US2345583A - Coated object and process for making the same - Google Patents

Description

estimated.

Patented Apr. '4, 1944 coa'rnp onssc'r ANnrnooEss FOR MAKING 'rnn SAME New'comb K. Chaney; Moylan. Pm, assignor to The United Gas Improvement Company, a cor- H poratlon of Pennsylvania I No prawns.

Application August 19, 1939, Serial No. 291,007

19 Claims. v(o1. 99 -181) application is a continuation in part of my'copendlng, application SeriallNumber 174,011,. filed November 11,,1937- This invention pertains generally to the coating o of metals. andiparticularlyl to the coating of metals in sheet form. a v t h The invention pertains more particularly to the coating. oi sheet metal which is1to be ,iabricated ing,,and the like.

Machine operations, suchas the foregoing, are particularly severe upon coatings or films adhering to the sheet metal, andin many instances, it is extremely diflicult toohtaina formed object with acoating [or system adequate for the environment to whichth'e finished article is to t be subjected when in use.

To illustrate, many'types 6r fllrn's and-particularly those made from resinous materials, crack,

check, striate, silk and/or peel ,when subjected j to the foregoing mechanical operations.

Because oi the great economical advantage of l j coatingthe sheet metalprior to the various form ging operations, the importance or a iilmor film system' whichf will withstand the various formhis operations without Another quality oi extreme importance, particularly in the case of certain uses to which the finished articlesare to be put, isthe relative insolubility'and chemical inertness' oi the minor film'system. 1 a

An outstanding example of such a use isin the food packaging iield in, which metal cans and metal foil wrappi are extensive u ed.

The term food is employed herein to mean that which is eaten or drunk or absorbed for nourishment or otherwise, and; includes not only beverages such as beer, but substances from which food is prepared, examples 01 which are coifee'beans, whether ground or not, and tea leaves.

In the case of cans, for example, economical considerations make it extremely advantageous iniury cannot be over-- can closing machine during the well known douhie-seaming can sealing operation.

- into obiects by operations which result in drawing; of the metal such as occurs in stamping,

, ,10 1 bending, die-drawing, threading, turning, punch- For instance, the die-drawing step produces in the c'an,ends not only anglesof very nearly 90 with relatively sharp bends. but also a peripheral portion which is curled back upon itself. A film or film system to be successful must withstand such and similar metal working operations without peeling or rupturing or otherwise failing in the slightest degree.

Metalcaps are used in large quantity not only on glass bottles but also on certain types of metal containers, such as those for holding beverages. In many cases, such caps are provided with threads for engaging cooperating threads upon the bottle or other container.

The operation for forming the threads in the metal caps lsextremely severe.

In the food packaging field it is, of course, ab soluteiy essential that the film or film system be not only completely insoluble and chemically inert, but also completely incapable of imparting taste or odor to the food product.

In this connection, it is a well known fact that the ordinary tin lining is unsatisfactory in the case oi certain foods of which grape juice, orange Juice, and beer are outstanding examples.

Some foods develop hydrogen sulfide upon standing which, in turn, reacts chemically with the tin lining to form tin sulfide. In case any of the iron is exposed, suchas through cracks, black iron sulfide is formed.

Furthermore, in the food packaging field, the

packaged food stuff, after sealing of the can, is

in many cases, subjected to a sterilization treatment by the application of heat. Such treatment,

by reason of the increased temperatures involved, greatly accelerates any reactions capable of taking place.

Numerous attempts have been made to find a lacquer which might be applied over or substito, apply thefllm or fllm' system to thesheet metal while in the flat. Thecanp'arts arethen cut,

shaped and Joined all'in a' manner well known in H the art. Severe stressesfare'set up duringthe fi'orming operations; particularly inthe case of thejdie-drawingiot the can" ends. The can ends are again subjected tose'verejstresses during the as by the seaming can closing operation," such tuted for the tin coating. Films made with previously known lacquers, as a rule, however, have failed tohave suflicient adhesion and cohesion to resist forming operations, or they have failed to resist reaction with foods, or they have failed in that they have imparted taste or odor to the This led to the adoption of a procedure whereby a coating composition having good bonding properties was employed as a primer coat for. a top coat having proper food resisting and'taste and odor characteristics, ofwhichthe material known commercially as "Vinylite" is an outstandchuck, seaming rolls, and cooperatingparts oi the ing example. Inturn, this presented the further lytically polymerized cyclopentadiene employed in my invention are described and claimed in copending application, Serial Number 194,523, filed March 8, 15238 by Samuel G. Trepp, and copending application Serial Number 204,786, filed April 28, 1938, by Frank J. Soday.

The following are specific examples of the preparation of the desired polymer.

In this connection, many'films and dualfilm "1 systems develop a cloudiness during the sterilization step, such cloudiness being generally referred to as blushing. The resulting discoloration is very undesirable from the standpoint of market appeal, since the average housewife looks with great disfavor upon any discoloration of the ln-'- side surface of a can when removing food therefrom.

vIt follows that any film or film system to be suitable must not only be capable of resisting blushing, but must in itself have an acceptable appearance and preferably one suggesting utmost cleanliness. v i

Since films and film systems of the character under consideration are necessarily extremely thin, the primer coat is preferably one capable of direct contact with the food stuff without chemical reaction and without imparting taste or odor thereto. Certain substances which might otherwise be satisfactory as primer coats fail because they are capable of. imparting taste and odor to foodstuffs through the top coat.

In addition to the foregoing, there are certain metals which are extremely diflicult to coat with satisfactorily adhering films or film systems of any character. Examples are zinc, zinc jplate, magnesium and magnesium alloys, such as the material known commercially as ,Dow metal. In fact, practically all previously known resinous coating compositions fail .to form a' satisfactory bond with these materials. I

In accordance with my invention, single film systems and multiple film systems having all of the above desirable properties may be produced by forming (a) said single film system, or (b)the primer coat of a multiple film system provided.

the top coat isof a satisfactory character, or (c) the top coat of a multiple film system provided the primer coat is of a satisfactory character, with a liquid coating composition having as a base cyclopentadiene which has been catalytically polymerized in a manner to impart to it desired properties, and then permitting such films of polymerized cyclopentadiene to dry with or without heat.

Generally speaking, the catalytically polymer:

ized cyclopentadiene employed in my liquid coating composition has the following properties. It is soluble in benzene, toluene, chloroform, carbon tetrachloride and high flash naphtha, and

insoluble in alcohol, acetone, ether and water.

For'the purpose of convenience in the claims, these solubility characteristics will be defined by the term benzene-soluble, though it is to be Example 1 1500 pounds of toluene were charged to a small jacketed, brine cooled kettle provided with an agitator and a brine cooled reflux condenser. 3- pounds of boron trifiuoride-diethyl ether complex were then charged, agitation was started, and the kettle was warmed ,to 35-40 C. After complete mixing, heating was discontinued and the steam in the jacket replaced with brine.

A previously prepared mixture of 525 pounds of cyclopentadiene and 500 pounds of toluene was gradually added from a mixing tank, maintained at a temperature sufliciently low to prevent the volatilization of the cyclopentadiene. The mixture is preferably below room temperature when it reaches the reaction kettle.

The rate of addition was so regulated that the contents of the reaction kettle were maintained at a temperature between'25-30 C. while circulating cooling brine through the jacket.

From 20 to 60 minutes were required for the addition of the cyclopentadiene-toluene mixture depending upon the emciency of the cooling brine: When addition was complete, the brine fiow was cut down so as to keep the temperature above.

25? C but below C. and the product was agitated for an additional 1 hours.

5 pounds of water were now added to hydrolyze the catalyst so that the fluorine might later be removed as hydrogen fluoride by the lime.

After 30 minutes further agitation, '75 pounds of milk of lime (Ca(OH)2) were added. The

. a suction filter, and the product pumped through understood that the actual presence of benzene in the solution or in the applied films is not implied. Preferably, my liquid coating composition has other distinctive properties. v.Among these properties is the ability to form a smooth, glassy, highly flexible and extensible and tenaciously adhering film upon drying with or without baking.

Methods for preparing benzene-soluble catathe filter. Any type of filter, such as a plate filter press, centrifuge, etc., might be employed.

The product was a 20% solution of the desired polymer. This solution may be used as such for application to surfaces, followed by drying in an oxygen-containing atmosphere, such as with baking after suitable evaporation of solvent, or the solution may be concentrated in a vacuum still of suitable design to give a product containing any desired higher concentrationofpolycyclopentadiene, if desired.

.In the above example, the particular temperatures chosenare more or less for expediency, but it will be noted that at no time didthe temperature exceed 100 C. or even 80 C. Constant agitationand brine cooling made it possible to prevent local overheating.

Example 2 0.30 cubic centimeter of aluminum chloridediethyl ether complex is'added to 60 grams of toluene with thorough agitation to form asuspension, emulsion or solution.

A mixture of 20 grams of cyclopentadiene and 1 h \more, as pointed outabove trate. i

An example of the formation of a single film follows:

? loosening, or otherwise I 2,345,588 hour, after which 1 cubic centimeter of water is 5 grams of a suitable filter aid are then added, a

and the mixture filtered.

A filtered solution containing 16.4 grams of polycyclopentadiene is thus obtained.

Generally speaking, any other boron trifluoride-organic solvent complex or aluminum chloride-organic solvent complex might be substituted in the aboveexamples.

In the above specific examples it will be noted that both the cyclopentadiene and the catalyst are-in diluted, form before addition. Furtherdilutedcyclopenta diene is preferably added to diluted catalyst rather than. vice versa to aflord a better control of the speed and uniformityof thereaction and of the amountof heat evolved and consequently the type of polymer produced. The reaction runs smootherand is much more easily controlled on a large scale.

The addition ofwatertohydrolyze the catalystmakes it possible not" only to completely remove the activity of the catalyst and .thus stop thereaction at any point, but also to remove the corrosive and discoloring acid constituents. of the catalyst by a suitable lyze the catalyst, although it maybe added later roducts ma be the cause of serious discoloration. The insoluble reaction products formed during the hydrolysis and neutralization remain behind on the filter leaving a highly purified filsystem in accordance with myinvention is as a 1 Y EsrampleA A 24% solution of the resinin toluene is applied to sheet metal, such as tin plate, in such quantities that the final resin film whether applied to one coat, or several coats with. or without intermediate baking, will have a desired thickness, such as, the equivalent of from 4;to 6 milligrams per square inch ofdry baking. f

The coated sheet, after suitable evaporation of solvent, is placed in an oven and heated to a temperature of 350 F. in order to insure satisfactory drying during which time the film, takesup oxygen from the air without loss of adhesion, fiexibilty or extensibillty. A suitable baking time is between onequarter of an hour and one and a half hours. The elevated temperatures employed favor the adding on of oxygen.

Sheet metal thus coated is ready for the most drastic forming operations, such as encountered in the manufacture of cans or other containers, bottle caps, screw caps, and the like- It will alkali. Thealkali is preferably added with the water 'used to hydrofilm after for a period of minutes.

A tin plated sheet, or other metal sheet, is

' coated with a solution of my resin in toluene, say

of concentration, in sufilcient quantity to f secure a desiredfinal coating weight, say of apbaking.

proximately 3 milligrams'per square inch after The coated sheet after suitable evaporation of solvent is placed in an oven andbaked at a temperature of say 250 V F. for a period of 15 minutes, the polycyclopentadiene adding on oxygen from the atmosphere during the baking.

Upon cooling, 2. solution of Vinylite in a mixture of higher boiling ketones is applied in suflioient quantity such that the dual film system will have a desired thickness after drying of the Vinylite filmlsuch as with baking, say a thickness equivlaent to"4' to 6 milligrams per dry dual ,film. a

.The coated sheet after suitable evaporation of solvent is then rebaked in the same manner as with theprimer coat.

It will be understood, of course, that broadly speaking, the top coat is not limitedto Vinyl- I ite, which is the co-polyrner of vinyl acetate and vinyl-chloride, but may be a polymer of any ,Of the vinyl compounds used as raw materials -vinylchloride or vinyl for the several vinyl resins; e. -.g.,1vinyl acetate, chloracetate. In fact other types of resins may, beadapted, for application as the top coat over my catalytically polymerlzed cyclopentadiene resin.

Vinyl resins suitable for use in forming the top coat of my inventionmay be formed from vinyl esters by known polymerization processes. The

co-polymerization of polymerization products of inorganic vinyl esters, such as vinyl halides, or those of organic vinyl esters, such as vinyl esters of aliphatic acids, may be used. l

I prefer to use vinyl resins resulting from the two, or more vinyl esters. For example, vinyl resinshaving desirable properties may be prepared by of a vinyl halide and a vinyl ester of an aliphatic acid. a l

Products of the copolymerization of vinyl chloride and vinyl acetate'in proportions ranging from about 10% to 90% by weight of the chloride are particularly desirable.

The commercial product sold under the trade I name Vinylite falls in the latter category.

, form flexible top coats which adhere exceptionally well to my primer coat, such top coat (like my primer coat) being odorless and tasteless.

To a certain extent, the characteristics of the preferred vinyl resins .are retained when the vinyl resin is modified by the addition of a second resin or gum, a cellulose ester, or a high boiling solvent having plasticizing or softening action on withstand extremely rough treatment without b sterilization treatment. In fact, the coating appears to be improved during sterilization. An example of the formation of a dual him the resin. Due to this property, the vinyl resins may be modified to meet specific requirements without materially altering the chemical properties of the resins employed as the top coat.

However, in thefood packaging field, the commercial product sold under the trade name Vinylite without modification is wellsuited for the purpose.

This product is thought to result from the cothe co-polymerizationwith 15% vinyl acetate. y Since my polycyclopentadiene films not only factory results.

- and to heating in the I oxygen-containing gasas a means-of drying my coating or film,-it is to be understood that the." taking on of oxygen by the film need not necessarily take place simultaneously with the heating or baking. On the contrary,

cellent results by heating'or baking the'coatin'gI or the coated object in aninert atmosphere as of nitrogen, carbondioxide, or the like followed by exposure to the atmosphere or other oxygen I top coating of polymerization of about 85% of vinyl "chloridebond well to surfaces but also are highly resistant to attack by foods, and do not impart taste or odor thereto, they may be-used as top coats over primer coats of other materials, if desired. It is, of course, understood that my polycyclopentadiene resin may be used for both a primer coat and a top coat or in any othernumber :of coats.

=With respect to the temperatureand time of baking my polycyclopentadiene films,. I usually 1 its application, or applying the vulcanization agentover the-film after its application, or enclosing the applied film in an atmosphere of vulcaniz'inggaasuch-as HzS, or any combination prefer not to exceed about 40091. andat such temperatures a baking time not longer than about minutes to avoid any possible injury tothe if film. *However, in :one experiment I was able to maintainabaking temperature of 425 .F. for

70 minutes without injury to the film. Thus, although my resin films may be safely subjected to higher temperatures during. baking, in-general, j

-' of the foregoing; or otherwise. The application of heat hastens the drying or hardening action.

' Filmsfof excellent character are obtained when theapplied films are dried or hardened using HzS with' the application of heat.

1 "For exampldasolution 'of my resin may con- I find teir peratures up to 350 F. and baking'.'

times up tominutes very satisfactory. With higher temperatures the-bakingtime may be shortened to yield similar satisbroadly, l

' atmosphere or other oxygen-containing gas, say

correspondingly While I"'have referred lid-baking presenceof air-' or an containingmedium.

I dditional drying or hardening of the film re s suits fromthe absorption of oxygen.

Similarly, in preparing my multiple-film SYS'? Similar'drying procedure may be "tain dis'solved, H23 and after its application to 20:

the metalsurface, thefilm maybe dried in an atmosphere of HiSwith the application of heat.

' A; baking temperature'of 350--F. and a baking time'of l5 'minute s is illustrative.

' Vulcanizedpolycyclopentadiene films may not be oxygen containing', and may or may not be capable of'taking up oxygen, if exposed to the at a greatly 'redu ced rate. I

I I applied to the'vinyl top "coat, if desired; I f'Refe'rence is made to my copending applica- Ihaveobmmed f non Serial'No. 370,138,'fil ed December 14, 1940.

After-dryingor hardening my polycyclopentadiene films are, generally speaking, insoluble.

tems and particularly a system including" my,

I resin film and a Vinylite, film, the drying or hardening of my cyclopentadiene resin film may be secured (a) by baking or heating in anoxygencontaining atmosphere, or (b) baking my'cyclo-i pentadiene resin film in an inert atmosphere but permitting it to stand or fseason in contact with an oxygen-containing atmosphere for ag., alweek) before applying the .r Vinylite, or (c)*baking or heat-' 1 ing my cyclopentadiene resin film in an inert film with the top and then letting the dual period of time (c.

atmosphere, coating the baked coating of Vinylitef I film stand or -season" in contact wth an oxygen-containing atmosphere such as before using the coated article for its intended purpose (in the last-named case, oxygen evidently penetrat es or seeps through the top resin film to mycyclopentadiene resin primer coat), or (d) applying and heating my cyclopentadiene resin film in an inert atmosphere-coating with atop coat film, such as Vinylite," still in of another resin an'inert atmosphere, and heating the multiplefilm system thus formed, still in an inert atmos- "While thefilm thicknesses given are found to ='be extremely suitable for the purpose, and particularlyfor food containers, other film thick-* nesses may-obviously be employed without departing from'thespirit of the invention.

While in the above specific examples toluene isused,-it is tobe understood that-other suitable solvents may be employed with corresponding results of which benzene, xylene, ethyl benzene,

naphtha, chloroform and carbon tetrachloride are examples.

While the foregoing particular description has been concerned primarily with the application of the protective film or films to metal sheets of a gauge used in the manufacture of tin cans,

"cation Serial No. 491,947,

phere, or"(e) any combination of any of the fore-- going.

- Since the resin coating resulting from (d) wherein the entire series of operations take place in an inert atmosphere is entirely satisfactory for I vention.-

any well to my primer coat, such top coat like commercial use, my cyclopentadiene resin films either by heat, v

may be. satisfactorily hardened or by an oxygen-containing environment or by a combination of both. I

it will be obviousfthat my invention is not limited thereto but may be applied to any metal sheet material, and in fact, to metallic objects in general whether prefabricated or not, where a tough strongly adhering film or film system is desired.

Thus, theresin film may be applied to metal.

foil. Reference is made to my copendingapplifiled June 23, 1943. As an illustration, tin foil and aluminum foil, each of whichis used to package dairy products like butter'and'cheese, may beso coated. If desired, these materials'in molten form may be poured into molds linedwith foil coated in accordance with my invention.

So too,lead foil, such as is used to package tea leaves; may becoated inaccordanee with my in- I Metal foil'may be coatedby any desired procedure. For example, the foil may be passed through a solution of the coating material and the-excess removed by means of doctor blades or rolls. Or a'conventional r011 type coating pro- 1 cedure may be employed and the solvent removed and/or recovered in a drying tower.

metal foil may be strengthened by If desired,

rial has completely dried. I V by coating the opposite side of the metal foil and dryingthe filmfor contact with foodstuffs. On the other hand, metal foilcoated with my dual 7 1 filmsystem with Vin ylite as the top coat may be hot pressed-against paper or foil to efiect it withpaper, or, by, laminating two or r mclilre foiI -layrs.#-F or example'a sheet of metal t V bejcoated-on one side and the coated sidepressedintocontactiwith a sheetof paper or second sheet. of foil beforethe coating mate- This may be followed union of the materials. While the invention has been more particularly described in connection with the coating of sheet metal including foilin the flat, my resin film or film system may be applied during or after any forming operations forconverting; the initial material into the finished object- It is generally useful for coating metallic objects in general,

whether fabricated from sheet metal or not, or whether pre-fabrica'ted in whole or in part prior to application of the, film or film system.

While it is preferred to employ it without additives, the addition of other substances may be made with consequent modified results, provided the outstanding characteristicsof thematerial are not substantially destroyed. The presence V of apolymerof methyl cyclopentadiene per se or a, co-polymer' or cyclopentadiene and methyl cyclopentadiene, or. both, in amounts up to of the order of from 10 to 20% and possibly more,

- appears to have no deleterious effect. This does not apply to resinous materials, in, general and extreme care should-be exercised in making any J additions.

By the termffhomo-poiymeri is meant the result of the additive combinationof amonomer and/or polymers of the same. monomer, as distinguished from aj..co-polymer.. which results from the additive combination-of different monomers and/or polymers of diflerentmonomers. The presence of up to 20% ormore of methyl cyclopentadiene in the starting'material of Examples 1 and 2 appears. to have no outstanding deleterious effect and the resulting polymerized product is defined incertain of the. claims as resinous co-polymer of cyclopentadiene and methyl cyclopentadiene in which copolymer the proportion of methyl cyclopentadiene. does, not exceed 20%. The absence of all other materials polymerizable-underthe conditions employed is pre- U ferred. In fact. forth preparation of protec- ..tive films giving the best results from every standpoint, itispreferred that there be present in.:the; starting materials no substantial quancities of; any other, materials (besides the cyclopentadiene and methyl cyclopentadiene) which will form a resin under the polymerization conditions prevailing.

My polycyclopentadiene films are naturally colored in beautiful old gold. If desired, suitable coloring materials may be added such as dyes, pigments, and lakes. The same applies with re- 7 'spect to the Vinylite top coat. However, in the food packaging field, care should be exercised withrespect to any additives so as not to lower or destroy the excellent qualities of the original material for this particularuse.

Since in' the food packaging field the important. consideration is that the resin in contact with the" food be chemically inert, insoluble in the foodstuff, incapable of imparting odor and taste thereto, and strongly adherent to the enclosing wall, outside portions of the container or foil may be left uncoated, or may be coated changes, omissions, additions. substitutions,

and/or'fmodifications may be made within the scope of the claims without departing from the spirit of the invention.

I claim:

1. A formed film-coated article shaped by deformation of a metallic body coated with dried resinous polymer of cyclopentadiene selected from the group consisting of resinous polycyclopentadiene and resinous copolymer of cyclopentadiene and methyl cyclopentadiene in which copolymer the proportion of methyl cyclopentadiene does not exceed 20%, said formed film adhering tenaciously to the formed metal.

2. A formed film-coatedarticle shaped by drawing a metallic sheet coated with dried resinous polymer of cyclopentadiene selected from the group consisting of resinous polycyclopentadiene and resinous copolymer of cyclopentadiene and methyl cyclopentadiene in which copolymer the proportion of methyl cyclopentadiene does not exceed 20%, said formed film adhering tenaciously to the drawn metal.

3. A formed film-coated container cap shaped by drawing film-coated metallic sheeting coated with driedv resinous polymer, ,of cyclopentadiene selected from. the group consisting of resinous polycyclopentadiene and resinous copolymer of cyclopentadiene and methyl cyclopentadiene in which copolymer the proportion of methyl cyclopentadiene does not exceed 20%, said formed film which copolymer the proportion of methyl cyclopentadiene does not exceed 20%, said formed film adhering tenaciously to the drawn metal ineluding thethreaded portion thereof.

5. A formed film-coate'd'food container shaped by deformation of metallic sheeting coated with dried resinous polymerof cyclopentadiene selected from the group consisting of resinous polycyclopentadiene and resinous copolymer of cyclo- .pentadiene and methyl cyclopentadiene in which copolymer the proportion of methyl cyclopentadiene does not exceed 20%, said formed'film ad-' hering tenaciously to the formed' metal. r

6. A food package comprising formed filmcoated metallic sheeting shaped by deformation of metallic sheeting coated with a primer coat of dried resinous polymer of cyclopentadiene selected from the group consisting of resinous polycyclopentadiene and resinous copolymer of cyclopentadiene and methyl cyclopentadiene in which copolymer the proportion of methyl cyclopentadiene does not exceed 20%, and a top coat of dried resinous copolymer of vinyl chloride and vinyl acetate, said package for food having at least the surface thereof which would otherwise comein contact with the food to be packaged coated with the formed film, said formed film adhering tenaciously to the formedlmetal.

7. A food package comprising formed filmcoated metallic sheeting shaped by deformation of metallic sheeting coated with dried resinous polymer of cyclopentadiene selected "from the, group consisting of resinous polycyclopentadiene I portion of dried resinous .coat'ed with-a i'ormed protective layer 1 -thetic resin'which comprises coating metallic material fromwhichthe article is to be formed with resinous polymer of cyclopentadiene selected pentadiene and methyl cyclopentadiene in v diene does not exceed 20%,

and resinous copolymer of cyclopentadiene and methyl cyclopentadiene in which copolymer the proportion of methyl cyclopentadiene does not exceed "20%,-said food package having at least the surface thereof which be packaged coated with the formed film, said formed film adhering strongly to the formed metal.

' with-' resinous polymer "of cyclopentadiene selected 'from' the group consisting of resinous'polycyclopentadiene and resinous copolymer of cy-- clopentadi'enefand methyl cyclopentadiene in which copolymer the proportion of methyl cy- "clopentadie'ne does not exceed 20%, drying said i would otherwise come in contact with the food to 8. A formed film-coated article shaped by body coated with an oxidized drawing a metallic formed film adhering tenaresinous film, said coating, applying over said'first-mentioned coating' a second'coating' of resinous copolymer of vinyl chloride and vinylacetate, drying said secend-mentioned coating','-and subjecting the coated sheeting to shapingoperations to produce said 4 formed article.

ciously to the formed metal and being comprised preponderantly of oxidized resinous polymer of material containing at least one of a group consisting of (a) cyclopentadiene and (b) cyclo- 13. A process -for producing a formed coated article with a formed protective layer of synthetic resin whichcomprises coating metallic material from which the article is to be formed with a jsinallproportion of resinous polymethyl pentadiene in admixture with up to'20% of methyl cyclopentadiene as substantially the only resin forming content of said materiaL' 9'. A formed film-coated article Shaped by drawing a metallic sheet coated with a smallpropolym'ethyl cyclopentadiene in admixture with not exceeding 20%. i 10. A process for producing a formed. article oi syncyclope'ntadiene in admixture with resinous polycyclopentadiene said proportion of polymethyl cyclopentadiene-not exceeding 20%, drying'saicl c0ati'ng,'and subjecting the coated material to i shaping operations to produce a formed article.

dried-resinous polycyclopentadiene, said formed film adhering tenaciously 'tothe drawn metal, and the proportion of polymethyl cyclopentadiene in said admixture H from the group consisting ofresinous polycyclocyclowhich copolymer the proportion of methyl cyclopentadryingsaid coating,

pentadiene'and resinous copolymer of and subjecting the coated material to shaping operations to produce a; formed article.

1 11. A method for producing a coated can cover having sharplybent coated-"portlons from-metallic sheeting which comprises coating said sheeting from which the can cover is to be formed ,withresinous polymer of cyclopentadiene selected from the group consisting, of resinous polycyclopentadiene and resinous copolymer of cyclepentadiene andmethyl cyclopentadiene in which copolymer the proportion of methyl cyclopentadiene does not exceed 20%, drying said coating, .cutting a blank of the desired shape from said sheeting, and die-drawing said coated blank to the desired can cover shape having said sharply bent portions.

12. A process for article coated with producing a formed metallic I a formed protective layer of i synthetic resin which comprises coating metallic t sheeting fromwhich t e article is to be formed 'res'inous polycyclopentadlene =14. A formed film-coated article shaped by deformation 'of a metallic body coated with a primer coat of dried resinous polymer of cyclopentadieneselected from the group consisting of and resinous copolymer oi cyclopentadiene and methyl cyclopentadiene inwhich copolymer the proportion of methyl cyclopentadiene does not exceed 20% and a topcoatof dried-resinous polymerized vinyl ester, saidformedfilm'adhering tenaciously to the *formedmetal; II

:-15.'A formed film-coated article shaped by drawing a metallic sheet coated with dried resinous polycyclopenta'diene said formed film adhering tenaciously to the drawn metal.

16. A formed-film-coated can shaped :by drawing a metallic sheet coated with dried resinous polycyclopentadiena's'aid formed film adhering tenaciously to the drawn metal.

- 17. A- fcrmed-"film-coated article shaped by drawing tin plate coated with dried resinous polycyclopentadiene,said 'formed film adhering tenaciouslyto-the drawnmetal.

18;A formed film-coated article shaped by drawing an iron shet'coated with dried resinous polycyclopentadiene; said formed film adhering tenaciously to the drawn metal.

19. A formed film-coated can shaped :by drawing a metallic body coated with an oxidized resinous film, sai'd'formed film to the formed metal and adhering tenaciously being comprised preponderantlyof oxidized resinous polymer of material'contalning cyclopentadiene as substantially the only resin forming content thereof.

NEwcoMB K. CHANEY.