DE165997C - - Google Patents

Description

fm

c tl \ Γα mc

fttafec 23.

IMPERIAL

PATENT OFFICE.

, © cfien

CLASS 39 />.

Obtaining the best gutta-percha and balata is still in the way operated that the sap is extracted from the bark after the tree has been felled. This is a Procedure; which rightly suggests fears that the valuable material will soon is withdrawn from trade more and more. Therefore attempts have been made for about ten years made the gutta-percha instead of just out

to extract branches and leaves of the tree from the branches of the trunk.

Extraction processes are used for this purpose, in which the various Solvents for gutta are used. These are carbon disulfide, toluene, resin oil, petroleum ether and the like.

The difficulty of working in the tropical areas with such low boilers Liquids and the high transport costs make isolating the gutta etc. at the point of extraction not worthwhile. the Transport costs for branches and leaves to our area for processing purposes also make the material more expensive.

It is far more disturbing that the extractants used are removed from the raw material dissolve the soluble resinous substances at the same time; this is known to affect the most important property of gutta-percha, the ability to insulate, to a large extent. For this reason, the gutta-percha obtained in this way is not included into industry.

One was therefore forced to use the Guttaj percha solutions or the dry residues same by failures respectively. to clean again undressing with resin solvents. According to the method of brit, patent specification j 19728 from 1897, the Pfianzenteile Treated with alkalis prior to extraction with toluene, which facilitates the extraction and leaves the resins in the residue should stay. In this case, however, it was not recognized that the insulation was can be achieved through treatment with alkalis alone.

According to the method of patent specification 109802, the lignified parts of the Leaves and branches of the gutta trees etc. loosened up around them by all sorts of means later to be completely destroyed by the action of microorganisms. In this procedure there is also an intermediate stage, with softer the leaves etc. with a very thin sodium bicarbonate solution heated under pressure to remove impurities.

In contrast to all this acquaintance, it has now been found that the Gutta-percha and balata from the plant parts in the highest yield and good purity to gain if one uses only dilute solutions of caustic alkalis or normal carbonated alkalis treated. One proceeds, for example, that the coarsely chopped, crushed or powdered leaves

Claims (1)

with three times the weight of an im- «Danger of four percent caustic soda in one Boiler up to a pressure of about 5 atm. heated. When the boiler is opened it floats the gutta-percha as a solid, only slightly contaminated by other admixtures Cake on the surface of the jar. The gutta-percha is then skimmed off and used for Removal of the adhering lye with boiled water or on the known Wash rollers washed out. The plant remains are at the bottom of the container. In this way, up to 100 kg of leaves depending on the quality of the same 12 kg of a low-resin gutta-percha can be obtained. This yield corresponds to the known information. Obach, for example, in his work "The Gutta-Percha" on p. 53 denotes it Content of gutta-percha in the plant parts ao on c) up to 10 percent. 997 The present process has the advantage of simplicity of apparatus and cheapness over all previously known. Ρλ τ ε ν τ - A ν s γ κ υ c η: Process for obtaining gutta-percha and balata from leaves and pieces of wood the trees and bushes supplying these substances, characterized by that these with thin solutions of caustic alkalis or normal carbonate alkalis be heated under moderate pressure until the gutta-percha melts respectively Balata has emerged from the wooden parts and, due to its low specific weight, is on the surface the applied alkali has collected, so that a treatment with any solvents for gutta-percha or Balata is made dispensable. 4t