Classifications

• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
  • D21H17/20—Macromolecular organic compounds
  • D21H17/21—Macromolecular organic compounds of natural origin; Derivatives thereof
  • D21H17/24—Polysaccharides
  • D21H17/28—Starch
  • D21H17/29—Starch cationic
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
  • D21H17/20—Macromolecular organic compounds
  • D21H17/33—Synthetic macromolecular compounds
  • D21H17/34—Synthetic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
  • D21H17/41—Synthetic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds containing ionic groups
  • D21H17/44—Synthetic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds containing ionic groups cationic
  • D21H17/45—Nitrogen-containing groups
  • D21H17/455—Nitrogen-containing groups comprising tertiary amine or being at least partially quaternised
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
  • D21H17/20—Macromolecular organic compounds
  • D21H17/21—Macromolecular organic compounds of natural origin; Derivatives thereof
  • D21H17/24—Polysaccharides
  • D21H17/28—Starch
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H5/00—Special paper or cardboard not otherwise provided for
  • D21H5/26—Special paper or cardboard manufactured by dry method; Apparatus or processes for forming webs by dry method from mainly short-fibre or particle material, e.g. paper pulp
  • D21H5/265—Treatment of the formed web
  • D21H5/2657—Consolidation
  • D21H5/2664—Addition of a binder, e.g. synthetic resins or water
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
  • D21H17/20—Macromolecular organic compounds
  • D21H17/33—Synthetic macromolecular compounds
  • D21H17/34—Synthetic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
  • D21H17/41—Synthetic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds containing ionic groups
  • D21H17/44—Synthetic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds containing ionic groups cationic
  • D21H17/45—Nitrogen-containing groups
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
  • D21H21/14—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties characterised by function or properties in or on the paper
  • D21H21/18—Reinforcing agents

Definitions

• the graft polymerization is preferably carried out in the presence of a redox catalyst.
• a process for cationizing starch is known from US Pat. No. 4,097,427, in which the starch is boiled in an alkaline medium in the presence of water-soluble quaternary ammonium polymers and an oxidizing agent.
• Quaternary ammonium polymers include quaternized diallyldialkylamine polymers or quaternized polyethyleneimines are also suitable.
• the oxidizing agent used is, for example, ammonium persulfate, hydrogen peroxide, sodium hypochlorite, ozone or tert-butyl hydroperoxide.
• the modified cationic starches which can be prepared in this way are added to the paper stock as dry strength agents in the production of paper. However, the wastewater is polluted by a very high COD value.
• the invention has for its object to achieve an improvement in the dry strength of paper when using starch compared to the known methods.
• the substantivity of the starch is increased when it is drawn onto the fibers in the paper stock, thereby reducing the COD load in the wastewater.
• the mixtures to be used as dry strength agents according to the invention have good retention towards paper fibers in the paper stock.
• the COD value in the white water is significantly reduced with the mixtures according to the invention compared to the native starch.
• the interfering substances contained in the water circuits of paper machines affect the effectiveness of the dry strength agents to be used according to the invention only slightly.
• the pH of the pulp suspension can be in the range from 4 to 9, preferably 6 to 8.5.
• the modified starch to be used according to the invention is produced in the absence of oxidizing agents, polymerization initiators and also in the absence of alkali.
• the modification of the native potato starch is preferably achieved by heating it in aqueous slurry with the cationic polymers in question to a temperature above the gelatinization temperature of the native potato starch.
• the gelatinization temperature of the starch is the temperature at which the birefringence of the starch grains is lost, cf. Ullman's Encyclopedia of Technical Chemistry, Urban and Schwarzenberg, Kunststoff-Berlin, 1965, 16th volume, page 322.
• the modification of the native potato starch can generally be done in various ways.
• An already digested native potato starch which is in the form of an aqueous solution, can be reacted with the cationic polymers in question to temperatures in the range from 15 to 70 ° C. Longer contact times are required at even lower temperatures. If the reaction is carried out at even higher temperatures, e.g. up to 110 ° C, shorter contact times are required, e.g. 0.1 to 15 min.
• the simplest way of modifying the native potato starch is to heat an aqueous slurry of the starch in the presence of the cationic polymers in question to a temperature above the gelatinization temperature of the native potato starch.
• the starch for modification is heated to temperatures in the range from 70 to 110 ° C., the reaction being carried out in pressure-tight apparatus at temperatures above 110 ° C.
• the starch is always solubilized in the absence of oxidizing agents, initiators and alkali in about 3 minutes to 5 hours, preferably 5 to 30 minutes. Higher temperatures here require a shorter dwell time.
• aqueous phase of the reaction mixture increases.
• a 3.5% by weight aqueous solution of the mixture to be used as dry strength agent has viscosities in the range from 50 to 10,000 mPas (measured according to Brookfield at 20 rpm and 20 ° C.).
• (A) Polymers of diallyldimethylammonium chloride are suitable for the preparation of the dry strength agents to be used according to the invention. Polymers of this type are known. Under Polymers of diallyldimethylammonium chloride should primarily be understood to mean the homopolymers and the copolymers with acrylamide and / or methacrylamide. The copolymerization can be carried out in any monomer ratio.
• the K value of the homopolymers and copolymers of diallyldimethylammonium chloride is at least 30, preferably 95 to 180.
• the substituent X ⁇ in the formulas I and II can in principle be any acid residue of an inorganic and an organic acid.
• the monomers of formula I are obtained by using the free base, i.e. 1-vinyl-2-imidazoline, neutralized with the equivalent amount of an acid.
• the vinylimidazolines can also be neutralized, for example, with trichloroacetic acid, benzenesulfonic acid or toluenesulfonic acid.
• quaternized 1-vinyl-2-imidazolines can also be used.
• quaternizing agents are, for example, C1 to C18 alkyl chlorides or bromides, benzyl chloride, benzyl bromide, epichlorohydrin, dimethyl sulfate and diethyl sulfate. Epichlorohydrin, benzyl chloride, dimethyl sulfate and methyl chloride are preferably used as quaternizing agents.
• the compounds of the formula I or II are preferably polymerized in an aqueous medium.
• the copolymers are obtained by using the monomers of the compound of the formulas I and II with acrylamide and / or methacrylamide polymerized.
• the monomer mixture used in the polymerization contains at least 1% by weight of a monomer of the formula I or II, preferably 10 to 40% by weight.
• Copolymers of 60 to 85% by weight of acrylamide and / or methacrylamide and 15 to 50% by weight of N-vinylimidazoline or N-vinyl-2-methylimidazoline are particularly suitable for modifying native potato starch.
• the copolymers can also by copolymerizing other monomers, such as styrene, vinyl acetate, vinyl propionate, N-vinylformamide, C1- to C4-alkyl vinyl ether, N-vinylpyridine, N-vinylpyrrolidone, N-vinylimidazole, acrylic acid esters, methacrylic acid esters, ethylenically unsaturated C3- to C5 -Carboxylic acids, sodium vinyl sulfonate, acrylonitrile, methacrylonitrile, vinyl chloride and vinylidene chloride can be modified in amounts up to 25% by weight.
• other monomers such as styrene, vinyl acetate, vinyl propionate, N-vinylformamide, C1- to C4-alkyl vinyl ether, N-vinylpyridine, N-vinylpyrrolidone, N-vinylimidazole, acrylic acid esters, methacrylic acid esters
• polymerization in aqueous solution it is possible, for example, to prepare the homopolymers and copolymers in a water-in-oil emulsion.
• the monomers can also be polymerized by the reverse suspension polymerization method, in which bead-like polymers are obtained.
• the polymerization is initiated with the aid of conventional polymerization initiators or by the action of high-energy radiation.
• Suitable polymerization initiators are, for example, hydrogen peroxide, inorganic and organic peroxides, and hydroperoxides and azo compounds. Mixtures of polymerization initiators can be used as well as so-called redox polymerization initiators, e.g.
• the polymerization is carried out at temperatures in the range from 0 to 100 ° C., preferably 15 to 80 ° C. It is of course also possible to polymerize at temperatures above 100 ° C., but it is then necessary to carry out the polymerization under pressure. For example, temperatures up to 150 ° C are possible.
• the reaction time depends on the temperature. The higher the temperature during the polymerization, the shorter the time required for the polymerization.
• copolymers of compounds of the formula I with acrylamide or methacrylamide are preferably used as cationic polymers of group (c) for economic reasons. These copolymers then contain the compounds of the formula I only in effective amounts, ie in an amount of 1 to 40% by weight.
• the dry strength agents to be used according to the invention can be used in the production of all known paper, cardboard and cardboard qualities, for example writing paper, printing paper and packaging paper.
• the papers can be made from a variety of different types of fiber materials, for example from sulfite or sulfate pulp in the bleached or unbleached state, wood pulp, waste paper, thermomechanical material (TMP) and chemothermomechanical material (CTMP).
• TMP thermomechanical material
• CTMP chemothermomechanical material
• the pH of the stock suspension is between 4.0 and 10, preferably between 6.0 and 8.5.
• the dry strength agents can be used both in the production of base paper for papers with low basis weight (LWC papers) and for cardboard.
• the basis weight of the papers is between 30 and 200, preferably 35 and 150 g / m2, while it can be up to 600 g / m2 for cardboard.
• the paper products produced according to the invention have a noticeably improved strength compared to such papers which were produced in the presence of an equal amount of native potato starch, which strength can be quantified, for example, on the basis of the tear length, the burst pressure, the CMT value and the tear resistance.
• the parts given in the examples are parts by weight, the percentages relate to the weight.
• the viscosities of the solidifiers were determined in an aqueous solution at a solids concentration of 3.5% by weight and a temperature of 20 ° C. in a Brookfield viscometer at 20 rpm.
• the sheets were made in a Rapid-Köthen laboratory sheet former.
• the dry tear length was determined according to DIN 53 112, sheet 1, the dry burst pressure according to Mullen, DIN 53 141, the CMT value according to DIN 53 143 and the tear propagation resistance according to Brecht-Inset according to DIN 53 115.
• the leaves were tested after 24-hour air conditioning at a temperature of 23 ° C and a relative humidity of 50%.
• a 3% slurry of native potato starch (gelatinization temperature 90 ° C.) in water is mixed with such an amount of polymer 1 that the resulting mixture contains 10% polymer 1, based on the native potato starch used.
• the mixture is then heated with stirring to a temperature in the range from 90 to 95 ° C. for 15 minutes and, after cooling to a temperature in the range from 10 to 40 ° C., is used according to the invention as a dry strength agent for paper by placing it in a stock suspension before Sheet formation admits (viscosity: 656 mPa ⁇ s).
• a dry strength agent for paper is prepared by reacting a 3% aqueous slurry of native potato starch with polymer 2 instead of polymer 1 used there (viscosity: 870 mPa ⁇ s).
• a dry strength agent for paper is produced by using polymer 3 instead of polymer 1 described there (viscosity: 950 mPa ⁇ s).
• a dry hardening agent is prepared by using polymer 4 instead of the polymer used there (viscosity: 398 mPa ⁇ s).
• a 3% aqueous slurry of native potato starch (gelatinization temperature 90 ° C) is heated with stirring for 15 minutes to a temperature in the range from 90 to 95 ° C, the starch dissolving. After the starch solution has cooled to a temperature of 70 ° C., a 5% aqueous solution of polymer 2 is added, so that the amount of the polymer, based on the native potato starch, is 10%. The mixture is then stirred for a further 10 minutes at a temperature of 70 ° C. and then cooled to room temperature. A dry strength agent for paper is obtained (viscosity: 784 mPa ⁇ s).
• a dry hardening agent is produced by using polymer 5 instead of the polymer used there (viscosity: 250 mPa ⁇ s).
• a dry hardening agent is produced by using polymer 6 instead of the polymer used there (viscosity: 150 mPa ⁇ s).
• a dry hardening agent is produced by using polymer 7 instead of the polymer used there (viscosity: 206 mPa ⁇ s).
• a dry hardening agent is produced by using polymer 8 instead of the polymer used there (viscosity: 86 mPa ⁇ s).
• a dry strength agent for paper is produced according to the specification given under hardener 1, but polymer 9 is used instead of the polymer used there (viscosity: 766 mPa ⁇ s).
• a dry strength agent for paper is made according to the method described in US Pat. No. 4,097,427 in Example 7 using Polymer 3 in an amount of 6.6% based on starch, 5% sodium hydroxide based on starch and ammonium persulfate produced as an oxidizing agent (viscosity: 30 mPa ⁇ s).
• a dry strength agent for paper is prepared by using polymer 3 instead of polymer 1 described there, in such an amount that the resulting mixture is now only 6.6% polymer instead of 10% 3, based on starch, contains (viscosity: 985 mPa ⁇ s).
• a dry hardening agent is produced by using native corn starch instead of the native potato starch used there (viscosity: 290 mPa ⁇ s).
• a dry hardening agent is produced by using native wheat starch instead of the native potato starch used there (viscosity: 220 mPa ⁇ s).
• Sheets with a weight of 120 g / m2 are produced in a Rapid Köthen sheet former.
• the paper stock consists of 80% mixed waste paper and 20% bleached beech sulfite pulp, which is ground to 50 ° SR (Schopper-Riegler) and to which the solidifier 1 described above is added in an amount such that the solids content of solidifier 1, based on dry Paper stock, 2.2%.
• the pH of the stock suspension is adjusted to 7.6.
• the leaves made from this fabric model are air-conditioned and then the CMT value, the dry burst pressure and the dry tear length are measured using the methods specified above. The results are shown in Table 1.
• Example 1 is repeated in each case with the exception that the hardeners given in Table 1 are used instead of the hardeners 1 used in Example 1. The results thus obtained are shown in Table 1.
• Example 1 is repeated without adding a dry strength agent, ie a fabric made from 80% mixed waste paper and 20% bleached beech sulfite pulp, which is ground to 50 ° SR, is dewatered in a Rapid-Köthen sheet former, whereby sheets with a basis weight of 120 g / m 2 are obtained.
• a dry strength agent ie a fabric made from 80% mixed waste paper and 20% bleached beech sulfite pulp, which is ground to 50 ° SR, is dewatered in a Rapid-Köthen sheet former, whereby sheets with a basis weight of 120 g / m 2 are obtained.
• a dry strength agent ie a fabric made from 80% mixed waste paper and 20% bleached beech sulfite pulp, which is ground to 50 ° SR
• Comparative example 1 is repeated with the exception that 2% native potato starch, based on dry fiber material, is added to the paper stock.
• the strength values of the paper sheets thus obtained are given in Table 1.
• Example 1 is repeated with the exception that the strengthening agent described therein is replaced by the same amount of strengthening agent 10.
• the strength values of sheets thus obtained are given in Table 1.
• Example 1 is repeated with the exception that the dry strength agent indicated therein is replaced by the same amount of the strength agent 11.
• the strength values of paper sheets produced in this way are given in Table 2.
• Example 1 is repeated with the exception that the strengthening agent described therein is replaced by the same amount of strengthening agent 12.
• the strength values of sheets thus obtained are given in Table 2.
• Example 1 is repeated with the exceptions that the strengthening agent described therein is replaced by the same amount of strengthening agent 12 and that instead of the paper stock consisting of 80% mixed waste paper and 20% bleached beech sulfite pulp, a paper stock made of 100% unbleached coniferous wood sulfate is used , which is ground to 30 ° SR (Schopper-Riegler), and the sheets formed from it have a basis weight of 100 g / m2.
• the strength values of these sheets are given in Table 3.
• Example 1 is repeated with the exceptions that the strengthening agent described therein is replaced by the same amount of strengthening agent 11 and that instead of the paper stock consisting of 80% mixed waste paper and 20% bleached beech sulfite pulp, a paper stock made of 100% unbleached coniferous wood sulfate is used , which is ground to 30 ° SR (Schopper-Riegler), and the sheets formed from it have a basis weight of 100 g / m2.
• the strength values of these sheets are given in Table 3.
• Comparative Example 1 is repeated with the exception that instead of the paper stock consisting of 80% mixed waste paper and 20% bleached beech sulfite pulp, a paper stock made of 100% unbleached coniferous wood sulfate, which is ground to 30 ° SR (Schopper-Riegler), is used for sheet formation and forms sheets with a basis weight of 100 g / m2.
• SR Schopper-Riegler
• Paper with a basis weight of 120 g / m 2 and a width of 68 cm is produced on a test paper machine at a speed of the paper machine of 50 m / min.
• 80% mixed waste paper and 20% bleached sulfite pulp with a freeness of 50 ° SR are used as paper stock.
• hardener 1 is added in an amount of 2.2%, based on dry paper stock.
• the white water has a pH of 7.6.
• the strength values of the paper thus produced are given in Table 4.
• Example 12 is repeated with the exception that the same amount of hardener 3 is used.
• the strength values of the paper so produced are given in Table 4.
• Example 12 is repeated with the exception that instead of the dry strength agent used there, the hardener 4 is used.
• the strength values of the paper thus obtained are given in Table 4.
• Example 12 is repeated with the exception that the solidifying agent 6 is used instead of the dry hardening agent used there.
• the strength values of the paper thus obtained are given in Table 4.
• paper with a basis weight of 120 g / m 2 is produced from a paper stock which consists of 80% mixed waste paper and 20% bleached beech sulfite pulp with a freeness of 50 ° SR.
• the speed of the paper machine is set to 50 m / min, the pH value of the white water is 7.6.
• the difference to example 12 is that no dry strength agent is used.
• the strength values of the paper thus obtained are given in Table 4.
• Comparative Example 7 is repeated with the exception that 2% native potato starch, based on dry fiber, is additionally added to the paper stock described there before dewatering.
• the strength values of the paper thus obtained are given in Table 4.
• Comparative example 7 is repeated with the exception that 2% native corn starch, based on dry fiber, is additionally added to the paper stock described there before dewatering.
• the strength values of the paper thus obtained are given in Table 4.
• Comparative Example 7 is repeated with the exception that 2% native wheat starch, based on dry fiber, is additionally added to the paper stock described there before dewatering.
• the strength values of the paper thus obtained are given in Table 4.
• Example 12 is repeated with the exception that the same amount of hardener 13 is used instead of hardener 1.
• the strength values of the paper thus obtained are given in Table 4.
• Example 12 is repeated with the exception that the same amount of hardener 14 is used instead of hardener 1.
• the strength values of the paper thus obtained are given in Table 4.
• an LWC paper is produced from the following fabric model: 40% bleached wood pulp, 30% bleached softwood sulfite pulp and 30% bleached birch sulfate pulp with a grinding degree of 35 ° SR. Based on dry fibrous material, 20% china clay and 0.3% of a commercially available cationic polyacrylamide with a K value of 120 are added in the form of a 7% aqueous solution. In addition, 0.5% alum is added so that the water running off the sieve has a pH of 6. Before the dewatering on the paper machine sieve, hardener 1 is added in an amount of 2.2%, based on dry pulp. At a production speed of the paper machine of 60 m / min, paper with a basis weight of 50 g / m 2 is obtained, the strength values of which are given in Table 5.
• Example 16 is repeated with the exception that the same amount of hardener 2 is used instead of the hardener used there.
• the dry strength values of the paper thus obtained are given in Table 5.
• Example 16 is repeated with the exception that instead of the hardener stated there, hardener 4 is now used.
• An LWC paper is obtained, the dry strength values of which are given in Table 5.
• Example 16 is repeated, except that LWC paper is made in the absence of a dry strength agent.
• the strength values of the paper thus obtained are given in Table 5.
• Example 16 is repeated with the exception that instead of the hardening agent 1 used there, 2% native potato starch, based on dry fiber material, is now used.
• the strength values of the LWC paper thus obtained are given in Table 5.

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• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Paper (AREA)
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• Steroid Compounds (AREA)
• Medicines Containing Antibodies Or Antigens For Use As Internal Diagnostic Agents (AREA)

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• 1987
  • 1987-02-28 DE DE19873706525 patent/DE3706525A1/de not_active Withdrawn
• 1988
  • 1988-02-12 US US07/155,503 patent/US4818341A/en not_active Expired - Lifetime
  • 1988-02-16 NZ NZ223534A patent/NZ223534A/xx unknown
  • 1988-02-18 CA CA000559242A patent/CA1290508C/fr not_active Expired - Lifetime
  • 1988-02-20 DE DE8888102520T patent/DE3870941D1/de not_active Expired - Lifetime
  • 1988-02-20 EP EP88102520A patent/EP0282761B1/fr not_active Expired - Lifetime
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  • 1988-02-26 NO NO880856A patent/NO171173C/no unknown
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