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
  • 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
  • D21H21/30—Luminescent or fluorescent substances, e.g. for optical bleaching
• • 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
  • 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
  • D21H21/16—Sizing or water-repelling agents

Definitions

• the invention relates to a process for lightening paper in the size press, whitener preparations and size press liquors.
• a sizing step is usually carried out to achieve good writability and strength, which can be done on the one hand before sheet formation in the pulp (engine sizing), on the other hand after sheet formation in the size press. A combination of these two methods is possible.
• a brightening of the paper pulp or of the paper sheet is usually carried out by optical brighteners, wherein usually in the mass application, the sizing agent and the brightener of the pulp are fed separately, while incorporated in surface sizing the brightener in the size press liquor and applied together with this on the paper sheet.
• the combination of surface sizing and whitening of papers is widely used in the paper making industry. Especially in the paper segment Printing & Writing (Copy, Inkjet, Offset, etc.) this method is widely used. In addition to the more efficient lightening, a faster correction (online measurement) of the whiteness levels to be achieved is also possible. Furthermore, with the surface application, the wet end of additional anionic freights (whiteners) spared.
• triazinyl flavonate brighteners are already described as K or Na salts as optical brighteners in the size press process for lightening paper.
• K or Na salts are already described as optical brighteners in the size press process for lightening paper.
• At least 20 mol%, in particular more than 50 mol%, very particularly preferably more than 80 mol% of all cations M have the meaning of the formula II.
• brighteners containing more than 50% by weight, preferably more than 60% by weight, preferably more than 75% by weight, in particular more than 95% by weight, of a brightener Formula I exist.
• the brightener of the formula (I) may additionally be present in excess alkanolamine or alkanolammonium in the form of the free bases or corresponding salts with other, inorganic or organic, anions in the size press liquor.
• a surface application unit preferably the paper machine in which the cellulose sheet formed with an aqueous liquor containing at least one surface sizing agent, in particular starch, for example, native, derivatized or degraded, preferably oxidatively degraded starch, the so-called size press liquor brought into contact is, and in which the proportion of the fleet, which is to be absorbed by the sheet (liquor pickup) can be preferably adjusted by the roll pressure.
• the brighteners are already prepared and / or formulated in the form of their alkanolammonium salts or mixed salts of their alkanolammonium salts with their salts of inorganic bases and are finally incorporated into size press liquors in such a form which are then applied in the described preferred pH range.
• the use can, however, e.g. also be effected by reacting with an inorganic counterion, e.g.
• Lithium, sodium, potassium, calcium, magnesium, or ammonium whitening agent is contacted with the salt of an inorganic or organic acid of an alkanolamine, e.g., an alkanolamine hydrochloride or alkanolamine sulfate, and then applied in a size press liquor of suitable pH, or e.g. in that this matching only happens in the size press fleet, or z.
• an alkanolamine e.g., an alkanolamine hydrochloride or alkanolamine sulfate
• a size press liquor of suitable pH or e.g. in that this matching only happens in the size press fleet, or z.
• the alkanolamine underlying the alkanolamine is introduced in free form at any time and at any point in the manufacturing or processing and neutralized in the course with a suitable inorganic or organic acid. This of course also applies to the opposite case, namely that first the inorganic or organic acid and only then the alkanolamine is introduced
• the use according to the invention is preferably carried out by introducing into the size press liquor an aqueous solution of the brightener of suitable pH, which may possibly contain additional substances, such as carrier substances, salts or setting agents.
• Suitable carrier substances are, for example, hydrophilic polymers capable of forming hydrogen bonds.
• Preferred carrier substances are polyvinyl alcohols, carboxymethylcelluloses and polyethylene glycols having a number-average molecular weight of from 200 to 8000 g / mol, as well as any desired mixtures of these substances, these polymers optionally being able to be modified.
• Preferred polyvinyl alcohols are those with a degree of hydrolysis> 85%
• preferred carboxymethylcelluloses are those with a degree of substitution DS of> 0.5.
• Particularly preferred are polyethylene glycols having a number average molecular weight Mn of 200 to 8000 g / mol.
• carrier-free or carrier-containing formulations in smaller amounts, usually in amounts below 5 wt .-%, other auxiliaries such.
• other auxiliaries such as dispersants, thickeners, antifreeze, preservatives, complexing agents, etc., or organic by-products from the brightener synthesis, which were not completely removed in the workup, may be included.
• the brightener with only inorganic cations shows a saturation behavior with respect to the CIE from certain brightener addition amounts.
• Whiteness ie larger amounts do not lead to whiteness build-up any more and can even have a negative effect on the whiteness.
• This saturation behavior occurs when using the alkanolammonium brightener only at much higher levels, compared to the salt with only inorganic cations, on.
• the effect of saturation is also called greening.
• the greening border i. the point above which increasing brightener amounts cause virtually no increase in whiteness can e.g. are derived from the a * -b * diagram, where a * and b * are the color coordinates in the CIE-L * a * b * system.
• Aqueous whitener preparations are usually characterized by the so-called E1 / 1 value.
• E1 / 1 value the extinction of a highly diluted solution of the preparation is determined by the usual and known to the expert methods of UV / Vis spectroscopy in a 1 cm cuvette at a specific wavelength. This wavelength corresponds to the long-wavelength absorption maximum of the respective brightener molecule. For flavonate brighteners it is about 350 nm.
• the E1 / 1 value then corresponds to the imaginary extinction value extrapolated to a 1% solution of the sample to be determined.
• the invention therefore furthermore relates to a whitener preparation comprising brighteners which contain more than 50% by weight, preferably more than 60% by weight, preferably more than 75% by weight, in particular more than 95% by weight, of a brightener of the formula I exist.
• a whitener preparation comprising brighteners which contain more than 50% by weight, preferably more than 60% by weight, preferably more than 75% by weight, in particular more than 95% by weight, of a brightener of the formula I exist.
• aqueous whitener preparations which may optionally contain additional substances, such as those already mentioned, for example, above.
• the preparations according to the invention can preferably be used in the lightening process according to the invention.
• aqueous whitener preparations comprising at least one brightener of the formula (I), in particular (Ia).
• the inventive, preferably aqueous brightener preparation preferably contains at least 2.5% by weight of brightener, particularly preferably 5 to 40% by weight, in particular 10 to 30% by weight.
• the brightener preparations according to the invention may contain inorganic or organic salts, in addition free alkanolamine, in addition alkanolamine salts, carriers and other substances.
• the size press liquor may contain inorganic or organic salts, in addition free alkanolamine, in addition alkanolamine salts, carriers and other substances.
• the size press liquor contains less than 2.5% by weight of brightener, in particular from 0.01 to 2.0% by weight.
• the total brightener preferably consists, as already described for the whitener preparation, of more than 50% by weight, preferably more than 60% by weight, preferably more than 75% by weight, in particular more than 95% by weight, of one Brightener of formula I.
• the proportion of surface sizing agent, in particular starch, based on the size press liquor is preferably from 2 to 25% by weight, in particular from 5 to 15% by weight.
• the water content of the size press liquor is preferably at least 70% by weight.
• Comparative Example 3 corresponds to Example 2 of WO 00 46336.
• the procedure is up to and including the introduction of the crystals as described for Example 1b. After dissolution of the crystals, 15 g of polyethylene glycol 1500 are added, the mixture is stirred until dissolved and determines the E1 / 1 value. The mixture is then diluted at room temperature with demineralized water to a calculated E1 / 1 value of 113.
• the liquor pick-up ratio of the test paper is determined in a separate determination.
• the test of the individual brightener preparations is then carried out by diluting the respective preparation as a concentration series to a further 50.0 g of the same starch solution, diluted to 100.0 g with water, thoroughly mixed, and the resulting brightener-containing size press liquors as described above Help the Apply the laboratory size press to further test paper sheets. Finally, the papers so finished in the drying cylinder at about 100 ° C dried.
• the brightener preparations to be compared are each used in a concentration range of 0.5% by weight / 1.0% by weight / 1.5% by weight / 2.0% by weight, based on the weight of the test paper used.
• the relationship of the concentrations of brightener preparations in relation to the weight of the test paper to the corresponding concentrations in relation to the size of liquor press liquor is established using the previously separately determined liquor pick-up ratio. For example, at a liquor pick-up ratio of 0.9 in the experiment without brightener described above, the values of the above concentration series must still be divided by the divisor 0.9 to obtain their values in terms of size press liquor quantity.
• the above concentration series refers to preparations with an E1 / 1 value of 113. If preparations with a deviating E1 / 1 value are to be tested, their E1 / 1 value deviation from the guide value 113 must additionally be compensated for by: changing the concentration series in inverse proportion (for example, at an E1 / 1 value of 105, 0.538 wt% preparation is equivalent to 0.5% preparation of E1 / 1 value 113, etc.).
• Table 1 Brightener preparation from Comparative Example 1 Amount (%) CIE whiteness L * a * b * 0.50 138.08 95.95 2.96 -10.83 1.00 144.11 96.12 3.04 -12.13 1.50 145.80 96.28 2.87 -12.44 2.00 146.46 96.32 2.69 -12.57
• Table 2 Brightener preparation from Comparative Example 2a Amount (%) CIE whiteness L * a * b * 0.50 135.50 95.92 2.83 -10.26 1.00 142.76 96.12 2.98 -11.82 1.50 144.48 96.28 2.83 -12.14 2.00 145.87 96.33 2.69 -12.43
• Table 3 Brightener preparation from Comparative Example 2b Amount (%) CIE whiteness L * a * b * 0.50 135.40 95.82 2.84 -10.28 1.00 142.37 96.11 2.97 -11.73 1.50 144.24 96.22 2.87
• Table 1 Brightener preparation from Comparative Example 1 Amount (%) CIE whiteness L * a * b * 0.50 138.08 95.95 2.96 -10.83 1.00 144.11 96.12 3.04 -12.13 1.50 145.80 96.28 2.87 -12.44 2.00 146.46 96.32 2.69 -12.57
• Table 4 Brightener preparation from Example 1a Amount (%) CIE whiteness L * a * b * 0.50 138.12 96.05 2.95 -10.80 1.00 145.36 96.31 3.09 -12.33 1.50 146.98 96.34 2.96 -12.68 2.00 148.48 96.57 2.79 -12.92
• Table 5 Brightener preparation from Example 1b Amount (%) CIE whiteness L * a * b * 0.50 138.33 95.96 2.98 -10.88 1.00 145.58 96.26 3.12 -12.40 1.50 147.59 96.25 3.03
• Table 5 Brightener preparation from Example 1b Amount (%) CIE whiteness L * a * b * 0.50 138.33 95.96 2.98 -10.88 1.00 145.58 96.26 3.12 -12.40 1.50 147.59 96.25 3.03 -12.86 2.00 148.26 96.46 2.80 -12.92
• Table 6 Brightener preparation from Example 2 Amount (%) CIE whiteness L * a * b * 0.50 138.69 95.96 3.02 -10.97 1.00 145.83 96.23 3.16 -12.47 1.50 148.12 96.41 3.08 -12.92 2.00 148.74 96,39 2.86 -13.06
• Table 7 Brightener preparation from Comparative Example 3 Amount (%) CIE whiteness L * a * b * 0.50 137.64 95.95 2.89 -10.73 1.00 144.62 96.29 2.95 -12.16 1.50 146.04 96.37 2.78 -12.45 2.00 147.17 96.5 2.56 -12.65
• Table 8 Brightener preparation from Example 3 Amount (%) CIE whiteness L * a * b * 0.50 137.8 95.93 2.94 -10.78 1.00 145.6, 96.21 3.11 -12.43 1.50 147.6 96.32 2.96 -12.82 2.00 148.9 96.43 2.79 -13.08
• Table 9 Brightener preparation from Example 4 Amount (%) CIE whiteness L * a * b * 0.50 138.9 95.94 2.99 -11.02 1.00 146.3 96.29 3.11 -12.55 1.50 148.4 96,39 2.97 -12.98 2.00 149.
• a brightener preparation containing the brightener of the formula Ia (with diisopropanolamine residues on the triazine rings prepared analogously to Example 2 of WO 0046336) has a better brightening effect than the brightener preparation of Example 2 of WO 0046336, which contains a brightener mixture which additionally contains a brightener substituted with diethanolamine radicals on the triazine rings and a brightener unsymmetrically substituted with diisopropanolamine radicals and diethanolamine radicals on the triazine rings, and on the other hand that the brightening effect can be additionally increased if the free triethanolamine which is used in the procedure of Example 2 of WO 0046336 prepared whitener preparation containing the brightener of formula Ia, is neutralized by the addition of acid.

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• Agricultural Chemicals And Associated Chemicals (AREA)
• Plural Heterocyclic Compounds (AREA)
• Cosmetics (AREA)
• Detergent Compositions (AREA)

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• 2004
  • 2004-08-06 DE DE102004038578A patent/DE102004038578A1/de not_active Withdrawn
• 2005
  • 2005-07-22 US US11/187,735 patent/US7608168B2/en not_active Expired - Fee Related
  • 2005-07-23 PT PT05016038T patent/PT1624105E/pt unknown
  • 2005-07-23 EP EP05016038A patent/EP1624105B1/fr not_active Expired - Lifetime
  • 2005-07-23 AT AT05016038T patent/ATE426705T1/de active
  • 2005-07-23 ES ES05016038T patent/ES2325164T3/es not_active Expired - Lifetime
  • 2005-07-23 DE DE502005006927T patent/DE502005006927D1/de not_active Expired - Lifetime
  • 2005-08-04 JP JP2005227116A patent/JP4768349B2/ja not_active Expired - Fee Related
  • 2005-08-05 CN CN200510091692.6A patent/CN1730816B/zh not_active Expired - Fee Related
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