US2441227A

US2441227A - Method of applying temporary protective coatings

Info

Publication number: US2441227A
Application number: US533015A
Authority: US
Inventors: Bernard M Pineles
Original assignee: United Shoe Machinery Corp
Current assignee: United Shoe Machinery Corp
Priority date: 1944-04-27
Filing date: 1944-04-27
Publication date: 1948-05-11
Anticipated expiration: 1965-05-11
Also published as: BE576351A; FR960869A; GB649046A

Description

May 11, 1948. B. M. PINELES METHOD OF APPLYING TEMPORARY PROTECTIVE COATINGS 2 Sheets-Sheet 1 Filed April 27, 1944 y 1948 B. AM. PINELES' 7 23443 22"? METHOD OF APPLYING TEMPORARY PROTECTIVE COATINGS Filed April 27, 1944 2 Sheets-Sheet 2 lnmmiar Bei'na I'd/1 fine/ea Patented May '11, 1948 PROTECTIVE COATINGS Bernard M. Bineles,

United Shoe ton, N. J., a corporation Corporation, oi New Jersey Hamilton, Mass assignor to Flc lnlr Application April 27, 1944, Serial No. 538,015

3 Claims.

1 'This invention relates to the method of applying by means of a spray a temporary protective coating of a film-forming colloid, which may be readily peeled or article having gaps or openings in its surface.

Many articles, to which films or coatings are to be applied, have gaps or openings in their surfaces. For example, the barrel of a machine gun is commonly surrounded by a hollow supporting jacketv the wall of which has holes in it, and there are larger openings in the walls which enclose the firing mechanism. Examples of larger articles having openings which lead into their interiors are automobiles and airplanes. When such articles are to be coated it is desirable first to cover or bridge over all openings, except perhaps in certain cases very small ones, before applying to the article its temporary protective film or coating. It is possible, of course. to cover such openings by means of some extraneous material such as cloth, paper or adhesive tape, and then to spray on the solution oi film-forming colloid.

According to the present invention the gaps or paratively dry; and then over these bridging coatings and over uncoated portions of the article there is applied, by means of a spray, the particles of which are smaller, probably globular or nearly so, and wetter than those of the bridging spray, a coating which amalgamates with and adheres firmly to the'bridging coatings to form a tough, flexible, temporary protective coating which adheres lightly to the article and may be readily peeled or stripped off when desired. In practice a spray gun may be coating as may be desired.

Fig. 3 is a perspective of the same machine gun as is shown in Fig. 1 after all the openings have been covered by a bridging coating of comparatively dry filaments, and then a second superstripped oil when desired, to an NT OFFICE G TEMPORARY l posed coating has been amalgamated with the lightly adherent bridgin v tegral coating covering the entire which may stripped of! when desired.

upside 9, ll (both being one post receiving an en .The machine gun I whi coat'ingto' form an inch is. tobe coatedis down upon two crotched posts shown in Fig. 3), the crotch of a the d of thebarrel, and the receiving aportionlof a rear of thegun. The

expose all parts 'of its surface to the action of. a

spray which issues from a the operator in one hand w rotates the machin The spray gun sion of spray from the m trolled by a trigger two valves 2|, 23 w by turning their controls'the fiow air throughtwo 25 which is-- fast to shown) being pro upon the spray closed and the the general form to spray material passin is so adjusted that t globular or nearly so a the, regular wet s trols the flowof original position; 68 supply more air a of 89m as to provide more into the fan-shape shown. is closed, the spray has the the proportion of air to s than when the valve 2| to the spray gun, from an air shown) through a "tube .21, the air compressor and the s shown) manipulation 01 Win of the air. A seco of supply (not shown) under tion'of spray material to..a

Spray.

spray gun I'I held by hile with the other he e gun as may be desired. a commercialtone, the emis-v ain nozzle being con- IS;' The gun is provided with hich may be opened and closed knurledheads. The valve 23 air and to 'fiatten the spray y material. The valve 2! does not control the flow of air throu gh the main nozzle. When opened, it permits fiow of extra small

auxiliary nozzles

24,25 soout the spray :F When the valve-2l. shape or a cone, and pray material is less pray guna valve (not ch varies the pressure nd tube 29 leads from a source I pressure of the solusmall receptacle 3! gun, a valve (notf vided for varying the pressure material. When the valve 2| is as has been stated, has

of a cone, the proportion of air through the main nozzle he particles of spray are nd contain acomparatively large amount of solvent, this spray being termed as, distinguished from the rticles of which are in the long, comparatively dry' spray may be produced by n of spray'material to air, ngto a larger extent the valve i wever, the valve 23, which conspray material, remains Lin-its.

and the valve 2 t is nd to flatten'out the opened to spray into openins the fan-shaped spray it shown, a comparatively thin fiat fan-shaped spray bridging certain openings in a pears below.

manner which apto the rim of the opening, and there res at random. an the large openings, means of this bridging coating, the proportion of spray material to air is again adjusted to produce thespray referred to above as the regular wet spray, the particles of which are globular, or nearlyso and contain a greater proportion of solvent to solid when they strike the e Si F; used to apply a coating and over uncoated portions of the machine gun. The superposed coating adheres firmly to and amalgamates with the bridgin coatings to form an'integral coating which, like the bridging coatings, adheres lightlyto the articles. somewhat drier than the regular spray and is referred to herein asa spray of long, comparatively dry filaments. lightly adherent coating; the following comparaspray forms a coating which amalwith the bridging coating and adheres lightly to the article; and there results a single coating which mayreadiiy off.

with regard to the,term-"lightlyjadherent," the filaments adhere in a certain degree to the article and in a greater degree to each other so vthat a brid coating of filaments more or less entangled and superposed at angles upon others beneaththem is formed which remains in place while the somewhat wetter, more or less globular particles or the following spray are deposited $119 tins which amalgamates cl es peins theltlis no bridglnil partly laminated coating readily peeled or stripped of! when desired. The above is true even though the article to be coated has upon it, as frequently happens when the article is a machine-mm. a thin coating of light lubricating oil. At least it is certain that the bridgin coating above circumstances. As to the following coating inthe case of an article such as a ma hine gun which has a light coating of oil, it may be that the lightly. adherent quality of the enveloping coating is due in large measure to the shrinkin which takes place when the solvent evaporates.

Thereis, of'course, a limit to the size of an which may be bridged by the spray of filaments. Just what the limit is, "but an opening, the smallest dimension of which (is about 8", may readily be bridg d. y v

coating, the amalgamated being capable of being being preferable in ults a The spray of filaments is be peeled or stripped adheres lightly even under the- I in its top, said' opening being that is,

This spray results in a .Presently other filaments adhere large articles or objects, such, for example, as airplane wheel housings have larger openings, and consequently in general no difllculty is encountered. Fig. 2, which is illustrative of how the bridging is done, shows a generally cylindri: cal ceramic vessel 3| with a circular openin considered for purposes ofdiscussion to have a diameter of 83'. The spray, as has is a thin, fanshaped one. The filaments do not need, in this case, to be 8" long. They may he, say, l"-3" long. As the spray strikes the locality of the rim of the receptacle nearest to the spray gun, some or these traveling filaments adhere to the rim and extendto some extent over the opening. to the free ends of the first filaments; and this process proceeds with following filaments until the filaments added one to another extend across the opening. The fan-shaped spray is held at a comparatively small angle to the plane of the opening. which in the figure is horizontal, and is swim! back and forth in an arc while maintaining the angle substantially constant. There thus results a bridging coating made up of a network of filaments arranged at random, more or less tangled, and extending at different angles over others beneath them.

Assuming that the proportion of compressed air .to spray material passing through the spray gun is such that the spray is what has been termed the regular spray and consists of globular or similarly shaped particles which, with the nozzle of the spray gun held at a convenient distance, says or 6 inches, from the article, will produce what has been termed the wet coating,

one which will dry out to a tough, he:- adherent film, the procedure of approtective coating to an article, such, for example, as 'a machine gun, which has openings in its surface, is as follows. The proportion of compressed air to spray material is increased, the valve 2! being preferably opened somewhat. There is thus produced a thin fanshaped spray the particles of which are comparatively long,. comparatively dry filaments. The spray gun is preferably held farther from the article, say 15', the bridging coatings.

lble, lightly p yi a tempora In the above specific have been given, the pressure upon the spray material may be 15 lbs. per square inch and that on the air 30 lbs. per square inch. After the openings have all been bridged by the use of this spray. the proportion of compressed air to spray material is decreased once more, for example, by closing the valve 21 to produce the regular spray of globular or similarly shaped particles which contain more solvent when they strike the articles than did the filaments of the bridging spray. The spraying is then continued with the spray gun held at, say. 4 or 5 inches from the article, to apply over the bridg ng coatings and over uncoated portions of the article what has been termed the regular wet coating, which amalgamates with the bridging coatings to produce with said bridging coatings a single coating which may be readily peeled or stripped oil when desired. There has been described above a brid during the application of compatible so that one coating will amalgamate with the other.

It is possible to use the regular spray to produce both the bridging coating and the superposed regular coating by first holding the spray regular coating; but this procedure has the disadvantage that, when the spray gun is held at a suflicient distance from the article to produce suitable filaments, only a comparatively small number 01' spray particles strike the article at any iven moment so that a considerable part oi the spray material. is wasted. and bridging the openings requires a much longer application or the spray. The other possibility, namely to make use only or the bridging spray sun close to the article to that holes are liable to be made in the bridging coating. Below are several examples of spray material.

Example I Parts by weight Vinylite VYNS Acetone 85 Vinylite VYNS, a product oi' Carbide and Carbon Chemicals Example It Parts by weigh: 1

Vinylite VYN 3GH 5 85 Acetone 38H, a product of Carbide and Carbon Chemicals Corporation, of New York, is triethylene glycol dl-2-ethyl butyrate and is a plasticizer specially designed for use with Vinylite resins.

Example III 1 Parts by weight Vinylite XYBG 10 Methanol 90 Example IV Parts by weight Vinylite XYSG 8 3GH 4 Methanol 88 Vinylite XYSG. a product oi Carbide and Carbon Chemicals Corporation, of New York, is an acetal which results from reacting polyvinyl alcohol with butyraldehyde.

Example V Parts by weight Polymerized methyl methacrylate 10 Ethylene dichloride 90 Example VI Parts by weight Polymerized methyl methacrylate --10 Dibutyl phthalate 5 Ethylene dichloride 5 In the above example the spray material con- 76 filaments or film-forming sists of a resin and a solvent withor without a plasticizer. It should be understood, however. that various other ingredients may be used it desired. For example. the spray material may have the following composition which. since it contains a corrosion inhibitor, forms part of the subjectmatter of application serial No. 736,514, filed March 22, 1947, which is a Oil 1255, a non-corrosive, non-drying oil, is 'a product oi. the Standard Oil Company of New Jersey.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. The method 01' applying a temporary protective coating to an article having an opening in oil when desired.

2. The method of applying a temporary protective coating to an article having an opening in a wall thereof, said method comprising providing a spray material in the form of a vinyl resin or a gas under form of comparatively long, comparatively dry colloidal material to travel over the opening in such manner as to build upi-e. bridging coating, and then cousin: 0, generally cone-shaped spray the particles 01 which are smaller and wetter than the filaments to travel over the bridging coating and over ancoated portions 01 the article to form with the bridging coating a tough, flexible temporary protective coating which adheres iizhtiy and ma be readily stripped of! when desired.

' BERNARD M. PINELEB.

nnrnnnncns crmn The loilowina references are or record in the file 0! this patent:

" um'mn sums PATENTS Number Number I Name Date Moyses Apr. 10, 1934 Ericson Mar. 28, 1943 FOREIGN PATENTS Country Date Great Britain Mar. 3,1948