US1999243A

US1999243A - Veneered products

Info

Publication number: US1999243A
Application number: US449116A
Authority: US
Inventors: Emil C Loetscher
Original assignee: Individual
Current assignee: Individual
Priority date: 1930-05-02
Filing date: 1930-05-02
Publication date: 1935-04-30
Anticipated expiration: 1952-04-30

Description

Patented Apr. 36, i935 UNITED STATES PATENT 'OFFICE VENEERED PRODUCTS Emil C. Loetscher, Dubuque, Iowa Application Ma'y 2, 1930, seria1N0.449,116 2 Claims. (C1. y20-39) This invention relates to improvement in wood veneered products and-to processes for producing the same.

The object of the invention is to provide a veneered material suitable for panels, wood Work, furniture tops and the like, utilizing a base of composite or orous material covered with exceedingly thin sheets or layers of Wood veneer.

The art of Wood veneering is a very old one, and has been extensively practiced in the manufacture of mill work and in cabinet and furniture making. Generally speaking, wood veneer is the resulting product of the application of thin layers of relatively expensive or rare Woods over a base or core of a less expensive Wood, and while the method of veneering may vary, for .different classes .of work, it consists generally of gluing thin sheets of the veneer to a core, which may be several plies of soft wood, as in the case of a panel, a piece of solid Wood or made up of small blocks or strips of wood assembled and glued together. The thickness of the veneer may vary from'slf to 1A; of an inch, and Whenthe piece or article has been made, the surface is finished in the same manner as though of solid Wood, that is, varnished and rubbed down to produce a smooth polished surface.

The present process of wood Veneering and the resulting product diers from the usual practice in several marked respects: In the first place, the base of the material is a prepared brous substance such as compressed oornstalk ber or any one of several processed building materials of a cellulose fibrous composition having a density comparable to that of a soft Wood, and While there is considerable choice as to the base material that can be used, they have one property in common, namely, that they are compressible in some degree during the process/'of manufacture. Secondly, the veneering material is considerably thinner than is ordinarily used for the purpose, namely, from 1/50 to 1/128 of an inch, that is, of a thickness approaching that of paper, but well within the range of commercial production. Now, it would be quite impossible to use paper-thin Veneer in the manufacture of veneered products by the usual methods, inasmuch as it cannot be glued to a core without wrinkling and splitting and, furthermore, any unevenness or imperfections in the surface of the base material would be readily visible through the thin `sheets of veneer. Consequently any attempt to reduce the thickness of the veneer is a decided detriment to the production of a satisfactory product by ordinary methods.

However, by the process now to be described, it is possible to manufacture veneered products which are comparable with, and in many respects superior to,v ordinary wood veneering in 5 the manufacture of mill products, furniture and cabinet work generally.

For the 'purpose of illustration, the accompanying drawing discloses a table top made in accordance with the invention, and accord- 10 ingly Figure l is a perspective view of a corner section of the table top, and

Figure 2 is an enlarged section through the edge of the table top as taken on line 2 2 of Figure l.

According to the improved process, the base or core l of the article, as already stated, is of a fibrous composition formed from cornstalk or other cellulose 4pulp compressed to the required 20 thickness and density, and cut or moulded to size, although for products such as panels, commercial board of a fibrous composition may be used. Having prepared the brous material for the base, it is treated to receive the veneer by 25 first coating its surfaces With a resinous varnish, and then drying it in an oven or drying room to drive off the solvent. Bakelite varnish is preferably used throughout the process on account of its general superiority over other 30 resinous substances, and particularly as a heatresistant and moisture-repellent, although less expensive natural resin varnishes may be used.

Over the exposed surfaces of the core are the thin sheets of

Veneer

2, 2 which may be any 35 kind of hard Wood, such as Walnut or mahogany of, say, l/80 of an inch in thickness, or about that of a sheet of paper. These sheets of veneer are prepared for use by treating them with a Varnish, that is, a resinous substance dissolved 40 in a hydrocarbon solvent such as alcohol, a solution of bakelite being preferred for the reasons already stated. Due to the thinness of the sheets they become thoroughly saturated, and when dried in an oven or drying room, the solvent is 45 driven off, leaving the sheets thoroughly impregnated with the resin or bakelite, as the case may be.

The sheets of veneer thus treated are laid over the surfaces of the core, and the process com- 50 pleted by subjecting the assembled materials to pressure and heatin an especially equipped hydraulic press and between die plates having smooth polished surfaces. The platens ofthe press have suitable connections for circulating steam and water therethrough, while the die plates conform to the contour of the finished article. Having placed the material in the press and steam is admitted to the platens until the temperature has been raised to fusing point of the bakelite, say, 250 C., whereupon the pressure is increased to, say, from 200 to 1000 pounds per square inch, depending on the density to which the panel is to be compressed. After this pressure and heat have been maintained for the required period of time, varying from 5 to 15 minutes, the temperature is reduced to normal by circulating water through the platens and then the pressure is relieved and the finished article removed from the press.

Now, the effect of the combined pressure and heat is the reduction of the core to its final thickness and density, the pressing of the veneer smoothly and evenly over the surface and edges of the core, and finally the fusing of the bakelite which, when cooled, forms a hard and indestructible coating or layer, which not only impregnates the sheets of veneer, but permeates the surface of the core and forms a colorless, protective surface nlm that is impervious to moisture, fireresisting and capable of withstanding hard usage. Due to the careful preparation of the plates in contact with the surfaces of the panels, no further treatment is necessary. In fact, any desired nish may be obtained from dull to glossy, depending on the extent to which the surfaces of the plates are polished.

The results thus obtainable are attributable in a large degree to the resiliency of the base material, which makes it possible to produce the smooth finished surfaces which require no subsequent treatment or finishing. Furthermore, in applying the thin sheets of veneer to a somewhat resilient base material, no great degree of care need be taken in applying the thin sheets of veneer, where two or more are required to cover the surface, inasmuch as their edges may overlap, and the base will yield suiciently to compensate for the extra thickness, so that no trace of unevenness appears on the surface. This suggests another advantage of the present process, namely, in the ornamentation of the surfaces by before any considerable pressure is applied,`

the addition of inlay designs, shown as a strip 3, parallel to the edge. Thus instead of the tedious process of cutting and fitting the inlay strips into grooves formed in the veneer, as in the ordinary practice, it is only necessary to cut out the inlay design from a sheet of the thin bakelized wood veneer and lay it upon the over-all veneer and in the subsequent pressure treatment the inlay will be pressed into surface without revealing any surface unevenness as shown in Figure 2.

And finally it is to be noted that by the present process it is possible to carry the veneering over and around irregular surfaces and edges, such as the moulded edge of a table top as illustrated. This is possible, both because of the yielding nature of the-base material and the extreme thinness of the bakelized veneer sheets, which conform readily to irregularities in the surface contour without breaking or the fibers separating.

As before stated, the present invention applies to all kinds of veneered products from a plain panel to highly ornamented articles of furniture, and, therefore, it is not limited to the specific disclosure either as to the process employed or the resulting product.

Having set forth a preferred embodiment of my invention,

I claim:

l. A composite veneered material comprising a relatively thick base of a fibrous material capable of being compressed to a predetermined uniform thickness and density, and a surface layer of thin wood veneer impregnated with a resinous substance adhering the veneer to the surface of said base and providing a hard surface film.

-2. A composite veneered material comprisinga relatively thick base of brous material capable of being compressed ,to a predetermined thickness and surface contour, paper-thin sheets of natural wood veneer impregnated with a synthetic resin adhering to the surface of said base and providing a hard over-all surface finish therefor, and an inlay of similar veneer applied over said surface veneer and impressed into said base flush with the surface of said veneer.

EMIL C. LOETSCHER.