US1918418A

US1918418A - Method of producing abrasive paper and the like

Info

Publication number: US1918418A
Application number: US561883A
Authority: US
Inventors: Munch Carl
Original assignee: Individual
Current assignee: Individual
Priority date: 1930-09-09
Filing date: 1931-09-09
Publication date: 1933-07-18
Anticipated expiration: 1950-07-18

Description

m 18, 1933; c. MUNCH 1,918,418

' METHOD OF PRODUCING ABRASIVE PAPER AND THE LIKE Filed Sept. 9, 1931 Jn van for:

1 AZLfornez s Patented July 18, 1933 cam. ufincn, or DUREN, GERMANY METHOD OF PRODUCING ABBASIVE ZPAPER AND THE LIKE Application filed September 9, 1931, Serial No. 561,883, and in Germany September 9, 1930.

lulose ester solution is applied alone on to the support, whereupon the abrasive is strewn on to-the applied layer whilst the same is still sticky. Consequently, these known methods are inconvenient and waste 15 time, and on the abrasivepaper produced thereby the abrasive grains arenot uniformly distributed over the grinding surface and are not sufficiently embedded in the binding medium, so that the grinding surface is also 20 not smooth. The grinding coating of the abrasive paper thus produced is as a rule subsequently provided with a further layer of cellulose ester, in order to smoothen the grinding surface. By this measure however the known processes of the kind in question are rendered still more complicated, without overcoming the objection of the irregular distribution of the grains of abrasive on the support. These inconveniences are overcome according to the invention. 7

The invention consists substantially in that first the cellulose ester, dissolved in a solvent, possessing a low boiling point, is mixed with the abrasive, after which the mixture thus obtained is applied in thoroughly mixed condition continually on to the circumference of a rotating cylinder and then continually brushed off from the periphery of the cylinder by means of a paper or fabric web moved in the same direction and bearing against the circumference of the cylinder so that the mixture is transferred to the paper or fabric web. The new method is much more simple than the known methods of its kind and the abrasive paper produced thereby shows a very uniform distribution of the abrasive particles on the support with proper embedding in the binding medium and consequently a ver smooth surface produced without any furt er measures.

of the accompanying drawmg is preferably 60 employed, which consists substantially of three cylinders, a, b, 0, the two cylinders 12, 0 of which are arranged, rotatable in clockwise direction, side by side so that a gap F is left between them corresponding in width approximately to the thickness of the coating to be applied to the support, whereas the third cylinder a is mounted rotatable in the same direction under the cylinder b at a certain distance so that a passage is left the width of which corresponds to the thickness of the support. The space above the gap F between the cylinder b and the cylinder 0 provided at the top with a scraper. d, is filled with a mixture of cellulose ester solution and granular abrasive, and at the same time the paper or fabric web 6 designed to serve as support is conducted from below over the cylinder a and between this cylinder and the cylinder 6, and consequently conveyed by the so cylinders a, b in the direction indicated 'in the drawing by the arrow. Owing to the rotating movement of the cylinders b and a a continuous effective mixing of the mixture between these cylinders takes place automatically, a portion of the mixture being continually. carried along by the periphery of the cylinder 1) in the form of a thin layer 9, the thickness of which corresponds approximately to the width of the gap F between the cylinders b and 0. As soon as the layer 9 of mixture carried along by the periphery of the cylinder 1) arrives on the moved suport e, it is scraped off from the cylinder 6 y this support and continually applied in a smooth layer onto the support 6, where it rapidly dries.

I claim In a method of producing abrasive paper and similar articles provided with a coating,

in combination, the steps of dissolvin celluing, and bringing amoving paper web passlose ester in a solvent having a low oiling ing over a third cylinder in contact With the point, mixing the dissolved cellulose ester first cylinder, all the three cylinders rotating with an abrasive material, continuously inin the same direction, the mixture carried by 5 troducing the mixture into a space between the first cylinder being transferred to said 70 a first and a second cylinder, said space correpaper web. sponding to the desired thickness of the coat- CARL MUN CH.

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