Abstract: The present invention is directed to a deinking agent with which a high-quality pulp sheet having a low Eric number can be obtained.The deinking agent for wastepaper reclamation comprises (a) an alkylene oxide adduct of an ester prepared from a dimer acid and/or polymer acid obtained from an unsaturated fatty acid having a specific number of carbon atoms, and an alcohol having a specific number of carbon atoms at a specific molar ratio, and (b) a higher fatty acid and/or higher fatty acid soap having a specific number of carbon atoms, provided that the (a)/(b) weight ratio is 95/5 to 60/40.

Abstract: A deinking method which comprises adding a specified nonionic surfactant having a specified solubility parameter as an essential component, during in the pulping step (the preceding step) and in any of the subsequent steps (the succeeding step). By use of the deinking surfactant composition and the deinking method of the present invention, an excellent deinking performance, including an elevated whiteness, a decrease in the number of unliberated large ink spots and an improved defoaming property of the flotation reject, can be achieved in deinking waste papers, in particular, waste OA papers and blends containing thereof.

Abstract: A deinking composition which comprises a specified nonionic surfactant having a specified solubility parameter as an essential component.A deinking method which comprises adding the above-described deinking composition during in the pulping step (the preceding step) and in any of the subsequent steps (the succeeding step).By use of the deinking composition and the deinking method of the present invention, an excellent deinking performance, including an elevated whiteness, a decrease in the number of unliberated large ink spots and an improved defoaming property of the flotation reject, can be achieved in deinking waste papers, in particular, waste OA papers and blends containing thereof.

Abstract: The removal of hydrophilic flexographic inks from a pulp fiber slurry in a flotation or flotation/wash deinking system is accomplished by using a combination of (a) a fatty acid or salt thereof, (b) a rosin acid or salt thereof, and (c) a non-ionic or anionic surfactant along with water having a hardness of about 80 to 500 ppm Ca.sup.+2.

Abstract: The removal of inks, particularly hydrophilic flexographic inks, from a pulp fiber slurry is accomplished by use of a combination of (a) a non-ionic surfactant; (b) a fatty acid or salt thereof; and (c) a water-soluble cationic polymer having a molecular weight less than about 1,000,000 daltons, particularly a polymer derived from the reaction of epichlorohydrin and at least one diamine or the polymerization of aziridine.

Abstract: A deinking agent for regenerating waste paper, which comprises a reaction product obtained by reacting a compound having an OH group, which is represented by the following (A) or (B) with a dicarboxylic acid or an anhydride thereof as an active ingredient:(A) a compound obtained by adding ethylene oxide and propylene oxide to a higher fatty acid having 8 to 22 carbon atoms in such a manner as to control the molar ratio of ethylene oxide/propylene oxide to from 1 to 4 and to control the total amount of the added ethylene oxide and propylene oxide to from 10 to 50 moles on average; or(B) an incomplete ester of a polyhydric alcohol, to which ethylene oxide and propylene oxide have been added in such a manner as to control the molar ratio of ethylene oxide/propylene oxide to from 1 to 4 and to control the total amount of the added ethylene oxide and propylene oxide to from 10 to 50 moles per OH group on average, and a higher fatty acid having 8 to 22 carbon atoms;is disclosed.

Abstract: A deinking composition for use in the reclamation of waste paper consisting essentially of a mixture of higher fatty acids having 8 to 24 carbon atoms, or salts thereof, wherein the average carbon atom number of said fatty acids in said mixture ranges from 12.7 to 21.5, and wherein the content of higher fatty acids having 20 to 24 carbon atoms or salts thereof, ranges from 9.6 to 70.6% by weight, said mixture having an iodine value (IV) of not greater than 45.

Abstract: A deinking agent comprising an ester mixture as the active ingredient, wherein the ester mixture is obtained by adding ethylene oxide and propylene oxide to a mixture obtained by reacting a natural fat or a reaction product, obtained by preliminarily reacting a natural fat with glycerol, with a monohydric or dihydric alcohol in such a manner as to give a molar ratio of the alcohol to the glycerol in the natural fat of from 0.02/1 to 1/1. By using the deinking agent of the present invention, a less sticky deinked pulp can be obtained without any foaming troubles or dulling.

Abstract: A deinking composition comprising a deinking agent which is a reaction product obtained by:(a) reacting (i) a natural oil or a fat or a reaction product of a natural oil or a fat with glycerine, with (ii) a hexahydric alcohol, wherein the molar ratio of said hexahydric alcohol and glycerine moiety in said natural oil and fat is in the range of between 0.05/1-0.48/1, to obtain an ester mixture having a hydroxyl group value (OHV) of 18-220; and(b) reacting said ester mixture with ethylene oxide and propylene oxide wherein the molar ratio of ethylene oxide to propylene oxide is in the range of between 1.8 and 2.2, and the average mole number of added ethylene oxide is in the range of between 30 and 300, based on the mole number of glycerides present.

Abstract: A deinking composition comprising a reaction product of a glyceride mixture, derived from natural oil and fat with ethylene oxide and propylene oxide. The glyceride mixture comprises 5 to 10 percent by weight of monoglycerides, 30 to 45 percent by weight of diglycerides and 50 to 70 percent by weight of triglycerides. The reaction product has a molar ratio of ethylene oxide to propylene oxide in the range of 1.8 to 2.2 and has, on average, from 30 to 80 moles of added ethylene oxide per mole of glycerides.