US2078272A - Apparatus for manufacturing saturated sheeted fibrous structures - Google Patents

Description

APPARATUS FOR MANUFACTURING SATURATED SHEETED FIBROUS STRUCTURES Original Filed Deo. 27, 1952 Cfu Patented Apr. 27, 1937 UNITED STATES PATENT OFFICE APPARATUS FOR MANUFACTURING SATU- RATED SHEETED FIBROUS STRUCTURES Izador J. Novak, Bridgeport, Conn., assignor to Raybestos-Manhattan, Inc., Passaic, N. J., a corporation of New Jersey 9 Claims.

This application is a division of my application Serial No. 648,921, filed December 27, 1932 issued as United States Patent No. 1,966,458, dated July 17, 1934.

This invention relates to an apparatus for producing an improved saturated sheeted fiber, and is especially directed to an improvement in apparatus for introducing binder, sizing, or other modifying materials into paper and fiber board.

It is well known in the paper-making art to immerse or coat a previously formed and partially or completely dried paper in or with various binding materials such as casein solution, glue solution, rubber latex, sodium silicate solution,

glue-glycerine solution, rosin size, and other binders or sizing materials for the purpose of conferring upon the paper or fiber board the qualities produced by the action of those binding or sizing materials when dried on the brous structure of the paper.

It is well known, however, and thoroughly appreciated by the paper industry, by the use of the term top sizing, that impregnation is quite imperfect in the use of many of these materials, especially those of a viscous or colloidal nature, and a thin layer near the surface is frequently the only portion of the thickness of the she-et affected by the binder. In many cases, this is quite satisfactory and is desirable, but in others, where a thorough impregnation would produce a tougher or more flexible product, the limitations of this method are appreciated. The usual term for the saturation of dry paper with a binder additional to the sizing contained in the dry paper i is tub sizing. Many attempts have been made to overcome the limitation of incomplete saturation.

It has been found, for example, that by using a loosely felted or porous paper of a low caliper, a substantially thorough saturation may be obtained, but inasmuch as one of the requisites for better grades of paper is a smooth, tight, dense structure, the selection of such a porous paper as a base for saturation is not always desirable.

Another type of apparatus provides for a rest or ageing period between the saturation and the drying to improve uniformity of saturation, or the equivalent of passing the impregnated paper through a cold chamber before drying. These expedients are more or less eiective, depending on the colloidal characteristics of the impregnating material and the size of the pores of the paper.

It will be appreciated that the denser the paper and the finer the pores, the more resistant such paper is to impregnation by viscous or colloidal solutions or emulsions. As an example: Many attempts have been made to provide paper containing rubber as a binder, in view of its remarkable toughening properties. Such attempts have been only moderately successful, and in the successful instances there are important limitations to the type of fibrous base which may be used and the adaptability of the apparatus and product.

In the use of one type of apparatus there is introduced into the beater engine, along with the paper or other fiber, a quantity of liquid rubber latex, which is a suspension of rubber particles of colloidal size, in a watery serum. However, due to the pronounced tendency of such ordinary latex to coagulate and precipitate, in order to make such a combination of materials suitable for running on a paper machine, it is necessary to protect or cover the rubber particles with some suitable agent so as to prevent stickiness and be less affected by the mechanical action of the beater and paper machine. Such materials are, for example, colloidal clay, blood albumin, and certain others, all of which are practically nonadhesive when dry. When such a mixture of fiber and rubber particles is run up into paper by the elimination of most or all of the water, it Will be recognized that the particles still carry their protective coat of non-adhesive colloid, and that this coating serves to reduce their stickiness and binding qualities, preventing them from coalescing completely when dry to form a continuous film Within the paper fibers. As proof of this, it is a well known fact that paper made by beater sizing with latex has much less strength and Water resistance for an equivalent quantity of rubber than paper which, for example, has been made by saturating with a thin rubber solution.

In the production of asbestos rubber sheet packing, the standard machine uses a rubber cement-asbestos mixture, which is gradually built up on a set of calender rolls, one hot and one cold, by evaporation of the solvent. An equivalent material made by the use of latex and asbestos mixed into the beater and run oif on a paper machine must contain almost twice as much rubber for the same physical properties.

As a further instance, it is well known that some of the finest Writing and printing papers are produced by the application of glue solution to dry paper. It is recognized, however, that this process is only applicable to very thin dense papers, and that it is quite unsuitable for dense thick calipers, in that the glue solution does not penetrate suiciently for the binder effect to be at all marked in the interior of the paper.

It is an object of the present invention to produce saturated paper or board wherein the binder is uniformly distributed throughout the bers, said product being characterized by having had the binder incorporated immediately after the paper or board was in the form of a newly formed, but self-sustaining, wet web. In the preferred embodiment of the apparatus, the bers are felted in any desired conventional manner on the blanket or wire of the paper forming machine and removed entirely from said blanket or wire after rst removing sufficient water to insure that the newly formed wet web is self-sustaining at the time of removal. The self-sustaining wet web is transferred to a carrier, on or by which it is supported during saturation. The carrier preferably takes the form of an endless screen designed to permit suicient saturation and at the same time providesupport for the wet web during saturation. It is to be particularly noted that the wet web is made selfsustaining and the ber formation is completed (and not destroyed by subsequent saturation) before being separated from the blanket or wire of the paper machine. It is also tobe noted that the wet web is removed entirely from the blanket or wire of the paper forming machine and transferred to an independent carrier, designed for saturation and not for paper forming. It is well known that a paper forming blanket or wire must have relatively thin pores to permit of escape of water while preventing escape of bers; whereas the saturating screen utilized in the present invention is provided with relatively large pores, only small enough to preserve the bre formation and at the same time large enough to offer no resistance to the passage of saturant into and out of the web without crushing or distortion of the web under pressure.

'Ihe wet web, supported by the screen, is saturated with an excess of the saturant under such conditions that its thickness is increased, while at the same time the ber formation is not loosened to an extent that the formation cannot be restored to the same relative condition it was in as it left the paper forming machine. The saturated web is then condensed by pressure without crushing, and the condensed web is then subjected to drying.

There are many advantages accruing to the use of the apparatus of the present invention. The original ber alignment formed on the paper forming machine is maintained and preserved during the saturating step. 'Ihe bers are distributed and closely associated in a matrix of saturant and with the removal of Water, the bers are more closely associated and distributed in a matrix of binder and each ber is surrounded by a lm of binder. Thus, there is a uniform distribution of binder in a bonded product.

It will be appreciated that distention of a mass of paper bers will occur when this mass is in the formof anewly formed wet web in contact with an excess of water or watery fluid, and I have chosen this physical condition of the bers as the condition in which a saturant or binder material can most easily be entered within the brous mass and between the bers. However, a thoroughly soaked and distended web of paper bers has not the strength to carry its own unsupported weight in a watery liquid for any distance such as is necessary in a continuous saturation process. Therefore, unless bers in this distended condition are supported and prevented from disintegrating by their own weight or other mechanical eifect into pulp, any previous formation, alignment, intermingling or felting of bers which are previously produced on the forming elements of the paper machine will be destroyed. Again, besides the support of the web, it must be saturated under such conditions that the brous structure in the delicate distended condition will not bev materially disturbed. 'Ihe thickness of the saturated web in my saturating process is directly comparable to the thickness of the web of paper ber during the period of its formation from the pulp, and before it has been materially densied by pressing or vacuum.

'Ihe most suitable backing or support to which such a mass of bers will adhere, or on which it may li during saturation, is a ne mesh screen of metal, wire or open mesh cloth, the cleaning of which is, of course, relatively simple.

'I'he relative position of the screen, distended web and aqueous saturant should be such that thorough impregnation of the bers with the saturant is obtained.

This may be done in several ways:

1. 'I'he wet web, while held against, or adhering to, the surface of a rotating cylindrical wire screen roll by an endless screen belt, may be carried below the surface of the saturating liquid so that it is completely immersed therein.

2. The wet web may be carried between two synchronized, endless screen belts, saturant being sprayed or gently poured on the upper belt and passing through the upper belt to the web,

while the bottom of the web is saturated by an overowing reservoir of liquid saturant applied to the lower belt and passing upwardly through the latter to the underface of the web.

3. The web may be passed into contact with the surface of a wire screen roll rotating in a bath of saturant, saturant being gently sprayed on the top of the wet web from a nozzle or other discharge disposed immediately above the screen roll, excess saturant passing through the web and falling by gravity through the screen roll into a vat in which the screen roll rotates.

4. The web may be carried on the surface of an endless screen belt, saturant being applied to the upper surface of said web through a nozzle or other discharge disposed above and in the path of travel of the endless screen belt, excess saturant passing through the web and being removed by suction maintained on the under face of the endless screen belt. The suction assists in drawing the saturant through the web. The endless screen belt itself passes through a bath of saturant maintained in a vat whereby the-under face of the wet web which contacts the upper face of the endless screen belt will have saturant applied thereto from -the surface of the screen belt.

A further condition which adds to the rapidity and certainty of thorough'impregnation, according to the present invention, is that the web which is taken from the paper machine has, of course, lost considerable of the water which was associated with it during the actual ltering or formation on the screen' or cylinder of the paper machine (its maximum distention), and when this web is again immersed in a watery uid, it swells and distends again. v

It should be understood that by use of the term web, I mean not only a single thin web which may be formed on a single cylinder mold of a wet machine or screen of a Fourdrinier machine, but also a greater thickness which may result from the plying oi' two or more wet webs, as in a multi-cylinder paper machine. or of a single thicker web which may be made by loading a Fourdrinier machine heavily. Dependent upon the freeness of the stock, this film may have a maximum thickness of .030" on a Fourdrinier, or .100 on a multi-cylinder machine. It is evident that a dense or heavy web will not saturate or distend as quickly as a thinner web, but this retardation is overcome by a longer period in the saturant. The same retardation is noted in the case of dense webs comprising fine short fibers, as against loose webs comprising longer, coarser fibers.

In the drawing, Fig. 1 is a diagrammatic side elevational view, partly in cross-section, of apparatus for carrying out operation (l) Fig. 2 is a similar view of apparatus for carrying out operation (2); and

Fig. 3 is a similar view of an apparatus for carrying out operation (3);

Fig. 4 is a similar View of apparatus for carrying out operation (4) Fig. 5 is a fragmentary detail view illustrating the transfer of a saturated web from a wire screen, such as those shown in Figs. 1, 2, 3 and 4.

Referring to the drawing, and more particularly to Fig. l, I have shown the conventional rotary foraminated cylinder I rotating in the vat 2 containing pulp solution 3. Suction is maintained on the interior of the kcylinder i by conventional suction conduit 4 communicating with a source of vacuum. The felting cylinder I is immersed in the pulp suspension and rotates in the direction of the arrow. A film of felted fibrous stock 5 forms on the surface of said cylinder and is carried upwardly out of the vat, where said newly formed wet web is transferred to a continuous blanket 6, the couch roll 1 assisting in the transfer. The structure Ajust described and the method of operation are conventional.

According to the present invention, the wet web 5 is separatedfrom the blanket 6 at the point A, the endless blanket being trained around roll 8, and the wet web being brought into contact with the endless screen belt 9 which is trained around rolls I0, Il, I2 and I3. The rolls I0 are disposed beneath the level of saturant I4 in vat I5. Disposed above the vat and adapted to rotate in the bath of saturating material is a rotatable screen roll I6 driven by shaft I1 suitably journaled in a conventional way. The arrangement is such that the wet web 5 has sufficient water removed from it to make it self-sustaining, after which it moves first into contact with the upper surface of the endless screen belt 9 and is then carried into the space between said upper surface and the surface of the screen roll I8. The sheet is then caused to travel through the bath of saturant Il and, after the desiredtime of immersion, is removed from said bath, being carried by the screen to the make-up roll I8. The dolly roll II functions, in combination with the make-up roll I8, to couch the saturated web whereby to condense it without crushing. The saturated, condensed web 5 may wind around make-up roll I0 and the plies of the wet web may adhere together to the thickness desired. intermittently, the plied sheet may be stripped from the make-up roll in a conventional manner. Make-up rolls are usually provided with a longitudinal slot (not shown) and when a web has built up on the roll to the desired thickness, a

knife may be passed through the web and into the slot, and the wet plied web stripped from the roll. However, I do not wish to limit myself in any way to the steps which may take place after condensation,`since, if desired, instead of winding the web upon a make-up roll, said web may be pressed, dried and subsequently calender-ed, or any other desired operation may be performed upon the same.

Referring particularly to Fig. 2, another type of apparatus for saturating a wet web according to the present invention is illustrated. In Fig. 2 the self-sustaining wet web 5' may be formed on any suitable paper forming machine (not shown), separated from the blanket or wire of the paper forming machine, and transferred to endless screen belt 9', which is trained around rolls I0', I2 and I3. Roll I0' may be a solid roll, whereas roll I2' may be a screen roll.

Mounted above the endless screen belt 9 is a second endless screen belt I9 trained around solid roll 20 and screen roll 2|, mounted on suitable shafts journaled in suitable bearings. Tension is maintained on screen belt I9 by tension roll 22.

The newly formed self-sustaining wet web 5 is carried on the upper surface of endless screen 9' into the space between screens 9' and I9 to the point where saturant is sprayed from nozzle 23 onto screen I9, passing through the latter onto the upper surface of wet web 5'. The two travel ling screens 9' and I9 are synchronized. The roll 2U is so disposed as to cause the endless screen IS to travel at a slight sloping downward angle for a portion of its travel just above the web 5' to provide room for expansion of the web when saturated. Too great a separation of the screen and too much ilow of saturant may cause distortion of the web. An overflowing reservoir of saturant, illustrated diagrammatically at 2l, is disposed in contact with the screen 9 below the web 5 and preferably immediately below the nozzle 23. saturant is supplied to the reservoir 24 at such a rate and at such volume that the saturant continuously overflows onto the surface of the belt 9', passing through said belt onto the lower face of the web 5'. Through the medium of the nozzle 23 and overflowing reservoir 2l. both surfaces of the web are brought into contact with an excess of saturant, which saturant freely flows through the wet web. Excess saturant may be removed in any desired way. The relative positioning of the screen belts 9 and, I9 is such that the web is conlined therebetween so that the ber formation is not distorted. Squeeze rolls 25 function to partially condense excess saturant and the sheet is carried by belt 9 to makeup roll I8. A dolly roll II' is provided, which functions in combination with make-up roll IB' to couch and further condense the sheet.

Referring particularly to Fig. 4, another form cf apparatus is shown which may be adaptable in carrying out my invention. Web 5" may be formed upon any suitable paper making machine (not shown) and may be brought into contact with the upper surface `of rotatable screen roll 9 which is adapted to rotate in and be submerged by the bath of saturant I6" contained in the vat Il" during a port-fon of its travel. While the wet web is passing over the upper surface of the wire screen roll 9". saturant is sprayed on the upper surface thereof through nozzle I0", as illustrated. The nozzle I0" gently sprays an excess of saturant on the surface of the sheet, which excess passes through the web and excess adhering to either surface through the screen roll 9", collecting with the pool of saturant I6". The saturated wet web may be wound up on make-up roll 20".

Referring to Fig. 3, the wet web 5L is carried by blanket 6IL to the point A where it separates. The wet web 5a is then brought into contact with endless wire screen 9, trained around rolls I0, and |28. Roll Illa is preferably a wire screen roll, whereas rolls and I2a may be solid rolls. Roll Il)a is adapted to rotate in a bath of saturant Nifl contained in vat I1, As the wet web 5e is carried along on the upper surface of the endless screen belt 9, saturant is sprayed on the upper surface of the wet web through nozzle ISH. The arrangement is such that preferably an excess of saturant is applied through the nozzle |39-, which excess is removed by means of suction maintained in the suction box |43. The suction maintained in the box I4al also assists in drawing the saturant through the wet web. Subsequent to removal of the excess saturant through the medium of the suction box I4l the wet web is condensed. In the modification illustrated in Fig. 3, condensation takes place by the couching effect of dolly roll I3a and couch roll the condensed and saturated sheet being led from the condensing mechanism to conventional driers instead of being wound on a makeup roll as in the other modifications.

As an illustrative example of the invention, I may use rubber latex as a saturant, and a web comprising well beaten sulphite pulp being concurrently formed on a paper machine. This wet web is made self-sustaining, removed from the blanket or wire of the paper forming machine and led or threaded into the saturating structures illustrated in Figs. 1, 2, 3 and 4 of the drawing. 'Ihe web speed on the paper machine and through the saturating structure is synchronized to prevent tearing of the wet web at the point of threading or beyond. The web is distended by the excess of liquid saturant and becomes thoroughly saturated.

On leaving the saturant after saturation, any may, if desired, be removed `by the passage of the saturated web by or in contact'with a suction chamber, or between adjustable press rolls and the saturating cylinder. The adjustable press rolls also serve to densify the web again so that it may be subjected to mechanical handling. 'I'he web may be then passed on and pressed, dried, calendered and wound into rolls. Where rubber latex is the saturant, vulcanizing agents, accelerators, antioxidants, preservatives, fillers or the like, may be added, if desired, either to the paper stock or to the saturant.

The sheet when dried is a mass of densely compressed paper ber permeated and bound by a substantially continuous film of binder.

It has been stated above that the application of rubber latex to paper fiber in a beater engine for the formation of a saturated paper is only partially successful because of the fact that the quantity of rubber required for a specific effect is greater than that required by a saturation process. By the saturation process described above, I am able to obtain higher rubber eiiciency because of the formation of continuous lms of binder within the fibers.

The proportion of introduced binder or other material may be controlled in the finished paper or board by the concentration of the binder in the saturating solution, and by the densifying of the web between the press rolls after saturahencethe proportion of introduced tion. Due to the possibility of widely varying the thickness of the web leaving the saturating machine, the volume of absorbed saturant and material may be regulated within wide limits.

Many other binding or sizing materials which are not susceptible to introduction in the beater engine for various reasons, such as too great solubility in water or sensitiveness to mechanical action, etc., may be introduced with safety and efhciency by this process into webs of any desired composition. The web may be composed of long, unbeaten ber such as cotton, or, at the other extreme, short highlyhydrated fibers produced by long beating. It may comprise asbestos, filling materials or pigments, or materials intended to react with the binder material or size later applied. Some examples of these binders or sizing materials are: Alkaline phenolic resin solution, alkaline casein solution, starch solution, alkaline shellac solution, glue solution, diluted viscose, sodium silicate solution, oil or asphalt emulsions, soap solutions, rosin size, etc., or any desirable combination of these or other binding or sizing materials. Most of these are quite inoperative and ineffective when applied in the beater engine, but will produce a full binding effect when saturated by this method. Furthermore, there is no intent to limit this process of saturating to binders or sizing materials, as soluble salts, dyes, suspensions or pigments, clay, or reagents to act on the paper ber or on materials contained in the web may be employed using the principles described above. In general, any material which may be carried in water, dissolved or suspended, may be introduced effectively into paper ber by this method to impart many new and desirable characteristics to the finished paper or fiber board. To those familiar with binder materials and paper, this method `of saturating fibers provides the possibility of utilizing many combinations heretofore impractical, and of producing many new and useful products.

From the foregoing, it will be apparent that my wet web must be made in such a way that it is in an "expansible or distensible condition when it is passed through the saturation zone. To produce such a web, as has been herein explained, the duration of beating of the fibers should be limited so that the fibers are in a relatively long condition, or, in the event that short fibers are employed, the quantity of sizing, if employed at all, must be limited, and the quantity of water retained in the wet web after removal of the excess thereof, must be such as to leave the wet, but self-sustaining web, in the condition stated.

By the use, therefore, of the terms "expansible" or distensible, as employed herein and in my claims, I intend to define a felted fibrous web having the capability of increasing in thicknessby the presence of an added liquid, when undergoing the saturation step, whereby to permit the bers toI change or adjust their relative positions for the purpose of enlarging the pores or interstices without, however, complete dissociation of the fibers, inasmuch as thev hooked" or inter-tangled relationship of the fibers continues to' exist. 'I'hat is to say, there is an increase of the vertical component of their direction which may be roughly compared with a lazy tong structure.

Such a distensible web, may, therefore, after saturation and concomitant distension or expansion, upon condensing, resume the fiber relationship or formation existent in the web before saturation. In other words, the paper making characteristics of the web remain substantially unmodified by the saturation thereof in view of the fact that the fibers remain hooked" or intertangled when the web is distended in the vpresence of the excess of saturant.' Such a wet web therefore, when immersed in a saturation bath, such as, for instance, latex, assumes what may be termed, for want of a more apt expression, a floating condition; that is to say, the fibers tend to float in the excess of liquid of the saturating bath, but because of the hooked or intertangled relationship, as aforesaid, they cannot entirely separate and, therefore, the floating is restrained to a condition short of complete separation.

The wet web may be further characterized by the fact that it would disintegrate when immersed in a saturating bath if it were not supported by a porous carrier; moreover, the web may be characterized by the fact that a single and rather rapid passage thereof through the saturating bath will completely saturate the same and, in fact, provide an excess of saturant therefor, as distinguished from webs of such a character as would require a rest period or which would require no carrier when undergoing immersion during the saturating step.

As herein stated, the structure resulting from my process is a felted fibrous sheet composed of a plurality of bers, individually coated with a binder, the binder constituting a continuous connecting medium for the individual fibers and being present in the sheet without substantially disturbing the 'paper making characteristics or the structural foundation of the sheet as it has been felted before the saturation step. In other words, the modifying material, such as rubber from latex, exists in a continuous phase and serves to both individually coat and connect the fibers contained therein without substantially altering or changing the felted fibrous arrangement of the fibers. Therefore, the resultant structure has increased flexibility, tensile and tear strengths. Moreover, in view of the fact that the web is wet when undergoing saturation, there occurs subsequent to saturation, a shrinking action of the fibers which causes the same to more tenaciously hook together and to the connecting medium, such as, for example, rubber from latex. Of course, both the saturant and the wet fibers shrink together and at the same time during drying.

I claim as my invention:

l. In combination with means for felting fibers in aqueous suspension into a relatively wet web, of means for saturating said wet web comprising synchronously moving foraminated surfaces, the upper of said surfaces consisting of a rotatably mounted screen roll and the lower of said surfaces consisting of an endless porous screen, means for passing said wet web into contact with. and confining said wet web between, the opposed faces of said foraminated surfaces, a bulk supply of saturant, means for passing said wet web while confined between said foraminated surfaces through said saturant, means beyond the bulk supply for releasing said wet web from said confinement below the horizontal plane of the axis of said screen roll, means immediately adjacent said releasing means for condensing the web to remove excess liquid, a second condensing means remote from said first mentioned condensing means, for removing remaining excess saturant from the web, and means for leading the foraminated surface carrying said web from the first mentioned condensing means to the second mentioned condensing means.

2. In combination with means for felting fibers in aqueous suspension into a relatively wet web, of means for saturating said wet web comprising synchronously moving foraminated surfaces, the upper of said surfaces consisting of a rotatably mounted screen roll and the lower of said surfaces consisting of an endless porous screen, means for passing said wet web into contact with, and confining said wet web between, the opposed faces of said foraminated surfaces, a bulk supply of saturant, means for passing said wet web while confined between said foraminated surfaces through said saturant, means beyond the bulk supply for releasing said wet web from said confinement below the horizontal plane of the axis of said screen roll, means immediately adjacent said releasing means for condensing the web to remove excess liquid, a second condensing means remote from said first mentioned condensing means, comprising a couch roll and an offset dolly or pressure roll for removing remaining excess saturant from the web, and means for leading the foraminated surface carrying said web from the first mentioned condensing means to the second mentioned condensing means.

3. In combination with means for felting fibers in aqueous suspension into a relatively wet web, of means for saturating said wet web comprising synchronously moving foraminated surfaces, the upper of said surfaces comprising a horizontally rotatably mounted screen roll and the lower of said surfaces consisting of an endless porous screen, means for passing said wet web into contact with, and confining said wet web between, the opposed faces of said foraminated surfaces, a bulk supply of saturant, means for passing said wet web while confined between said foraminated surfaces through said saturant, means beyond the bulk supply for releasing said wet web from said confinement contiguous to the liquid level maintained in the bulk supply and below the plane of the horizontal axis of said rotatably mounted porous-surfaced cylinder, and means for thereafter condensing the web to remove excess liquid.

4. In combination with means for felting bers in aqueous suspension into a relatively wet web, of means for saturating said wet web comprising synchronously moving foraminated surfaces, the upper of said surfaces comprising a horizontally rotatably mounted screen roll and the lower of said surfaces consisting of an endless porous screen, means for passing said wet web into contact with, and conning said wet web between the opposedfaces of said foraminated surfaces, a bulk supply of saturant, means for passing said wet web while confined between said foraminated surfaces through said saturant, means beyond the bulk supply for releasing said wet web from said confinement contiguous to the liquid level maintained in the bulk supply and below the plane of the horizontal axis of said rotatably mounted porous-surfaced cylinder, comprising a rotatably mounted roll exerting pressure through the endless screen against the web and the poroussurfaced cylinder contiguous to the zone of release, and means for thereafter condensing the web to remove excess liquid.

5. An apparatus comprising in combination, means for felting fibers from an aqueous suspension to form a` continuous self-sustaining wet web, means for substantially increasing the liquid content oi' said wetweb to such an extent that the web is no longer self-sustaining, including a rotatably mounted screen roll means for supporting said wet web to prevent disintegration and distortion and preserve the original fibre formation, means for thereafter separating excess liquid from said web to restore said web to self-sustaining condition without disturbing its original fiber formation, and means for separating said selfsustaining web from its support.

6. An apparatus comprising in combination, means for felting fibers from an aqueous suspension to form a continuous self-sustaining wet web, means for substantially increasing the liquid content of said wet web to such an extent that the web is no longer self-sustaining, including a rotatably mounted screen roll comprising synchronously moving foraminated surfaces between which the web is confined, a supply of saturant, means for passing said wet web While so confined into contact with said saturant, means for supporting said wet web to prevent disintegration and distortion and preserve the original fibre formation, means for thereafter separating excess liquid from said web to restore said web to selfsustaining condition without disturbing its original bre formation, and means for separating said self-sustaining web from its support.

7. An apparatus comprising iny combination, means for felting fibers from an aqueous suspension to form a continuous self-sustaining wet web, means for substantially increasing the liquid content of said wet web to such an extent that the web is no longer self-sustaining, including a rotatably mounted screen roll means for supporting said wet web to prevent disintegration and distortion and preserve the original fibre formation, means for thereafter separating excess liquid from said web to restore said web to self-sustaining condition without disturbing its original bre formation, comprising means for exerting `pressure on the web while said web is supported against disintegration by the supporting means,` and means for separating said self-sustaining web from its support.

8. An apparatus comprising in combination, means for felting fibers from an aqueous suspension to form a continuous self-sustaining-wet web, means for substantially increasing the liquid content of said Wet web to such an extent that the web is no longer self-sustaining, comprising synchronously moving foraminated surfaces between which the web is confined, a supply of saturant, means for passing said wet web while so confined into contact with said saturant, means for supporting said Wet web to prevent disintegration and distortion and preserve the original fibre formation, means for thereafter separating excess liquid from said web to restore said web to selfsustaining condition without disturbing its original fibre formation, comprising means for exerting pressure on the web while said web is supported against disintegration by the supporting means, and means for separating said self-sustaining Web from its support.

9. An apparatus comprising in combination, means for felt'ing fibers from an aqueous suspension to form a continuous self-sustaining wet web, means for substantially increasing the liquid content of said wet web to such an extent that the web is no longer self-sustaining, comprising synchronously moving foraminated surfaces between which the web is confined, the upper of said surfaces comprising a rotatably mounted screen roll and the lower of said surfaces comprising an endless porous screen, a supply of saturant, means for passing said wet web while so confined into contact with said saturant, means for supporting said wet web to prevent disintegration and distortion and preserve the original fibre formation, means for thereafter separating excess liquid from said web to restore said web to self-sustaining condition Without disturbing its original fibre formation, and means for separating said self-sustaining web from its support.

' IZADOR J. NOVAK.

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