US2315713A - Molded article, binder, and process of manufacturing the same - Google Patents

Description

April 6, 1943.

F. .1 ...xoHNsoN 2,315,713

MOLDED ARTICLE, BINDER, AND PROCESS OF MANUFACTURING THE SAME Filed June 18, 1940 Patented Apr. 6, 1943 MOLDED ARTICLE, BINDER, PROCESS OF MANUFACTURING THE SALIE Fred J. Johnson, Rockville Centre, N. Y. Application June 18, 1940, Serial No. 341,101

(Cl. 1847.5)v

16 Claims.

My invention relates to the manufacture of.

molded articles including the process for the manufacture thereof, and the new and particularly advantageous binder employed in such manufacture, and the said invention is fully disclosed in the following description and claims, taken in connection with the accompanying drawing.

My invention is based on a discovery that, by combining or admixing water glass (an aqueous solution of sodium silicate) together with a stearate, preferably zinc or other metallic stearate, an extremely desirable binding material results, to which may be added a wide variety of filling materials, thereby obtaining a variety of new and unexpected results having common characteristics, due to the presence of the binder, but varying somewhat in accordance with the filling material, or materials, employed. The resulting plastic material is molded in any desired manner and is thereafter dehydrated by air curing or by the application of heat with or Without the simultaneous application of pressure, or in any other desired manner, to deprive the material of its moisture content. My improved molded articles iind their largest use as building material in the forms' of blocks, slabs or sheets, but as will be obvious, the material can be molded into any desired form, and as it may be made weather-proof by the selection of suitable filling material, it is adaptable for the .manufacture of statuary, garden ornaments, tomb-stones and mortuary monuments, and a wide range of other uses.

In the accompanying drawing,

Fig.v 1 illustrates a building block embodying my invention, and presenting a substantially dense and uniform character due to molding and air curing orldrying.

Fig. 2 represents the application of my invention to the formation of sheets or slabs of the composite material and illustrates one method by which the application of heat for drying or dehydrating the samel may be carried out.

Fig. 3 is a sectional view oi. a mold within which a block-of the material may be held under pressure during dehydration, which in this instance is effected by means of a hollow core to which a heated medium is continuously supplied.

Fig. 4 represents a different form of mold having hollow walls supplied with a circulating heating medium and e'ecting the expansion of the entire molded mass during the dehydration thereof.

Fig. 5 is a sectional view of a somewhat similar Y found the following proportions tol give satisfacterial ls molded to the tory results, to wit:

Parts by volume Solution of sodium silicate in water 4 Zinc stearate 1 These ingredients are mixed and brought to a creamy consistency. To this mixture is added any one or more of a large number of bulk material or filling material, preferably in sumcient quantity to bring the plastic material to the consistency of bread dough, a porous consistency analogous thereto being produced by the frothy consistency of the binder mixture. This frothy condition of the binder is somewhat reduced by the addition of the filler. but may be again increased by the application of heat. The actual amount of filling material may be'varied to a considerable degree in accordance with the results desired.

For the formation of blocks, sheets, slabs, etc., for use as building material, I have found suitable fillers to be asbestos, ground or crushed slate, marble d ust, rock wool, glass wool, sand, sawdust, paper or paper pulp, ground seashell, and many other similar materials, inert or otherwise, or various combinations of two ormore of these materials, according to the characteristics of the blocks -or sheets desired and the use to which they are to be put.

For other uses, such as Statuary, urns, garden ornaments and mortuary monuments, I have found that by adding to the above base, marble dust, ground slate, ground seashell and other like materials, very satisfactory products of good appearance are obtained with satisfactory resistance to atmospheric conditions.

After mixing the selected filling material, or materials, with the binder and bringing the same substantially to the consistency of bread dough, for example, the plastic material is dehydrated in one of many way For example, in the pro.- duction of building blocks, the dough-like madesired form as illustrated in Fig. 1 by the block l, said blocks may be dehydrated by subjectlng them to the action of makes a very light .ing purposes, which can dough-like plastic,

size of the block may be accurately reached in the iinal article, secondly, a smooth, uniform` and substantially impervious surface may be formed on the exterior of the molded article, and

thirdly, the relative density of the finished article may be controlled by the relative amount of plastic material chargedinto a mold of given size, as well as by the consistency of the mixture.

In Fig. 3, for exampleI have illustrated the mold at 2, having a central core 3, which can be continuously supplied with a heat medium, as steam heat, by means of pipes 4, 4. The plastic mass is charged into the mold and surrounds the core 3. On the application of heat to the core, the moisture within the mass will be driven outwardly and the plastic mass will be compressed by the vaporized water as well as by the frothing of the binder mixture, against the outer surface of the mold where the greatest density.

of the block will naturally exist as the dehydration progresses, and as indicated in the drawing, in which the block is shown at 5. It will b understood that the mold, while tight enough to confine the block, will permit the moisture during the application of heat.

The advantages of dehydrating the plastic mass in the mold will be readily understood, as the exterior faces of the finished dried blocks willnaturally partake of the character of the inner faces of the mold, and these maybe varied to any desired extent. For example, the blocks may be formed of an exterior surface resembling stone where they are to be used inthe wall ofy a building, while the inner surface may be smooth and polished or decorated in any desired designs provided on the inner face of the moldf'in accordance with the desire of the manufacturer, thus making a light and strong building-block which could be used if desired without further treatment on either the outer or inner faces-of the wall in which it was used.

In Fig. 4 I have the heating medium molded block is at the exterior instead of the interior of the plastic mass. In this instance the mold 6 is provided with the hollow wall, indicated at 1, to which the heating medium, as steam or hot air, may be supplied, as byv means of pipes 8. The application of heatto the exterior ofthe block 9 necessarily vaporizes the water content of the mass and produces anexpansion of the mass outwardly towardv the inner surfaces of the mold. This, as shown in-Fig. 4. has the effect of increasing the density of .the block at the outer faces thereof, indicated-at Il), making it substantially impervious, `while the interior of the block will-be found, upon breaking it, to be nlled with voids, indicated: at block for all kindsoi buildbe manufactured in any size or shape desired, and the facesvmay also be ornamented or decorated, as previously described.

It will be seen that an economy is eifectd in that, while the mold is charged fully with the the actualamount of material for each block is considerably less than the cubimold. In actual practice it is found, however,

voids Il hereinbefore described and formed of tively connected with a escape of excess illustrated a mold in which for the dehydrationof the yprovided as shown in the plastic material, have ample strength to resist all the necessary stresses 'to which such building material will ever be subjected in normal use.

In some instances, however, it may be desirable to provide blocks of greater density, .and this can be readilyy accomplished by such means, for example, as is illustrated in Fig. 5, in which I have shown a block l2 being formed within a mold I3, having hollow walls, indicated at I4, supplied with a heating medium by pipes l5, and

Fig. 5, with means for applying continuous pressure to the block during the drying operation. In this instance I have shown a plunger I6, which is also hollow, as indicated at I1, and supplied with a heating medium by means of pipes I8, the plunger being connected with a rod I9 which may be operasuitable ram or other power applying means, so that the material, represented by the block I2, will be acted upon by the heat from the heating medium in the hollow walls and' plunger, and will at the same-time vbe continuously under the influence of pressure, so that as the moisture is driven out the `material becomes more 'and more dense, and by this means orany other suitable condensing means, the production of blocks or other molded products, which are substantially of uniform density throughout, may be obtained, while at the same time a complete uniformity of size and the character of the exterior faces of the blocks is retained.

In some instances I have found it desirable to form the dough-like material as a ilat sheet, plate or slab, which is admirable for roofing purposes, and also for floor tiles, wall tiles and many other purposes.

"may be rolled between heated surfaces.

In Fig. 2, for example, I have shown a hollow metal bed at 20, to which a heating medium, as steam or hot air, may be admitted continuously by pipes 2|, 2|, the dough-like material in such instances being spread 4on the bed 20 and rolled to the desired thickness, as indicated at 22, by means of a hollow roller 23, the interior of which is also provided continuously with a circulating heating medium, by means of suitable pipes 24, 24.

If desired,the expansion of the plastic material upon the application of heat, above referred to, may be availedf to produce novel forms from unconflned shaped sheets ofthe same, as such sheets or other portions may be partially dried by air-curing without heat and heat thereafter applied to produce a puffing of the material, by which it is obvious that a variety of ornamental articles may be made, having a predetermined outline and a form rounded* out by such expansion after '.'he hardening of the surface. For certain purposes, for instance, brickmaking etc., the mass may be mixed to a very stiff or dry powdered state and subjected to a high pressure,'with or without heat.

It will readily be seen that there is practically It will` be seen that in the selection of filling material, inert colored matter no limit to the variety and number of dinerent articles which can be manufactured by the use of my improved material, and in accordance with my improved process, and practically any desired surface texture or color or ornamentation can be obtained without materially increasing the oost of production.

What I claim and desire to secure by Letters Patent is:

1. A binder for molded articles, consisting essentially of waterglass mixed with zinc stearate and brought to a creamy consistency.

2. A molded article consisting essentially of waterglass and a metallic stearate combined with a lling material.

3. A process i'or the production of molded ar. ticles, which consists in mixing waterglass with a. metallic stearate, and bringing the mixture to a creamy consistency, adding lling material, forming the resulting mass in a mold, and treating the molded mass to dehydrate the same.

4. A process for the production of molded articles, which consists in mixing waterglass with a metallic stearate, and bringing the mixture to a creamy consistency, adding lling material, forming the resulting mass in a mold, and dehydrating the molded mass while confined in a mold.

5. A process for the production of molded articles, which consists in. mixing waterglass with ametallic stearate, and bringing the mixture to a creamy consistency, adding illling material, forming the resulting mass in a mold, applying heat to the mold to expand said mass while conned therein to force it against the mold and produce a substantially impervious exterior surface, and to simultaneously produce voids in the interior of the mass.

6. A process for the production of moldedl articles, which consists in mixing waterglass with a metallic stearate, and bringing the mixture to a creamy consistency. adding illling material, forming the resultingmassin a mold, and dehydrating the molded mass by application of heat while conned in a mold. l l

7. A process for the production of molded articles, which consists in mixing waterglass with zinc stearate and bringing the mixture tog-a creamy consistency, adding filling material, forms' ing the resulting mass in a mold, and treating the molded mass while conilned in the mold to the action of heat within the plastic mass for the de,- hydration of the same and the expansion oi' the molded material to and aaainst the walls of the 8. A process for the production of molded articles, which consists in mixing waterglass with a metallic stearate, and bringing the mixture to a creamy consistency, adding illling material, and dehydrating the molded mass by simultaneous application oi' heat and continuous pressure.

9. A process for the production of .molded articles, which consists in mixing waterglass with a metallic stearate, and bringing the mixture to a l creamy consistency. adding filling material, rolling the mass into sheet form and dehydrating the sheet material so formed.

10. A process for the production of molded articles, which consists in mixing waterglass with a metallic stearate, and bringing the mixture to a creamy consistency, adding illling material, rolling the mass into sheet form, and simultaneously applying heat to dehydrate the material.

11. A molded article composed of waterglass mixed with a metallic stearate, and lling material, and having a substantially impervious molded exterior surface,l and having its interior provided with voids.

12. A molded article composed of waterglass, mixed/with zinc stearate, and lling material, and having a smooth substantially impervious exterior surface, and having its interior provided with voids.

13. A process for the production of molded articles, which consists in mixing waterglass with a metallic stearate, bringing the mixture to a creamy consistency, adding illling material, forming the resulting mass, and dehydrating the same. Y

14. A'process for the productionof molded articles, which comprises mixing waterglass with a metallic stearate, bringing the mixture toa creamy consistency, adding filling material and bringing the mixture to a stii condition, subjecting the mass to high pressure and dehydrating the same.

15. A molded article consisting essentially of waterglass mixed with a metallic stearate, and nlling material. and having a substantially impervious exterior surface and a porous interior portion. v

16. A molded article consisting waterglass mixed with a metallic stearate, and filling material and having a substantially impervious exterior surface and a hollow interior.

FRED J. JOHNSON.

essentially of

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