US2158907A - Method of producing veneered products - Google Patents

Description

Patented May 16, 1939 UNITED STATES PATENT OFFICE amber METHOD or raonucmo vamarn mono Lawrence Ottinger, New York, N. Y., assignor to United States Plywood Corporation, New York,

N. Y., a corporation of New York Application February 9, 1931, Serial No. man: i

1 Claim.

n commonly termed coniferous", such as Oregon fir, yellow pine, etc., without having the hard and soft grain of the summer and spring growth show through the imposed veneer layer when the veneer is shellacked, varnished or lacquered. The refraction which obtains under the conditions just mentioned destroys the character of the veneer surface and as a consequence such soft coniferous woods have not been employed in the production of high grade veneered products.

I havediscovered that by a simple pre-processing of a core or body element of coniferous wood, the same may be utilized in con unction with a thin veneer to produce a veneered element comparable with one wherein a core of hard wood, such as birch and poplar, or one where the grain of a soft wood employed as the core or body element was masked by a sheet of hardwood interposed between the veneer and. the body. of course, veneers say of 15" or thicker, have been successfully applied to pines where the veneer is thick enough to eliminate the showing of the grain lines. A veneer of such thickness is, of course, expensive as compared to one of A or thereabouts and is not commonly employed.

In the annexed drawing, which is more or less diagrammatic, .I have sought to illustrate in a general way the steps employed in carrying out the process of my invention, and wherein:

' Figure 1' is a sectional view of a panel comprising three plies and the platens of a hot press;

Fig. 2, a sectional view of the pro-compressed core with an adhesive applied to that surface to which the thin veneer is to be applied;

Fig. 3, a like view with the veneer imposed on the adhesive treated surface; and

Fig. 4, a sectional view similar to Fig. 1, illus-.

' trative of the final compression step to ensure adhesion of the veneer.

In producing a body or core upon and to which the thin veneer is to be applied and secured, I.

take a piece of coniferous wood or a plywood panel formed of such material and place the same in a hot plate press.

In the drawing; 1, have illustrated -tlu"ee ad- 56 jacent plies, I, 2 and 3 ,which for the sake of brevity will be hereinafter referred to as a core or body. These plies are subjected to heavy pressure between platens 4 and 5 of the hot plate press. Such heat and pressure have the effect of bringing the hard and soft portions of the grain 5 of the surfaces which are in direct contactwith the hot platens into a smooth common plane. In other words, the aggregated tougher portions of the vascular bundles and the intersecting medullary or vascular rays, which constitute the so- 10 called silver grain, are displaced and as above noted, are brought or carried into a common plane. At the same time, any contained moisture is eliminated.

To the flat surface thus produced, a suitable 15 adhesive 6 is applied, said adhesive sealing the surface of the coniferous ply. Resin adhesive, casein or other glues in dry form, either dry per se or originally wet and allowed to dry may be utilized. So, too, any thermoplastic adhesive, in- 20 cludingthose produced by using rubber or latex alone or in combination with other materials or cellulose acetate, either in liquid or sheet form, may be employed.

Upon the surface thus formed and to which the 25 adhesive has been applied, I apply the desired veneer, as 1. Such veneerwill be caused to adhere by the action of pressure or the conjoint action of pressure-and heat, if the adhesive is of the thermoplastic type. 30

By the method above set forth, one is enabled to employ coniferous wood as the body or core piece of a veneered product employing'thin veneer of hardwood which will not be deformed and which will not, when it is finished as above speci- 35 fled, show the underlying grain of the coniferous body.

The article described herein is claimed in my copending application Serial No. 243,471, fll December 1, i938. 40

What I claim is:

That method of making a wood veneer struc-= ture employing a coniferous core piece characterized by the presence of contrasting spring and summer growths and in'which the grain of the 46 core piece is entirely obscured by .the veneer, which method consists in subjecting the core piece to the direct action of heat and compacting pressure to bring all exposed portions of the grain of the core piece into a common plane, and thereafter imposing uponand securing directly to such treated surface a hardwood veneer having a thickness not substantially exceeding ,5

. 'IAWRENCE o'rrmoaa. u

Images