JP4260582B2 - Deinking additive - Google Patents

Description

  The present invention relates to a deinking additive and a deinking agent used when recycling used paper such as newspapers and magazines.

  Due to changes in the deinking environment in recent years, such as changes in raw paper, changes in printing technology (printing method, printing ink components, etc.), changes in deinking equipment, etc., the performance required for deinking agents has become diversified and sophisticated. Therefore, there is an increasing demand for a deinking agent that has a stronger ink collecting property and a better foaming property. Fatty acid salts are deinking agents that are being reconsidered in the industry because they have good ink collecting properties and good foaming properties.

As a technique using fatty acid salt (soap) or fatty acid, saturated fatty acid soap or saturated fatty acid (which becomes a soap with an alkaline agent in the system) that is the strongest and excellent in foaming properties as an ink collector and an ink stripping agent or a starting agent. A combination with a foaming agent is disclosed in Patent Document 1 and the like, and a combination of a fatty acid and an alkylene oxide adduct of an alcohol or a combination of a compound and an ink releasability increase, and an improvement in the quality of regenerated pulp by improving ink collection performance Yes. In addition, as disclosed in Patent Document 2 and the like, a technique for improving operability as an O / W emulsion by using a fatty acid in combination with a nonionic surfactant or an anionic surfactant is also known. Furthermore, Patent Document 3 obtains a deinking agent that does not impair the ability to collect saturated fatty acid ink, improves the operability by making the product form a liquid, and improves the deinking quality of recycled pulp. Therefore, it is described that a fatty acid mixture containing a saturated fatty acid having a total carbon number of 12 to 14 as an essential component is dissolved with a nonionic surfactant to form a liquid composition.
JP 62-250291 A JP-A-5-501286 Patent No. 2992210

  Patent Document 3 provides a deinking agent that is liquid and easy to operate, and has excellent deinking performance. Today, the ratio of leaflets and magazines in the used wastepaper has increased, and the foaming properties of the wastepaper itself in the deinking process have increased. Since there is a tendency to increase, sufficient deinking performance may be difficult to express. In addition, with the increase in the deinking pulp blending ratio, it has been required to improve the deinking performance of the deinking agent, such as deinking properties and the ability to reduce adhesives.

  An object of the present invention is to provide a deinking agent having further improved deinking performance, particularly deinking properties and adhesive material reducing properties.

  The present invention contains 40 to 50% by weight of saturated fatty acid having 12 carbon atoms and unsaturated fatty acid, and the weight ratio of saturated fatty acid (a1) to unsaturated fatty acid (a2) is (a1) / (a2) = 90 / A deinking additive comprising a fatty acid mixture (a) [hereinafter referred to as component (a)] of 10 to 75/25 is provided.

  The present invention also includes 40 to 50% by weight of saturated fatty acid having 12 carbon atoms and unsaturated fatty acid, and the weight ratio of saturated fatty acid (a1) to unsaturated fatty acid (a2) is (a1) / (a2) = A deinking agent comprising a fatty acid mixture (a) of 90/10 to 75/25 and a nonionic surfactant (b) having an HLB of 2 to 12 is provided. The deinking agent of the present invention provides a deinking method in which (a) and (b) of the deinking agent are added before the flotation step.

  ADVANTAGE OF THE INVENTION According to this invention, the deinking additive and deinking agent which are excellent in deinking property and adhesive reduction property, and can obtain the deinking pulp with high whiteness and few adhesives are provided.

  When used as a deinking agent, long-chain saturated fatty acids have a strong ink collecting ability but are solid at room temperature and poor in operability. For this reason, it is necessary to set the system temperature to the melting point or higher in the deinking process, and the energy consumption is high, and also the adhesive is softened, and the adhesive tends to be brought into the papermaking process. There is. In addition, since the ink collecting power is strong, the adhesive that could not be removed may become entangled with the ink and become coarse and cause problems with the adhesive. This tendency is more remarkable as the alkyl group of the fatty acid is longer. On the other hand, the unsaturated fatty acid has a good dispersion effect on the adhesive and has no problem of coarsening. However, since the ink collecting ability is weak, there is a limit to obtaining excellent performance alone.

  In the present invention, the component (a) constituting the deinking additive contains 40 to 50% by weight of a saturated fatty acid having 12 carbon atoms and an unsaturated fatty acid, and the saturated fatty acid (a1) and the unsaturated fatty acid (a2 ) Weight ratio of (a1) / (a2) = 90/10 to 75/25, the advantages and disadvantages of fatty acids are made uniform, ink collecting power, foaming properties, and adhesives An additive for deinking that exhibits a good balance between reduction and operability is obtained.

  In the deinking system, the foaming level required for the deinking agent differs depending on the used raw paper or the rotator model, which may cause operational troubles. In addition, the degree of deterioration of waste paper and the difference in mechanical strength of pulpers or kneaders affect the degree of fineness of the ink. If the fineness of the ink leads to a decrease in whiteness, fatty acids and nonionic surfactants You can control them in proportion. For example, in a high foaming system, a fatty acid having a low foaming property or a high ratio is suitable. In a low foaming system, it is difficult to foam, and therefore a nonionic surfactant is preferably used for the purpose of foaming. Moreover, the one where a fatty acid ratio is higher can suppress refinement | miniaturization of ink.

  The component (a) can be used alone as a deinking agent, but can also be used as an auxiliary agent used in combination with other surfactants used as a deinking agent, including the component (b) of the present invention.

Among the components (a), the saturated fatty acid (a1) has 8 to 22 carbon atoms, more preferably 12 to 18 carbon atoms, and in the fatty acid mixture (a) , the ratio of 12 saturated fatty acids to 40 to 50% by weight, 43 to 48% by weight is preferred. The unsaturated fatty acid (a2) has preferably 12 to 18 carbon atoms, more preferably 16 to 18 carbon atoms.

  In the present invention, the weight ratio of the saturated fatty acid (a1) to the unsaturated fatty acid (a2) is (a1) / (a2) = 90/10 to 75/25, more preferably 85/15 to 80/20.

  The component (a) of the present invention has a titer (melting point: JIS K-0065) in the range of 10 to 50 ° C, preferably in the range of 20 to 45 ° C. Within this titer range, unsaturated fatty acids, polymerized fatty acids, and resin acids may be included.

  In the present invention, in order to improve foamability and ink releasability, a nonionic surfactant as the component (b) can be used in combination with the component (a).

  As the component (b), one having an ink peeling action and recognized as a deinking agent is used. Nonionic surfactants are compounds obtained by random addition or block addition of alkylene oxides having 2 to 4 carbon atoms (hereinafter abbreviated as AO) to alcohols, amides or fatty acids having active hydrogen. Or those fatty acid esterified products are preferred, and alcohol-based nonionic surfactants are particularly preferred. Specific examples include the following.

(1) Alcohol-based nonionic surfactant An alkylene oxide adduct of a saturated or unsaturated primary or secondary alcohol having 8 to 24 carbon atoms or an alkylphenol having 8 to 12 carbon atoms in total Is mentioned. As the constituent alcohol, myristyl alcohol and stearyl alcohol are preferable. Examples of AO added to alcohol include ethylene oxide (hereinafter abbreviated as EO), propylene oxide (hereinafter abbreviated as PO), and butylene oxide, and it is particularly desirable to make EO essential. The number of moles of AO added is preferably 3 to 200 moles, particularly 10 to 80 moles per mole of alcohol or alkylphenol. In this range, a nonionic surfactant having particularly good ink releasability and easy liquefaction is obtained. It is done. The addition form may be either random addition or block addition.

(2) Fatty acid-based nonionic surfactants include AO adducts of saturated or unsaturated higher fatty acids having a total carbon number of 10 to 24. Examples of higher fatty acids include lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, and behenic acid. Examples of unsaturated fatty acids include palmitoleic acid, oleic acid, elaidic acid, linoleic acid, linolenic acid, erucic acid, ricinoleic acid and the like. The kind of AO and the number of added moles are the same as above.

(3) Amine-based nonionic surfactants AO adducts of saturated or unsaturated primary or secondary amines having a total carbon number of 8 to 36 can be mentioned. Examples of amines include 2-ethylhexylamine, di-2-ethylhexylamine, laurylamine, dilaurylamine, tetradecylamine, ditetradecylamine, hexadecylamine, dihexadecylamine, stearylamine, distearylamine, oleylamine, diamine And oleylamine. The kind of AO and the number of added moles are the same as above.

(4) Ester-Oil and Fat Nonionic Surfactant AO adduct of a mixture of an oil and fat consisting of an ester of a saturated or unsaturated fatty acid having a total carbon number of 8 to 24 and glycerine and a divalent to 10-valent polyhydric alcohol Is mentioned. Examples of the fatty acid include those exemplified in the above (2). Examples of the divalent to 10-valent polyhydric alcohol include ethylene glycol, propylene glycol, glycerin, polyglycerin, sorbitol, sorbitan, and sucrose. The kind of AO and the number of added moles are the same as above.

  In addition to these nonionic surfactants, any other component having suitable properties as a deinking agent can be used as the component (b). The component (b) has an HLB of 2 to 12 by Davies, and those in the range of 3 to 10 are preferably used.

  In the present invention, the ratio of the component (a) to the component (b) is preferably in the range of (a) / (b) = 10/90 to 40/60, more preferably 15/85 to 30/70, by weight. Within this range, solidification / separation is suppressed, liquefaction is facilitated, and ink releasability, ink collecting properties, and foaming properties are improved.

  The content of the component (b) in the deinking agent of the present invention after satisfying the above (a) / (b) weight ratio is 40 to 90% by weight, more preferably 60 to 85% by weight, particularly 65 to 80% by weight. % Is preferred.

  Further, the sum of the components (a) and (b) in the deinking agent of the present invention is preferably 60 to 100% by weight, more preferably 70 to 100% by weight, and particularly preferably 85 to 100% by weight.

  The deinking agent of the present invention can be a liquid composition. In particular, when the component (a) and the component (b) are used in combination, liquefaction is easy. At that time, dissolution of the fatty acid mixture can be promoted by adding water. However, if the amount of water is too large, the liquid composition may thicken or solidify, so the amount of water is preferably 40% by weight or less in the liquid composition, more preferably 5 to 20%. % By weight.

  Further, the method for producing the liquid composition containing the component (a) and the component (b) is not limited, but each component is charged in a lump and once heated to the melting point of the fatty acid mixture of the component (a) and mixed. A method in which the fatty acid is sufficiently dissolved and then cooled to around room temperature. It is preferable that the deinking agent of the present invention does not precipitate fatty acid crystals at room temperature and does not cause separation / solidification or crystal precipitation due to temperature change.

  The liquid composition serving as the deinking agent of the present invention preferably has a liquefaction index in the range of 0.8 to 1.2, more preferably 0.9 to 1.1. Here, the “liquefaction index” is calculated by the following method. First, a liquid composition in which a fatty acid mixture is dissolved in a nonionic surfactant is prepared, placed in a suitable cylindrical container and allowed to stand at room temperature for a certain period of time. / 10 (volume basis) of liquid is collected and each acid value (JIS K-3504) is measured. From this value, the ratio of [Upper acid value] / [Lower acid value] is determined and used as the liquefaction index. As the liquefaction index approaches 1, it means that the solution is more uniformly dissolved (or dispersed in some cases).

  The deinking agent of the present invention may be added before the flotation step, that is, any of the waste paper disaggregation step, the kneader treatment step, the aging tower step and the flotation treatment step, or divided into each step. When added to a place having a high shearing force, such as a kneader treatment step, the effect is highest. The amount added is preferably 0.05 to 1.0% by weight based on the raw paper.

  In addition to adding the deinking agent containing the components (a) and (b), the components (a) and (b) are not mixed in advance and may be added separately before the flotation step. The effect of the present invention can be obtained even by such a method.

  In addition, the deinking agent of the present invention may be used in combination with a known deinking agent that has been conventionally used, for example, higher alcohol sulfates, polyoxyalkylene higher alcohol sulfates, alkylbenzene sulfonates, etc., if necessary. Is also possible.

Example 1 [(a) component single system]
Using the fatty acid mixture shown in Table 1 as a deinking agent, the ink was deinked by the following method to evaluate the whiteness and the adhesive. The results are shown in Table 2.

  Waste paper (newspaper / flyers / magazines = 55/35/10, weight ratio) is shredded into 2cm x 5cm, then placed in a desktop disintegrator, where 1% sodium hydroxide (waste paper weight%), sodium silicate 3% (waste paper weight%), hydrogen peroxide 1% (waste paper weight%), deinking agent in Table 2 in terms of effective amount [total of component (a)] 0.3% (waste paper weight%), and Water was added and the mixture was disaggregated for 10 minutes at 40 ° C. with a pulp concentration of 15% by weight. Further, after ripening at 40 ° C. for 60 minutes, water was added to a pulp concentration of 1% by weight, and then a flotation treatment was performed at 40 ° C. for 10 minutes using a Voith-IHI Eco-Flotter. The pulp slurry after the flotation was concentrated to a concentration of 10% by weight, and then water was added to return it to a concentration of 1% by weight. A pulp sheet was prepared with a tappy sheet machine and dried by ventilation. The whiteness of the obtained pulp sheet was measured with a whiteness meter.

  On the other hand, with respect to the amount of the sticky substance, 10 g of the pulp slurry after the flotation treatment was taken as dry pulp, processed using a master screen device (4cut slit screen) manufactured by Palmac, and the residue was received on filter paper. . PPC paper (copy paper) was stacked on it, dried with a drum dryer, and further subjected to heat press treatment at 150 ° C., 175 ° C., 0.5 MPa for 2 minutes to transfer the adhesive. Next, the filter paper and the PPC paper were peeled off, excess fiber on the transferred PPC paper side was peeled off with a brush, and the number of the remaining adhesives was measured with a dirt counter meter.

(Note) In the table, the next number of C is the number of carbon atoms, and the next number of F represents the number of unsaturated bonds (the same applies hereinafter).

Example 2 [(a) component, (b) component combined use system]

  Raw paper (newspaper / flyers / magazines = 55/35/10, weight ratio) is shredded into 2cm x 5cm, then placed in a desktop disintegrator, where sodium hydroxide 0.5% (waste paper weight%), Table 3 The deinking agent was 0.2% (total weight of component (a) and component (b)) 0.2% (waste paper weight%) and water was added, and the pulp concentration was 15% by weight at 40 ° C. for 10 minutes. Next, dehydration is performed to obtain a pulp concentration of 25% by weight, and further sodium hydroxide 0.5% (waste paper weight%), sodium silicate 2% (waste paper weight%), hydrogen peroxide 0.5% (waste paper weight%), The deinking agent in Table 2 was added in an amount of 0.05% (total weight of component (a) and component (b)) and kneaded after aging at 60 ° C for 120 minutes. The flotation treatment was performed using the MT-flotator manufactured by Voith-IHI under the condition of 1.

  Moreover, about the deinking agents of Examples 2-5 to 2-9 and Comparative Examples 2-9 to 2-14 in Table 3, the liquefaction index at 10 ° C. was measured. However, a liquid composition (90% by weight of (a) + (b) and 10% by weight of water) prepared by dissolving the component (a) in the component (b) and water was used for the measurement.

(Note) In the table, EO and PO numbers are the average number of moles added. In (b) nonionic surfactant, [] represents random addition, and the terminal hydrogen atom is omitted. Separate addition means that the component (a) and the component (b) are added separately, and the compounding addition means that the component (a) and the component (b) are mixed and added in advance.

Claims (9)

A deinking additive comprising a fatty acid mixture (a) composed of fatty acids having 8 to 18 carbon atoms,
The fatty acid mixture (a) includes a saturated fatty acid (a1) having 8 to 18 carbon atoms and an unsaturated fatty acid (a2) having 12 to 18 carbon atoms, and a saturated fatty acid (a1) having 8 to 18 carbon atoms and the carbon number The weight ratio of 12-18 unsaturated fatty acids (a2) is (a1) / (a2) = 90 / 10-75 / 25,
The fatty acid mixture (a) contains 40 to 50% by weight of saturated fatty acid having 12 carbon atoms,
Additive for deinking agents. The additive for deinking agents according to claim 1, wherein the fatty acid mixture (a) has a titer (melting point: JIS K-0065) in the range of 20 to 45 ° C. Fatty composed fatty acid mixtures from the carbon number 8 to 18 (a) and HLB is a deinking containing a nonionic surfactant of 2 to 12 (b),
The fatty acid mixture (a) includes a saturated fatty acid (a1) having 8 to 18 carbon atoms and an unsaturated fatty acid (a2) having 12 to 18 carbon atoms, and a saturated fatty acid (a1) having 8 to 18 carbon atoms and the carbon number The weight ratio of 12-18 unsaturated fatty acids (a2) is (a1) / (a2) = 90 / 10-75 / 25,
The fatty acid mixture (a) contains 40 to 50% by weight of saturated fatty acid having 12 carbon atoms,
Deinking agent. The deinking agent according to claim 3, wherein the weight ratio of (a) / (b) is 10/90 to 40/60. The deinking agent according to claim 3 or 4, wherein (b) is an alcohol-based nonionic surfactant. The alcohol-based nonionic surfactant is an alkylene oxide adduct of a saturated or unsaturated primary or secondary alcohol having 8 to 24 carbon atoms in total or an alkylene oxide adduct of an alkylphenol having 8 to 12 carbon atoms in total. The deinking agent according to claim 5. The deinking agent according to claim 6, wherein the number of moles of alkylene oxide added per mole of the alcohol or the alkylphenol is 3 to 200 moles. The deinking agent according to any one of claims 3 to 7 , wherein the fatty acid mixture (a) has a titer (melting point: JIS K-0065) in the range of 20 to 45 ° C. A deinking method in which (a) and (b) of the deinking agent according to any one of claims 3 to 8 are added before the flotation step.