US1360318A - White-enameled steel vessel - Google Patents

Description

UNITED STATES PATENT OFFICE,

SIMON RIESER, F MIDDLETOWN, CONNECTICUT, ASSIGNOR TO THE NEW ENGLAND ENAMELING (30., A CORPORATION OF CONNECTICUT.

WHITE-ENAMELED STEEL VESSEL.

No Drawing. Original application filed November 21, 1916, Serial No. 132,562. Di

cation filed July 16, 1919. Serial No. 311,377.

To all whom it may concern: Be it known that I, SIMON RIESER, a citizen of the United States, and a resident of Middletown, in the county of Middlesex and State of Connecticut, have invented a new and useful Improvement in lVhite-Enameled Steel Vessels, of which the following is a specification.

My invention relates to white enameled steel vessels. Its object is to produce such vessels with a single white enamel coat applied directly on the steel.

It consists in the novel products hereinafter set forth.

Although many attempts have been made to produce a single white enamel coat on steel, it has heretofore been found impossible to do so on a practical commercial scale or to produce a single white enamel coat on steel that would be durable or that would be and remain free from mottling or staining. Whenever a single enamel coat has been applied directly to the steel, it has been found impossible, either to produce a color sufliciently light, or to prevent the lightening properties of the materials used being lost or destroyed in the process of manufacture, or to prevent such white enamel coat from mottling or staining, or to make such white enamel coat durable or possessed of sufficient sticking properties to remain intact upon the steel in practical use. Either the batch or mix has not been such as to permit the finished single coat to become white or to remain White, or the light color obtained during the process of manufacture has been destroyed, or the enamel coat has not possessed sufficient sticking properties, or appears as a mottled or stained coat, or becomes so after bein produced, or will finish as a rough, pitte face.

I have succeeded in overcoming all these difficulties and in producing a white enameled steel vessel having a single white enamel coat applied directly on the steel, which coat not only has the necessary sticking qualities, but appears and remains white without mottling and staining, and is durable in practical use. It is as durable and useful, and presents as white a surface, as white enameled steel surfaces which have Specification of Letters Patent.

Patented Nov. 30, 1920.

vided-and this app11- heretofore been produced by using more than one coat, and its manufacture is less complicated and much cheaper.

I will now roceed to explain the preferred process y which I produce my improved product, although it will be understood, of course, that many variations may be made in the materials used, in their proportions, and in the specific steps taken, wlthout departing from my invention.

Referring now specifically to the process which I prefer to follow in making my improved product, I first make a batch or mix that will, when smelted, ground and mixed with the White-color-giving constituents, permit such constituents to impart a white color to the finished enamel coat. This I obtain by using the materials hereinafter set forth for the mix, or their equivalents.

I have found in practice that the followlng materials, with the proportions stated for each, give satisfactory results when used as a batch or mix, namely Borax 270 lbs. Feldspar 336 lbs. Quartz 120 lbs. Soda ash 90 lbs. Fluorspar 26' lbs. Bone ash 4.0 lbs. Refined sodium nitrate 30 lbs.

White antimony, S13 0, oxid of antimony, Sb 4 52 lbs. Ammonium carbonate 8 lbs. Black oxid of cobalt, C0 0 41oz.

Some of the above ingredients are used in making the batch or mix commonly employed for the ground or grip coat upon which a white coat or coats are superimppsed to form White enameled steel vessels.

y improved mix differs in ingredients and proportions from the ingredients and proportions of such a ground or grip coat in omitting certain materials that tend to darken, such as oxid of manganese and needle antimony, in using white antimony $10 0, or oxid of antimony, Sb O,,, in using a smaller proportion or amount of fluorspar, and, generally, in using a larger amount or proportion of materials that tend to lighten as distinguished from those that tend to darken, and also in omitting cry lite, commonly employed. in a superimposed 'whitecoat or in a white coat superimposed imparts suitable sticking properties to the finished enamel, and will not prevent the white-color-giving constituents, hereinafter referred to, from imparting a permanent white color to thesingle enameling coat.

The batch or mix thus made is smelted in the usual way to form a frit. The frit is then ground in the mill with the usual amounts of water and clay, suitable for the purpose, added thereto, and is ground to the proper consistenc the same as in the ordinary treatment or preparing a dip. The quantities of water and clay that I prefer to use are :-Of water, 33% per cent. of the weight of the frit; of clay, 6 per cent.

' of the weight of the frit. The ground mix ture thus obtained'would, in the ordinary process of enameling upon steel, be called and treated as the mill contents. In my preferred process, however, I preferably re-' move a portion of the soluble enameling constituents, such as soluble borates, silicates and the like, by allowing the mixture to stand until the heavier constituents have settled, and then I dip off the overlying layer of water with its soluble contents. The remainder, in my process, constitutes the mill contents. Any other suitable way may be used for obtaining in the mill contents the less amount of soluble constituents above described, such, for instance, as by put ting into the batch originally less amounts of such constituents.

I then mix a suitable proportion of the .mill contents with white-color-giving constituents, in such proportions as to impart to the mixture a white color when properly set up and applied as a single enameling coat to steel, without grinding the constituents of the mixture any more than is enough to mix them sufliciently, so as to preserve the coarseness of the white-colorgiving constituents, to conserve their whitecolor-giving capacity or to revent .the grinding out of their color. preferably accomplish this by using in the mill a relatively small number of pebbles compared to those ordinarly used in enameling processes,

and I grind the mixture in the mill a relatively short time. Thus, a sufiicient mixture of the various constituents is obtained,

while preserving the coarseness of the whitecolor-giving constituents.

Any suitable white-color-giving COHStIt".

uents may be employed, but 7 prefer to use as such a mixture'composed of sodium antimoniate, tin oxid, and antimony sulfate,

i or their equivalents, in suitable proportions.

I find, in practical use, that the following proportions ofthese various substances give satisfactory results, namely:To mix with 500 pounds ofthe mill contents, 117% ounces .of sodium antimoniate; 27% ounces of tin i the mill contents.

I have found that, if the mixture of the mill contents and the white-color-giving constituents is ground too thoroughly or too long, it tends to destroy their white-colorgiving properties when applied as a sin le white enameling coat to steel. Thus, if t e usual amount of pebbles is used in the mill,

or if the grinding is kept up too long, the white color will disappear in the product.

I have found in practice that from about three-quarters of an hour to about an hour in grinding, with one-half of the pebbles used in the mill, gives satisfactory results.

After this grinding, the mixture is drawn from the mill and allowed to cool. It will cool in from three to six hours, although I prefer to allow from six hours to a day. The mixture thus produced I will, for sake of convenience, refer to hereafter as thev enameling mixture.

This enameling mixture is then ready to be set up.

I next prepare a setting up mixture by dissolving ammonium carbonate, or its equivalent, in water, in suitable proportions, and mix this setting up solution, preferably while hot, with the enameling mixture prepared as above described, mixing in suitable proportions with the enameling mixture, and stirring the two until the proper consistency is obtained. The object of using ammonium carbonate is to set up the enameling mixture without producing mottling in the finished enamel, and any material that will do this is an equivalent for the carbonate of ammonia.

The ammonium carbonate may be dissolved in water in any suitable way, but I preferably do this by boiling it until the ammonium carbonate is dissolved. I have found that equal weights of ammonium carbonate and water will give satisfactory results. The setting up mixture and the enamelin mixture may be combined in any suitable proportions. I have found that 8 ounds of the setting up mixture when mixe with the amount of enameling mixture produced as above described will give satisfactory results.

The mixture should be stirred actively until the desired consistency is obtained. In practice, I prefer to continue this stirring until a heavier or thicker consistency is obtained than is usually employed in the dip, for I have found that better results are obtained by diluting such a heavier consistency with water as required When the dip ping of the steel vessel into the mixture is performed.

I have found that the use of the setting up mixture above described tends to prevent mottling or staining of the single White enamel coat when applied directly to steel. It does this, as I understand it, because it i does not produce a strong salt, such as nitlates, chlorids, sulfates, etc., all of which tend to produce mottling.

The various steps of my process, the constituents used, and their proportions may, of course, be Widely varied.

By my improvement, a durable, practical white enameled surface can be produced on steel by the application of a single coat directly to the steel. The surface presents as good an appearance as that of a White enam' eled surface that has received tWo or more coats, and is as free from mottling or staining.

The ordinary operations of cleaning, pickling, Washing and drying of the vessels or surfaces to be enameled must be carried out With particular care, to insure complete freedom from dirt of all kinds and also from traces of acid.

In the above-described preferred method of carrying out my process, I have referred to the mixing of the mill contents With the white-color-g1ving constituents as being done in a mill and by grinding. It is not essential that this mixing be done in this manner. Any suitable Way or means for mixing the mill contents and the Whitecolor-giving constituents may be employed, and it is not essential for this purpose to use a mill, or even to grind the two together, although that is my preferred Way.

The present application is a divisional application of my application Serial No. 132,562, filed November 21, 1916, for process for producing a single White enamel coat on steel and the product resulting therefrom.

What I claim as new and desire to secure by Letters Patent is As an article of manufacture, an unmottled White enameled steel vessel or surface provided With a single White enamel coat placed directly upon the steel.

In testimony whereof I have signed my name to this specification.

SIMON RIESER.