US2017339A - Reenforced fibrous layer - Google Patents

Description

Oct. 15, 1935. F. L.' BRYANT Er AL REENFORCED FIBROUS LAYER -Film Nov. 11, 1953 2 sheets-sheet 1 Oct. l5, 1935.

F. L. BRYANT ET AL REENFORCED FIBROUS LAYER Filed NOV. 11, 1935 2 Sheets-Sheet 2 Patented Oct. 15, 1935 UNITED STATES PATENT orFiCE aEENFoRCED FrBRoUs LAYER Frank L. Bryant, East Orange, and Gustave S. Mathey, Elizabeth, N. J., assignors to Cellufo'am Corporation, Chicago, Ill., a corporation of The present invention is directed to a reenforcement of layers of brous material of the character set forth and described in the Bryant Patent No. 1,740,280, issued December 17, 1929, although the material maybe modified to include certain features described in the Bryant Patent No. 1,841,785, issued January 19, 1932, as Well as certain features described in the Bryant application Serial No. 599,329, filed March 16, 1932 issued as Patent No. 1,966,437, dated July 17, 1934.

The fibrous material which furnishes the basis for the layer of the present invention 'is preferably formed of celluiosefibers, which are first mixed with a large percentage of water to which is added a quantity of saponin or similar foam forming ingredient, after which the mix is agitated to cause foaming and distension of the bers, and in this condition is flowed upon the foraminous bed of a Fourdrinier machine in the form of a relatively thick layer which is fed forward in an uncompressed state and partially drained and afterwards dried under conditions which preserve the layer in its fluffy or distended "condition, If desired, waterproofing or fireproofmg ingredients may be added to the mix, and the advancing layer may be subjected to vacuum While being carried forward on the Fourdrinier l gether.

machine in such manner as to form a relatively tough coherent skin on the surface of the layer, and furthermore, if desired, relatively long lhairlike bers may be incorporated into the mix'for the purpose of binding the layer more firmly to- The nature of the layer, and the various methods of modifying its character, texture and qualities, are described in full detail in the patents above mentioned, and in the process and product of the present invention it will be understood that it is the intention to utilize a layer of the general character indicated in the original Bryant Patent No. 1,740,280, which may if desired be modied in one or more of the ways indicated in the remaining Bryant patents.

The present invention is directed to the incorporation into the layer itself'of a gauze or similar fabric, which unites with the layer in such a way as to strengthen and reinforce the layer and afford increased tensile strength which is not present in substantial degree in the felted layer formed in the manner set forth in the above named patents and application. The gauze or other fabric is applied to the layer during the formation lthereof in such` a way as to cause the cellulose fibers o'f the layers to intermesh with the fabric and become interspersed into the interstices thereof so that the fabric is, to some extent incorporated into the texture of the layer either by being bodily imbedded Within the lnteriorof the layer or applied to the surface thereof while the layer is inthe formative stage, so that a close "5 intermeshing4 of the fibers occurs. The fabric may be applied to the surface of the layer while the mix is being flowed onto the bed of the'Fourdrinier machine, and at a time when the mix contains a very large percentage of l0 water, so that during the draining and drying operation the fabric will become intermeshed or entangled with the surface bers of the layer insuch a manner as to cause adherence of the fabric to the surface, or if desired the fabric ca n be spread upon the surface of an under layer of the mix while being flowed upon the bed of the Fourdrinier machine and a second layer deposited from above, in which case the fabric will be completely imbedded within the interior of the completed product by the coalescence of the two layers while in the semi-liquid state and the intermeshing of the fibers through the interstices of the fabric. It will therefore be understood lthat where reference is made to the intermeshing of the fibers with the texture of the fabric, it is intended to cover either the surface application of the fabric'or the complete imbedmentthereof, as the case may be, since in either case the intermeshing is one which serves to retain the fabric in place and'to afford suiiicient adhesion to reenforce the texture of the layer in such a way as to prevent rupture under ordinary conditions of use.

The reenforced layer of the present invention is designed particularly for use in surgical dressings, or for antiseptic purposes, or under various conditions of use' in which an absorbent layer is desired, although by suitable treatment lone or both of the surfaces may be proofed or rendered 40 l non-absorbent, or otherwise modified in accordance with theprinciples particularly set forth in the Bryant Patent No. 1,841,781, and the Bryant application Serial No. 599,329. It will also be understood that although the method of `forming the layer as described and illustrated in the Bryant Patent No. 1,841,785 furnishes a convenient and desirable method of forming the mix and owing it out in layer form and under conditions which readily permit of the application of the gauze or similar reenforcement described in the present invention, it is not the intention to limit the method nf applying reenforcement to the layer, since any convenient method 4may be employed which permits the fabric layer to be intermeshed with or completely imbedded within the body of the fibrous layer While still in the formative stage and under conditions which provide for the interspersion or intermeshing of the fibers 5 with the texture of the fabric in such a Way as to unite the one to the other.

In order to better define the nature of the present invention, reference is had to the accompanying drawings, wherein,-

*l Figure 1 is a perspective view of a section of the material showing the gauze reenforcement applied to the surface thereof;

Fig. 2 is a perspective view showing the fabric imbedded within the interior,I and the surface l layer partly broken away to better expose the fabric; y

Flg.l3 is an enlarged sectional detail showing the manner in which the fibers of the layer are interspersed through the interstices in the fabric g reenforcement;

Figs- 4, 5 and 6 are longitudinal sectional views of successive portions of one and the same machine designed to continuously produce layers of reenforced distended material; and

y2li Fig. 7 isa detail showing a modification designed to discharge the material in upper and lower layers to imbed the reenforcement Within the body of thematerial. The product of the present invention consists of'a layer A of distended fibers (preferably of 1 desired, one or more of the exterior surfaces of the layer may be more densely compacted to afford a paperlike surface skin C which servesfto toughen the surface in cases where such a texture `is desired.

As illustrative of asuitable method of practicing the present invention, the following description is given:

'Cellulose fibers are 'introduced into a regular paper stock beater of the Holland, Niagara, or Jordan type,with suiilcient water to give the 'proper consistency to the mix about three percent (3%), and subjected to the action of the beater for a suiiicient'length of Itime to produce 50 the'desired vdegree of hydration. This period may be varied, depending upon the condition of the raw fibersand upon the extent to which it is desired to gelatinizethe surfaces of the fibers, but for most purposes treatmentof an hour will serve to give to 'the fibers the desired degree of hydration. Wherey the action is continued sufficiently to soften the surfaces of^ the fibers, a gelatinizing effect occurs, which modifies the surface condition of the fibers and their capacity" Y 50 to imbed `themselves into one another4 at ,the points where they contact or intersect, so that they are thus in a better condition to felt vor intermesh together than in cases where a lesser 7 0 After the fibrous materials have been sufficiently beaten andvhydrated, it-is necessary to incorporate with the liquid mixture a suitable quantity of bubble forming or foam forming ingradient of the character set forth in' the Bryant Patent No. 1,740,280. It may also at this stage be desirable in certain cases to incorporate with the mass a quantity of lhair or other relatively long fibrous material where it is desired to secure a more coherent texture in the completed product, although in the present'instance the use of 5 the gauze or similar reenforcing fabric will ordinarily render it unnecessary to provide for additional methods of reenforcement.

The foam forming ingredient which is preferred is saponin, which may be added in the 10 proportion of substantially one part of saponin vto four hundred parts of water in the mixture,

and after the addition of saponin or other bubble forming ingredients, the mixture, either with or without the addition of proofing agents, is 15 subjected to agitationin theA manner set forth in the Bryant Patent No. 1,740,280 for a sufficient period of time to cause the mass to distend and assume a foamy condition through the action of the bubble forming or foam forming in- 20 gredients, and until the mass has expanded to about two `and a half times its original liquid volume. f

Where it is desired to waterproof or flreproof the layer, various ingredients of the character 25 particularly described in the Bryant application Serial No. 599,329 maybe added to the mix and v,incorporated with the fibers, either before or during the agitating operation.

.to cause a fiuxing of the minute wax particles onto the fibers to form a waterproof coating or covering for each fiber. In the above process it will be noted that the foaming and waterproofing 45 steps are concurrently performed in a single operation, which is desirable from the standpoint of economy in cases Where other considerations do not indicate the necessity for performing the steps separately. 50

As an example of a iireprooflng operation, which Wer prefer incertain cases, we take a slurry of fibers with water to which is added a foam forming ingredient such as saponin, together with u 15 parts of borax, 6.5 parts of boric acid based on 55 the -Weight of .water used, the whole being whipped to form a stable foam with the fibers incorporated therein, and afterwards formed to shape and dried in the manner previously described. 00

Other methods of proofing or modifying the fibers for the purpose of adding special qualities to the product are in contemplation, but it will be understood that the presentv invention is directed mainly to the use of a gauze or similar fab- B5 ric for purposes of reenforcement, and that the ,special characteristics of the fibers themselves `rnay in each case be modified with a View of imparting to them the desired qualities, which will depend in large measure upon the use for which the reenforced layer isl intended.

Where the layer is intended for an absorbent bandage, it will, of course, be inadvisabe to use any ingredients which will in any way impair its absorbent properties, although in some cases it v(it) ,iorcement while maintaining the absorbent properties in the mix intended' for application on the other side of the reenforcement. This will result in a bandage or the like which possesses full absorbent properties on one side only, with water repellent properties on the opposite side.

The method of owing themix in the form of a. layer onto the surface of a Fourdrinier machine, and of subsequently drying the layer while still in uncompressed or distended condition, is fully set forth in the Bryant Patent No. 1,841,785, and it is not deemed necessary to describe the process and mechanism in detail. However, a brief description of the process and mechanism, slightly modified to provide for the feeding of the gauze or other reenforcing agent, will be gi'ven, with special reference to the illustrations in Figs. 4 to 7 of the drawings.

After the bubble forming ingredients have been added to the mass, with or without the addition of modifying agents, the mass is poured into a tank I0, within which the material is agitated and distended by the. action of `propeller blades I I-II mounted upon a vertical shaft I2, which is driven from a motor I3 or other source of power.

The shaft I2 is preferably locatedv off center with respect to the tank I0, which is preferably circular, so that as the material is driven outwardly by the action of the propeller blades it will sweep around the wall of the tank and be alternately directed inwardly toward` the propeller blades and outwardly and away therefrom during its circuit around the tank. While the tank as shown .is of cylindrical or circular forma-4 tion, similar results may be obtained by the use of a barrel shaped tank or one otherwise configured. v

The blades of the propeller are preferably formed with downwardly turned tips, III, while the body of each blade is turned upwardly, with the result that when rotating, the blades will have the effect of Iimparting a combined downward and outward thrust to the material, which gives a Vortical motion, and which, combined wth the lsurging action caused by the eccentric relation of lthe blades to the tank, serves to thoroughly agitate the material without any tendency to additionally break up the minute fibers.

After the material has been thus agitated for a sucient period to cause it to distend through the action of the bubble forming or fcam forming ingredients to about two and a halftimes its original liquid volume, and after the hair or other material, if any, has been added andhas become thoroughly impregnated with and distributed evenly throughout the mass, and while the material is in a creamy state due to the presence of the minute bubbles ,formed therein, it is discharged in the form of a layer from a spout I5 located near the bottom of the tank, and onto the traveling or foraminous bed or carrier I6 of a Fourdrinier machine. i

The bed is preferably formed of ne mesh wire screening and is carried upon supporting rollers I1 and passes around a front idle roller I8 and a rear power driven roller I9. Immediately in advance of the power driven roller, the belt cr carrier passes downwardly over a supporting roller 20, and thealower turn of the belt or carrier passes over a rear roller 2|, a forward guideV roller 22,

and under a. tension" roller 23.

Near the forward end of the Fourdrinier machine there may be located'what may be termed a heavy suction box 24 connected by a suction pipe 25 with a suitable source of vacuum adapted to maintain a relatively heavy vacuum of approximately ve inches in the heavy suction box, 5

the purpose of which is to momentarily subject the layer of material, immediately after its delivery onto the bed of the Fourdrinier machine, to

a suiiiciently heavy suction to draw down and compact theunder surface of the layer of rriate- 10 rial, thereby causing the fibers to cohere and compact together in the formation of a tough paperlike surface skin, where such a skin is desired in the completed product.

Near the rear end of the Fourdrinier machine 15 are located a series of relatively light suction boxes 2G connected bypip'es 21 with a suitable source of vacuum 28 adapted to maintain a light Isuction of approximately three inches of vacuum in the suction boxes, which is a much lless 20 degree of vacuum than is commonly employed in the paper making art, and less `than the vacuum in the vacuum box 24, the light vacuum boxes being relied upon to withdraw moisture, without, however, additionally compacting the body of 25 the layer of material.

In order to give proper definition to the width of the layer, gauge belts 29 of rubber or suitable composition are employed, one on each side of the bed or carrier, and vthese belts are properly 3o held and supported to rest upon and travel with the carrier and constitute side walls or flanges for gauging the depth of the layer of material and for affording a sharp or clean cut edge to the layer.

In order to secure a proper depth 'of material, which should ordinarily be ush with the lower tunis of the gauge belts, a scraper bar 30 is provided immediately to the rear of the spout I5, which serves tolevel down the layer to the level 40 ofthe gauge belts, after which vthe layer is not again subjected to any compressive or deformative action save and except the suction previously v described.

The gauge belts are mounted upon grooved rollers 3| at the forward and rear ends thereof, and the upper turn of each belt. is supported by an intermediate roller 32, which allows the lower v turn of each belt to rest bodily upon the moving carrier of the Fourdrinier machine and to travel therewith by friction without the necessity ofr providing means` for positively feeding the gauge belts.

In order to apply the reenforcing gauze or the like to the surface of the wet distended layer of material, the gauze or other reenforcing material is preferably fed from a roll 33 in position to contact the surface of the distended layer and travel therewith during the draining and drying of the layer, so that the gauze will become enmeshed within the fibers of the layer'and be held and united thereto in such a way as to secure sufficient coherence 'to subserve thepurposes of the present invention. Where it is desired, however, -to completely imbed the gauze or other re- 65 enforcing fabric within the body of the layer, it is desirable to modify the constructionsufciently to provide for the feeding of two layers of the mix and to feed the reenforcing material 'between the layers so that the upper layer will l0- be owed over the fabric. In such. case, in addition to the lower spout I5, an upper spout 34 is provided, and the gauze vor other fabric is fed from above and over a. diagonally disposedroller 35 located between the spouts, so that the fabric 75 will be imbedded as the material is discharged 4from the upper and lower spouts, and the material itself, being in the form of a wet mix, will coalesce through the meshes of the gauze or other reenforcement, thereby serving to hold the re,

enforcement permanently in place.

The reenforced layer of material A passes from the traveling conveyor of the Fourdrinier machine over a stationary shoe 36 and onto the surface of an endless carrier belt 31, the upper turn of which lies i'lush with the surfaces of the carrier IG and the shoe 36. The carrier belt 31 is carried upon supporting rollers 38 and passes under a; forward roller 39 suitably'spaced to distend th forward end of the belt and thereby cause the lower turn to move upwardly in oblique relation to the forward roller 38, as indicated in Fig. 5. The carrierl belt 31 passes a rear power driven roller ,40, and the upper and lower turns in proximity to the power driven roller are supported on guide rollers 4| and 42, respectively.

The upper and lower turns of the endless carrier 31. pass through an elongated drying chamber 43of boxlike formation, which as shown is supplied with heated air through forward, intermediate and rear ports 44, 45 and 46, respectively.

ATheiirst port` is located near the forward end of the drying chamber, while the last port occupies a position near the discharge end thereof.

`Each o f the ports, as shown in the gures, is in'duplicate, and discharges from. each side into the drying chamber at a level with the carrier therein, so that the hotair will be discharged above and below the layerof material beingy dried, and the duplicate ports in each instance communicate with side ducts 41 which pass upwardly around opposite sides of the drying chamber and receive the heated air from an air delivery duct 48. Similar delivery ducts 49 and 50 deliver the heated` air to the intermediate and rear discharge ports 45 and 46, respectively. The not air ducts receive heated air from a furnace or other suitable source of supply, and it is preferred that the hot air delivered to the forward discharge ports 4 4 be at a higher'temperature than that delivered to the intermediate and rear discharge ports, since in the wetter condition in which the material enters the drying chamber it will stand a higher drying tempera-f -5 4ture than is desirable at subsequent stagesin its f progression toward the point of delivery. The air is withdrawn from the bottom ofv the drying chamber through return ducts 5|, 52 -and 53, which communicate with an exhaust fan, not 102 shown, for the purpose of maintaining a circuit ow of heated air through the drying chamber.

The product of the present invention is adapted for numerous uses and may be made in vari-v ous thicknesses, and the texture and quality 0i' l6 the product may be varied in numerous ways.' As before stated, the product may be waterproofed on one or both sides, and the formation cfa surface skin of the desired toughness or coherence g may be included or omitted as desired. 20 Although the invention is designed particularly with reference to the formation of bandages for surgical or hygienic use, thesame general proc.- ess suitably varied may be employed in 4the production of layers intended for widely divergent 25 uses. Thus greater or less suction may be an plied to the surfaces of the layer to produce a. surface skin which. will increase the coherence of the layer, and similarly, by the use of such long bered ingredients as hair or the like, addi- 34Hv tional toughness and coherence may be added, without, however, destroying the distendedfconf- FRANK L. Barlnrr.4 GUSTAVE s. MATHEY.

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