US1582343A - Method of manufacturing mold powder - Google Patents

Description

Patented Apr. 2.7, 1926.

UNITED STATES PATENT OFFICE.

xomum nttnmmjor LUNEBUmaeEmrANY, assrenon 'ro 'rnr. FIRM B. noes a G0. or BERLIN, GERMANY.

METHOD OI MANUFACTURING MOLD POWDER.

Drawing To all whom it may concern:

Be it known that I, KONRAD Mr'iLLnn, a citizen of the German Republic, and residing at Luneburg, Germany, have invented certain new and useful Improvements in a Method of ,Manufacturing Mold Powder, of which the following is a specification.

In former times witch-meal (lycopodium) has been employed as mold-powder, but as its price is high various surrogates have been introduced by and by,as, for in stance, carbonate of lime, kicselgnhr,tripolipowdeiybrown-coal, and a lot of other substances. As the chief property of the moldpowder must be its complete repulsion to water, the substance used is soaked with a comparatively considerable amount of a suitable wax or oil, a suitable fatty acid, or the like, whereby it is rendered water-repulsive. The quantity of the respective added substance (wax, etc.) amounts, as a rule, from 3 to 10%, but in some cases it is considerably greater.

Now, I have discovered that a large part of the wax or other added water-repulsive substance can be saved if pieces of unglazed muflles or the like as used in connection with the burning of chinaware or clay-ware are ground, and this powder is used as a substitute for the carbonate of lime, kieselguhr, etc., etc. Only about of the wax, etc., is neededto render the composition completely water-repulsive and to lmpart it also the certain other properties necessary for a useful mold-powder. EwampZe.-2O0 kg. of finel ground unglazed mufile-pieces or the li e are mixed with 1 kg. of "wax or a suitable equivalent, and with a small amount of a dyeing substance of such a color that the composition a'ssumesa color like, or similar to, that produced by witch-meal, the mixingbeing effected preferably by means of a stirring-device and at a temperature of from 7 0 to C. The mixing by stirring is continued for about 1 hour, when a homogeneous composition will be obtainedthat can be employed Application fil ed November 21, 1924. Serial Np. 751,413.

as mold-powder either at once or after having been sifted.

I claim:

1. The method of producing a mold-powder, consisting in grinding unglazed fire clay muffle-pieces and mixing the powder obtained with wax at a temperature.

which is only a little higher than the fusing ing temperature of the wax, substantially as set forth. I 1

4. The method of producing a parting powder consisting ingrindin pieces of unglazed burnt fire clay and mlxing the powder obtained wtih wax at a temperature which is a little higher than the fusion temperature .of the wax.

5. The method of producing a partingpowder consisting in grinding pieces of unglazed burnt fire clay and mixing the powder obtained with about one-half per cent of wax at a tem erature which is a little higher than the usion temperature of the wax.

6. As a new article of manufacture a parting powder consisting of a mixture of finely groundburntunglazed fire clay with wax which has been incorporated at a temperature slightly above the fusion temperature of the wax.

7 As a new article of manufacture a 1parting powder consisting of a mixture of nely ground unglazed mufiie pieces with wax which has been incorporated at a temperature slightly above the fusion temperature der so obtained with a water repellent maof the wax. I terial. n

8. The method of producing a parting 10. As a new article of" manufacture a powder consisting in grinding pieces of unparting powder consisting of finely ground 5 glazed burnt fire clay and intlmately mixing burnt unglazed fire clay with which has been 15 the powder so obtained with a water repelthoroughly incorporated a water repellent lent material. material.

9. The method of producing a parting In testimony whereof I have afiixed my powder consisting in grinding unglazed signature. muflle pieces and mixing intirnately the pow- KONRAD MULLER.