US1909795A - Coated cellulosic plastic - Google Patents

Description

May 16, 1933. B. ANDERsEN ET A1.4

GOA'ED CELLULOS IC PLASTIC Filed Jan. 25, 1,950

ATTORNEYS Patented May 16, i 1933 UNITED" s'rxrssy BJORN ANDERSEN, OF NEWARK, AND CARSTEN LYNG, F BAYONNE, NEW' JERSEY, ASSIGNORS T0 CELLULOID CORPORATION, A CORPORATION 0F NEW JERSEY COATED CELLULOSIC PLASTIC This invention pertains to the general class-of cellulosic plastics and particularly to cellulosic plastics coated with metallic substances.

This invention pertains more-particularly to the coating of thermoplastics by means of electrolytically deposited metallic substances, an object of the invention being the employment of a thermoplastic as a base to support a` .film of any desired thickness of any suitable metal or alloy.

A further object of the invention is'the production of articles of low cost, of llght weight, and havingl metallic surfaces for dec` orative as well as other purposes.

A further object of our invention is to provide means for coating cellulosic plastics that is simple in operation, highly efficient, economical Ain use, and otherwise highly satisfactory for its intended purpose.`

Further objects and advantages will become apparent to persons skilled in the art as the specification proceeds. i

Our invention comprises coating cellulosic plastic articles with metals by electr olyt1c means. `In carrying out our invention a cathode is formed upon the article by means of a suitable substance capable of conducting an electric current such as platers graphite, sprayed metal etc. Any portions to be left uncoated are, of course, not covered with the conducting substance which forms the cathode, and such 'portions are preferably coated with a substance which is inert in the particular electrolyte used, and which does not react to electroplating operations. WaXes are very suitable for this purpose.

In the event that the surface to be coated is not of such ay configuration as to securely anchor the coating of. metal in place, other means for anchoring the deposited metal may be resorted to such as securing anchoring plugs or surfaces of metal in or on the surface of the cellulosic plastic, .orl forming a depression of the desired configuration in the surface of the cellulosic plastic and providing metallic anchoring means in such depression, or forming the borders of such depression with a bezel ofunder-cut groove, or

any othermeans may be resorted to for anchoring the deposited coating in place.

Referring 'to the drawing wherein like reference characters are appended to like parts in the various figures,

Figure l is a perspective view of a fountain pen having the cap removed therefrom.

' Figure 2 is an elevation partly in section of a fountain pen body and cap.

Figure 3 is an elevation illustrating means for making electric contact with the cathode.

Figure 4 is a plan View of a 'fountain pen cap in enlarged scale.

Figure 5 is a sections on line 5-5 of Figure 4. v

Referring to Figures 1 and 2, at l is shown a fountain pen body adapted to receive a cap 2. 'The body l and cap 2 are made up of base 3 and base 4. respectively, and coating 5 and coating 6 respectively. Base 3 and base 4 are formed of cellulosic plastic and may be made by any means known in the art of fountain pen manufacture. After having been given the desired surface con.- tour and configuration, base and base 4 are coated with a cathode forming substance such as platers graphite or sprayedmetal. The cathode may be applied directly to the surface of the cellulosic plastic. However,

in most instances, we prefer to first coat the4 cellulosic plastic with asubstance inert in the electrolyte used, and which does lnot react to electroplating operations, such as wax,

and then apply the cathode form-ing material thereto. We find parafiin very suitable for this purpose. This procedure is particularly preferred in those instances Where the electrolyte and/or the electroplating operations tend to attack the surface of the cellulosic plastic. f

At 7 in Figure 3 is shown one Way of making contact with the cathode formed on the` outer surface of the fountain pen barrel 1 and comprises a strip of foil Wrapped aboutthe upper end of the barrel and over the cathode. i Electrical Contact with the foil 7, can be readily made by means of the terminal 7. This particular means ofcontacting the cathode is particularly useful in those cases in which the threads have already been formed, inasmuch as no metal is deposited on the part of the pen covered by the foil.

We prefer to form the cathode by first rou hcning the surface of the cellulosic plastic `y any means such as with an abrasive. Emery cloth is very useful for this purpose. Solid paraffin wax is then applied and worked thoroughly into the roughened parts. For this purpose the wax is preferably semisoft. We find that the temperature of the hand is sufficient for this purpose and that the Wax may be applied with the fingers. It is of course, understood, that any suitable tool which may be warmed if desired may he used for this purpose. Any excess wax may be removed by any means, such as rubbing with a felt cloth. Y

The platers graphite is now applied pref'- crably while the wax is in a softened condition, such that the graphite particles will readily be bound to it. paraflin Wax, a temperature of approximately 30 C. is very useful for this purpose. The graphite may be applied to the wax by any means such as with a dry brush, etc. After the cathode is formed, electric contact may he made with same by any desired means.

Many devices for this purpose will readily suggest themselves to persons skilled lin the art and familiar with our invention.

Portions'which are not to be plated may be coated with the electrolytically inert material only.

Contact is' made with the electric circuit by means of a clamp or other attachable means such as metall foil, etc. and each article kis lows preferably separately submerged inthe electrolyte. It is,`of course, obviou's that a plu- -rality of articles may be submerged at one time. However, we prefer to separatel connect each individual cathode to the e ectric circuit. For this .purpose a blockv of electrolytically inert material, having a lurality of suitable clamps may be provi ed.

After the desired coating of metal or desired order of different metals have been deposited, the article or articles are withdrawn from the electrolyte, are preferably washed in water or other liquid to remove the film 'of electrolyte, .and may then be polished or otherwise processed as desired. 4

Because of its low cost and its vready adaptability to electroplating operations, we m many instances, prefer to start plating with .copper and then end up with some metal such as nickel, silver, gold, platinum orother precious metal{ alloys of the precious metals, etc.

' Fountain pens having an -average diameter of 1.2 cm. and anapproximate length l of 9 cm. with surfaces of approximately 32 square centimeters have been plated as fol- Afterappl ing v.the wax-and the formation yof the catho e, the' pens were placed in the We find that for cellulosic plastic.

electrolyte and plating was started with the low current of about 0.1 amperes. After the copper had started tofspread over an area of about l to 1 square centimeter, the eur- -rent was raised to about 0.2 to 0.25 amper-es.

silver, gold, platinum, etc. 'lhe (,foating of.

precious metal, of course, may be of any desired thickness. The finished article may be processed by any means such as bufiing, polishing, etc.- Care must be taken, however, to avoid undue expansion of the base, due to change in temperature, particularly in those cases in which the coating is relatively thin in order to avoid cracking .of same. Before the second metal is applied, the-surface ol' the first' metal is preferably cleaned and buffed.

In Figures 4 and 5 is shown a means Awhereby. electrolytical-ly deposited coatings may be anchored to cellulosic plastics. Such anchoring is desired in those cases in which the configuration ofa'coating isnot such as to bind itself firmly to the article. At 8 is' shown the top o f a fountain pen considerably enlarged. 9 is a depression of any desired depth which it is desired to fill, under-fill or over-fill with a vmetal or metals. The de pression, merely/for thepurposes of llustration, isv in the form of the letter L and may be provlded with a bezel or under-cut groove, not shown, around its borders. yTo

eposit metal in the depression 9 it is merely necessary to coat the-same with a cathode formin substance which may be applied either -irectly to the cellulosic plastic or to the surface of an electrolytically inert substance such as wax on t e surface of the coated are preferably coated with an electrolytically inert substance. Contact with the electric circuit may be made `with any suitable means such as a metallic -rod not shown,

All surfaces .not to be inserted .in the cap-and contacting'the anchoring means. The article is'then dipped in the electrolyte, and any desired thickness of coating or coatings may be applied.- The surface of the deposited metal may, of course, bebelow', above or flush with the surface of the article as desired.

In Figure 4 is shownsuitable anchored means; The depression 9`has side walls 10 which may o r maynot be under-cut. Ani choringlugs 11 of a suitable metal are secure- 1y set 1n the fioor of the depression 9. Stemsl 13 on lugs 11v may project slightly beyond ert material. The lugsll, however,

the' vinner wall 14 of the om 2. Sicient space, however, should be owed for free movement of the pen point. The upper sur-l faces.t of the lugs `11 are, of course, exposed andare not coated with either the cathode forming substance or the electrolytically inare made a part of the cathode. This is accom lished by bringing the cathode forming su u to and 1n contact with the edges thereof.

e lrst coating is thus firmly unitedto the lugs 11, which m turn .are anchored to the lace. f P While this invention has been described as being ap lied to a fountain n, it is of course, o vious that the con guration or nature of the article itself is immaterial, and

' that the invention may be applied to cellu- .a substance or substa methyl phthalate, diethyl phthalate,

A without departing tain pen comprising a base-of cellulose nitrate losic plastic articles without limit.

By lthe term cellulosic plastics is meant plastics made with cellulose nitrate, cellulose acetate, cellulose formate, cellulose propionate, cellulose butyrate, methyl cellulose,

ethyl cellulose, benzyl cellulose, celulose phthalate, etc. Of these, the vplastics made with cellulose nitrate are preferred. The

.article and the metal is thus firmly held in v formation of-plastics with these materials is well known in the art and is nerally accomplished by means of the ad 'tion of nces commonly referred to as plasticizers. Camphor .di-

dihutyl phthalate, dibutyl tartrate, paraethyltoluolsulphonamid,

ph hate, mono methyl exylene s ami areexamples vThe submances are by the aid of a volatile solvent as is well known, as well as the further pr necessa to bring these lastics into a con suita le for the manu acture of articles.

Having described our invention it is obvious that many modifications may be made in the same within the sco of the claims fromt e spirit ,of the invention. v.

We claim: 1. As a new article of manufacture, a fountain'pen comprising a base of'cellulosicv plastic having a coating of electrolytically deposited metal anchored to the surface thereof.

2. As a new article of manufacture, a founplastic having a coating of electrol icall deposited metal anchored to' the silrfac theref.

In testimony whereof, wehave hereunto subscribed our names.

BJoBN ANDERSEN. -cansTEN mme'.l

generally combined methyl salicylate, triphenylV phosphate, tricresyl phosphate, trinalphthyl phonition I

Images