US1903342A - Process for coating and sealing red cedar lumber to prevent the escape of cedar aroma - Google Patents

Description

Patented Apr. 4, 1933 UNITED STATES,

PATENT OFFICE FRANK BABAK, 0] WASHINGTON, DISTRICT OF COLUMBIA, DEDICATED TO THE AND THE PEOPLE OF THE UNITED STATES OF AMERICA PROCESS FOR COATING AND SEALING RED CEDAR LUMBER TO PREVENT THE ESCAPE OI CEDAR AROMA No Drawing.

Application filed August 2, 1930. Serial No. 472,742.

(enman wanna 'ma ACT or Manon a, less, asv manner man. 30, 1928; 370 o. e. as?

scribed to the free use of the public to take effect upon the granting of a patent to me.

The use of cedar, particularly red cedar,

) for the manufacture of containers for clothing, particularly cedar chests and cedar closets in homes, has come to be quite extensive because of the efficacy of the aroma in preventing moths from inhabiting and destroying or injuring articles of clothing stored in such containers. Because of the comparative scarcity of red cedar and the consequent cost of same, closets and chests for the purpose stated are now commonly lined with the red cedar wood and the manufacture and sale of cedar closet lining has come to be an industry of considerable proportions in this country. The red cedar is out. into boards or strips ofappropriate thickness and with, say approximately in thickness by 2 in width with the edges formed to be interengaged by tongue-and-groove formation. The eflicienc of the red cedar for the purpose mentioned maximum concentration of cedar aroma or vapor within the closet or chest. The aroma or vapor from the cedar is produced by volatilizati'on' of the emential oil contained in the wood. As the result of experiments extending over a considerable period of time, I, have discovered that when cedar' boards are exposed to the air there is a loss of oil by vola- 40 tilization, which loss is proportionate to the thicknessof the boards and the length'of time exposed. Cedar boards exhale aroma and thereby lose oil from all exposed surfaces As will be readily understood the aroma exhaled from the exterior surface of the board is lost. In order to conserve the volatile oil it is important that loss from such exterior surfaces'be revented. In cedar chests this is sometimes 1n a measureaccom plished by the finishing coating on the exterior of the cedar. In cedar closets, how

is dependent upon the ever, which are constructed by boarding up the side Walls and ceiling with the cedar boards attached directly to the studs and joists such loss from the exterior surfaces is material and all waste, with the resulting efliciency of the closet for-the purposesintended greatly depreciated.

Since the cedar boards exhale aroma from all exposed surfaces it will be readily understood that the exterior surface gives off the aroma in the same, volume as the interior surface: The aroma-volatilized from the exterior of the boards is practically lost to the interior of the closet. For "the purpose of conserving the aroma and prolonging the efficiency of the closet, chest or other container lined with the cedar, these experiments have been conducted to discovera material method of application. In planning the pro:

cedure for the experiments several important points were regarded as entitled to particular consideration as follows: 1) Effective sealing of the exterior to prevent any escape of oil (cedar aroma) in that direction. 7

(2) A coating that would be transparent and with no covering power in order that it could be observed by a glance that the boards were'of red heart wood only, the type of wood recognized as most eflicient for the purpose. (3) A coating that should permit of easy application and dry quickly and permanently.

(4) Acoating that after being applied to the boards should be free from all stickiness or tackiness in order that the boards might be packed in bundles without adhering to each other, as in making up packages for shipment and handling as -an article of commence. l I

(5) Low cost of the material and of the application of the same to the boards.

order to effectively seal the wood toit should combine transparency and rapid drying qualities, lack of stickiness and low cost.

The following materials have been used in my experiments:

Orange sheZZac.-A varnish pre ared by dissolving orange shellac in enatured alcohol. A commercial product obtainable in the open market.

Lacquer (clear).Obtainable in the market as brushing lacquers (clear).

Floor varnish (4 hr.).A special type of floor varnish which dries to extreme hardness in four hours; obtainable on the market.

Pamyfin (M. P. 55 0.) .Prepared by dissolving three pounds of paraflin in one gallon of an appropriate vehicle, as for example, carbon tetrachloride or gasoline.

Gal m ambia-A 20 per cent solution of commercial powdered gum arabic in water.

Gelatin-A 10 per cent solution of commercial crude gelatin in water.

Water-glass (sodium siZz'cate).Oommercial sirupy water-glass diluted in the proportion of 250 parts of water-glass to 25 parts of water.

For use in making the desired tests, miniature tight cedar closets, or boxes (4: in. by 8 in. by 12 in.) with a hinged lid, were constructed of inch red cedar heart wood. The coatings were applied to the exterior of the boxes as uniformly as possible by means of a flat varnish brush. The coated boxes together with an uncoated box as a check were set aside and kept in a warm room for a period of several months, after which a careful examination of each was made.

Examination of the boxes after such exposure at temperatures between 70 and 90 F. showed that all the coatings effectively sealed the wood and prevented the escape of the cedar oil, no odor of cedar being perceptible on the outside of the boxes. The interior of the boxes had an unusually strong odor of cedar. The check box with no coating had a distinct odor of cedar which indicated that the wood was still exhaling odor into the atmosphere.

Since the appearance of the Wood after the application of the coatings has an important bearing on the practicability of the various materials used, a careful analysis of the appearance in each instance was made.

The box coated with paraflin seemed the most natural in appearance, the red color of the cedar apparently being unchanged; also there was a total absence of gloss.

The boxes coated with gum arabic and gelatine, respectively, were also practically unchanged in color but both were slightly glossy.

The lacquer-coated box preserved the original red color to a marked degree with only very slight gloss apparent.

Orange shellac slightly intensified the red ous solutions, dried by evaporation of themoisture in from 1 to 2 hours.

An approximate estimate of the cost of these materials was made, based on the current'wholesale price of the materials used. The cost of application was not estimated because of the fact that by mechanical means, such as would be used on a factory scale, it would be considerably less than application by hand.

Parafiin, lacquer, orange shellac and floor varnish are most effectively and economically applied by spraying or atomizing, while the other coatings could probably be less satisfactorily applied in this manner.

From the experiments with these materials extending over a period of time, I have'selected paraffin as the coating especially desirable for the purpose. While I advocate the use of paraflin I do not wish to be restricted to its use alone. Paraflin has the advantage over other materials because of its low cost, and the desirable feature of efl'ectiveness, quick drying and non-sticky qualities, without changing, obscuring or hiding the color of the originalwood.

The non-sticky quality. of the coating is very important because of the fact that the boards are put up for sale in packages of practically airtight character and oftentimes remain in these packages for many months. Under these circumstances many of the coatings which otherwise would be reasonably practicable become impracticable on account of their tendency to become sticky and cause the boards to stick together in the package,

injuring or destroying their value for the purposes for which they are designed. When dissolved in carbon tetrachloride the hazard in its application due to inflammability is ever," should be more than offset by the superior quality and effectiveness of the cedar lining for the purpose. p

Having thus fully described my said invention, what I claim as new and desire-to secure by Letters Patent, is: 1. A liningfor containers such as closets and chests consisting of cedar boards one surface of which is coated with a transparent sealing substance comprising paraflin which substance is adapted to seal the pores of the wood a ainst the escape of the volatile oil or aroma ut at the same time leave the wood surface exposed to view, and the other surface of which is left uncoated whereby the volatile oil or aroma of the cedar may escape freely into the interior of containers lined therewith. 2. A closed receptacle lined with cedar boards the face of the lining boards next to 2 the walls of the receptacle being coated with a transparent non-adhesive sealing substance comprising paraffin to vprevent the escape through such side of the volatile oils or aroma of the cedar, and the inner face'of such lining '25 boards being left uncoa'tedwhereb'y the volatile oil or aroma of the cedar may escape freely into the interior of the receptacle.

. FRANK RABAK.