US 2059881 A
Description (OCR text may contain errors)
Nov. 3, 1936. G. 'r. LANE 2,059,881
APPARATUS FOR SIZING PHOTOGRAPHIC PAPER Original Filed March 12, 1935 2 Sheets-Sheet l INVENTOR. Gerould T. Lane ORNFYS NOV. 3, 1936. LANE 2,059,881
APPARATUS FOR SIZING PHOTOGRAPHIC PAPER Original Filed March 12, 1935 2 Sheets-Sheet 2 FUSE, 38 ,5 O
. INVENTOR. Gerould T. Lane BY m/M.
Patented Nov. 3, 1936 v UNITED STATES PATENT OFFICE Gerould T. Lane, Rochester, N. Y., assignor, by
mesne assignments, to Eastman Kodak Company, Jersey City, N. J., a corporation of New Jersey Original application March 12, 1935, Serial No. 10,635. Divided and this application March 7,
- 1936, Serial No. 67,701
This invention relates to paper making and particularly to an apparatus for sizing paper. One object of my invention is to provide a machine in which paper is passed against a counter-current fiow of gas before entering the sizing bath. Another object of my invention is to provide an apparatus for quickly and completely treating a sheet of paper with live steam just before it passes into a sizing bath. Another object of my invention is to provide a steam chest having tapered plates spaced from the sheet, past which steam may pass to remove air from the interstices of the sheet before it passes into the fixing bath. Still another object of my invention is to provide a steam chest having two relatively separable sections, one of which can be moved in relation to the other for initially threading paper through the steam chest. Still another object of my invention is to provide a' steam chest with a Venturi tube through which steam may pass, and other objects will appear from the following specification, the novel features being particularly pointed out in the claims at the end thereof.
This application is a division of my co-pending application for Method of and apparatus for sizing photographic 'paper, filed March 12, 1935, Serial No; 10,635.
In the past, sizing has been one of the most difilcult steps to accomplish properly in paper making. It is desirable to use a concentrated size so that a single treatment will size the paper with size of the desired strength, but if concentrated size is used, only the surface is treated and but little size penetrates to the interior of the sheet. Since thefibers are not cemented well together, the resulting sheet is not strong.
On the other hand, if thin or dilute size is used, the sheet may be wetted quite fully, but the dilution is such that the fibers, while wetted, are not properly cemented together because so little size gets into the sheet. Here too, the sheet is not nearly as strong as it might be.
- Consequently, sizing has generally been a compromise in which paper strength has been definitely sacrificed. If proper'strength size is made to penetrate throughout a. sheet or web of paper, so that all the fibers are cemented together, a paper sheet can be made many times stronger than the present practice with fibers of the same length and character.
It is to overcome these sizing difiiculties, which are well-known in the art, and are particularly well-known to makers of fine, high strength papers which must be used in various arts requiring treatments which dampen or wet the paper, such as for photography, lithography, art work, etc., that the present invention was made. I have been able to size with a concentrated solution (say 6 per cent) and to cause the size to penetrate fully into the body of the sheet, and to actually over-size paper by the method and apparatus which will now be described.
Coming now to the drawings in which like reference characters denote like parts throughout:
Fig. 1 is a side elevation partially in section, showing an apparatus for sizing paper constructed in accordance with and embodying'a preferred form of my invention.
Fig. 2 is an enlarged fragmentary sectional view of the apparatus shown in Fig. 1.
Fig. 3 is an enlarged cross-section of the steam chest used with a preferred form of .my sizing apparatus.
Fig. 4 is a fragmentary detail of a secondembodiment of my invention showing the means for adjusting the width of the paper entrance to the steam chest. I
Fig.25 is an enlarged sectional view taken on line 5-5 of Fig. 4.
In accordance with the drawings wherein a pre- -ferred form of my invention is shown, I may provide an apparatus for sizing paper, as shown in Fig. 1, wherein there is a tank I which is adapted to hold sizing solution 2 which may be brought up to a predetermined level 3. At one end of the tank I, there is mounted a steam chest designated broadly as 4 in which there is an aspirator for treating the paper, this aspirator being operated by means of steam which may be passed to the steam chest 4 through the pipes 5 and 6, the amount of steam being controllable by means of the valves! and 8.
A bracket 9 on top of the steam chest supports a roller I0 over which a paper web P may be drawn directly from the drying rolls II.
Beneath the steam chest a guide roller I2 is mounted, and the paper web P is drawn beneath this guide roller through the sizing solution around a second guide roller [3 mounted in the opposite end of'the sizing tank I. Above roller I3, thereis mounted a pair of squeezing rollers arranged to permit the paper web P to move continuously at a relatively high speed. In fact I have found that the sizing operation is no longer a limiting factor in the speed of operation of the machine and that I can completely size paper as fast as the web can be formed on the making wire.
As indicated in Figures 2 and. 3, the steam chest 4 preferably consists of two sections I! and I8 which are hinged together at 19, so that one section can swing relative to the other. I provide bolts or screws 20 at the end opposite to the hinge l9 these fasteners passing through the cooperating flanges 2| and 22, so that the covering of suitable insulation material, such as' asbestos cement, or the like, as indicated at Fig. 3 at 64, since this is useful in keeping the interior of the steam chest at a constant temperature and preventing too great a loss of heat. I also prefer to provide drains 32' and 33' in each bottom section to carry off any water which may form if steam condenses.
Referring to Fig. 3, the steam chest 4 is provided with a pair of walls 24 and 25 which are fastened to flanges 26 and 2! at the upper walls 28 and 29 of the steam chest, the lower edges 30 and 3| of these plates being spaced some distance above the bottom'walls 32 and '33. These converging walls form an aspirator when steam passes upwardly between these walls about both sides of the paper web P as it is moving downwardly between the walls. The countercurrent flow of steam either prevents the air inside of the paper web from entering the steam chest 4, or sucks the air out of the sheet.
The paper entrance designated broadly as 35 consists of a slot between two L-shapecl members 36 and 31 which may be adjusted relative to each other to vary the space between them. This may be'done by means of knurled knobs 38. The adjustment of these two members controls, to a large extent, the aspirating effect which is obtained by permitting steam to enter through the pipes 5 and 6, altho the adjustment of valves 1 and 8 likewise controls the aspirating of the paper web.
In order to prevent the steam from rushing in through the pipes 5 and 6 and displacing walls 24 and 25, and in order to make the steam circulate rapidly and satisfactorily, I prefer to provide similar brackets 40 on each of the side walls 4| of the steam chamber and tovprovide the brackets 40 with downwardly extending baffle plates 42. As will be seen by the arrows, these plates deflect steam entering through these pipes so that it will be distributed uniformly without undue pressure on any part of the steam chest.
While I circulate steam in the steam chest quite freely, and at a 'high velocity, I prefer to use it in such a way that no appreciable pressure is built up in the steam chamber and so that the steam entering the pipes 5 and 6 will pass up through the aspirator and out of the paper entrance. Thus the pressure is insufficient to cause the steam to pass out through the paper exit beneath the surface of the size. I have found that steam from a 20 lb. line passing into the steam chest from a inch pipe produces the desired results although this is only by way of example and does not limit my invention.
The paper exit is preferably formed by the bottom walls 32 and 33 of the hinged sections, and I likewise prefer to provide two similar upstanding flanges 44 on the two sections which are spaced apart a sufiicient distance to allow the paper to pass freely down between these members. It will be noted that the bottom walls of the steam chamber are substantially at, or below the level 3 of the size 2 in the tank I and that the paper web passes directly from the paper exit into the size without being allowed to come in contact with air. The reason for this is as follows:
As the paper comes in overthe guide roller l0, while it may have been partially or entirely dried by the'drying rolls II, nevertheless, considerable air and/or moisture will remain between the fibers of the sheet. This prevents successful sizing. As the paper passes down through the paper entrance formed by the walls 36 and 31, the steam is passing out from this paper entrance, as indicated in Fig. 1, and car ries out with it all the air which was included between theflbers of the sheet coming from the drying rolls II.
This takes place very rapidly. It is possible to operate my sizing machine with the paper moving at relatively high speeds, such as 120 feet per minute." In fact'my improved method of sizing permits machines to be run at any commercial speeds. Thus, the actual time of the steam treatment is exceedingly brief because I have found that a steam treatment tank, approximately twelve inches long, will be entirely satisfactory. If the paper web should be traveling 120 ft. per minute it would therefore be steam treated in about a half of a second. Of course, these figures are given by way of illustration only, and the size of the steam chest may be varied to suit the particular conditions under which the paper is made. The necessary step is to treat the entire sheet with a blast of steam. 7
As the paper passes down between the Venturi plates 24 and 25, the air is entirely removed from the interior of the paper web. In fact, I believe the blast of steam prevents any air being carried into the steam chest 4. The web is then passed directly beneath the surface 3 of the size 2. The size is, of course, cooler than the steam, and, any steam in the sheet will be condensed, but one part in fourteen hundred of water resulting from such condensation is immaterial. No air is permitted to contact with the paper web after it passes into the steam chest and before it enters the sizing solution. Atmospheric pressure or the pressure on the sizing solution immediately forces the size thoroughly into and through the sheet and completely sizes the paper. In fact, I have found that I' can place so much sizing in a paper sheet that the resulting paper is unsatisfactory. This, however, can be very easily prevented by controlling the amount of steam through the valves I and 8, and/or controlling the width of the paper entrance lips 36 and 31. The less the sizing which is required, the less steam which needs to be admitted to the steam chest 4. The sizing, of course, can also be controlled by the viscosity of the sizing bath.
One of the features of my present invention is that my method permits the use of a sizing bath of high viscosity and at the same time provides a means for causing such a sizing bath to penetrate into the paper. Such a size may be a an improved product, and while it may not be t 6 per cent solution. A 2 percent solution may be considered a normal one. Since air has been entirely removed from the paper web, the sizing bath is forced into the sheet, even though it is considerably more viscous than the bath normally used.
In Fig. 4 I have shown a modified form of adjusting mechanism for the lips. 36 and 31 of the paper entrance plates. As indicated in Figs. 4 and 5, the rails 50 and 5| are provided with openings 52 and 53 in which cams 54 and 55 rest, these cams being movable about the shafts 56 and 51 by means of the knurled heads 58 and 59. In this modification of my invention, both rails are made adjustable to and from each other, whereas in the form shown in Fig. 3, only one rail is made adjustable to and from the other, which may be fixedly mounted.
It is immaterial just how this adjustment is made, the adjustment being primarilyv necessary in initially securing the proper amount of steaming of' the sheet. For instance, it is possible to cause more or lessaspirating effect on the sheet by regulating the width of the paper entrance to the steam chamber. It is also "possible to vary the effect of the steaming by altering the amount of steam through an adjustment of the valves 1 and 8, and the'viscosity of the size can also be used to control the amount of sizing.
The method of treating a wet or dry strip of paper by means of a short contact with rapidly moving steam and passing it directly -through a sizing bath without permitting air to come in contact with the sheet has produced clear as to exactly what occurs in this steam treatment-that is, as to whether the air in the sheet is not permitted to enter the steam chamber at all or whether the air is sucked or drawn out by the steam as it passes in a countercurrent flow over the sheet, it is not important and I do not wish to confine myself to any particular theory of operation of my method and machine for sizing paper.
It is, however, quite clear'that a very short steam treatment of the paper web before plunging it into the sizing solution enables the web to take up a much greater proportion of size than heretofore, and enables the sizing solution to be much more viscous than the normal sizing solutions. In addition, by steaming the paper; as above described, the machine may be run at a relatively high speed without in any way impairing the sizing operation. I have found paper made in known machines can be increased in strength about fifty per cent (Mullen test) the sole difference in the two papers being the use of my improved method of sizing, and I have found that the fold'test (Schopper test) indicates a strength increase of approximately ten times. The figures vary somewhat with the stock used, but illustrate the results which can be obtained by utilizing my improved method and apparatus for sizing.
Moreover, I have found that paper which has been insufiiciently sized can be re-sized by rerunning through a steam sizing machine, and the strength of the paper can be greatly increased by the additional size which can be placed in the web. Thus my method may be carried out as a separate operation entirely successfully with previously sized or unsized paper, although it is more economical to carry out my method as a step in a complete paper making machine. I
While I have ,shown form and on an exaggerated scale a preferred embodiment of a machine constructed in accordance with my invention, it is obvious that a. great many. variations can be made from the structure shown and described, and I contemplate as included in the scope of my invention all such forms of machines, and methods as may come within the terms of the appended claims.
Having thus described my invention, what I claim'as new and desire to be secured by Letters Patent of theUnited Statesis:
1. An apparatus for sizing paper comprising, in combination, a tank adapted to contain size to a predetermined level, and a paper passageway leading to the sizing bath, side and end walls constituting a passageway for paper and shaped to form an aspirator, means for admitting steam on both sides of the paper path through walls of the aspirator, and steam baffies inside of the aspirator to deflect the flow of steam therethrough.
2. An apparatus for sizing paper comprising, in combination, a tank adapted to contain size to a predetermined level, a passageway through which paper may be conducted below. the level of the size comprising a steam chest having a paper entrance above the level of the size, and means for introducing steam to the steam chest whereby it may flow through the chest and out from the paper entrance.
3. An apparatus for sizing paper comprising, in combination, a tank adapted to contain size to a predetermined level, a passageway through which paper may be conducted below the level of the size comprising a steam chest having a paper entrance above the level of the size, and means for introducing steam to the steam chest whereby it may flow through the chest and out .from the paper entrance, said chest being divided into tworelatively movable sections to facilitate threading paper through the machine.
4. An apparatus for sizing paper comprising, in combination, a tank adapted to contain size to a predetermined level, a passageway through which paper may be conducted below the level of the size comprising a steam chest having a paper entrance above the level of the size, and converging walls inside or the chest leading toward the paper. entrance.
in somewhat simplified- 5. An apparatus for sizing paper comprising,
in combination, a tank adapted to contain size to a predetermined level, a passageway through which paper may be conducted below the level of the size comprising a steam chest having a paper entrance above the level of the 'size, and
converging wallsinside of the chest leading toward the paper entrance, said walls terminating above the level of the size.
6. An apparatus for sizing paper comprising, in combination, a tank adapted to contain size .to a predetermined level, a passageway through which paper may be conducted below the level of the size comprising a steam chest having a paper entrance above the level of the size, and. converging walls inside of the chest leading toward the paper entrance, means for admitting steam to said chest behind said converging walls, and means for controlling the width. of the paper entrance. v
7. An apparatus for sizing paper comprising, in combination, a tank adapted to contain size to a predetermined level, a passageway through which paper may be conducted below the level of the size comprising a steamchest having a paper entrance above the level of the size, and a paper exit below the level of the size, whereby paper passing through the steam chest may pass directly beneath the surface of the size, said paper entrance comprising a pair of parallel lips at least one of which is movably mounted with respect to the other.
8. An-apparatus for sizing paper comprising, in combination, a tank adapted to contain .size to a predetermined level, a passageway through which paper may be conducted below the level of the size comprising a steam chest having a paper entrance above the level of the size, and a paper exit below the level of the size, a pair of walls mounted inside of the steam chest converging toward the paper entrance and spaced from the bottom of the steam chest, pipes for introducing steam behind said walls whereby steam entering the chest will be circulated before striking the paper, said steam being adapted to pass from the steam chest through the paper entrance thereto.
9. A paper making machine including a substantially closed steam chamber through which sheet material may be drawn, a paper inlet and a paper exit in walls of the chamber, means for introducing or threading a sheet of paper through the chamber, an impregnating bath mounted beneath the steam chamber, the paper exit of the steam chamber lying beneath the surface 01 the impregnation fluid in the impregnation bath.
10. An apparatus for sizing a continuously moving paper web including a sizing bath, and means for removing air from the paper web before it enters the sizing bath comprising a steam chest including symmetrical, relatively movable sections, walls inside of the steam chest sections forming a steam and paper passageway, each section including one edge of a paper web entrance and exit to facilitate threading paper 7 therethrough.
11. An apparatus for sizing a continuously moving paper web which includes a pair of spaced plates lying close to but out of contact with a paper web and having a restricted paper entrance through which paper may pass without contacting'with the paper entrance, means for introducing live steam between the plates and about the paper web to flow from between the plates out of the paper entrance.
' GEROULD T. LANE.