 can be disposed on a machining wire cloth 14 at a uniform thickness. The wire cloth 14 is driven by wire rolls 16a, 16b, 16c, and 16d.

As clearly depicted in FIG. 2, the lower edge 102 of the front wall of the head box 10 is bent forward by 40 to 60 degrees with respect to the vertical upper portion of the wall. A threaded bolt 102a is secured to the edge 102, and a lip or slidable plate 104 is mounted on the edge 1102 by fitting the threaded bolt 10211 in a slot (not shown) of the plate 104 and fastening with a nut 103, in an adjustable manner. The thickness of the paper to 'be machined can be adjusted by controlling the spacing between the free end 104a of the lip plate 104 and the endless support or machining wire cloth 14 by sliding the plate 104 on the lower edge 102. It is preferable to mount at least one eye-ring 104b in the proximity of the free end 104a of the plate 104, so that the free end 104a can be resiliently suspended by a flexible wire 1040 extending between the eye ring 104b and a pulley 104d.

The flow of the stock 12 fed into the head box 10 through an inlet opening 105 is controlled by a rectifier roll 106, so as to flow at a controlled rate towards a bottom lip plate 104', which is mounted on the bottom of the head box 10 and directed towards the lower front side of the box. The bottom lip plate 104' is somewhat shorter than the other lip plate 104, and cooperates with the latter to guide the stock onto the machining wire cloth 14.

At least one drainage box 18 is disposed underneath that portion of the machine wire cloth 14 where the stock is delivered from the head box. The upper surface of the drainage box 18 is substantially in contact with the machine wire 14, while the lower end of the box 18 communicates with a draft or suction means 20 through a tube 22.

With the dewatering means of the aforesaid structure, the water in the stock liquor is eliminated very efficiently, up to about of the moisture while the machine wire cloth travels a relatively short distance, e.g. 250 to 500 Areal weight (gr/m?) 19.65

Burst factor 1.577 Percent Elmendorf 111.95

Breading length (km.)

M.C. 1.067 Bulk density 0.2 43

The wet-web thus formed on the wire cloth 14 is fed under a patterning belt 24, which is driven by rolls 26a, 26b, 26c, and 26d, at the same travelling speed with the wire cloth 14. The patterning belt 24 is made of any suitable material such as metal, plastic, or rubber, and having a number of perforations for forming a desired pattern. When the wet-web travels between the belt 24 and the wire cloth 14, pressurized water is uniformly jetted from a plurality of holes of shower pipes 28, through said perforations of the belt 24 onto the wet-web.

In the embodiment illustrated in FIG. 3, the shower pipes 28 are connected to a pair of manifolds 32 through rubber, or other flexible hoses 34, at each end thereof, and the manifolds 32 are in turn connected to a main pipe 30 through a main valve P. Regulating valves P P are provided, one for each connection between the shower pipe and the manifold. The pressure of water to be ejected from a plurality of jet-holes 281 bored on the shower tubes 28 can be regulated by controlling the degree of opening of the valve P and regulating valves P P The details of the water jet means, such as the number and size of shower pipes, the arrangement of such shower pipes, the number and dimension of holes to be bored on the shower pipes, the distance between the shower pipes parallelly arranged, and the pressure of water ejected from the holes can be determined experimentally, depending on the thickness of the wet-web to be treated, the composition of the stock, the feeding rate of the stock, and the like, so that the wet-web may not be eroded by the pressure of the injected water and that the desired perforations or cavities may be effectively formed. In a preferred embodiment of the present invention, there are 3 to 10 shower pipes at intervals between 10 to 100 cm., each having a diameter of 25 to 50 mm. and 200 to 500 jet-hole perimeter of pipe length of 0.5 to 1 mm. dia. to keep the water pressure inside the shower tube at 0.1 to 3 kg./cm.

The pressurized water thus ejected from the belt 24 penetrates through the wet-web while forming holes or recesses corresponding to the perforations of the belt on the wet-web. There are a plurality of suction boxes 34 disposed across that span of the patterning belt 24 where the pressurized water injected, so that the water passes through the wet-web quickly to accelerate the exact transfer of the pattern preformed on the patterning belt 24 onto the wet-web. The section pressure of the suction box 34 is determined depending on the thickness of the wet-web and the rate of pressurized water ejection. When the wetweb is quite thin there is no need for using the suction box 34.

It is preferable to provide a metallic screen 36 of about 10 to 15 mesh between the shower pipes 28 and the patterning belt 24, in order to achieve uniform water pressure distribution over the entire span of the wet-web of the ejected water spray issuing from the pipes 28.

The wet-web thus patterned is then moved from the wire 14 to an endless belt of felt 40 driven by IOlls 38a, 38b, 38c, and 38d. The web then proceeds to a drying section, because its water content is about to 88% when it is moved to the felt 40. For instance, a roll type dryer 42 is used to dry the web. If it is desired to crepe the product, a crepe doctor 44 can be used when the patterned paper thus dried leaves the dryer 42. According to a test carried out, a sample having an areal weight of 30' gr./m. and a softness of 32.5, as determined by the Clark method prior to creping, was converted into a crepe tissue having the softness of 13 3, by treating the former at a crep'ing rate of 20 by using a dryer roll 42 rotating at a surface speed m.. sec. in conjunction with a pope reel roll 46 rotating at a surface speed 80 mm./sec.

If a wet-web is prepared by mixing non-shrinkable fibers with shrinkable fibers, which shrinkable fibers are made of thermoplastic fibers, such as acrylonitrile and polypropylene fibers, by applying heat stretch treatment thereto, such web can be easily converted into soft clothlike paper by heating it to a temperature between 100 and C. When such web is thus heated, the shrink able fibers therein shrink by about 20 to 30%, while the non-shrinkable fibers contained therein substantially do not shrink. The difference in the shrinkage between the shrinkable and non-shrinkable fibers contained in the web results in softening the product. In other words, with such mixed paper stock, the dryer roll or drum 42 works only as a heater, and the crepe doctor 44, as shown in FIG. 1, can be dispensed with, so that the paper dried by the dryer roll 42 is directly wound on the pope reel roll 46.

In order to produce a laminated paper with pattern, a sheet of patterned paper thus dried, through the processes described hereinbefore, is superimposed on a wet-web delivered on the wire 14 from the head box 10, and both the wet-web and the patterned paper laminated thereon are forwarded between the patterning belt 24 and the machine wire 14, to bond them together by pressure without ejecting the pressurized water thereto.

In order to illustrate an embodiment of the present invention in further detail, essential dimensions thereof are described below. It should be noted that the following data are not intended to limit the scope of the invention but to facilitate a better understanding thereof.

(1) Continuous production of patterned paper Composition of stock,

Rayon--5 0% Pulp- 10% Polyvinyl alcohol fibers (binder fibers)10% Concentration of liquid stock-411%. Areal weight20 gr./m. Width of machined paper-1 meter. Travelling speed of machine wire-100 m./ min. Travelling speed of patterning belt100 m./ min. Water pressure of shower-15 atm. Manufacture of laminated paper with pattern Patterned paperaccording to the item 1. Wet-web, stock-400% pulp.

Liquid stock concentration0.1%.

Moisture content of wet-web88%.

The above-mentioned patterned paper and the wetweb, which are laminated to each other, are processes between the machining wire cloth and the patterning belt at a travelling speed of 100 m./min.

Although the present invention has been described with a certain degree of particularity, it is understood that the present disclosure has been made only by way of example and that various modifications in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and the scope of the invention as hereinafter claimed.

What is claimed is:

1. A device for continuously manufacturing patterned paper, said device comprising a running machine wire means, means for distributing liquid stock onto said machine wire means at a uniform thickness, first dewatering means for removing most of the moisture in said liquid stock thus distributed on the machine wire means to form a continuous wet-web, a patterning belt positioned above said machine wire means and means having perforations and being moved in close proximity to and at the same velocity as said running machine wire means, means for ejecting water under pressure through said perforations onto the wet-web, a screening means disposed below said water ejecting means and above a portion of said patterning belt means for spraying water uniformly onto said wet-web, second dewatering means for removing the water ejected through said perforations and through corresponding portions of the Wet-web and said machine wire, and

. means for heating the wet-web to thereby dry said wetweb into said patterned paper.

2. The device for continuously manufacturing patterned paper, as claimed in claim 1, wherein said means for distributing said liquid stock is a head box comprising a hollow body member in which liquid stock is supplied from a source and stored therein, said head box including an outlet portion, a stationary lower lip which extends from said outlet portion and is spaced proximate the machine wire to distribute the liquid stock on the latter, and an upper lip plate including a first lip plate having one end which is secured to the wall of said hollow body and an opposite end which is slanted downwardly toward the machine wire and a second lip plate having one end secured to said first lip plate and a further free end adjustably suspended so as to leave a controllable space, corresponding to the desired thickness of the wetweb to be formed, between the free end of said second lip plate and the machine wire surface, and wherein said first dewatering means includes a main suction box spaced just UNITED STATES PATENTS 3,350,260 10/ 1967 Johnson 162-299X 3,471,368 10/1969 Reitzel 162336X 1,957,913 5/1934 Smith 162111X 2,862,251 12/ 1958 Kalwaites 162114X 3,014,832 12/1961 Donnelly 162-111 3,042,576 7/1962 Harmon et al 1621 14 3,129,466 4/1964 LHommedieu 162-1 14X OTHER REFERENCES Sushereba, J. A.: Broad Selection of HeadboxesConsiderations for Fine Papers, Paper Trade Journal, Aug. 3, 1964, pp. 2225.

HOWARD R. CAINE, Primary Examiner A. DANDREA, JR., Assistant Examiner US. Cl. X.R.

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