US2208236A

US2208236A - Method of making sheet products

Info

Publication number: US2208236A
Application number: US116141A
Authority: US
Inventors: John A Wiener
Original assignee: Johns Manville
Current assignee: Johns Manville Corp; Johns Manville
Priority date: 1936-12-16
Filing date: 1936-12-16
Publication date: 1940-07-16
Anticipated expiration: 1957-07-16

Description

July 16, 1940. J. A. WIENER METHOD OF MAKING SHEET PRODUCTS Filed Dec. 16, 1936 INVENTOR John ,4. Wiener- BY a V XQ/M TTORNEY 2, 8, 3 PATEN oFFlCE V I 2.20am; METHOD OF SHEET PRODUCTS .Iohn A Wiener, Os'w'ego, N-'.-Y., minor to Jolml- Manvill 'I m cn. New York, N. 1.. a Duration-o! N f-Y k I f I Application December 16,1938,S,erlaiNo.118.141

' Y 2 Claims.

This invention relates to asheet-product'and the method. and apparatus for making the same.

It relates-more particularly, to a wall board-provided with a composition forming a smooth surface over a face thereof and being thoroughly footed inv the portion of the wallboard adjacent to the said face or integrally united to a material extending throughout the board.'

Special difliculties arise when it is attempted 10 to apply a smooth, ilrmly adhered surface coating over a thick insulating fibre board or-the like.

It is an object of the invention toovercome these difliculties and to produce a new and improved wall' board or sheet that is stiff, durable,

and adapted to be painted satisfactorily with a minimum penetration of paintand requirement thereof.

The invention is illustrated in the drawing and will be described, for the purposeofexempliflcation, in connection therewith.

Fig. 1 shows, diagrammatically, a side-view of apparatus that may be used in making the improved wall board. v

Fig. 2 is a perspective view of the product, on

Fig. 3 is a similar view of a modification of. my

improved product that is embossed during manufacture'.

In making my product, there is provided the thick felted-fibrous sheet that is to be surfaced. The hardenable surfacing composition, in fluent form, isapplied to a face thereof and forced in part thereinto. The said composition is then smoothed (ironed) and hardened.

Thus, there may be provided a sheet i that is appreciably resiliently compressible, as, for example, one of woodorbagassefibres constituting an insulating wall board and containing, suit- 40 ably, a solid, fusible material, such as a rosin size, a fusible resin or the like well distributed throughout the sheet. This sheet may be passed under and in contactwith the surface of. a coating roller 2, co'actingwlth a companion roller 3, and supportinga supply of the surfacing composition 4 in the bightwbetween-the rollers.

The roller 2' supplies over a face of the wall board an excess of the surfacing composition above that required to close and extend over the irregularities j of surface (pores or upstanding fibres) of. the. surface portion of the said sheet and above that which may pass under the roller 2. This excess. collects as a mass 5 just in advance of the position of passage of the sheet under the latter roller. Furthermore, this roller preferably compresses the sheet appreciably and exerts pressure upon the composition applied thereto. This compression and pressure serve the function of forcing a part of the composition into the sheet, so as to provide adequate footing and to reduce momentarily the thickness of. the A sheet to such an extent as to permit reexpansion and drawing'of the composition into the sheet,

after the pressure is released by the emergence s of the sheet from the space between the roller 2 8 and the rigid bed or opposed lower roller 6 of the coating machine. After being thus coated, the sheet is passed underone or more ironing rolls, such as those shown at 1 and I in the figure;

These rolls, at theirsmooth surfaces in contact with the coated sheet, move at a speed (in this case, peripheral) that is preferably exactly the same asthat at which the sheet is being advanced. In this way ridging of the coating is prevented and the smoothing of the coating is satisfactory.

These rollers are maintained at an elevated temperature, say at aboutiOO-VOO F. at their exterior surfaces. They. serve to soften any material in the board or-ingredient of the surfacing composition that is fusible at the temperature to -which the said material or ingredient is raised by the rolls. and/or to harden the composition, as by the evaporation of water or other volatile solvent or extender when the composition is one made fluent thereby, or by curing or vulcanization when the surfacing composition includes a heat-hardenable ingredient.

After passage from the machine, the sheet iscooled so that any fused, normally solid material therein is thus hardened.

Particularly desirable results are obtained and" the amount of surfacing composition required to. Iv produce a given smoothness is reduced, when the fibre sheet that is to be coated is subjected to 35 an ironing action previous to'being coated. Thus, a fibre board in dried condition, so as to be resistant to excessive decrease'in thickness on compresslon,'is moistened over its face as by a spray of steam or water 9 applied just in advance ofthe preliminary smoothingstep. The moistened sheet is then passed under the pressure ironing roller ID. as illustrated.

Also. it is convenient to support the roller 3 upon the rollers 2 and ii, as by the cradle I! which rid s at either side upon one of the said rollers'and supports the smaller roller 3 in predetermined position with respect to the roller}. In this manner, the width of opening between the rollers 2 and 3 is made subject to variation by the adjustment l3 including a screw bolt at either end of'the small rollerand serving to permit shifting of the axis of the said roller upwardly or downwardly within the ends of the cradle. 1, i i v In another modification of'the invention, an embossing roller ll may impress a desired pattern, such, for example, as that illustrated in edge view in Fig. 3, upon the fibre sheet and surfacing composition applied thereover. The configuration of the surface roller I4 is that selected to give the desired pattern 01'. embossing. The roller I I may be maintained at an elevated temperature and thus caused to embossand simultal neously heat the surfacing composition, either to soften it, as in the case of a heat-softenali le surfacing composition, or to harden it, as in the case of a composition that is hardened at elevated temperature.

10 The coating composition, somewhat exaggerated in thickness, is indicated in the drawing by the reference character l5.

Means for advancing the sheet or rotating the several rollers, in the direction shown by the arrows, are not illustrated, inasmuch as they may be conventional.

, Various surfacing compositions may be used.

1 .j'I'hus, the composition 4 may include an adhesive or binder ingredient, a finely divided solid or filler that may be a pigmentary substance, and,

V for some purposes, a wetting agent to promote penetration of the composition as applied to the board. A composition that may be used is one com- 25 prising finely divided pigmentary substance, say finely divided calcium carbonate of the grade known as whiting, in the proportion of 75 parts by weight, an adhesive, as, for example, 20 parts by weight of starch, casein, or glue, and an addi- 80 :tional binder that is incombustible, say parts of soluble sodium silicate, all made into a fluent -spaste or mixture for application by the use of water, as the extender, in suitable proportion.

When the adhesive is water-soluble, there is ll preferably incorporated into the said mixture 8.

rosin size and then alum, to cause the precipitation of a waterproofing agent.

The coating composition should be viscous to ensure smoothness of coating, say of time of out- 40 flow from a given 100 cc. pipes of about 27 to 40 seconds as compared to 22 seconds for water. Also, there'may be used a similar formula in which the silicate of soda and/or the said adhesive is replaced by a rubber composition. In

45 this case the extender may be water, as in latex,

gasoline, or benzol.

The proportions of components of the surfacing composition and/or its qualitative composition may be varied in accordance with the 60 properties desired in any particular surface coating. For instance, there has been used to advantage a composition including 66 parts of whiting, one part of starch, and one 'part of a rubber latex composition commonly known as Paracol. Also,

as there may be used a surfacing composition, made into proper consistency for application by'the roller 2, including whiting, lithopone, starch as the adhesive, iron oxide pigment, and a. wetting agent. a

so The wetting agent may be used in connection with any of the compositions described above. The proportion of the wetting agent being usually small, say not in excess of 2 or 3 parts to 100 parts of the composition.

05 Wetting agents tha may be used incl de Turkey red oil, an ethanolamine, and a diphenol hydroxide (Dowicide) and/or a sulfonated oil such as Twitchells reagent.

There may be used t advantage a surfacing 70 composition including a heat-softenable and then hardenable ingredient, as, for example, a

resinous ingredient or a rubber compound that softens under heating and then hardens by vulcanization. As an example of the resinous ingredient, there may be used rosin, a rosin size, ester gum (the substantially neutral reaction 5 product of glycerlne and rosin) or dammar resin, suitably in the presence of admixed alum or other multivalent me compound adapted to form an insoluble salt 1 th the acidic component of a resin such as rosin or dammar. The resinous ingredient is preferably fusible at the temperature of the surface of the ironing roll or rolls and miscible (soluble) with the fusible material of the size in the wall board, is maintained in molten condition while the coating composition is being smoothed, and then is hardened. When the said ingredient and material are miscible, these agents will be integral at their positions of intimate contact in-the finished product, the surfacing composition being thus firmly secured to the sizing material of the wall board.

In the product made as described, the coating composition conceals all the fuzziness and porosity of surface that would otherwise be apparent, is practically smooth on its exposed surface, and, because of the thickness and attendant stiffness of the base sheet, maintains its planeness of surface. Furthermore, paint applied over the surfacing composition does not sink into the base sheet, the film of surfacing composition constituting a barrier to the penetration of paint into the wall board. Less paint is therefore required than would be the case if the sheet were not surfaced. Also, the paint coating is particularly smooth when applied over the surfacing 36 composition and allowed to in a usual manner.

The details given are for the purpose of illustration, not restriction, and variations made within the spirit of the invention are intended 40 to be included in the scope of the appended claims.

What I claim is:

1. The method of treating a dry, thick, and resiliently compressible insulating wall board sheet composed of felted and adhesively bonded fibres which comprises applying moisture to the thick sheet followed by smoothing and ironing of the moist sheet, rolling a layer of a fluid surfacing composltion, including an adhesive, a finely divided solid filler material and a volatile extender, on said wall board, in excess of that required to close and extend over the irregularities of the surface, while compressing the coated sheet to momentarily reduce the thickness of the coated sheet, allowing the compressed sheet to reexpand while the applied composition is still fluid to permit part of said composition to be drawn into the interior of the sheet and subsequently contacting the coated sheet with smooth and heated ironing means adapted to smooth and heat the outer surface of the applied composition, thereby eliminating the volatile extender and producing a smooth hard coating.

2. The method of treating a dry, thick', and resiliently compressible insulating wall board sheet composed of felted and adhesively bonded fibres, as described in claim 1, in which said ironing means is heated above 500 F.

JOHN a. WIENER.