Fixation of optic whiteners on fibre

FIELD: textile, paper.

SUBSTANCE: procedure refers to production of wood pulp and can be implemented in pulp-and-paper industry. The procedure consists in whitening fibres of sulphate pulp with a whitening agent on base of chlorine and in washing whitened fibres of sulphate pulp. Upon washing fibres of sulphate pulp are subject to interaction with at least one optic whitener before mixing ponds. Interacting is carried out in solution at pH from 3.5 to 8.0 and temperature from 60 to 80°C during 0.5-6 hours. The invention also refers to wood pulp produced by the said procedure.

EFFECT: increased whiteness and optic brightness of paper at decreased utilisation of optic whitener.

22 cl, 11 dwg, 11 tbl, 7 ex

 

The technical FIELD

The present invention relates to a method of increasing the optical brightness of pulp, wood mass, manufactured by such methods, and to methods of using such wood pulp.

The LEVEL of TECHNOLOGY

Bleaching is a common method of increasing the whiteness of the pulp. Industry practice improve the appearance of fluff wood pulp is in its bleaching to even higher levels of optical brightness (Technical Association of the pulp and paper industry (TAPPI) or the international organization for standardization ("ISO")). However, bleaching is expensive, environmentally unfriendly process and is often the cause of bottlenecks in production. The widespread preference of consumers to a brighter and more white paper is forcing manufacturers to use more stringent strategy blanching. Although wood pulp with a high degree of blanching "whiter"than wood pulp with a lower degree of bleaching, it is all the same colour yellowish-white. Yellowish-white product undesirable. Numerous studies suggest that consumers clearly have a preference for bluish-white on yellowish-white color. The first is perceived as more white, ie, "fresh", "new" and "clean", and the latter is considered "old", "faint" and "g is yazno".

Although bleaching directly increases the optical brightness, it only indirectly increases the whiteness. As a consequence, the bleaching is not always the most effective way to enhance the whiteness of the paper. For example, even after aggressive bleaching white product can always be increased reasonable by adding pigments compared to the extent achievable using only bleaching.

The practice of coloring wood pulp for making paper is not generally used, and it is not necessarily desirable. In the first case, the intentional change of the optical properties often leads to deterioration of characteristics of the product, such as optical brightness TAPPI, which is undesirable. In the second case, there is a risk that the pigments can not withstand unpredictable conditions of production at the subsequent stages. The reason for this is that on the pre-added to the pigment may be adverse chemical and/or physical effect in subsequent operations, which will lead to unexpected or undesirable modification or even complete loss of color. In addition, some pigments may be lost or become ineffective at various subsequent operations, violating the integrity and reliability of the process. Therefore, any optical improvement is usually achieved by added what I tinting pigments, fillers and/or fluorescent dye at the stage of making paper. A method of improving whiteness, optical brightness and color of the fibers for making paper are described in U.S. patent No. 5,482,514. This method refers to the addition of photoactivation, in particular water-soluble phthalocyanines, to fibers for making paper with the aim of improving their optical properties by the method of catalytic bleaching with a photosensitizer. Received bleached fiber for making paper can successfully be introduced in paper sheets.

For fluff pulp, as well as for most products pulp and paper industry optical brightness TAPPI is actually a standard rather than a specific industry characteristics of white, such as white CIE (Commission Internationale d'éclairage). Consequently, the optical brightness plays two main roles. First, the optical brightness is a manufacturing option. Secondly, the optical brightness is a technical feature for the classification of varieties of final products. Implied, though dubious assumption so far is that the optical brightness is equivalent to white. A common practice of making paper is to add or blue tinting dye or tinting pigments, and/or a different type is in the blue-violet fluorescent dyes to improve whiteness. Semi-permanent dyes are or colored pigments finely ground, suspended in the dispersant, or synthetic direct dyes. Semi-permanent dyes have some affinity with cellulose fibres, whereas toning pigments does not have.

Fluorescent brighteners (LO) or optical brighteners (PA)used in the pulp and paper industry, are of three types: di-, Tetra - or hexachlorophene stilbene compounds, for example. These chemicals require ultraviolet (UV) radiation to excite luminescence. Although daylight has a high content of ultraviolet light, even normal office lighting creates sufficient UV radiation to initiate some excitement.

In the manufacture of paper PA is applied on the wet stage methods of paper making, using, for example, pool-mixer and/or a vane pump, if the fibers in the solution have a low consistency, less than about 3% solids. In these traditional areas adding a large part of the NGO goes to waste, because OO is not necessarily has a strong affinity with the fibers in the solution. Accordingly, the NGO must be added in large concentrations (pounds per ton of fiber or wood pulp) in order to get vysokokachestvennaya, having a high degree of optical brightness and a high degree of improvement in optical brightness.

Accordingly, there is a need in the wood mass with high brightness and optical brightness. There is also a need for a method of producing wood pulp with high white/optical brightness for any application, especially in the wood pulp for making paper and fluffed wood mass, when you use fewer of the NGO, in order to obtain such levels of whiteness and optical brightness at lower cost. The present invention is directed to the fulfillment of these needs and has a further related advantages.

BRIEF DESCRIPTION of DRAWINGS

Figure 1 - graphic optical brightness ISO against GS in leaves of hand-cast, made from wood pulp treated with PA, a complete set of data.

Figure 2 graphs the optical brightness ISO against GS in leaves of hand-cast, made from wood pulp treated with PA, the data set dose.

Figure 3 graphs the optical brightness ISO against GS in leaves of hand-cast, made from wood pulp treated with PA, the influence of the dose of PA in the presence of 10% and 20% filler.

4 is a graphic optical brightness ISO against GS in leaves of hand-casting, made of wood mA the son, processed OO, the influence of the dose of PA in the presence of 10% and 20% filler, added regression line.

5 is a Raman spectrum only PA and wood pulp with different levels of PA added by known methods.

6 is a Raman spectrum of a wood pulp with different levels OO added according to one aspect of the present invention.

7 is a Raman spectrum of a wood pulp with different levels of PA added by known methods and are added according to one aspect of the present invention.

Fig - graph relations peaks (1604/900 cm-1in Raman spectra of wood pulp with different levels of PA added by known methods and are added according to one aspect of the present invention (hardwood and softwood pulp), according to table 10.

Fig.9 - UV/VIEWS absorption capacity at 350 nm of an aqueous extract against the actual number of PA on the fibers, in pounds per ton.

Figure 10 - peak height of the PA against the amount of added PA (pounds per ton) by a known method of adding and according to one aspect of the present invention (hardwood and softwood pulp).

11 - the height of the peak of the PA against the amount of added PA (pounds per ton), the traditional method of adding and according to one of the aspect of the present invention (hardwood and softwood pulp).

DETAILED description of the INVENTION

The author of the present invention unexpectedly discovered a way to effectively increase the optical brightness and whiteness of pulp and paper using fewer OO and thus provides a much more efficient formation of complex fiber-OO with increased interaction between the fiber and the PA than in the known methods of formation of complex fiber-OO. This complex fiber-OO, obtained by the method according to the present invention, has a greater increase in optical brightness and whiteness than one fiber in comparison with the known methods, described below.

The present invention relates in part to a method of producing wood pulp. Wood pulp can be crushed or wood pulp for paper production. This method can be used in addition to any well-known methods for the production of fluff pulp or wood pulp for paper production. Wood pulp can be used for any known application, including any known methods of production of paper and/or cardboard bases. Such known methods of manufacturing wood pulp and paper you can find, for example, in "Handbook For Pulp & Paper Technologies" {Handbook on pulp and paper technology, 2nd Edition, G.A. Smook, Angus Wilde Publications (1992) and listed what's in it for reference materials which are incorporated in full herein by reference.

A typical method of manufacture of wood pulp/paper may contain, without limitation, the following stages:

A. Stage of cooking wood chips to separate cellulose fibers from lignin.

C. the washing Step from the cooking liquor, which is washed fibrous mass after boiling.

C. Stages of bleaching/extraction, in which the fibrous mass is removed and bleached with the use of various chemical substances, such as oxygen during oxygen delignification, chlorine dioxide, elemental chlorine, peroxide, ozone, etc. followed by one or more rinsing steps.

D. the storage at high density, which bleached/washed fibrous mass is kept at a relatively high density, for example more than about 7%, preferably from about 7.5% to 15%, and more preferably from about 10% to 12%.

That is, the Stage of storage at low density, where bleached/washed fibrous mass is kept at a relatively low density, for example, equal to or less than about 7%, preferably from about 3% to 7%, and more preferably from about 10% to 12%.

D. Stage of gentrification, in which the fibrous mass and elevated in consistency from about 4% to 5%./p>

E. Stages of mixers, in which the wood pulp having a consistency of preferably from about 3% to 4%, mixed with chemicals wet stage, used in the manufacture of paper, such as fillers, means of restraint, dyes and optical brighteners, etc. Such known methods may include re carrying out any one or more of the above stages. In addition, the present invention can be combined with known methods of adding OO to the fibers, for example, in the usual spots add to the wet stage and the points add coatings in the manufacture of paper and/or cardboard.

The present invention relates in part to a method of adding OO to the fibers at any point after the last stage bleaching/extraction prior stages of mixers.

Source of fibers can be any fibrous plant. The paper base may contain recycled fiber, bleached fibers and/or natural fibers. Examples of such fibrous plants are trees, including deciduous trees and coniferous trees, a mixture of their fibres. In some embodiments, the implementation of at least part of the cellulose fibers can be obtained from non-woody herbaceous plants, including, without limitation, kenaf, hemp, jute, flax, sisal and abaku, although legal is their limitations and other considerations may make the use of cannabis and other sources of fibers impractical or impossible. In the method of the present invention can be used bleached or unbleached cellulose fibers. Also suitable for use of recycled cellulose fibers.

Wood pulp of the present invention may contain from 1 to 99 wt.%, preferably from 5 to 95 wt.%, cellulose fibers hardwood and/or softwood from the total amount of cellulose fibers. This range includes 1, 2, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95 and 100 wt.%, including any and all ranges and subranges therein, from the total amount of cellulose fibers.

If the wood pulp may contain fibers of hardwood and softwood, it is preferable that the ratio of fibers deciduous/coniferous species ranged from 0.001 to 1000. This range may include 0,001, 0,002, 0,005, 0,01, 0,02, 0,05, 0,1, 0,2, 0,5, 1, 2, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 200, 300, 400, 500, 600, 700, 800, 900 and 1000, including any and all ranges and subranges therein and the reciprocal of such a relationship.

Optical brighteners are fluorescent compounds of the type dyes, which absorb short-wave ultraviolet radiation, not visible to the human eye, and emit longer-wavelength blue light, with the result that the human eye perceives a higher degree of whiteness, thus increasing the degree of whiteness. Optical brighteners used in the paper is the second industry, usually are 1,3,5-triethynylbenzene 4,4'-diaminostilbene-2,2'-disulfonic acid, which may have additional sulfopropyl, for example, only 2, 4 or 6. The review of these bleaches can be found, for example, in Ullmann''s Encyclopedia of Industrial Chemistry (Ullmann's encyclopedia of industrial chemistry). Sixth Edition, 2000 Electronic Release, optical brighteners - Chemicals technical products. However, also suitable and new types of bleaches, for example derivatives of 4,4'-distributional like the one described in the above Ullmann''s Encyclopedia of Industrial Chemistry, which is incorporated in full herein by reference. Although in the present invention, the preferred methods and systems of the fiber-OO using the aforementioned NGO, the present invention is in no way limited to such illustrative implementation options, and it can be used any 00.

The present invention relates in part to the complex fiber-OO, in which the affinity of PA added to the fiber according to the present invention, more than in cases where the NGO is added to the fiber by known methods. If PA is added to the fiber according to the method of the present invention, it is necessary to add a PO in the amount of < 30%to 60%, than in the known methods and points added. The reduction may be 30, 31, 32, 33, 34, 35, 40. 45, 50, 55, 56, 57, 58, 59 and 60% of p is compared with the amount required in the known methods and points are added, including any and all ranges and subranges within these limits.

The increased affinity of PA with the fiber can be measured by extraction using any solvent, preferably water, at any temperature. Because PA has a high affinity for the fibre in General, proposed in the present invention woody masses and paper basics made from them, for the extraction of PA from a complex of GS-wood pulp of the present invention will require more time at a certain period of time and temperature for a particular solvent.

In addition, the present invention preferably relates to a method for increasing the penetration of PA in the cell walls of the fibers. Preferably, a greater number of PA penetrate cell walls of fibers treated in accordance with the present invention than that of the fibers treated by known methods. More preferably, the number of NGOs present in the cell walls of the fibers, will increase by at least 1% compared with the number of NGOs present in the cell walls of fibers treated by known methods. However, more preferably, the number of NGOs present in the cell walls of fibers increased by at least 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 0, 100, 200, 300, 500, and 1000% in comparison with the number of NGOs present in the cell walls of fibers treated by known methods, including any and all ranges and subranges within these limits.

The number of NGOs present in the cell walls of the fibers can be measured, for example, microscopy, more specifically fluorescent microscopy.

Although fiber can be added to any number of the PA, because it is added at any point after the last stage bleaching/extraction to the stage of processing in the mixer, it is preferable to add from 1 to 60 pounds OO per ton of fiber, more preferably not more than 30 pounds per ton, and most preferably not more than 15 pounds of PA per ton of fiber. This range includes 60, 55, 50, 45, 40, 30, 35, 30, 25, 20, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2 and 1 pound of PA per ton of fiber, including any and all ranges and subranges within these limits.

In addition, the fiber may be in solution or may be added to the solution simultaneously with the NGO. Preferably, the fiber is in the solution to contact the NGO with him. In one embodiment of the present invention, the fiber may have any consistency. However, it is preferable that the consistency of the solids was equal to or greater than 4%, more preferably not less than about 5%, most preferably not less than approximately 10%. In addition, preferably, to fiber had the consistency of solids not greater than about 35%, more preferably not more than 20%, most preferably no more than about 15%. These ranges include the consistency of solids 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 and 20% while adding OO to the fiber, including any and all ranges and subranges within these limits.

While adding OO to fiber pH value can be anything. Preferably, the pH value can be from 2.5 to 8.0, more preferably from 3.5 to 5.5. This range includes values 2,5, 3,0, 3,5, 4,0, 4,5, 5,0, 5,5, 6,0, 6,5, 7,0, 7,5 and 8.0, including any and all ranges and subranges within these limits.

While adding OO to the fiber temperature may be any. However, preferably the use of tools such as heat, to create a temperature from 35 to 95°C., preferably from 50 to 90°C., more preferably from 60 to 80°C. This range includes 35, 40, 45, 50, 55, 60, 61, 62, 63, 64, 65. 66. 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 85, 90 and 95°C., including all ranges and subranges within these limits.

The contact time of the PA fiber, it can be anything. Preferably the NGO and the fiber can be contacted from 30 minutes to 12 hours, more preferably from 45 minutes to 8 hours, most preferably from 1 hour to 6 hours. This range includes 0,5, 0,75, 1, 1,25, 1,5, 1,75, 2, 2,25, 2,5, 2,75, 3, 3,25, 3,5, 3,75, 4, 4,25, 4,5, 4,75, 5, 5,25, 5,5, 5,75, 6, 6,5, , 7,5, 8, 8,5, 9, 9,5, 10, 11 and 12 hours, including any and all ranges and subranges within these limits.

During contact of the NGO with the fiber can be added or be present means of restraint. Examples of such means of restraint are alum and/or cationic means of restraint. Examples of means of restraint can be found in the provisional patent application U.S. 60/660703 filed March 11, 2005, and in U.S. patent No. 6,379,497, which are fully incorporated herein by reference. However, you may use any means of retention. usually used with OO. Although the means of restraint may be present in any amount, or not present at all, it is preferable that the number of present means of restraint was less than that required in the known methods and points added when PA contact with the fibers. Most preferably, the means of restraint are not used. If the means of restraint are used, it is preferable that the amount of the deduction was reduced by at least 1% compared with the known methods and points added when PA contact with the fibers. Preferably, the reduction amount of the deduction is at least 2, 3, 4, 5, 10, 15, 20, 25, 30, 35, 40, 50, 60, 75, 100, 200, 300, 500 and 1000% in comparison with the known methods and points add contact PA with fiber is AMI, including any and all ranges and subranges within these limits.

Although fiber can be refined at any time, preferably fiber ennoble after PA contact with the fiber. Therefore, the complex fiber-OO of the present invention improved. Respectively, can be conducted in any known refining, including, without limitation, chemical refining, mechanical finishing, thermochemical refining, thermomechanical refining, chemical-thermomechanical beautification, etc. So the resulting wood pulp may contain thermomechanical pulp, chemi-thermomechanical pulp, mechanical pulp, bleached chemi-thermomechanical pulp, etc.

Wood pulp of the present invention and its preparation can be included in any known method of making paper. Wood pulp and/or paper base may also contain other known additives, such as, for example, starch, mineral and polymer fillers, bonding agents, the means of keeping and strengthening polymers. Fillers that can be used include organic and inorganic pigments, such as, for example, minerals such as calcium carbonate, kaolin and talc, as well as advanced and expandable microspheres. Other known additives VK is ucaut without limitation, wet-strength resins, internal adhesives, shopruche resin, alum, fillers, pigments and dyes. Particularly preferred dyes are blue, that can improve the whiteness CIE wood pulp and/or paper base. Preferably, the wood pulp and paper Foundation of the present invention, obtained according to the present invention is able to achieve whiteness CIE, which is much higher than in the known tree masses and foundations, obtained by known methods, even when the levels of CIE whiteness, which usually lead to lower levels of optical brightness ISO.

Wood pulp and/or paper base of the present invention can have any whiteness CIE, but preferably has a CIE whiteness more than 70, more preferably greater than 100, most preferably more than 125 or even 150. The value of the CIE whiteness can be in the range from 125 to 200, preferably from 130 to 200, most preferably from 150 to 200. The range of CIE whiteness can be equal to or greater than 70, 80, 90, 100, 110, 120, 125, 130, 135, 140, 145, 150, 155, 160, 165, 170, 175, 180, 185, 190, 195 and 200, including any and all ranges and subranges within these limits. Examples of measurement of CIE whiteness and a white fibers and the paper made from them, can be found, for example, in U.S. patent No. 6,893,473, which fully incorporated herein by reference.

Preferably, wood pulp and/or the paper base of the present invention has a CIE whiteness, which is higher than in the known wood mass and/or paper bases obtained by known methods. Preferably, the increase in Whiteness CIE is at least 2, 3, 4, 5, 10, 15, 20, 25, 30, 35, 40, 50, 60, 75, 100, 200, 300, 500, and 1000% in comparison with the known tree masses, paper basics, obtained by known methods and known points add contact PA with fiber, including any and all ranges and subranges within these limits.

Wood pulp and paper Foundation of the present invention can be any optical brightness ISO, but preferably more than 80, more preferably greater than 90, most preferably more than 95. Optical brightness ISO may preferably be from 80 to 100, more preferably from 90 to 100, most preferably from 95 to 100. This range includes the values of the optical brightness ISO, equal to or greater than 80, 85, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99 and 100, including any and all ranges and subranges within these limits. Examples of optical measurement ISO brightness and a brightness in the fibrous mass for the manufacture of paper and paper made from it, can be found, for example, in U.S. patent No. 6,893,473, which is incorporated in full herein by reference.

Preferably, wood pulp and/or paper base of the present invention has an optical brightness ISO, which is higher than in the known wood mass and/or paper basics obtained by known methods.

The preferred increase in brightness ISO is at least 2, 3, 4, 5, 10, 15, 20, 25, 30, 35, 40, 50, 60, 75, 100, 200, 300, 500 and 1000% in comparison with the known brightness of tree masses, paper bases obtained by known methods and the points add contact PA with fiber, including any and all ranges and subranges within these limits.

The present invention is described in more detail using the following example of a variant of implementation, which is not intended to limit the scope of the present invention in any way.

EXAMPLES

COMPARATIVE EXAMPLE 1

Performed laboratory experiments on simulation of operations of manufacturing commercial paper, in which the T-100, tetrachlorophenyl PA from the company Clariant, was added to three samples of bleached Kraft pulp of hardwood. Mixing wood pulp with all chemicals used in laboratory mixer "Warring" with low speed. Before adding an optical Brightener (OO) to the sample pulp kiln drying weight of 5 g was added deionized water to reduce its consistency to 1%. Soon after adding the NGO in a mixture of wood pulp was added 5 ml of a 5%solution of alum to complete the consolidation of all CV on the fiber. After mixing in mixer for 1 min CME is ü wood pulp was obezvozhivani to obtain a sample for measuring the brightness according to Tappi standard procedures for testing the optical brightness. In these experiments we used three samples of wood pulp and three doses of T-100. The results of measuring the brightness on separate samples of the pulp before and after fixation of the PA are as follows.

90,4
Table 1
Sample 1Sample 2Sample 3
Brightness (GE)Increase brightnessBrightness (GE)Increase brightnessBrightness (GE)Increase brightness
080,5084,4086,60
483,12,687,73,390,03.5
884,23,789,75,1the 3.8
1684,94,389,45,090,74,1

COMPARATIVE EXAMPLE 2

Performed laboratory experiments on simulation of operations of manufacturing commercial paper, in which the T-100, tetrachlorophenyl PA from the company Clariant, was added to one sample of bleached sulphate pulp southern hardwoods. Mixing wood pulp with all the chemicals used laboratory mixer "Warring" with low speed. Before adding an optical Brightener (OO) to the sample pulp kiln drying weight of 5 g was added deionized water to reduce its consistency to 1%. In experiments I-series soon after adding the NGO in a mixture of wood pulp was added 5 ml of a 5%solution of alum to complete the consolidation of all CV on the fiber. In the experiments of series II alum is not used. In both cases, after mixing in mixer for 1 min the mixture of wood pulp was obezvozhivani to obtain a sample for measuring the brightness according to Tappi standard procedures for testing the optical brightness. In these experiments we used three samples of wood pulp is three doses of T-100. The results of measuring the brightness on separate samples of the pulp before and after fixation of the PA are as follows.

Table 2
Series I - Without alumSeries II - alum
Brightness (GE)Increase brightnessBrightness (GE)Increase brightness
084,0084,00
387,43,4
689,05,0
1089,7the 5.7
2085,81,8of 89.15,1
4086,42,386,22,1
6086,72,782,21,8

Table 3
Series I - Without alumSeries II - alum
Brightness (GE)Increase brightnessBrightness(GE)Increase brightness
084,0084,08
387,43,4
b89,05,0
1089,7the 5.7
2085,80,8of 89.15,1
4086,42,386,22,1
6086,72,782,21,8

Table 4
Water bath at 60°CWater bath at 75°C
The number of T-100Reaction time (h)Brightness(GE)Increase brightnessBrightness(CE)Increase brightness
0088,9088,90
2193,04,191,82,9
4193,64,6for 93.44,5
8194,96,094,75,8
0088,9088,90
2592,2-3,392,03,1
4593,64,6of 92.7the 3.8
8594,05,193,9a 4.9

EXAMPLE 2

Samples of fully bleached Kraft pulp of hardwood and softwood were taken at the output of the installation of commercial bleaching pulp and paper mill in the southern United States and was used for the experiments on fixate the PA high concentrations. Conditions of the experiments, including the type of NGO and consistency wood pulp were similar to those described in example 1. The sample obtained coniferous wood pulp had a pH of 5.2, deciduous wood pulp and 6.7. Each experiment lasted for two hours, the bath temperature of 65°C. for some experiments with deciduous woody mass of diluted hydrochloric acid was added to the obtained wood mass to reduce the pH to 4.9 during the reaction with the NGO. The following results were obtained.

2,5
Table 5
Col. T-100 (pounds per ton)Hwain. other mass of 5.2The worksheet. other mass of 6.7The worksheet. other mass of 4.9
Brightness (GE)Increase brightnessBrightness (GE)Increase brightnessBrightness (GE)Increase brightness
085,5085,6085,60
89,4387,51,990,14,5
5,089,7488,52,9for 91.3the 5.7
1091,2589,33,7
1591,5690,24,692,46,8

EXAMPLE 3

Samples of fully bleached pulp of deciduous and coniferous species were taken at the output of the installation of commercial bleaching pulp and paper mill in the southern United States and were used for experiments on fixing the toe. The pH value of the filtrate of both samples of wood pulp was 3.0. In this example, used desulfosporosinus PA "Leucophor ANO" the company Clariant. Experiments fixation was performed with different number of added PA, consistency 10%, for two hours in the bath is a temperature of 65°C. In the fixation of PA observed the following changes in the brightness of the pulp.

30
Table 6
Col. Leucophor(pounds per ton)Deciduous wood pulpConiferous wood pulp
Brightness (GE)Increase brightnessBrightness (GE)Increase brightness
089,3088,40
593,64,392,84,3
1094,3a 4.9to 92.13,7
15of 92.73,490,42,0
2091,92,689,61,1
89,3086,0a-2.5

EXAMPLE 4

This example used the samples of wood mass and CBOs in example 3. However, before mixing OO diluted solution of NaOH was used to increase the pH of samples from 3.0 to 5.7 for deciduous wood pulp and up to 7.0 for coniferous wood pulp. All other conditions were the same as those of example 4. The result of pH adjustment and fixation of the NGO observed the following changes in the brightness of the pulp.

Table 7
Col. Leucophor (pounds per ton)Deciduous wood pulpConiferous wood pulp
Brightness (GE)Increase brightnessBrightness (GE)Increase brightness
089,0087,90
4for 93.44,492,54,
894,95,893,85,9
1295,16,394,06,1
2095,56,594,86,8
3089,36,695,17,2

EXAMPLE 5

Conducted experiments on fixing T-100 on samples of commercial fully bleached softwood and hardwood sulphate pulp with pulp and paper mills in the Northern United States. Coniferous wood pulp had a degree of grinding 690 csf, optical brightness 90 GE and pH 4.0. Sample deciduous wood pulp had a degree of grinding 570 csf, optical brightness of 89.2 and pH 4.0. Different doses of the T-100 was mixed with a fibrous mass with the consistency of 10% and stored the samples in a separate sealed plastic bags. The bags were placed in a water bath with a temperature of 70°C for 2 hours. Changes in the brightness of individual samples of wood pulp in the fixation of PA were as follows.

Table 8
Number.Coniferous wood pulpDeciduous wood pulp
T-100 (pounds per ton)Brightness (GE)Increase brightnessBrightness (GE)Increase brightness
090,0089,20
294,44,492,02,8
4for 95.25,2of 92.73,5
b95,85,893,34,1
896,36,393,84,6
1096,66,694,2 5,0
12to 97.17,194,35,1

EXAMPLE 6

Raw samples of coniferous and deciduous wood pulp from example 5, together with samples, fixed T-100 in the amount of 12 pounds per ton, was exposed to high mechanical stress of the slice in a laboratory refiner "PFI". The degree of refining wood pulp controlled so that the degree of grinding of coniferous wood pulp decreased from 690 CSF before finishing up to 450 CSF after finishing. The degree of grinding deciduous wood pulp decreased from 570 CSF to 330 CSF. In the refining of raw samples and samples containing OO, changes in brightness were as follows.

The loss in brightness in the refining wood pulp is well known in the manufacture of paper. In terms of gentrification in example 6, it was 1.6 points for untreated coniferous wood pulp and 0.8 for raw deciduous wood pulp. Loss of brightness were very similar for the case when wood pulp was mixed with PA, which implies that the strength of this relationship between PA and fiber, which is not influenced by the mechanical force of the slice in the refiner. H the hundred enhancing brightness in the fixation of PA remained essentially unchanged; finishing wood pulp it is not affected.

EXAMPLE 7

Study sheets manual casting

Summary

Study sheets manual casting confirmed that the addition of optical Brightener (PA) Leucophor ANO company Clariant on the method of processing at high consistency gives increased brightness compared with the addition of PA at low consistency.

For a fixed dose of a new insertion point resulted in increased brightness of approximately 1.9 unit optical brightness ISO.

Based on the data of this study to achieve the same degree of optical brightness ISO when using a new way to add a dose of PA decreases by 3.5 pounds per ton.

These estimates are based on data for dose levels of PA from 3.3 to 10 pounds per ton. The experiment proved that two factors, namely the dose of PA (nominally 3.3 and 10 pounds per ton) and how to add PA (new method against adding to wood mass low consistency), were statistically significant in determining the brightness.

Experimental part

1. Wood pulp

For this study used highly plasticised deciduous and coniferous wood pulp from the washing basin of the last stage of bleaching.

2. Commit PA

Hardwood pulp and softwood pulp separately with two quantities OO 3.3 and 10 f is now per tonne. As PA used Leucophor ANO (the company Clariant), which is desulfonatronum PA. As conditions were taken: consistency 10%, stirring for 2 h at 70°C.

3. Improvement

Before finishing wood pulp were mixed in the ratio of 70:30 (deciduous-coniferous). The elevation was performed in a laboratory disc refiner LR1. Used two values of energy 35 kW/t and 45 kW/tshepang grinding the resulting wood mass was ~580 and ~320 csf, respectively.

4. Manufacturing sheets

The sheets were made on a dynamic casting machine in the following way. Wood pulp was diluted to a consistency of 1% under vigorous stirring. First added polycarbonate calcium (PAC) "Albacar LO RCC" SMI and was stirred for 1 min. Then defined and accurately measured amount of PA was added and was stirred for 15 minutes and Then was molded sheet. After molding the sheets were pressed to the solids content of 45% and dried at a temperature of 230°F on the drying cylinder. Had taken special precautions to ensure that the sheets "fixed" PA had a number of NGO similar to the standard sheets with added toe. In addition to the samples pre-treated CV and samples, prepared as above, where the PAC was added to the PA, were made a few to ntalnyh samples to which is added the PAC and PA was changed (first added OO).

5. Test

The sheets were tested on different optical properties using a spectrophotometer "DataColor Eirepho".

6. The experiment plan

The plan of this experiment took into account four main factors:

I) the consistency of the mass, to which was added OO (10% vs. 1%);

II) the elevation (35 kW/ton, compared to 45 kW/ton);

III) filler content (10% versus 20%);

IV) dose of PA (3,3 against 10 pounds per ton).

Results and conclusions

Comparison of the brightness of the sheets manual casting obtained by the new and known methods

Adding an optical Brightener (00) Leucophor ANO company Clariant under the new method of processing at high consistency gave a higher brightness than adding in low texture sheets for hand casting. These results are shown in Fig.1-4, which summarizes all research data on the brightness in the form of a graph against the dose of PA. Given a few different classes of samples, separated by way of fixing (at high and low consistency) and the content of the filler (10 and 20 pounds per ton).

The study of wood pulp OO method of Raman spectroscopy

Raman spectroscopy was used to study wood pulp with the NGO added according to known and new methods for the am. Figure 5 shows the comparison of the spectrum of PA (Leucophur ANO) with the spectra of wood pulp with added OO and without PA. The most intense peak in the spectrum of PA approximately 1600 cm-1see in the spectrum of wood pulp with added toe. Figure 6 shows spectra of wood pulp (extended range from 300 to 1700 cm-1) with different content of added PA. The intensity of the peak at 1600 cm-1increased with increasing content of PA. When comparing the spectra of wood pulp with the NGO added according to known and new methods was not observed changes in the form of peaks and more peaks (see Fig.7). To determine the relative number of NGO attached to the fibers was calculated by the ratio of the intensity of the peak at 1600 cm-1to the intensity of the peak at 900 cm-1(peak cellulose) for woody masses with different content added PA. The results are presented in the table and Fig.

TABLE 10
MethodThe number of added OO, pounds per tonThe ratio of the height of peaks
Known00,026
100,469
150,637
200,711
New (other deciduous weight)00,034
3,30,238
100,648
New (other coniferous weight)00,071
3,30,371
100,685

The results of measurements of Raman scattering show that the number of OO in wood mass obtained according to the method of the present invention, compared with the quantity of OO in wood mass, obtained in a known manner when the number of PA 15-20 pounds per ton.

A study of NGO in the wood mass spectroscopy with induced plasma (SIP)

Samples of coniferous and deciduous wood pulp with added PA according to known and new ways of gidrolizom is whether on a hot plate using hydrogen peroxide and nitric acid. Sample PA, used in a particular way, dried and hydrolyzed in the same conditions. Hydrolyzed samples were analyzed for sulfur content by the method of m & as. The results are presented in table 11. Raw wood pulp was also analyzed in the same conditions and measured sulfur content read from the content in the treated wood mass in order to set the number of NGOs present in wood mass, to obtain values of dry mass of the toe.

Table 11
MethodAdded OO, pounds per tonSulfur in SIP, parts per millionSera from PA on the fiber, parts per millionSulfur on the fiber, parts per million (results sulphur)
Known0150
1019040697
20250100 1744
New (other deciduous weight)0140
102501101918
New (other coniferous weight)0140
10150841465
OO (kiln drying)57600; 57100

The concentration of sulfur in wood mass show that the number of NGOs present in wood mass processed by the method according to the present invention 10 pounds OO per ton, compared with the quantity of OO in wood mass, obtained in a known manner at 20 pounds per ton.

Research extraction

Approximately 1 g of drivernames cut into small pieces and soaked in approximately 150 ml of water for 6 hours at 60°C.

Water extracts were filtered through a 0.45 µm filter, restored to a volume of approximately 2 ml in the evaporation system with nitrogen "LABCONCO Rapidvap, using air as the purge gas. The evaporator has worked with the speed of a whirlwind 24% at 30°C. After evaporation to approximately 2 ml of sample was transferred into a volumetric flask 5 ml

Part of this amount 5 ml of the water extract was analyzed by liquid chromatography high resolution (IHVR).

Part of this amount 5 ml of aqueous extract was diluted in ratio 1:10 for UV/TYPE of analysis.

Characteristics of equipment for GHUR

Description of device: the separation block "Waters Alliance 2695" matrix photodiode detector model "Waters 996".

Mobile phase: 50% methanol, 50% buffer solution "PIC-A" at 0.7 ml/min PIC-A sold by the company Waters Corporation and serves as a buffer solution for ion-exchange chromatography with reversed phase, containing 0.005 M tetrabutylammonium phosphate with bringing to pH 7.5.

Column: Phenomenex Luna 5 μm C-8 (2) 250 mm × 4.6 mm, work at 35°C.

Detector: photodiode matrix detector, Waters 400" for the range 200-800 nm. For analysis was selected peak at 254 nm.

The process time of 60 minutes

Amount of I - 10 ál.

Characteristics of equipment for UV/

Description of instrument: Shimadzu model UV-160 operating in the photometric mode.

Wavelength, IP is alzouma for analysis, 350 nm.

The results are shown in Figures 9-11.

In light of the above description numerous possible modifications and changes. It is therefore understood that within the scope of the attached formula of the invention may be implemented differently than described in this document.

Specified in this document ranges are used as the short name to describe any and every value that is included in it, including all sub-ranges.

All links and references referred to therein, are incorporated herein with respect to specific parts relating to the subject matter of the present invention and all variants of its implementation.

1. The method of manufacture of wood pulp, including the bleaching of many fibers sulphate pulp bleaching agent is chlorine-based, washing many bleached fibre sulphate pulp after bleaching and after washing the interaction of fibre sulphate pulp in solution at a pH of from 3.5 to 8.0 and at a temperature of from 60 to 80°C for from 0.5 to 6 h with at least one optical Brightener before the stage of basin-mixer.

2. The method according to claim 1, where after washing this interaction is carried out in solution at a pH of from 3.5 to 5.5.

3. The method according to claim 1, where the consistency of the fibers in the solution is more than 4%.

4. The method according to claim 1, where cons is Stantsiya fibers in the solution is from 7 to 15%.

5. The method according to claim 1, where the optical Brightener in an amount of from 1 to 15 pounds per ton interacts with the fibers.

6. The method according to claim 1, where the interaction occurs at the point in the process of manufacturing wood pulp or paper manufacturing to the stage of refinement.

7. The method according to claim 1, where this interaction occurs without restraint Supplement.

8. The method according to claim 1 which further includes the additional interaction of bleach with the fibers when the napylitel.

9. The method according to claim 1 which further includes the additional interaction of bleach with the fibers when working size press.

10. The method according to claim 1, where the consistency of the fibers in the solution is from 10%to 12%.

11. The method according to claim 1, where many bleached fibre sulphate pulp in the solution has an ISO brightness of less than 90 to the interaction of multiple fibre sulphate pulp in a solution of at least one bleach and ISO brightness, more than or equal to 90 after the interaction of multiple fibre sulphate pulp in a solution of at least one bleach.

12. The method according to claim 1, where many bleached fibre sulphate pulp in the solution has an ISO brightness of less than 90 to the interaction of multiple fibre sulphate pulp in a solution of at least one bleach and ISO Yar is awn, more than or equal to 92 after the interaction of multiple fibre sulphate pulp in a solution of at least one bleach.

13. The method according to claim 1, where the fibre sulphate pulp obtained from deciduous trees.

14. The method according to claim 1, where the fibre sulphate pulp obtained from coniferous trees.

15. Wood pulp obtained by a method according to claim 1.

16. Wood pulp indicated in paragraph 15, where the wood mass is fluffed wood pulp.

17. Wood pulp indicated in paragraph 15, where the wood mass is wood pulp for paper production.

18. Wood pulp indicated in paragraph 15, which has an optical brightness ISO not less than 90.

19. Wood pulp indicated in paragraph 15, which has an optical brightness ISO not less than 95.

20. Wood pulp indicated in paragraph 15, which has an optical brightness ISO not less than 98.

21. Wood pulp indicated in paragraph 15, which has a CIE whiteness of not less than 130.

22. Wood pulp indicated in paragraph 15, which has a CIE whiteness of not less than 130 and the optical brightness ISO not less than 90.



 

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2 cl, 1 tbl

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1 tbl, 17 ex

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