Abstract: Washing methods of deinking secondary cellulose fiber (i.e., removing unwanted non-cellulose materials therefrom) are disclosed. These washing methods (as opposed to flotation methods) generally involve deinking the fiber with surface active agent (surfactant).The present invention utilizes a single foam-suppressing surface active agent consisting essentially ofR--(Ar)--(OC.sub.2 H.sub.4)m--(OC.sub.3 H.sub.6)n--Y;wherein R represents a monovalent higher aliphatic group containing from 6 to 24 carbon atoms,Ar represents an aromatic residue,--(OC.sub.2 H.sub.4)m--being a poly(ethylene oxide) chain,--(OC.sub.3 H.sub.6)n--being a poly(propylene oxide) chain;m is about 6 to about 15,n is about 12 to about 48,m:n is less than 1, andY is selected from the group consisting of hydroxyl and benzyl ether.The present washing method of deinking reduces or eliminates objectionable foam, potentially provides energy savings yet maintains or improves the quality of the deinked fiber.

Abstract: There is disclosed an improved process for phosphating asbestos fibers by reacting phosphorus chlorides with asbestos fibers in a first reaction vessel heated to a temperature within the range of the boiling temperature of the selected phosphorus chloride at atmospheric pressure and 200.degree. C. above the boiling temperature of said phosphorus chloride, then the phosphated asbestos fibers are cured in a second chamber and purged of any volatile by-product formed during the phosphating step. The products obtained possess reduced haemolytic activity.

Abstract: The novel, advantageous, and economical process of reclaiming printed waste paper comprises subjecting waste paper to a flotation de-inking process. The degree of whiteness of the reclaimed paper is considerably increased by the addition of specific phosphonic acid compounds to the de-inking bath. Hydroxy carboxylic acids, amino carboxylic acids, polycarboxylic acids as well as magnesium sulfate may also be added to the de-inking bath containing the phosphonic acids.

Abstract: Felted cellulosic sheet material is treated with a solution of an alkali al borohydride in order to improve and stabilize its strength and brightness. A subsequent wash with deionized water or preferably an aqueous solution containing an alkaline earth metal hydroxide, carbonate, or bicarbonate further improves the stability of the brightness and strength of felted cellulosic sheet material. The washing of cellulosic sheet material is most efficiently accomplished in an apparatus providing a means to add a metered amount of alkaline earth metal hydroxide, carbonate, or bicarbonate to a continuously flowing stream of wash medium.

Abstract: The present invention provdes an additive for reducing brightness loss upon pulp refining comprising in combination at least one anionic polymeric compound and at least one inorganic polymer, preferably such combinations wherein any of such anionic polymeric compounds are of low molecular weight. The preferred inorganic polyphosphates of such combination are those having average polymerization numbers of from about 10 to about 45. The weight proportion of inorganic polyphos-hate to anionic polymeric compound in such combination can be within the range of about 1:10::10:1.The present invention also provides pulp refining processes wherein such additive is added at a sufficient amount to the pulp material being refined to reduce brightness loss, such as at dosages of from about 0.0025 to about 0.5 weight percent additive actives to dry pulp, and end product pulps produced by such processes.

Abstract: A bleaching composition comprises sodium hydrosulfite, hexamethylenetetramine and a water soluble sulfite such as sodium sulfite or ammonium sulfite, or further a polyphosphate such as a pyrophosphate or a tripolyphosphate and is used in bleaching pulp with a good bleaching effect with no substantial hydrogen sulfide generation.

Abstract: There is disclosed chemically modified chrysotile asbestos fibers, more particularly phosphated asbestos fibers containing from 0.5 to 5% by weight of phosphate groups and heat treated phosphated asbestos fibers, both of which have an infrared spectrum which exhibits substantially no absorption within the range of 954-1080 cm.sup.-1. The novel phosphated asbestos fibers are characterized by reduced haemolytic and cytotoxic activities.

Abstract: A silver halides photographic material with improved keeping quality, said material having a substrate formed by coating a base web with a film-forming resin, preferably a polyolefin resin, said base web being composed principally of natural pulp or a mixture of two or more different types of natural pulp having a post color number of 2 or below, said post color number being defined by the following formula: ##EQU1## [wherein Ro is brightness (%).times.(1)/(100) before fading treatment, R is brightness (%).times.(1)/(100) after 18-hour fading treatment at 85.degree. C. and 95% RH, and P is post color (PC) number which indicates the degree (nondimensional number) of fading].

Abstract: Thermal insulating material of cellulosic fibers is prepared by treating wood chips or other fibrous cellulosic material with saturated steam at elevated temperatures and pressures and then fiberizing the treated material. A fire-retardant chemical is added to the material immediately prior to fiberization. The resulting fiberized cellulosic material when dried exhibits superior flame and fire resistance properties.

Abstract: The potassium compounds in heavy black liquor flowing in the recovery cycle are reduced by the introduction of magnesium nesosilicate to form magnesium potassium silicate which is voided from the system by filtration.

Abstract: A method of producing peroxide bleached pulp. Lignocellulose fiber material is impregnated with an aqueous silicate solution containing a sequestering agent. The impregnated lignocellulose is preheated with saturated steam at a temperature corresponding to the defibrating temperature to precipitate silic acid on and in the fibers. The preheated fiber mass is defibrated between two grinding disc in an atmosphere of saturated steam at a temperature of 100.degree.-170.degree. C. Alkaline peroxide solution free of silicate is introduced into the grinding space.

Abstract: Paper pulp is produced by a process in which raw sugar mill bagasse is moist depithed, wet bulk stored in the presence of an inorganic and organic preservative, wet depithed by hydraulic shearing in the presence of an inorganic color remover, pulped, washed, cleaned and dewatered.

Abstract: Fibrous material is pre-steamed, impregnated with alkali liquor, refined, and then oxygen pulped at a low consistency (about 3 to 8 percent solids) using an alkali liquor which contains boron compounds. The pulping step of the process is carried out in stages with recycle of liquor to preceding stages after it has been reoxygenated. By recycling a major portion of the pulping liquor, the actual liquor to fibrous material ratio at each stage of the pulping step is maintained at a relatively high level (12/1 to 30/1) while the effective liquor to fibrous material ratio for the overall process is much lower (4/1 to 8/1). This results in a bright pulp of acceptable strength as well as a high solids content spent liquor which is economically recoverable.

Abstract: A process is provided for the chemical refining of cellulose pulp which comprises, in sequence, the steps of:(1) impregnating the cellulose pulp with refining chemicals in an amount selected to effect chemical modification of the pulp;(2) adjusting the pulp consistency to within the range from about 30 to about 70%; and(3) passing the pulp in turbulent flow through an elongated reaction zone from one end to another end thereof in a gaseous atmosphere consisting essentially of steam and preferably containing less than 1% by volume of oxygen at a superatmospheric pressure within the range from about 5 to about 400 kPa and a temperature within the range from about 100 to about 150.degree. C. at which the chemical modification proceeds without a mechanical working sufficient to change the degree of beating of the pulp by more than about 2.degree.

Abstract: In aqueous peroxide-containing solutions used in bleaching of cellulose fiber, peroxide stability is very greatly increased by inclusion of alkali metal polyphosphate and alkali metal diethylene triamine penta(methylene phosphonate). Especially useful for addition of such stabilizers to the peroxide-containing solutions to increase such stability are essentially anhydrous compositions containing metal sequestering compounds comprising such polyphosphate and phosphonate in a weight ratio from about 10:1 to about 1:5.

Abstract: A method for increasing the final brightness of pulp contaminated with iron or manganese in a chlorine bleaching process of the type comprising one or more alkaline stages which comprises treating the pulp with at least 0.1 lbs. per ton of a water-soluble chelating agent.

Abstract: A process is provided for the acid bleaching of cellulose pulp with peroxides at a pH within the range from about -0.5 to about 3, followed immediately by aqueous alkaline extraction of the dissolvable lignin without intermediate washing.

Abstract: A method is provided for controlling the addition of active chemical for delignifying and/or bleaching cellulose pulp suspended in an aqueous liquor containing at least one chemical reactive with such active chemical, which comprises determining the amount of active chemical consumed by the chemical reactive with the active chemical in the liquor; adding the active chemical to the cellulose pulp suspension; and then after a predetermined time interval determining the amount of active chemical consumed by the chemical and cellulose pulp reactive with the active chemical in the liquor; from these determinations determining the amount of active chemical consumed by the pulp; and then carrying out the delignification and/or bleaching with an amount of active chemical adjusted according to the amount of active chemical consumed by the pulp.

Abstract: Method of producing mechanical pulp of improved brightness and light-scattering properties in a defibration apparatus in which wood chips are ground between a pair of discs which rotate relative to one another in a pressurized grinding zone. Prior to the defibrating process, the chips are impregnated with a solution of alkali, selected from the group consisting of sodium hydroxide, alkali silicate, alkali carbonate and alkali bicarbonate, and peroxide, surplus impregnating solution is removed from the chips by compression of the chips, the chips are introduced into a pressure vessel which is in communication with the grinding zone and compressed air is introduced into the pressure vessel in an amount sufficient to maintain the chips in the pressure vessel at a temperature below 90.degree. C. and to maintain superatmospheric pressure within the defibrating zone.

Abstract: A method for the regeneration of pulping or bleaching chemicals from spent liquor containing salts of polybasic organic acids. The liquor is evaporated and then burned so that organic matter will be discharged as carbon dioxide and water, and a carbonate residue is formed. Carbon dioxide is expelled from the carbonate with an acid by autocaustization to regenerate the cooking chemicals.

Abstract: An antifoam/defoam composition used also as a drainage aid in pulp and papermaking process lines which consists of a water-base composition useful in the pH range 7.0-9.0. The milieu in which the composition is utilized such as e.g. black liquor, may be kept at a pH of 4.0-12.0. The composition is as follows:Hydrophobic silicaBisamide of the following formula: ##STR1## where N IS AN INTEGER FROM 1 TO 6; ANDR is a saturated or unsaturated, straight or branched chain hydrocarbyl group having from 5 to 22 carbon atoms.Acid containing crosslinked copolymer of acrylic acidDioctyl sulfosuccinateParaffin oilWaterMore particular formulae are also set out below:______________________________________ (A) Hydrophobic silica 0-30% Ethylene-bis-stearamide .001-50% Acid containing crosslinked acrylic acid polymer .05-10% Dioctyl sulfosuccinate .05-10% Paraffin oil .001-99% H.sub.2 O .001-99% (B) Hydrophobic silica 4-12% Ethylene-bis-stearamide 4-12% Acid containing crosslinked acrylic acid polymer .

Abstract: Valuable amino alkane diphosphonic acids in which one or both hydrogen atoms of the amino group are substituted by hydroxy alkane groups, and their alkali metal salts and a process of using them are described. Said compounds are highly water-soluble, are stable against hydrolysis even at temperatures exceeding 100.degree. C., and have a high sequestering power so that they can be used advantageously, for instance, in processing aqueous media of considerable hardness, and in suppressing scale and corrosion in aqueous media used for heat treatment of containers.

Abstract: A process is provided for the delignification of lignocellulosic material wherein the lignocellulosic material, prior to the delignification, is treated with water or an aqueous solution to remove compounds which catalyze the degradation of carbohydrates and then the delignification is carried out with oxygen and alkali in the presence of a manganese compound to improve the selectivity of the delignification and increase the rate of delignification.

Abstract: The colored body content of the effluent from the alkali of a multi-stage cellulosic pulp bleach process is greatly reduced by extracting bleached cellulosic pulp with hypochlorite at a pH from about 6 to less than 9.

Abstract: The difficulties encountered in the manufacture of paper, cardboard, and other cellulosic articles, as they are caused by the formation of resinous or pitch deposits on the paper as well as on the paper machines and processing apparatus, are overcome, or at least considerably reduced, by the addition of phosphonic acids and more particularly of alkyl, amino or hydroxy alkyl, or cycloalkyl phosphonic acids or their alkali metal salts. If required, amino polycarboxylic acids, hydroxy carboxylic acids, or their alkali metal salts, or alkali metal polyphosphates are also added during processing.

Abstract: A process is provided for delignifying and bleaching cellulose pulp, which comprises carrying out the delignification and bleaching with oxygen and alkali in the presence of sodium bicarbonate, while removing carbon dioxide from the gas phase as required to maintain a carbon dioxide partial pressure within the range from about 0.001 to about 3 bars, thereby improving the selectivity of the delignification and bleaching.

Abstract: The difficulties encountered in the manufacture of paper, cardboard, and other cellulosic articles, as they are caused by the formation of resinous or pitch deposits on the paper as well as on the paper machines and processing apparatus, are overcome or at least considerably reduced, by the addition of phosphonic acids and more particularly of alkyl, amino or hydroxy alkyl, or cycloalkyl phosphonic acids or their alkali metal salts and of orthophosphoric acid or its alkali metal salts and/or of polyphosphoric acids. If required, amino polycarboxylic acids, hydroxy carboxylic acids, or their alkali metal salts, or alkali metal polyphosphates are also added during processing.

Abstract: A chemi-mechanical process for producing unbleached pulp with improved yields at high brightness including impregnating a lignocellulosic material in the form of wood chips with an alkaline solution containing an alkali metal borohydride in an amount over 0.1% by weight at a pH greater than 13, heating the impregnated chips at a temperature less than 150.degree. C to provide semi-cooked chips having a brightness in excess of 60 GE, and then defiberizing the semi-cooked chips to mechanically separate the fibers into an unbleached pulp having said brightness and a yield of at least 85%.

Abstract: An aqueous composition for bleaching wood pulp containing sodium hydrosulfite, and at least 2 weight percent hexamethylenetetramine based upon the weight of sodium hydrosulfite, wherein the solution has a pH between about 4 and about 11. The hexamethylenetetramine prevents hydrogen sulfide formation during bleaching of the wood pulp.