Abstract: A method of de-inking wastepaper by pulping the paper in the presence of an enzyme is disclosed. The enzyme dislodges the ink particles from the paper fibers. The preferred enzymes are the acid resistant carbohydrases. The de-inking medium is an aqueous solution of the enzyme, preferably maintained at a pH less than about 7 and at a temperature between about 20° C. and about 60° C. No conventional chemical de-inking agents are required. The dislodged ink particles may be removed by any conventional method, such as flotation or washing.

Abstract: The present invention relates to a modified enzyme and its modification process and more particularly, to the modified enzyme and its modification process, wherein amine group (—NH2) from amino acid residues of cellulose or hemicellulase, carbohydrase, is covalently coupled with the hydroxy and group (—OH) of polyoxyethylene fattyalcoholether expressed by the following formula 1 and then the modified enzyme exhibits a high stability of activities against pH and temperature as well as better enzyme activity. RO—(CH2CH2O)n—H   (1) Where, R is an alkyl group of 14 to 18 carbon atoms, and n is an integer of 3 to 12.

Abstract: The present invention relates to a method for recycling of old corrugated container (OCC) using flotation and kneading treatment and more particularly, to a method for recycling of OCC, wherein OCC is treated withflotation and kneading, treatment, and thereby removing fines and ink spot in the waste pulp and improving the strength and drainage property. As a result, it can be recycled similar to the expensive virgin unbleached kraft pulp.

Abstract: The present invention relates to a method for recycling of old corrugated container (OCC) using flotation, followed by selective enzymatic treatment to fines portion and by selective refining to long fiber stream, and more particularly, to a method for recycling of OCC, wherein OCC is treated with floatation and enzymatic hydrolysis and those recycled stock is refined, thereby having the following effects:a) The drainage property of base paper of old corrugated container is improved; andb) The strength of the same is enhanced by the refining treatment of the fractionated long fiber only; andc) The cost for disintegration and enzymatic treatment is reduced; and(d) The imported corrugated board and unbleached kraft pulp can be substituted by the Korean old corrugated container (KOCC).

Abstract: A method of de-inking wastepaper by pulping the paper in the presence of an enzyme is disclosed. The enzyme dislodges the ink particles from the paper fibers. The preferred enzymes are the acid resistant carbohydrases. The de-inking medium is an aqueous solution of the enzyme, preferably maintained at a pH less than about 7 and at a temperature between about 20.degree. C. and about 60.degree. C. No conventional chemical de-inking agents are required. The dislodged ink particles may be removed by any conventional method, such as flotation or washing.

Abstract: The present invention relates to retention aids for papermaking, in particular which comprise cationic multiarmed star-like polymers of formula (I):(D).sub.y --(A).brket open-st.B--(CH.sub.2).sub.n --(E).sub.p --(F).sub.q .brket close-st..sub.x (I)as an effective component to improve the retention of fines fraction by structural characteristics of multiarmed polymer chains connected with one starting point on the compound. In formula (I), A is ##STR1## B is --O-- or --COO--; D is --OH; E is ##STR2## F is ##STR3## wherein, R.sup.1 --R.sup.11 are independently hydrogen or alkyl; R.sub.a --R.sub.d are independently hydrogen or alkyl; X.sup.- is ##STR4## x is an integer selected from 3 to 24; y is an integer selected from 0 to 21; n is an integer selected from 3 to 6; p is an integer selected from 300 to 4000; and q is an integer selected from 0 to 1000.