US1833852A - Manufacture of paper making material - Google Patents

Description

Patented Nov. 24,; 1931 j arse STATES.

Arum-forms,

'10 K WATANABB, OI KA GOYA, JEAN mama or urea No Drawing. Application fled llovcniber I, 1888, Serial 1T0. 404,210,,and in Japan January 23, 1989;

This invention relates to im rovements in the manufacture of paper ma g in order to recover pulp by deinking of old printed paper.

. The characteristic feature of this invention is to make an emulsion of camphor oil, a

solvent of printing ink and dry printing ink, by the action of suitable dispersing medium such as soap solution, and to mix the resultant emulsion of oamph or oil with old printed aper treated'with alkali and thereby de-ink y the dissolution and dispersion of ink mat ter into the said dispersed solvent oil.

The object of this invention is to attain the 1 deinking of old printed paper easily and completely so it can recover a useful paper mak- -1ng material having the same grade to that of the old paper used by a simple and economical process.

Heretofore old "printed paper has not been utilized as 'araw material'for the recovery of high grade paper pulp on account of the difiiculty of 'deinking. v But, by the improved method of this invention this .old printed paper may be satisfactorily used as a raw material for the same purpose, and also a successful utilization of such waste matter as old printed paper can'be attained, of which there is an immense supply. I

This invention is preferably carried out as follows: To make an emulsion of camphor oil a solution of soap made of any sort of The next treatment is the tearing-0r breaking up of old printed paper. For this tearing a paper making kneaderis used, and for about 1,000 lbs. of the quantity of old paper the aforesaid emulsion of camphor oil to-' gether with about 3 lbs. of caustic soda solution and a proper quantity of. water are poured down into the kneader through re-.

spective supply pipes provided at the charging'part of the kneader. In kneading of this 7 .is then poured down into the paper making tcher or the mixer and in this apparatus t is agitated by a constant rotation for about tillirty minutes. During this agitation in t e fi xe on old printed paper is completely peptized into minute particles, and as a result of,this the pigment most contained in printsuspended in the dispersed solvent oil. This dispersed mixture, therefore, contains minute particles 'ofpeptized ink matter so that if this (potcher or the mixer dry printing ink ing ink such as lamp black is also completely mixture is scooped up and pressed in the hands there will be separated a blackish muddy liquor from the mixture and a white paper fibre will remain in the hands. From this experiment it is clearly known that pigments and other constitutents of printing ink are completely peptized into very minute particles in. the dispersed solvent oil so as to be capable of free passing through filter paper of the qualitative analysis.

The aforesaid strong peptization of dry 1 printing ink (containing pigment, varnish etc.) fixed on old printed paper by the action of dispersed solvent oil comprising a mixture explained as below.

Camphor oil, in general, is a good solvent of dry varnish in printing ink, and if camphor oil is added to old printed paper in a form of emulsion there can be attained the result of filling the paper with camphor oil in a great volume. When varnish in ink is disof emulsion and caustic soda solution, will be solved in the dispersed solvent oil it then forms a colloidal varnish, and as it is a substance easily emulsified by soap solution varnish once dissolved in camphor oil it now begins to separate from the solution in a form of colloid by the aid of agitating orstirring action and at the same time the dissolving action of remaining varnish into solvent oil is again proceeded. v

Moreovercam-phor oil has the property of dissolving rosin present in old printed paper, and therefore it greatly weakens. the chemical afiinity between varnish and rosin by its presence resulting in the separation of varnish and rosin.

The soap solution itself, at the same time causes a peptizing action of varnish and rosin in the kneaded paper.

Caustic soda, on the other hand, is utilized toneutralize acidity derived from acid materials in paper such as sulphuric acid in and dispersing the ink matter in the said dispersing medi T h Ira witness whereof I have hereunto set my NAOSHIGE OSAWA.

alum-cake, alum and sizing materials such as rosin, and thus it can prevent the emulslon from its coagulation by acid and keeping the emulsion in good stability. Moreover caustic soda solution acts to excite the pe tization of varnish and rosinin paper, sot at by this action size of paper is destroyed and the'chemical afiinity between, water and fibre can be promoted, while the chemical aflinity between varnish, fibre and rosin being remarkably weakened. A greater part of black muddy liquor, which is completely peptized during the agitation in the potcher or the mixer, may be separated by using an apparatus such as centrifugal separator. The remaining fibre of paper thus gained is then poured into the potcher or the mixer with water. Thereupon it is repeatedly washed by the drum washer or it may be poured down into a tank having a mat stretched over its bottom and provided with agitators and in this tank the muddy liquor now becomes filtered and separated.

In actual practice of this washing process there rarel appear minute black spots on the washed pu p mixture-even when its quantity is very small. But these spots will completely vanish by washing and adding a small quantity of alkali, as the said phenomena of black spots appearing is chiefly due to lack of the alkalinity of the kneeded paper mixture. Moreover this vanishing efiect 1s better attained when a small quantity of soap is added with alkali- The resultant product after the washing is completely deinked and the fibre has the same quality as that of the fibre consisting of old printed paper, can be obtained.

' The produced material thus gained is then printing ink bythe action of soap solution as dispersing medium, then mixing the resultant emulsion with old printed paper. 'pneviay treated with an alkaliand finally detheold printed paper by dissolving