JPH0635113A - Diazo photosensitive copying paper - Google Patents

Abstract

PURPOSE:To obtain the diazo photosensitive copying paper free of emission of fluorescent light even if used paper pulp is contained by incorporating the used paper pulp obtained by mixing a dichloroisocyanurate fluorescence quencher with the used paper pulp in the raw paper material. CONSTITUTION:The diazo photosensitive copying paper has on a paper base a diazo color-developing layer, and the paper base contains the used paper pulp obtained by mixing the dichloro-isocyanurate fluorescence quencher with the used paper pulp in a pulp concentration of >=25% and stirring the mixture. The sources of the used paper are as follows; superior white paper, ruled white paper, cream white paper, card board, superwhite paper, middle white paper, simili paper, white paper, Kent paper, white art paper tokujougiri paper, betoujougiri paper, news paper, magazine, etc. Effective fluorescence quenching can be executed in a small amount of quencher to be added and AOX (a content of an adsorbable organic halogen) is restrained from being produced by allowing the quencher composed essentially of the dichlorocyanurate to react with the pulp as high in the content as >=25%.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a diazo photosensitive paper mixed with waste paper pulp. More specifically, it relates to a diazo photosensitive paper obtained by blending a waste paper pulp with fluorescence eliminated in the base paper.

[0002]

2. Description of the Related Art Photosensitive papers of diazo are photo-decomposed of a diazonium salt and the diazonium salt is a coupling component (coupler).
Reacts with azo dye (coupling reaction) 2
One-component system in which a photosensitive solution containing a diazonium salt and a stabilizer such as an acid is applied to the surface of the base paper according to the developing method, and a photosensitizer containing a stabilizer such as a diazonium salt, a coupler and an acid. It is classified into a two-component system in which a layer is applied and a three-component system in which a diazonium salt, a coupler, and a developer that generates an alkali by heat are applied.

In the two-component and three-component photosensitive papers, the above-mentioned chemicals are usually used together with auxiliary agents such as stabilizers, antioxidants, development accelerators, color tone improvers, dissolution aids and concentration enhancers. The agents are mixed and applied.

In recent years, a large amount of information paper called OA paper has been discarded from office buildings and factories, and the treatment of these rapidly increasing combustible dusts has become a serious social problem. For this reason, there is a strong demand for establishment of a method for reusing recycled pulp from the viewpoints of effective use of resources and international environmental problems. By the way, the recovery rate of used paper in Japan is about 50.
%, Which is higher than that of other developed countries, and studies are underway to further increase the recovery rate to 55%. Among them, 90% of recovered newspaper is recovered, and it is widely established as recovered paper pulp.

On the other hand, when recycled pulp of recycled paper such as OA paper is used as a raw material, there is a possibility that various problems may occur in terms of quality. Therefore, the recycled pulp is hardly reused. For this reason, the reuse of old used newspaper pulp as well as recycled pulp obtained from information paper is not limited to the problems of each local government, but occurs due to global forest protection or waste paper incineration. It has become an urgent task as a part of the solution to the international environmental problems such as the global warming phenomenon caused by carbon dioxide.

[0006] The base paper for diazo photosensitive paper is no exception, and it is desired to incorporate the waste paper pulp into the base paper for the purpose of recycling the waste paper pulp. However, when a base paper containing waste paper pulp is used as a base paper for diazo photosensitive paper, there arises a problem that a fluorescent color is generated also in the photosensitive paper base paper due to the fluorescence contained in the waste paper pulp. That is, the fluorescent whitening agent is widely applied because it is necessary to adjust the color tone in the paper manufacturing process.

The whiteness of the paper is emphasized by the addition of a fluorescent agent. Therefore, if the compounding amount of the fluorescent agent is not kept constant, there will be a difference in apparent whiteness. Usually, a fluorescent whitening agent is not used in diazo photosensitive paper, and when a used waste paper pulp having a fluorescent property is mixed therein, a difference in apparent whiteness is caused due to the fluorescent intensity of the used paper, and the commercial value is significantly impaired.

As described above, used paper contains a large amount of paper containing a fluorescent whitening agent, which makes selection difficult. On the other hand, there are some paper products that dislike fluorescent coloring, so when using waste paper pulp mixed in such paper,
The original fibrous material must be restored by removing or decomposing the fluorescent color. However, the fluorescent color cannot be erased by an ordinary waste paper treatment method such as hydrogen peroxide bleaching which is conventionally used for recycling waste paper.

For this reason, Japanese Patent Application Laid-Open No. 62-97993 discloses a method of erasing fluorescence adhering to pulp with sodium hypochlorite. However, the desired quenching of fluorescence is insufficient according to the present invention. When the desired fluorescence is erased by this method, the whiteness of the pulp itself is lowered (hypo fading). In addition, when attempting to perform sufficient fluorescence quenching, severe oxidation occurs and
Although the fiber itself is damaged and the fluorescence can be erased, it becomes a poor quality pulp fiber.

Japanese Patent Publication No. 48-1693 discloses a technique for quenching a conventional fluorescent whitening agent by using sodium dichloroisocyanurate. However, the dichloro isocyanuric acid sodium salt used in the present invention is a chlorine-based compound, and it is sufficient to try to quench the fluorescence by using the conventional method for treating waste paper used in the present invention. Fluorescence quenching effect is not obtained, and if it is forcibly erased by administering a large amount, a large amount of AOX (adsorbable organic halogen content, hereinafter abbreviated as AOX) is contained in the post-treatment washing liquid, and this is discarded. Is extremely problematic in the environment.

[0011]

[Problems to be Solved by the Invention]
The present invention, as a result of diligent research on the production of a diazo photosensitive paper that does not fluoresce even if the waste paper pulp is contained in the base paper, as a result, the fluorescent color in the waste paper pulp is high at a stock concentration of 25% or more,
The inventors have found that the application of the fluorescence quenching agent produces a remarkable effect that cannot be predicted by known techniques, and have completed the present invention.

[0012]

The present invention relates to a diazo photosensitive paper having a diazo color forming layer containing a diazonium salt and a coupling component on the base paper, at a high density of 25% or more in the base paper. It is a diazo photosensitive paper characterized in that a waste paper pulp obtained by mixing and stirring a dye and a dichlorisocyanurate fluorescent quencher is mixed.

The raw materials for the waste paper pulp referred to in the present invention include white, ruled white, cream white, curd, and white, as shown in the waste paper standard quality table of the Waste Paper Recycling Promotion Center.
Special white, medium white, imitation, fair white, Kent, white art, special cut,
Examples include separate papers, newspapers and magazines. Further specific examples include non-coated computer paper which is information related paper, printer paper such as thermal paper and pressure sensitive paper, and OA waste paper such as PPC paper, art paper, coated paper, lightly coated paper and matte paper. Coated paper or fine paper, fine color, notebook, notepaper, wrapping paper, fancy paper, medium quality paper, newsprint, waste paper,
Waste paper such as super-wrapping paper, imitation paper, pure white roll paper, uncoated paper such as milk carton and paperboard, chemical pulp paper,
High-yield pulp-containing paper is used, but printing, copying,
It is not particularly limited whether it is printed or not.

As described above, it is recognized that sodium dichlorisocyanurate is effective in eliminating the fluorescent color of pulp without adversely affecting the pulp fibers. However, if this method is applied to recycle used paper, A
OX is generated, and AO is added to the pulp cleaning liquid after the fluorescence erasing treatment.
A large amount of X is contained and discharged, which is an environmental problem. Therefore, the present inventors have succeeded in suppressing AOX generation by the following method.

The present inventors have noticed that in the fluorescent quenching agent treatment mainly containing dichlorisocyanurate, a large amount of AOX is produced due to its excessive addition amount. In order to obtain a sufficient fluorescence quenching effect, the amount of the chemical added is increased by a conventional method, and as a result, AOX is produced. The present inventors have found that by reacting a fluorescent agent at a high stock material concentration of 25% or more, effective fluorescence quenching can be achieved with sufficient agitation even with a small addition rate of the fluorescent agent. .

By the way, in the process of producing recycled pulp, generally, (1) disaggregation: waste paper is processed by a pulper with mechanical force and chemicals to be disintegrated into fibers, and printing ink and ash are separated from the fibers. . (2) Dust removal: Remove foreign substances (plastic etc.) and dust contained in used paper with a screen, cleaner, etc. (3) Kneading: Prior to aging, a deinking agent consisting of a surfactant, a builder such as NaOH and silicate, and a bleaching agent such as hydrogen peroxide are added to the paper material and mechanically stirred to mix them. The ink is separated from the pulp fiber and dispersed. (4) Aging ... Paper materials that have undergone kneading are deinked by physicochemical reactions such as alkali swelling together with added chemicals. (5) Deinking: The ink separated and dispersed from the fibers by kneading and aging is removed from the system by a flotation method or a cleaning method. It consists of a combination of 5 steps. In the present invention, in addition to these steps, (6) Stirring: the fluorescence quenching agent is stirred at a high concentration of 25% or more in order to quench the fluorescence. In some cases, a chemical for pH adjustment is also added at the same time. (7) Reaction: A chemical quencher is added and a chemical reaction occurs after stirring.

Usually, the mixer and kneader used in the kneading step of (3) separate the ink from the fibers, and therefore it is desirable to give a compressive force to the pulp or to cause the fibers to receive an appropriate friction. Has a moderate bite between uniaxial or biaxial blades, and a kneader or disperser or a biaxial mixer, which gives a compressive force or a frictional force to fibers at a low speed, is used. In the stirring for mixing the fluorescence quencher of (6), those mixers,
Although the effect of agitation is recognized even in a kneader, in the present invention, the purpose is to uniformly mix the fluorescent quenching agent with a high-concentration pulp, not to give a compressive force or a frictional force to the fiber, and therefore it is used. It is desirable that the mixer or the kneader has a sufficient space between the uniaxial or biaxial blades so as not to give friction to the fibers, and can rotate at high speed to uniformly mix in a short time. Therefore, if it is a single axis, it is most preferable to use a mica processor that has a feed blade and a return blade in the rotor, and has a sufficient clearance with the blade of the stator and that rotates at high speed. A rotatable floater pulper may be used.

Due to this effect, the contact efficiency between the fluorescence quenching agent composed of dichloroisocyanurate and the waste paper pulp fiber dyed with the fluorescent whitening agent such as 4,4′-diaminostilbenesulfonic acid derivative is increased. The fluorescence quenching effect is enhanced. By this action, it is possible to suppress the addition of the optical brightening agent made of dichlorisocyanurate, and as a result, it is possible to reduce the AOX emission amount in the pulp cleaning liquid after the treatment. In effectively using the method of applying the fluorescence quenching agent for performing the mixing at the high concentration, the pH is preferably on the acidic side of 7.0 or less, and the temperature may be room temperature, but the extinction time depends on the temperature rise. Is shortened.

The present invention relates to penetrants such as anionic surfactants, nonionic surfactants and cationic surfactants, which are commonly used as waste paper treatment deinking chemicals, and sodium tripolyphosphate, sodium hexametaphosphate, potassium pyrophosphate, metasilicic acid. It is also possible to use soda and the like together. AOX indicates the content of organic halogen that can be adsorbed. This method is measured by TOX-10 manufactured by Mitsubishi Kasei Co., Ltd. based on the official law of the US Environmental Protection Agency.

Fluorescence is no longer observed in the diazo photosensitive paper base paper containing the recycled pulp thus produced.

The diazo photosensitive paper of the present invention can be applied to a one-component diazo photosensitive paper, a two-component multi-component diazo photosensitive paper, and the like, and in the developing system, wet development with an alkaline aqueous solution containing a coupler. The present invention can be applied to known development methods such as dry development with ammonia gas and wet dry development with organic amines.

In addition to recycled pulp, pulp used in the present invention includes NBKP, LBKP, NBSP and LBS.
P, GP, TMP and the like can be mentioned. In use, several of them are mixed and used at a ratio according to the purpose.

If desired, a filler may be added to the paper stock obtained by the method of the present invention. The type of filler can be appropriately selected and used among the internal fillers generally used in the art, as long as they do not have an alkaline component in the paper. Specifically, talc, kaolin, clay, calcined kaolin, deramikaolin, titanium dioxide, aluminosilicate, silica,
Mineral fillers such as sericite and bentonite, organic synthetic fillers and the like can be mentioned.

In addition to the above, various other anionic, nonionic, cationic, or amphoteric retention aids, which have been used conventionally, may be added to the stock in the range not impairing the desired effects of the present invention. An internal auxiliary agent for papermaking such as a water improver, a paper strength improver or an internal sizing agent is appropriately selected and used as necessary. For example, polyvalent metal compounds other than Fe, such as Al, Sn, and Zn (sulfate band, aluminum chloride), and various starches, polyacrylamide, polyethyleneimine, polyamine, polyamide polyamine, urea formalin resin, melamine formalin resin, plant gum , Polyvinyl alcohol, latex, polyethylene oxide, polyamide resin, hydrophilic cross-linked polymer particle dispersion, etc., and derivatives or modified products thereof, and one or more kinds of compounds such as colloidal silica and bentonite. Used in appropriate combination.

It is also possible to appropriately add an internal additive for papermaking such as a dye, a pH adjusting agent, a defoaming agent, a pitch control agent and a slime control agent depending on the purpose.

The papermaking method of the present invention is limited to acidic papermaking having a papermaking pH of about 4.5.
A Fourdrinier paper machine, a twin wire paper machine, a combination paper machine, a round net paper machine, a Yankee paper machine and the like can be appropriately used.

A conventional size press, a gate roll size press, a metering blade type size press, a billing blade, a short dwell coater, or the like is used to apply starch, polyvinyl alcohol, latex, maleic anhydride size to the surface of the base paper. It is also possible to apply various surface sizing agents such as styrene-acrylic acid type, dimensional stabilizers such as ethylene-urea resin, wetting agents such as polyethylene glycol and polyoxyethylene polyglyceryl ether, surfactants, pigments and dyes. Of course it is possible.

Further, the diazo photosensitive paper of the present invention can be coated with a photosensitive solution by an air knife coater, a rod coater, a curtain coater and various roll coaters.

[0029]

EXAMPLES The present invention will be described in detail below with reference to examples. The present invention is not limited to this. All parts and% in the following are by weight.

Example 1 A method for preparing an imitation waste paper pulp to be blended is shown below. The commercial imitation waste paper is disaggregated for 20 minutes at a stock material concentration of 15% (Aikawa Tekko Co., Ltd .; lab high-concentration pulper), in which 0.5% of NaOH is added to the waste paper. Next, add 30
Concentrated to 0.5% and added 0.5% NaOH as a builder, 1.5% silicate, 1.0% hydrogen peroxide as a bleaching agent, and 0.05% deinking agent (Kao; Deinking agent 600R). , Kneading 1000 times at Lab PFI Mill (Kumagaya Riki). After the kneading, the stock is packed in a polyethylene bag and heated at 60 ° C. for 2 hours. After the warm bath is finished, the stock is diluted to 1.2% and subjected to flotation with a lab flotator for 5 minutes. During this time, 1.5 minutes, 1 in 3.5 minutes
Scrap the foam layer. The stock after the flotation is washed with running water on a 100 mesh wire mesh.

This stock material was made to have a concentration of 28% and pH with a sulfuric acid band.
To 4.4, a commercially available fluorescent quenching agent (fluorionone, manufactured by Daiwa Chemical Co., Ltd.) consisting mainly of dichloroisocyanurate potassium was added to the pulp at 0, 0.5, and 1.0%, respectively, and the temperature was adjusted. Stir and mix for several seconds with a mica processor (manufactured by Ishikawajima Sangyo Kikai) at 60 ° C. Then, add 100 parts of pulp liquid.
Open it on the sieve of the mesh and wash it with the same amount of water twice. Waste paper pulp is produced by the above operation. All the water that has been squeezed and washed is collected, the AOX concentration is measured, and calculated as mg per kg of pulp. The AOX concentration was measured by TOX10 manufactured by Mitsubishi Kasei. The results are shown in Table 1.

This pulp and LBKP were blended to prepare a diazo photosensitive paper in the following order. (Base paper composition) LBKP 40 parts Imitation waste paper pulp (made above) 60 parts Talc 2 parts Rosin emulsion size agent (Dick Hercules, Newho 100) 1.4 parts Sulfate band 3 parts Amphoteric starch (Oji National Co., Ltd.) Cato3210) 0.8 part Papermaking of 1% slurry of the above composition using a TAPPI standard sheet machine, and the obtained wet paper is 5 kg /
It was pressed at cm ² and then dried at 90 ° C. for 2 minutes to obtain a base paper having a basis weight of 76 g / m ² .

The base paper was size-pressed with the following composition to obtain a base paper for diazo photosensitive paper having an adhesion amount of 0.15 g / m ² . (Combined with size press liquid) Ethylene-urea resin (Sumitomo Chemical's Sumirez resin EU) 0.5 part Polyoxyethylene polyglyceryl ether (Nippon Yushi Co., Unigri AV-670) 0.05 part Water 99.45 parts

The following diazo photosensitive solution was applied to the above diazo photosensitive paper base paper and dried to obtain a two-component diazo photosensitive paper.
Baking according to JIS P 4505 was performed using a standard original drawing for a burning test, and then ammonia development was performed. (Diazo Photosensitizer) 4-Diethylaminobenzendiazonium chloride / 1/2 zinc chloride 20 g 2,3-dihydroxynaphthalene-6-sulfonic acid sodium salt 30 g citric acid 25 g urea 20 g ethylene glycol 10 g saponin 0.5 g zinc chloride 15 g Set to 1 liter.

The fluorescence intensity of the diazo photosensitive paper containing the waste paper pulp developed as described above before and after development was measured by a measuring device manufactured by Nippon Denshoku Co., Ltd. The results are shown in Table 1.

[0036]

[Table 1]

Example 2 The AOX concentration and the residual fluorescence intensity were measured in the same manner as in Example 1 except that the stock material concentration at the time of producing waste paper pulp was 25% and the fluorescent agent addition rate was only 1% of the pulp. did. The results are shown in Table 2.

[0038]

[Table 2]

Comparative Example 1 Example 1 was repeated except that the stock concentrations were 22% and 17% at the time of producing waste paper pulp, and the fluorescent agent addition rate was 1% based on the pulp.
The AOX concentration and the intensity of residual fluorescence were measured in the same manner as in.
The results are shown in Table 3.

[0040]

[Table 3]

Example 3 The AOX concentration and the intensity of residual fluorescence were measured in the same manner as in Example 1 except that the commercially available fluorescence quenching agent containing dichloroisocyanurate as a main component was replaced by Lightnon manufactured by Meisei Chemical Co., Ltd. The results are shown in Table 4.

[0042]

[Table 4]

Comparative Example 2 The pulp after flotation was adjusted to pH with a sulfuric acid band.
To 4.4, a commercially available fluorescent quenching agent (fluorine, manufactured by Daiwa Chemical Co., Ltd.) consisting mainly of potassium dichloroisocyanurate was added to the pulp at 0, 0.5, and 1.0%, respectively, and the temperature was adjusted. A diazo photosensitive paper is prepared and evaluated in the same manner as in Example 1 except that the magnetic stirrer is gently stirred at 60 ° C. for 30 minutes. The results are shown in Table 5.

[0044]

[Table 5]

Comparative Example 3 Evaluation was carried out in the same manner as in Comparative Example 1 except that the commercially available fluorescent erasing agent mainly composed of potassium dichloroisocyanuric acid was used as the fluorescent erasing agent, except Lighton (manufactured by Meisei Chemical Co., Ltd.). The results are shown in Table 6.

[0046]

[Table 6]

Comparative Example 4 Table 7 shows the measurement results of the fluorescence intensity of commercial virgin pulp and the fluorescence intensity of commercial waste paper pulp. This example is shown only for comparison of non-fluorescence and fluorescence.

[0048]

[Table 7]

As mentioned above, 25% of mica processor
Residual fluorescence is not observed in the diazo photosensitive paper prepared by using waste paper pulp stirred at a concentration higher than the above. Further, the AOX emission amount at the time of preparation is sufficiently reduced as compared with the case where the magnetic stirrer is used. The same effect can be observed even if the type of fluorescent quenching agent is changed.

Example 4 In addition to the fluorescent quenching agent, 0.03% of a surfactant (deinking agent 800R manufactured by Kao Corporation), 1.0% of hydrogen peroxide, and sodium metasilicate 2 were added to pulp. The treatment was performed in the same manner as in Example 1 except that 0.0% was added, and the AOX concentration and the intensity of residual fluorescence were measured. The results are shown in Table 8.

[0051]

[Table 8]

As described above, the same effect can be observed by adding a surfactant, hydrogen peroxide, and sodium silicate to the fluorescent quenching agent.

Example 5 The same treatment as in Example 1 was carried out except that the temperature was fixed at 20 ° C., the fluorescent agent addition rate was fixed at 1.0%, the addition amount of the sulfuric acid band was adjusted to change the pH of the stock material. The AOX concentration and the intensity of residual fluorescence were measured. The results are shown in Table 9.

[0054]

[Table 9]

Treatment with a paper stock pH of 7 or less is preferable for fluorescence elimination, and reduction of AOX emission is good even in this state.

Example 6 AOX was treated in the same manner as in Example 1 except that the pH was fixed at 4.5 and the addition ratio of the fluorescent agent was fixed at 1.0% and various temperatures were adjusted.
The concentration and the intensity of residual fluorescence were measured. The results are shown in Table 10.

[0057]

[Table 10]

A treatment at a stock temperature of 20 ° C. or higher is preferable in terms of erasing fluorescence, and reduction of AOX emission is good even in this state.

[0059]

As is apparent from Tables 1 to 10, even if the base paper of the diazo photosensitive paper contains the waste paper pulp, the present invention can detect the fluorescence by eliminating the residual fluorescence in the waste paper pulp. It is possible to manufacture a diazo photosensitive paper that does not have this.

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Claims (4)

[Claims] 1. A diazo photosensitive paper having a diazo coloring layer containing a diazonium salt and a coupling component on the base paper, wherein the base paper and dichlorisocyanuric acid are added to the base paper at a high concentration of 25% or more. A diazo photosensitive paper characterized by being mixed with a waste paper pulp which is mixed and stirred with a salt fluorescent quencher. 2. The diazo photosensitive paper according to claim 1, wherein at least one selected from a kneader, a mica processor, and a floater pulper is used as the mixing stirrer. 3. A paper material containing one or more penetrants selected from anionic surfactants, nonionic surfactants, and cationic surfactants, and sodium tripolyphosphate, sodium hexametaphosphate, potassium pyrophosphate, sodium metasilicate. The diazo photosensitive paper according to claim 1, which is used in combination with at least one selected from the group consisting of: 4. The diazo photosensitive paper according to claim 1, 2 or 3, wherein the pH of the paper material is 7 or less.