US3457898A

US3457898A - Apparatus for treating a continuous web or film of material with a liquid

Info

Publication number: US3457898A
Application number: US648152A
Authority: US
Inventors: Ulrich Frauchiger; Joseph Becheiraz
Original assignee: Ciba AG
Current assignee: BASF Schweiz AG
Priority date: 1966-06-23
Filing date: 1967-06-22
Publication date: 1969-07-29
Anticipated expiration: 1986-07-29
Also published as: AT295992B; NL6708728A; BE700360A; CH458265A; DE1610925A1; FR1548316A; GB1183517A; SE305398B; CH476525A

Description

y 196$ u. FRAUCHIGER ETAL 3,457,898

APPARATUS FOR TREATING A CONTINUOUS WEB OR FILM 0F MATERIAL WITH A LIQUID Filed June 22, 1967 4 Sheets-Sheet 1 In'n S m TmM WWR I E VWH C NA, IRE FB H R 3 L0 UJ ATTORNEYS y 29, 1969 u. FRAUCHIGER ETAL 3,457,898

APPARATUS FOR TREATING A CONTINUOUS WEB 0R FILM 0F v MATERIAL WITH A LIQUID Filed June 22, 1967 4 Sheets-Sheet 2 F IG. 3

INVENTORS ULRICH FR9UC HlGER JOSEPH BECHEIRAZ ATTORNEYS.

3,457,898 APPARATUS FOR TREATING A coNTINuoUs WEB 0R FILM OF Filed June 22, 1967 y 29, 1969 u. FRAUCHIGER ETAL MATERIAL WITH A LIQUID 4 Sheets-Sheet I5 INVENTORS ULRICH FR AUCHIGER JOSEPH BE CHEIRAZ ATTORNEYS July 29, 1969 u. FRAUCHIGER ETAL 3,457,898

APPARATUS FOR TREATING A CONTINUOUS WEB OR FILM OF MATERIAL WITH A LIQUID Filed June 22, 1967 4 Sheets-Sheet 4 u INVENTORS H FRQUCHIGEK JOSEPH BECHEIRAZ ATTORNEYS United States Patent M 3 457 898 APPARATUS FOR TIQEATING A CONTINUOUS WEB 0R FILM 0F MATERIAL WITH A LIQUID Ulrich Frauchiger, Winterthur, and Joseph Bcheiraz,

US. Cl. 118419 16 Claims ABSTRACT OF THE DISCLOSURE Apparatus for treating webs or films of material, such, as paper, fabric or photographic film comprises a distributor within a tank. The material to be treated is led past the distributor from which treating liquid issues through slit-like nozzles in turbulent motion. The distributor may comprise a bank of orificed tubes each having at least two, and preferably three, elongated spaced strip-like baffle plates therebelow, so arranged that the edges of the bafiie plates define between them the nozzles, or may comprise a pressure-tight vessel having channel means in its side, the mouths of the channel means defining the nozzles. Means are provided for feeding the liquid to the distributor and for withdrawing it form the tank. The material may pass down the tank and back past both sides of the distributor and be led at its lower end over a freely rotatable return roller. lets of treating liquid may be directed into the gap between the material and the roller to cushion the material.

This invention relates to apparatus for treating continuous webs or films of material, such as paper or fabric webs, or photographic films, with a liquid.

Various methods and arrangements have already been proposed for treating sheet or band material, such as paper and fabric webs, photographic film and the like, with liquids that are in motion. For example, in one such arrangement the continuous webs are-pulled through treating baths by mechanical conveying means and, ac-

cording to the intensity of interaction between the liquid and the surface of the web that is desired, more or less intense motion is imparted to the treating liquid. For thus imparting motion to the liquid in a bath in relation to the surface of a material that is to be treated thereby, devices such as agitators, vibrators, ultarsonic oscillators, nozzles and the like have already been used. Such nozzles are arranged to discharge a continuous or pulsed stream of gas into the liquid and the bubbles which then rise in the liquid are intended to generate local turbulent motion. In apparatus comprising means for continuously renewing or circulating the treating liquid it has also been proposed to contrive the circulating means in such a way that a large degree of agitation is simultaneously produced in the bath.

However, all these prior arrangements have the defect that considerable power must be expended to produce a sufficiently high degree of relative motion between the liquid and the treated surface and that it is also impossible to achieve a completely uniform distribution of the volume of liquid contacting the surface as well as a uniform distribution of liquid velocities.

It is therefore one object of the present invention to provide apparatus in which a relatively high velocity gradient can be generated between the liquid and the treated surface. Another object of the invention is to reduce the required power consumption to a minimum.

3,457,898 Patented July 29, 1969 Yet another object of the invention is to ensure that the velocity distribution over large surface areas is uniform. This is a matter of major importance in cases in which the relative velocities between the liquid and the treated surface and the period of contact directly govern the intensity of the effect that is desired, as is the case for instance in dyeing processes or in the processing of an exposed photographic film.

According to the present invention there is provided apparatus for treating a continuous web or film of material with a liquid, comprising a tank for receiving said liquid, means for admitting liquid into the tank, means determined path, the arrangement being such that, when the apparatus is in operation, the liquid issues from said nozzles in turbulent flow and is directed on to the traveling material.

Preferably the distributor means comprises a plurality of orificed distributor tubes placed with their axes parallel and alongside the predetermined path of travel of the material, and the slit-like nozzles are preferably constituted by the edges of a plurality of superposed elongated strip-like plates disposed in parallel the one behind the other, each plate, with the exception of the last plate remote from the orifices in its associated distributor tube, being provided with at least one opening in the path of the jets of liquid issuing from the orifices, the cross-sections of said openings extending at least partly over solid surface parts of the following plate in the path of the jets.

In order to enable the invention to be more readily understood, reference will now be made to the accompanying drawings, which illustrate diagrammatically and by way of example some embodiments thereof, and in which:

FIG. 1 is an elevational section of a tank equipped with a distributor, the section being taken in a plane parallel to a bank of tubes which together 'formjthe distributor,

FIG. 2 is a section taken on the line IIII in FIG. 1,

FIG. 3 is a section of a detail in FIG. 2, drawn to a larger scale,

FIG. 4 is a part sectional perspective view ofanother distributor, and

FIG. 5 is a section taken on the line V-V in FIG.

Referring now to FIGS. 1 to 3 of the drawings, there is shown a distributor, generally indicated by 1, which is vertically built into a tank 2. The distributor comprises

tubes

3a, 3b, 3c, 3d and 32 forming a bank of axially parallel coplanar tubes parallel to the path of travel of a material to be treated as indicated in FIG. 2 by a thin line 4. Each tube is formed with a row of orifices 5 situated on at least one line of intersection of the tube with the plane containing the axes of the tubes in the-bank.

Each row of orifices is faced by baflles or flow-deflecting elements which in the illustrated embodiment have the form of three parallel relatively spaced elongated strip like

bafile plates

6, 7 and 8 facing the row of orifices and placed the one behind the other. The two

plates

6 and 7 nearest the row of orifices are each formed with a

slot

9 and 10 respectively, the longitudinal centre lines of the slots being likewise contained in the plane containing the tube axes and the rows of orifices 5, but the plate 8 furthest away from the orifices is not formed with such a slot. The size of the slots, particularly their width, de-

creases from plate to plate with increasing distance of the plates from the orificed tube which they face. In a preferred embodiment of this arrangement the

plates

6, 7 and 8 are transversely arched with their concavities facing the associated orificed tube, as is clearly shown in FIG. 3 which also shows the general arrangement and the relative sizes of the

slots

9 and 10.

It should also be understood from FIGS. 1 and 2, that the path of travel 4 of the treated material extends along both sides of the bank of distributor tubes, the material being taken over a return roller 11.

Below the bottom distributor tube 3e of the bank, i.e. between this tube and the return roller 11 for the travelling material 4 is a suction tube 12 which extends parallel to the distributor tubes 3a to Sc, and which is formed at its periphery with orifices having a total open cross-section at least equal to the total open cross- 20B. Each of these two chambers has a separate consection of the orifices in all the distributor tubes in the bank. Preferably, and as illustrated, the orifices in the suction tube align along the bottom generator of the tube.

The distributor 1, the baflle or

deflector plates

6, 7, and 8, the suction tube 12 and preferably the roller 11 for the treated material form a structural entity built into the tank as a unit.

In the operation of the apparatus just described, the tank 2 is filled with the treating liquid and the material to be treated is fed along the path 4 and around the return roller 11 by conventional means not shown in the drawings. The treating liquid is admitted to the tanks via a manifold 33 which communicates with one end of each of the tubes 3a-3e which are all closed at their other ends. The liquid issues as a series of jets from the orifices 5 and some of its strikes the baffle plate 6 causing turbulent motion of the surrounding liquid which flows over the edge of the plate 6 to be directed onto the travelling material. Some of the jet of liquid passes through the aperture 9 to strike the baflle plate 7 while some of the jet passes through the aperture 10 to strike the plate 8. The

liquid striking the

plates

7 and 8 causes turbulent motion of the surrounding liquid so that the liquid, in turbulent motion issues from the slit-like nozzles defined by the edges of the

plates

6 and 7, and 7 and 8 respectively to be directed onto the travelling material. The liquid is withdrawn from the tank by the suction pipe 12.

The distributor illustrated in FIGS. 4 and 5 comprises a pressure-tight vessel which has two

side walls

21 and 22 which are parallel to the planes in which a material to be treated travels. Each of these walls is formed with open channels 23 which extend crosswise of the

path

4a, 4b of the travelling material. A wall portion 23a of these channels projecting substantially perpendicularly inwards from the

walls

21 and 22 of the tank is formed with a row of orifices 24. Inside each channel a narrow strip-shaped part 23b of the internal channel wall which likewise projects substantially perpendicularly from the

distributor walls

21 and 22 faces the orifices. Each channel is completely open towards the path of the treated material. This is an important feature because the presence of obstructions of any kind might operate to reduce the turbulence generated inside the channels.

A returnroller 11 and one chain wheel 25 is all that can be seen in FIG. 4 of means for conveying the material to be treated. These elements are directly mounted on the pressure-tight vessel and thus together therewith form a structural unit which can be built into a tank in exactly the same way as the distributor unit shown in FIGS. 1 and 2. A second chain wheel (not shown) is mounted at the front end of the return roller 11 in FIG. 4. However,

the two chain wheels and the return roller are not coupled but individually rotatable. The chain wheels deflect a chain (not shown) for entraining the treated web of material.

The pressure-tight vessel illustrated in FIG. 4 is horizontally divided into two separate chambers 20A and nection for the supply of a treating liquid under pressure. In the illustrated embodiment the connection into the upper chamber 20A is indicated at 26, whereas that for the lower chamber is a pipe 27 which extends downwards through the upper chamber into the lower chamber. The top of the pressure-tight vessel is further provided with a cover 28 which tightly closes an inspection and cleaning window.

As shown in FIG. 5, the pressure-tight vessel according to FIG. 4 is intended to be built into a tank 2 (similar to the tank 2 shown in FIG. 2) which is fitted with a separate connection for the extraction of the liquid, or with an overflow. Alternatively, the pressure-tight vessel itself might be further subdivided to form at least one suction chamber.

Closely above the return roller 11 the bottom chamber 20B which is shown in cross-section in FIG. 5 is formed with a semi-cylindrical convex bulge 29 extending parallel with and lengthwise of the return roller. This convex bulge contains a row of orifices 30 along the length of the roller 11. In relation to the roller 11 these orifices 30 are so disposed that the jets issuing therefrom are directed into the wedge-shaped gap between the roller surface and the surface of the material 4a running onto the roller. These jets likewise consist of the treating liquid which can be introduced into chamber 20B through the pipe 27 at a pressure above that of the liquid entering the chamber 20A through the pipe 26. The jets impinge on the roller surface at an acute angle, nearly tangentially, and they therefore operate both to drive the freely rotatable roller in the direction of travel and to create between the roller surface and the treated web of material a cushion of liquid which eliminates or at least reduces the resistance generated by the deflection of the material, prevents the material from being damaged by contact with the return roller and increases the effect of the treatment. These elfects can be further assisted by a deflector strip 31.

v The distance of the jet orifices 30 from the surface of the roller 11 is only a fraction of the roller diameter, preferably said distance being between 1 and 10 mm.

The present method of guiding the treated material over a freely rotatable roller which is jet driven, and upon which a liquid cushion is formed, may be used with advantage wherever it is desired to deflect continuous webs or films of material in a liquid.

. The directions of pressure and suction in the pipe means and the directions of the jets are indicated in the drawings by arrows. Arrows also show the directions of travel of the treated material and the direction of rotation of the roller.

What is claimed is:

1. Apparatus for treating a continuous web or film of material with a liquid, comprising a tank for receiving said liquid, means for admitting liquid into the tank, means for withdrawing the liquid from the tank, means for conveying the material to be treated through the tank along a predetermined path, distributor means including orifices for said liquid positioned within the tank adjacent to said predetermined path and connected to the means for admitting liquid into the tank, and baffle means arranged facing the orifices of said distributor means and disposed at a steep angle to said predetermined path, said orifices are disposed for directing jets at a steep angle onto said baffle means, so that, when the apparatus is in operation, the liquid issues from said baflle means in turbulent flow and is directed onto the travelling material.

2. Apparatus as claimed in claim 1 wherein the angle between the jets and the baffle means is about 3. Apparatus for treating a continuous web or film of material with a liquid, comprising a tank for receiving said liquid, means for admitting liquid into the tank, means for wthdrawing the liquid from the tank, means for conveying the material to be treated through the tank along a predetermined path, distributor means including orifices for said liquid positioned within the tank adjacent to said predetermined path and connected to the means for admitting liquid into the tank, and baffle means ar ranged facing the orifices of said distributor means and disposed at a steep angle to said predetermined path, said orifices are disposed for directing jets at a steep angle onto said baffle means, said distributor means comprises a plurality of distributor tubes placed with their axes parallel and forming a bank alongside said predetermined path, portions of each tube defining orifices which are arranged in a row, said baffle means comprises at least two superimposed elongated strip-like baffle plates arranged below said orifices each baflle plate being apertured except for the lowermost bafile plate, the arrangement of the baffle plates being such that the spaces between the edges of the baffle plates define slit-like nozzles, at least some of the treating liquid being intended to pass from said orifices through the aperture in each plate and to issue in turbulent flow from the slit-like nozzles defined by the edges of the baffle plates.

4. An apparatus as claimed in claim 3 wherein there are at least three such bafile plates, the aperture in any bafile plate being wider than that in the baffle plate immediately below it.

5. Apparatus as claimed in claim 4 wherein the tubes and baffie plates are arranged in a vertical bank.

6. Apparatus as claimed in claim 5, wherein the means for withdrawing the liquid from the tank includes an orificed suction tube extending parallel to and below the distributor tubes.

7. Apparatus as claimed in claim 6 wherein the distributor means, the suction tube and the means for conveying the material through the tank are combined in a structural assembly vertically mounted as a unit inside the tank.

8. Apparatus as claimed in claim 4 wherein the sides of the bafile plates facing the associated distributor tube are concavely arched.

9. Apparatus for treating a continuous web or film of material with a liquid, comprising a tank for receiving said liquid, means for admitting liquid into the tank, means for withdrawing the liquid from the tank, means for conveying the material to be treated through the tank along a predetermined path, distributor means for said liquid positioned within the tank adjacent to said predetermined path and connected to the means for admitting liquid into the tank, said distributor means comprises a pressure-tight vessel, at least one side wall of said vessel lying substantially parallel to said predetermined path, orificed channel means let into each side wall of the vessel extending in a direction transverse to the intended direction of travel of the material, the orifices in said channel means communicating with the interior of the vessel and are disposed for directing jets at a steep angle onto an area of the channel wall which is disposed at a steep angle to said predetermined path, so that, when the apparatus is in operation, the liquid issues from the mouths of the channel means in turbulent flow and is directed onto the travelling material.

10. Apparatus as claimed in claim 9, wherein the angle between the jets and said area of the channel wall is approximately 90.

11. Apparatus as claimed in claim 9, wherein the area of the channel wall which faces said row of orifices is concavely formed.

12. Apparatus for treating a continuous web or film of material with a liquid, comprising a tank for receiving said liquid, means for admitting liquid into the tank,

means for wthdrawing the liquid from the tank, means for conveying the material to be treated through the tank along a predetermined path, distributor means for said liquid positioned within the tank adjacent to said predetermined path and connected to the means for admitting liquid into the tank, and bafile means arranged facing the orifices of said distributor means and disposed at a steep angle to said predetermined path, said orifices are disposed for directing jets at a steep angle onto said baffle means, said predetermined path extends from the top of the tank to the bottom and back to the top, the return of the travelling material inside the tank being effected over a freely rotatable roller along the length of which further jet orifices are disposed for directing jets into the wedge-shaped gap between the surface of the roller and the surface of the material running over the roller.

13. Apparatus as claimed in claim 12, wherein the distance of said further jet orifices from the surface of said roller is only a fraction of the roller diameter.

14. Apparatus as claimed in claim 13, wherein said distance is between 1 and 10 mm.

15. Apparatus as claimed in claim 12, wherein said further jet orifices are formed in a quasi-tubular distributor extending parallel to the return roller, said distributor being fitted with a longitudinal deflector projecting substantially tangentially towards the roller surface in such manner that the last mentioned jet orifices are contained within the gap defined between said deflector and the roller surface.

16. Apparatus for treating a continuous web or film of material with a liquid, comprising a tank for receiving said liquid, means for admitting liquid into the tank, means for wthdrawing the liquid from the tank, means for conveying the material to be treated through the tank along a predetermined path, distributor means for said liquid positioned within the tank adjacent to said predetermined path and connected to the means for admitting liquid into the tank, said distributor means comprises a pressure-tight vessel, at least one side wall of said vessel lying substantially parallel to said predetermined path, orificed channel means let into each side wall of the vessel extending in a direction transverse to the intended direction of travel of the material, the orifices in said channel means communicating with the interior of the vessel and are disposed for directing jets at a steep angle onto an area of the channel wall which is disposed at a steep angle to said predetermined path, said predetermined path extends from the top of the tank to the bottom and back to the top, the return of the travelling material inside the tank being effected over a freely rotatable roller along the length of which further jet orifices are disposed for directing jets into the wedge-shaped gap between the surface of the roller and the surface of the material running over the roller.

References Cited UNITED STATES PATENTS 1,579,003 3/1926 Koch 118-429 X 3,192,845 7/1965 Schmidt 89 3,310,062 3/1967 Little 6862 X 3,344,729 10/ 1967 Kitrosser 95-89 WALTER A. SCHEEL, Primary Examiner JOHN P. MCINTOSH, Assistant Examiner U.S. Cl. X.R. 6862; 118429