JP4637544B2 - Paper coating composition material, method for producing the same, and paper coating composition - Google Patents

Description

  The present invention relates to a paper coating composition material, a method for producing the same, and a paper coating composition.

  In recent years, awareness of the environment has increased, and activities aimed at realizing an environmentally harmonious society have been carried out on a global scale in harmony with nature and in harmony with each other. In such a trend, various natural materials are attracting attention as materials that have a low environmental impact instead of conventional petroleum-based raw materials.

  An object of this invention is to provide the material for paper coating compositions which use egg white as a raw material, its manufacturing method, and a paper coating composition.

  The present inventor has found that egg white can be used as a raw material for the paper coating composition. In addition, the inventor of the present application has found an egg white excellent in bubble stability and a method for producing the egg white, and by using the egg white excellent in bubble stability as a raw material for the paper coating composition, it is thick, light, and less transparent. The present inventors have found that it is possible to produce a paper that is easy to turn and has a good feel and texture.

  The paper coating composition material of the present invention contains egg white and water having a mass 1 to 3 times that of the egg white. In the present invention, “egg white” generally means a solid concentration of about 12% by mass.

  The paper coating composition material of the present invention contains egg white and water having a mass 1 to 3 times that of the egg white, and is obtained by heating at 75 to 98 ° C. at a pH of 9.5 to 11.5. . In the paper coating composition material of the present invention, it can be in a foamed state.

  The material for paper coating composition of the present invention comprises an egg white and an egg white aqueous solution containing 1 to 3 times as much water as the egg white heated at 75 to 98 ° C. at a pH of 9.5 to 11.5. It is obtained by drying the egg white aqueous solution.

  In the material for paper coating composition of the present invention, the pH can be 8-11.

  In the material for paper coating composition of the present invention, the viscosity can be 1 to 100 mPa · s.

  In the material for paper coating composition of the present invention, in the band pattern obtained by non-SDS polyacrylamide gel electrophoresis, ovalbumin in the material for paper coating composition obtained by measurement with a digital gel imager The peak area of the band 1 is 20% or less of the peak area of the band of ovalbumin 1 in the diluted raw egg white solution having the same protein concentration obtained by the measurement by the digital gel imager, and by the digital gel imager The peak area of the ovotransferrin band in the paper coating composition material obtained by the measurement is the peak of the ovotransferrin band in the diluted raw egg white solution having the same protein concentration obtained by the measurement by the digital gel imager. It can be 20% or less of the area.

  In the paper coating composition material of the present invention, the electric conductivity can be 4 to 15 mS / cm.

  In the material for paper coating composition of the present invention, after foaming so that the foam density is 0.08 to 0.15 g / ml, the residual amount of foam when left at 25 ° C. for 3 hours is 70. % (V / v) or more. In the present specification, the “foam density” refers to the density of the foamed material for a paper coating composition of the present invention. This foam density is obtained by dividing the mass of the foamed paper coating composition material of the present invention by the volume of the foamed paper coating composition material of the present invention.

  In the material for paper coating composition of the present invention, after foaming so that the foam density is 0.08 to 0.15 g / ml, the water separation amount when left at 25 ° C. for 3 hours is 7% ( v / v) or less. In the present specification, the “water separation amount” refers to the amount of liquid to be separated after the foamed material for paper coating composition of the present invention is allowed to stand at a predetermined temperature for a predetermined time. This “water separation amount” represents the volume of the separated liquid as a percentage with respect to the volume of the foamed material for paper coating composition of the present invention. For example, “the water separation amount is 7% (v / v)” means that “when the volume of the foamed material for paper coating composition of the present invention is 100 ml, for example, the volume of the separated liquid is 7 ml. Means.

  In the paper coating composition material of the present invention, egg white that has been subjected to desugaring treatment can be used as the egg white.

  The material for paper coating composition of the present invention can be reduced in allergenicity. In this case, in the material for paper coating composition of the present invention, the mass of unmodified ovalbumin per solid content can be 5 mg / g or less. In the present specification, the “mass of unmodified ovalbumin per solid content” refers to the mass of unmodified ovalbumin in the solid content of the material for paper coating composition of the present invention. Therefore, “the mass of the unmodified ovalbumin per solid content is 5 mg / g or less” means that the unmodified ovalbumin is 5 mg or less per 1 g of the solid content of the material for paper coating composition of the present invention. Means included.

  The paper coating composition of this invention contains the material for paper coating compositions in any one of the said.

  The method for producing a material for paper coating composition of the present invention comprises the steps of preparing an egg white aqueous solution by diluting egg white with water 1 to 3 times the mass of the egg white, and adjusting the egg white aqueous solution to pH 9.5 to 11. 5 and heating at 75 to 98 ° C.

  The manufacturing method of the material for paper coating compositions of this invention can further include the process of adjusting the said egg white aqueous solution to pH 8-11 after the said heating process.

  The method for producing a material for paper coating composition of the present invention may further comprise a step of foaming the egg white aqueous solution.

  The manufacturing method of the material for paper coating compositions of this invention can further include the process of desugaring the egg white using the said egg white aqueous solution previously.

  The paper coating composition material of the present invention contains egg white and water having a mass 1 to 3 times that of the egg white. Moreover, the paper coating composition material of the present invention contains egg white and water having a mass of 1 to 1.5 times that of the egg white, and is heated at 75 to 98 ° C. at a pH of 9.5 to 11.5. Can be obtained. The material for paper coating composition of the present invention is excellent in the stability of bubbles, and the bubbles are composed of fine bubbles. Therefore, by using the paper coating composition material of the present invention as a raw material of the paper coating composition, it is possible to produce a paper that is thick, light, difficult to see through, easily turned, and has a good hand feeling and texture. it can. Moreover, since the material for paper coating compositions of this invention is egg white which is a non-petroleum-type natural raw material, it is a low load with respect to an environment. For example, the paper coating composition material of the present invention can be suitably used for producing bulky paper.

  Moreover, the manufacturing method of the material for paper coating compositions of this invention has the process of diluting egg white with the water of 1 to 3 times the mass of said egg white, and preparing egg white aqueous solution, and said egg white aqueous solution is pH 9.5. Heating at 75-98 ° C. at 11.5. According to the method for producing a paper coating composition material of the present invention, a paper coating composition material having excellent bubble stability and containing fine bubbles can be easily produced.

1. Paper coating composition material and method for producing the same The paper coating composition material of the present invention contains egg white and water having a mass 1 to 3 times that of the egg white. Here, the amount of the water is more preferably 1.3 to 2 times.

  Examples of the egg white used in the paper coating composition material of the present invention include raw egg white, frozen egg white, dried egg white, and egg white from which specific egg white proteins (for example, lysozyme) have been removed. Raw egg white is obtained by splitting a chicken egg or the like and separating the yolk.

  In addition, as described above, in the present invention, “egg white” means one having a solid content concentration of about 12% by mass. Therefore, for example, when dry egg white is used, the solid content concentration is about 12% by mass. Thus, what is obtained by adding water to dried egg white corresponds to the egg white of the present invention. That is, when dry egg white is used, the paper coating composition material of the present invention has a solid content concentration of about 12% by mass when (A): dry egg white and (B): (A) are dissolved. It is possible to contain water necessary to make the water and water having a mass 1 to 3 times that of (C): {(A) + (B)}.

  Moreover, the egg white may have been subjected to a desugaring treatment with yeast, bacteria or enzymes, for example. Browning can be prevented by subjecting the egg white to a desugaring treatment. Thereby, white paper can be obtained by manufacturing paper using the material for paper coating compositions of this invention using the egg white which performed the desugaring process previously.

  The desugared egg white preferably has a free glucose of 0.4 mg / ml or less, and more preferably 0.2 mg / ml or less. Here, the concentration (mg / ml) of free glucose indicates the mass (mg) of free glucose contained in an egg white aqueous solution (ml) having a solid content concentration of 12%. Here, the egg white aqueous solution having a solid content concentration of 12% may be the egg white itself or the egg white which has been reconstituted.

  The concentration of free glucose is measured using, for example, Medisafe Reader GR-101 (trade name, manufactured by Terumo Corporation), Medisafe Chip MS-GC25 (blood glucose test measurement chip) (trade name, manufactured by Terumo Corporation). be able to. For example, a chip is attached to a Medisafe reader, and an aqueous solution of egg white having a solid content concentration of 12% is attached to the chip and the concentration of free glucose is measured.

  The material for paper coating composition of the present invention also contains egg white and water 1 to 3 times the mass of the egg white, and is obtained by heating at 75 to 98 ° C. at a pH of 9.5 to 11.5. It is done.

  That is, the method for producing a material for a paper coating composition of the present invention includes a step of diluting egg white with water having a mass 1 to 3 times that of the egg white to prepare an egg white aqueous solution, and the pH of the egg white aqueous solution is 9.5. Heating at 75-98 ° C. at 11.5. The heating time is preferably 5 to 15 minutes after reaching the temperature. In addition, the method may further include a step of desugaring the egg white using the egg white aqueous solution in advance. In addition, the paper coating composition material of the present invention can be obtained as a dry (or dry) powder by drying after heating.

  Here, when the water used for the paper coating composition material of the present invention has a mass less than 1 times that of egg white, the egg white may solidify upon heating, whereas for the paper coating composition of the present invention. When the water used for the material has a mass exceeding 3 times that of egg white, the effect of the present invention is not achieved. Further, when the egg white is dried after heating, the operation cost is undesirably high. The amount of water is more preferably 1.3 to 2 times.

  In the heating step, if the heating temperature is less than 75 ° C, the egg white may not be sufficiently denatured. On the other hand, if the heating temperature exceeds 98 ° C, the resulting paper coating composition material may be browned. is there.

  Moreover, in the said heating process, when pH is less than 9.5, egg white may aggregate, and when pH exceeds 11.5, the material for paper coating compositions obtained may brown. is there.

  Egg white usually includes proteins (egg white protein) such as ovalbumin, ovotransferrin, ovomucoid, lysozyme, ovomucin, ovoglobulin, ovoglycoprotein, ovoinhibitor, ovomacroglobulin, ovoflavoprotein, avidin, cystatin. Further, the chemical structure of these egg white proteins includes functional groups such as a carboxyl group, a carbonyl group, an amino group, an amide group, a disulfide group, a hydroxyl group, a mercapto group, and a guanidino group. The above functional groups are present as terminal groups of tyrosine, arginine, lysine, histidine, tryptophan, cysteine, glutamine, asparagine and the like among amino acids constituting egg white protein. Of the above functional groups, the mercapto group (-SH) exists only in ovalbumin, and the disulfide group (-SS-) is formed by sulfur atoms of two amino acids (cysteine) constituting egg white protein. . Egg white protein in egg white can be denatured by the heating step. Thereby, a soluble heat aggregate is produced, and it is considered that this soluble heat aggregate contributes to the bubble stability of the material for paper coating composition of the present invention.

  Moreover, the pH of the material for paper coating compositions of this invention can be 8-11 by adding an acidic compound or a basic compound according to the pH of the said egg white aqueous solution after the said heating process. A pH within the above range is suitable as a paper-coated paper material. If the pH of the material for paper coating composition of the present invention is acidic, aggregates may be precipitated, and if it is neutral, the viscosity becomes too high and it is difficult to coat the paper coated paper material. If it is alkaline, it may be browned. A more preferable pH range is 9-10.

  In the present invention, the pH can be adjusted using an acidic compound or a basic compound. The pH of an egg white aqueous solution obtained by dissolving egg white in water is usually neutral to weakly basic. In order to increase the pH of the egg white aqueous solution (for example, pH 9.5 to 11.5), a basic compound is added to the egg white aqueous solution. For example, in order to lower the pH of an egg white aqueous solution having a pH of 9.5 to 11.5, an acidic compound is added to the egg white aqueous solution. In order to prevent a rapid pH change of the egg white aqueous solution, it is desirable to dilute the acidic compound or the basic compound with water to obtain an aqueous solution, and add this aqueous solution to the egg white aqueous solution.

  Although it does not specifically limit as an acidic compound, For example, an acetic acid, a citric acid, tartaric acid, a succinic acid, malic acid etc. can be mentioned as an organic acid. Examples of inorganic acids include hydrochloric acid, sulfuric acid, and phosphoric acid. These may be used alone or in combination of two or more.

  Although it does not specifically limit as a basic compound, Sodium carbonate, sodium hydrogencarbonate, sodium hydroxide, trisodium phosphate, potassium hydroxide etc. can be mentioned. These may be used alone or in combination of two or more.

  In the manufacturing method of the material for paper coating compositions of this invention, the process of desugaring the egg white using the said egg white aqueous solution previously can further be included. Thereby, browning of the material for paper coating compositions obtained can be prevented.

  The paper coating composition material of the present invention can be in a foamed state. That is, when the material for paper coating composition of the present invention is used as a raw material for the paper coating composition, the material for paper coating composition of the present invention can be used after foaming. Since the paper coating composition material of the present invention is excellent in the stability of bubbles and contains fine bubbles, the paper coating composition in a state where the paper coating composition material of the present invention is foamed. By using it, the physical property suitable as a material for paper coating compositions is obtained. That is, it is possible to produce a paper that is thick, light, difficult to see through, easily turned, and has a good feel and texture. In particular, the material for paper coating composition of the present invention can be suitably used for producing bulky paper.

  The paper coating composition material of the present invention can be foamed by stirring or aeration. Here, the stirring method, the type of the stirring device, and the rotation speed of the stirring device are not particularly limited, and can be appropriately selected according to the amount and type of the material to be stirred. Examples of the stirrer include a kitchen aid mixer (manufactured by Kitchen Aid) and a Hobart mixer (manufactured by Hobart). As for aeration, a method of foaming by sending compressed air can be exemplified, and as equipment, for example, “MONDIMIXER (trade name)” manufactured by APV Crepaco, “Overrun Machine (trade name)” manufactured by Izumi Food Machinery Co., Ltd. Examples of the whipping apparatus such as a batch type or a continuous type, or a combination thereof, are not limited to these.

  Further, the paper coating composition material of the present invention may be stirred to foam and then mixed with the paper coating composition, or the paper coating composition material of the present invention may be mixed with other paper. The material for paper coating composition of the present invention may be foamed in the paper coating composition by mixing with the raw material of the coating composition and stirring.

  Moreover, the paper coating composition material of the present invention can have a viscosity of 1 to 100 mPa · s. When the viscosity is within this range, it can be uniformly mixed with other raw materials contained in the paper coating composition, so that the paper coating composition can be uniformly coated on the paper. Moreover, a more preferable viscosity is 1-50 mPa * s.

  Further, the paper coating composition material of the present invention is a band pattern obtained by non-SDS polyacrylamide gel electrophoresis, wherein the paper coating composition material is obtained by measurement with a digital gel imager. The peak area of the band of ovalbumin 1 (OVA1) is 20% or less (preferably 10%) of the peak area of the band of ovalbumin 1 in a raw egg white diluted solution having the same protein concentration obtained by measurement with a digital gel imager. The peak area of the ovotransferrin band in the paper coating composition material obtained by measurement with a digital gel imager is the same protein concentration obtained by measurement with a digital gel imager. 20% or less of the peak area of the ovotransferrin band in the diluted raw egg white solution Under (preferably 15% or less). Here, the peak area of each band is obtained by integrating the pixel intensity distribution of each band.

  Ovalbumin and ovotransferrin are the main egg white proteins contained in normal raw egg white as described above. Polyacrylamide gel electrophoresis is electrophoresis performed in a gel polymerized with acrylamide, and non-SDS polyacrylamide gel electrophoresis is polyacrylamide gel electrophoresis that does not use SDS (sodium dodecyl sulfate).

  By using a digital gel imager, for example, by analyzing the image obtained by photographing a gel band with a digital camera and digitizing the density of the band, the pixel intensity relative to the band position (Pixel Position) (Pixel Intensity) can be obtained.

  For example, using a digital gel imager, the amount of ovalbumin and ovotransferrin can be relatively compared from the bands of ovalbumin and ovotransferrin in the band pattern obtained by polyacrylamide gel electrophoresis. In addition, in electrophoresis for the paper coating composition material of the present invention, since it is a system that does not contain SDS, monomerization of polymerized molecules does not occur, so it is included in the paper coating composition material of the present invention. The native protein can be accurately detected.

  Further, the paper coating composition material of the present invention can have an electric conductivity of 4 to 15 mS / cm. When the electrical conductivity is 15 mS / cm or less, aggregation of egg white protein can be prevented. Thereby, it can mix with the other raw material of paper coating composition, without producing a deposit or precipitation. In the paper coating composition material of the present invention, if the electrical conductivity is less than 4 mS / cm, the dilution factor becomes too large, and the effects of the present invention may not be achieved. Moreover, although electrical conductivity can also be reduced by performing a desalting process using electrodialysis or a dialysis membrane, it is not an appropriate method because it requires labor and cost. On the other hand, when the electrical conductivity exceeds 15 mS / cm, a phenomenon such as precipitation of crystals occurs when the paper coating composition is produced using the paper coating composition material of the present invention. It may inhibit the stability of things. More preferable electric conductivity is 4 to 10 mS / cm.

  In addition, the material for paper coating composition of the present invention is foamed so that the foam density is 0.08 to 0.15 g / ml, and then the amount of foam remaining when left at 25 ° C. for 3 hours. Can be 70% (v / v) or more. The material for paper coating composition of the present invention is excellent in the stability of bubbles. Therefore, by using the paper coating composition material of the present invention as a raw material for the paper coating composition, it is possible to produce a paper that is thick, light, difficult to see through, easily turned, and has a good hand feeling and texture. Can do. More preferably, the remaining amount of the foam is 80% (v / v) or more.

  Here, the bubble density and the remaining amount of bubbles can be measured, for example, by the following method (see FIGS. 6A and 6B). 6 (a) is a front view schematically showing an example of a graduated cylinder containing the material for paper coating composition of the present invention immediately after foaming, and FIG. 6 (b) is a front view of FIG. It is a front view which shows typically an example of the graduated cylinder after leaving the material for paper coating compositions of this invention of a) at 25 degreeC for 3 hours.

  First, a paper coating composition material of the present invention having a predetermined mass [g] is weighed into a ball, and this is stirred with a whipper to foam. Next, immediately after the foamed paper coating composition material of the present invention is transferred to a graduated cylinder, the position (A) on the upper surface of the foamed paper coating composition material of the present invention is set as a scalpel. The volume [ml] of the foamed paper coating composition material of the present invention is measured by reading with a cylinder scale (see FIG. 6A). By dividing the measured mass by the measured volume, the foam density [g / ml] of the foamed material for paper coating composition of the present invention is calculated. Needless to say, the mass may be measured after the foamed material for paper coating composition of the present invention is transferred to a measuring cylinder.

  Next, after the foamed material for paper coating composition of the present invention was allowed to stand at 25 ° C. for 3 hours, the position (B) on the upper surface of the material for paper coating composition of the present invention was placed on the graduated cylinder. Read on the scale (see FIG. 6 (a) and FIG. 6 (b)). Here, when the paper coating composition material of the present invention is separated, a liquid (egg white solution) accumulates in the lower part of the graduated cylinder. In this case, the position (C) of the lower surface of the paper coating composition material of the present invention is read with the scale of the graduated cylinder (see FIG. 6B). Thereby, the residual amount of foam is computable from the following formula | equation (1).

Residual amount of foam [% (v / v)] = {(B) − (C)} / (A) × 100 [% (v / v)] (1)
(A): Position of the upper surface of the foamed paper coating composition material of the present invention (B): Position of the upper surface of the paper coating composition material of the present invention after standing (C): Standing For example, in FIG. 6 (a) and FIG. 6 (b), (A) is the position of the scale of 100 ml, and (B) is the position of the scale of 99 ml. , And (C) are at the position of 1 ml scale, the remaining amount of foam is (99-1) [ml] / 100 [ml] × 100 [%] = 98% (v / v).

  The paper coating composition material of the present invention has a water separation of 7 when allowed to stand at 25 ° C. for 3 hours after foaming so that the foam density is 0.08 to 0.15 g / ml. % (V / v) or less. Here, it can be said that the smaller the water separation amount, the higher the stability of the bubbles. The material for paper coating composition of the present invention is excellent in the stability of bubbles. Therefore, by using the paper coating composition material of the present invention as a raw material for the paper coating composition, it is possible to produce a paper that is thick, light, difficult to see through, easily turned, and has a good hand feeling and texture. Can do. More preferably, the water separation amount is 5% (v / v) or less.

  The bubble density can be measured, for example, by the above-described method (see FIGS. 6A and 6B). Further, the water separation amount can be measured, for example, by a method similar to the method for obtaining the remaining amount of foam described above (see FIGS. 6A and 6B). That is, the water separation amount can be calculated from the following equation (2).

Water separation amount [% (v / v)] = (C) / (A) × 100 [% (v / v)] (2)
(A): Position of the upper surface of the foamed paper coating composition material of the present invention (C): Position of the lower surface of the paper coating composition material of the present invention after standing, for example, FIG. ) And FIG. 6B, when (A) is at the position of the scale of 100 ml and (C) is at the position of the scale of 1 ml, the water separation amount is 1 [ml] / 100 [ml] × 100 [%] = 1% (v / v).

Moreover, the paper coating composition material of the present invention has a residual amount of foam when allowed to stand at 25 ° C. for 3 hours after foaming so that the foam load resistance is 3 to 10 gf / cm ^2. It can be 70% (v / v) or more. The material for paper coating composition of the present invention is excellent in the stability of bubbles, and the bubbles are composed of fine bubbles. Therefore, by using the paper coating composition material of the present invention as a raw material for the paper coating composition, it is possible to produce a paper that is thick, light, difficult to see through, easily turned, and has a good hand feeling and texture. Can do. More preferably, the remaining amount of the foam is 80% (v / v) or more. Here, it can be said that the larger the residual amount of bubbles, the higher the stability of the bubbles.

Furthermore, the material for paper coating composition of the present invention has a water separation amount of 7% when allowed to stand at 25 ° C. for 3 hours after foaming so that the foam load resistance is 3 to 10 gf / cm ^2. (V / v) or less. The material for paper coating composition of the present invention is excellent in the stability of bubbles, and the bubbles are composed of fine bubbles. Therefore, by using the paper coating composition material of the present invention as a raw material for the paper coating composition, it is possible to produce a paper that is thick, light, difficult to see through, easily turned, and has a good hand feeling and texture. Can do. More preferably, the water separation amount is 5% (v / v) or less. Here, it can be said that the smaller the water separation amount, the higher the stability of the bubbles.

The foam density and the water separation amount can be measured by the above-described methods. Moreover, the load resistance of foam can be measured by the following method, for example. First, the paper coating composition material of the present invention is agitated to foam, and then the foamed paper coating composition material surface is flattened and a weight with a bottom area of Ycm ² is applied. When the mass is Xg, the load resistance can be calculated by the following equation (3).
Withstand load (gf / cm ² ) = X (gf) / Y (cm ² ) (3)
In addition, the allergenicity of the material for paper coating composition of the present invention can be reduced. In this case, in the material for paper coating composition of the present invention, the mass of unmodified ovalbumin per solid content is preferably 5 mg / g or less, more preferably 2 mg / g, and 1 mg / g. More preferably. As described above, ovalbumin is one of egg white proteins contained in egg white. Ovalbumin has allergenic properties.

  In general, if allergen is present on the surface of paper, for example, when an infant or an infant licks the paper, it may cause allergic symptoms.

  The material for paper coating composition of the present invention has a reduced content of ovalbumin having allergenicity because the mass of unmodified ovalbumin per solid content is 5 mg / g or less. And the like can prevent the development of allergies when the paper produced using the paper coating composition material of the present invention is licked. For this reason, highly safe paper can be obtained.

The method for measuring the concentration of ovalbumin is not particularly limited. For example, it can be measured by the ELISA method according to “Ministry of Health, Labor and Welfare” “Testing Method for Foods Containing Allergic Substances” (No. 11060001). Although it does not specifically limit as a measurement kit of ovalbumin, For example, Morinaga Bioscience Institute make allergen measurement kit "egg measurement kit (ovalbumin)" (OA kit) can be used.
2. Paper coating composition The paper coating composition of this invention contains the material for paper coating compositions of the said invention, and can further contain a pigment and a binder. Furthermore, the other component mentioned later can be included as needed.

  Examples of the pigment include clay (kaolin clay), talc, silica, calcium carbonate, titanium oxide, satin white, aluminum hydroxide, and other plastic pigments.

  Examples of the binder include a latex binder and a water-soluble binder. Examples of the latex binder include SB (styrene butadiene) latex, acrylic latex, and vinyl acetate latex. Water-soluble binders are mainly classified into natural polymers, semi-synthetic polymers, and synthetic polymers. Examples of the natural polymer include starch (corn starch, wheat starch, tapioca starch, potato starch, sweet potato starch, etc.), mannan, seaweed (funari, agar, sodium alginate, etc.), plant mucilage (Totorooi, tragacanth gum, gum arabic) Etc.), microbial mucilage (dextran, levan, etc.), plant or animal protein (glue, gelatin, casein, collagen, soy protein, etc.). Examples of the semi-synthetic polymer include cellulose polymers (such as viscose, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, and carboxymethyl cellulose) and starch systems (such as soluble starch, carboxymethyl starch, and dialdehyde starch). Examples of the synthetic polymer include polyvinyl alcohol, sodium polyacrylate, polyethylene oxide, and alkali-soluble latex.

  Examples of other components include dispersants, lubricants, preservatives, and water resistance agents. Examples of the dispersant include phosphates (sodium tripolyphosphate, sodium hexametaphosphate, sodium pyrophosphate, etc.), sodium naphthalenesulfonate / formalin condensate, polycarboxylate (sodium polyacrylate, styrene-maleic acid copolymer) Combined sodium, etc.). Examples of the lubricant include sodium stearate, ammonium, sulfonated oil, fatty acid ester, and wax emulsion. Examples of the preservative include organic sulfur compounds, organic halogen compounds, phenol compounds, heterocyclic nitrogen compounds, organic salt esters, and quaternary ammonium compounds. Examples of water-proofing agents include wax emulsions, insoluble fatty acids, soaps, Yuliya or melamine / formalin resins, and glyoxal.

  Next, the present invention will be described more specifically with reference to examples. In addition, unless otherwise indicated,% in an Example has shown that it is the mass%, respectively. Moreover, the following description shows the aspect of this invention generally, and this invention is not limited by this description without a particular reason.

  Hereinafter, the manufacturing method of the material for paper coating compositions of Example 1 is demonstrated. In the present embodiment, experimental results when the other conditions are unified by changing the pH during heating in each experimental example will be described.

[Experimental Example 1]
Thaw 300 g of frozen egg white (manufactured by QP Corporation), put into a stainless steel cup, add 450 g of fresh water to this, add 20% (w / W) The pH of this egg white aqueous solution was adjusted to 9.5 by adding trisodium phosphate aqueous solution. Next, the pH 9.5 egg white aqueous solution was transferred to a constant temperature water bath, and the product temperature reached 85 ° C. while stirring with a marine propeller type stirrer. A material for paper coating composition 1 was obtained.

[Experimental Example 2 to Experimental Example 5]
In Experimental Example 1, the amount of 20% (w / w) trisodium phosphate aqueous solution to be added was changed to adjust the pH of the egg white aqueous solution to 10.0, 10.5, 11.0, and 11.5, respectively. Were the same operations as in Experimental Example 1 to obtain the paper coating composition materials of Experimental Examples 2 to 5. That is, in Experimental Example 2 to Experimental Example 5, heat treatment was performed in a state where the pH of the egg white aqueous solution was 10.0, 10.5, 11.0, and 11.5, respectively.

[Comparative Examples 1-3]
In Experimental Example 1, the pH of the egg white aqueous solution was adjusted to 8.0 by adding 20% (w / w) citric acid aqueous solution instead of 20% (w / w) trisodium phosphate aqueous solution. The material of Comparative Example 1 was obtained by performing the same operation under the same conditions as in Experimental Example 1 except that the .0 egg white aqueous solution was heated.

  In Experimental Example 1, the pH of the egg white aqueous solution was adjusted to 9.0 and 12.0, respectively, by changing the amount of the 20% (w / w) trisodium phosphate aqueous solution to be added (however, the pH was 12.2). When adjusting to 0, after the pH reached 11.0, crystals of trisodium phosphate were added), and the same egg white aqueous solution at pH 9.0, 12.0 was heated. By performing the same operation under the conditions, materials of Comparative Examples 2 and 3 were obtained.

  Table 1 shows the evaluation results of various physical properties measured for the paper coating composition materials obtained in Experimental Examples 1 to 5 and Comparative Examples 1 to 3.

  The adjusted pH and the pH after heating were each measured using a pH meter (METTLER, MI229 type) for each of the paper coating composition materials of each experimental example and the materials of each comparative example. Was measured. Here, “adjusted pH” is a pH at the time of pH adjustment (before heating), and “after-heating pH” is a pH measured by cooling to 25 ° C. after heating at a product temperature of 85 ° C. for 10 minutes.

  The electrical conductivity was measured using the electrical conductivity meter (Yokogawa Electric Co., Ltd., model SC82) for the obtained paper coating composition materials of each experimental example and the materials of each comparative example. Measured at 25 ° C.

  The viscosity was measured for the obtained paper coating composition materials of each experimental example and the materials of each comparative example using a VISCOTESTER VT-303E (manufactured by RION) at a product temperature of 20 ° C.

  The remaining amount of foam and the amount of water separation were measured according to the above-described methods (see FIG. 6A and FIG. 6B), respectively. That is, 20% (w / w) citric acid aqueous solution or 20% (w / w) trisodium phosphate aqueous solution was added to the obtained paper coating composition material and each comparative example material. After adjusting to pH 9.0 at a product temperature of 20 ° C., 150 g is taken on a 5-coated ball of Kitchen Aid Mixer (Kitchen Aid Co., Ltd.) and stirred for 6 minutes at a speed of 6 scales. Then, 100 ml of the obtained foamed composition was transferred to a 100 ml graduated cylinder, the mass was measured, and then the above-described method (see FIGS. 6 (a) and 6 (b)). ) And the remaining amount of foam and the amount of water separation were measured.

  As with the measurement of the remaining amount of foam and the amount of water separation, the load resistance was 20 (w / w) (%) for each of the obtained paper coating composition materials of each experimental example and each comparative material. An aqueous acid solution or a 20% (w / w) trisodium phosphate aqueous solution was added to adjust the pH to 9.0, and foamed so that the foam densities were the values shown in Table 1, respectively. Then, the measurement was performed according to the method described above using a columnar aluminum weight having a diameter of 4 cm.

  In all of the paper coating composition materials of Experimental Examples 1 to 5, the remaining amount of foam was 70% (v / v) or more and the water separation amount was 7% or less. The paper coating composition materials of Experimental Examples 1 to 5 did not aggregate after heating. On the other hand, in the materials of Comparative Examples 1 and 2, aggregation occurred after heating and white turbidity occurred. Moreover, in the material of Comparative Example 3, browning occurred by heating. This is presumably due to the Maillard reaction.

  Next, the manufacturing method of the material for paper coating compositions of Example 2 is demonstrated. In the present embodiment, the experimental results when the heating temperature is changed in each experimental example and other conditions are unified will be described.

[Experimental Example 6]
Thaw 300 g of frozen egg white (manufactured by QP Corporation), put into a stainless steel cup, add 450 g of fresh water to this, add 20% (w / W) The pH of the egg white solution was adjusted to 10.5 by adding an aqueous solution of trisodium phosphate. Next, this egg white aqueous solution with a pH of 10.5 was transferred to a constant temperature water bath, and the product temperature was reached to 75 ° C. while stirring with a marine propeller type stirrer. w / w) A paper coating composition material of Experimental Example 6 was obtained by adjusting the pH to 10 by adding an aqueous citric acid solution.

[Experimental Example 7 to Experimental Example 10]
In Experimental Example 6, the same operation as in Experimental Example 6 was performed except that the temperature of the egg white aqueous solution during heating was 80 ° C., 85 ° C., 90 ° C., and 98 ° C., respectively. -The material for paper coating compositions of Experimental Example 10 was obtained.

[Comparative Examples 4 and 5]
In Experimental Example 6, the paper coating of Comparative Examples 4 and 5 was carried out under the same conditions as in Experimental Example 6 except that the temperature of the egg white aqueous solution at the time of heating was set to 70 ° C. and 100 ° C., respectively. A composition material was obtained.

  Table 2 shows the evaluation results of various physical properties measured for the paper coating composition materials obtained in Experimental Examples 6 to 10 and Comparative Examples 4 and 5. The pH, electrical conductivity, viscosity, foam density, remaining amount of foam, water separation amount, and load resistance were all measured using the apparatus measured in Example 1.

  In all of the paper coating composition materials of Experimental Examples 6 to 10, the remaining amount of foam was 70% (v / v) or more and the water separation amount was 7% or less. In addition, the paper coating composition materials of Experimental Examples 6 to 10 did not aggregate after heating. On the other hand, in the material of Comparative Example 4, the remaining amount of foam was less than 70% (v / v) and the water separation amount exceeded 7% or less, so the stability of the bubbles was poor, and the paper coating of the present invention It is unsuitable as a material for work composition. Moreover, in the material of Comparative Example 5, spillage occurred during heating in the operation process, and an appropriate material could not be obtained. Thereby, the heating condition of 100 ° C. is unsuitable. Further, the material of Comparative Example 5 was browned by heating. This is presumably due to the Maillard reaction.

  Next, the manufacturing method of the material for paper coating compositions of Example 3 is demonstrated. In this example, the experimental results when adding 1.5 times the mass of water to egg white and heating the egg white aqueous solution at the heating temperature, heating time and pH shown in Table 3 will be described.

  In lane 1 of Table 3, an unheated raw egg white aqueous solution having a pH of 9.0 was used. Moreover, in Lane 2 to Lane 9 in Table 3, the same conditions as in Experimental Example 1 of Example 1 described above except that the egg white aqueous solution was heated at the heating temperature, heating time, and pH described respectively. And the composition of Lane 2 to Lane 9 was obtained by performing the same operation.

  Subsequently, the composition of Lane 1 to Lane 9 was analyzed by non-SDS polyacrylamide gel electrophoresis. The band pattern obtained by electrophoresis is shown in FIG.

  The polyacrylamide gel used for the electrophoresis of this example was a gradient gel (manufactured by Tefco, trade name: NON-SDS-PAGEmini) having a gel thickness of 1 mm and a gel concentration of 4-12%. Dilute with sample dilution buffer (0.5M Tris / HCl buffer) without SDS and reducing agent so that the protein concentration in Lane 1 to Lane 9 is 1 mg / ml, and 10 μl of it is subjected to electrophoresis. Using. Electrophoresis was performed at a constant current of 18 mA. Coomassie blue R250 was used for gel staining. The measurement was performed using a digital gel imager (trade name: Ultra Cam, manufactured by Ultra Lamb).

  Moreover, the pixel intensity | strength of each peak of the band obtained by electrophoresis was measured about the composition of each lane of Table 3 using the digital gel imager. For the compositions of Lanes 1 to 9 in Table 3, the pixel intensity of each peak of the band obtained by electrophoresis was measured using a digital gel imager. The measurement results are shown in Tables 4 and 5 and FIGS.

  2 to 5 show pixel intensity distributions of the respective bands in lanes 1, 3, 4, and 9. FIG. In Table 4, the numerical value indicates the peak area obtained from the pixel intensity in each band, and each band No. in each lane 1, 3, 4, 9 is shown. Is the band No. of each lane in FIGS. Corresponding to In Table 4, the italicized values indicate the peak area of OVA1. Furthermore, Table 5 shows the peak area of OVA1 in each lane obtained by measurement with a digital gel imager, and the ratio of the peak area of OVA1 in each lane to the peak area of OVA1 in lane 1.

  2 to 5 show the peak areas of the bands obtained by non-SDS polyacrylamide electrophoresis, measured using a digital gel imager, for the compositions in lanes 1, 3, 4, and 9, respectively. It is shown. More specifically, in the pixel intensity distribution of lane 1 (raw egg white aqueous solution), peak 1 indicates ovotransferrin (OVT), peak 2 indicates ovalbumin 2 (OVA2), and peak 3 indicates ovalbumin 1 (OVA1). (See FIG. 2). In the pixel intensity distribution of the composition in lane 3, peak 1 indicates ovalbumin 2 (OVA2), and peak 2 indicates ovalbumin 1 (OVA1) (see FIG. 3). In the pixel intensity distribution of the composition in lane 4, peak 5 indicates ovalbumin 1 (OVA1) (see FIG. 4). In the pixel intensity distribution of the composition in lane 9, peak 1 indicates ovalbumin 1 (OVA1) (see FIG. 5).

  The composition in lane 4 was obtained by heating an egg white aqueous solution having a pH of 10.5 at a temperature of 80 ° C. for 10 minutes. As shown in Table 4, the peak area of the band indicating ovalbumin 1 (OVA1) of the composition in lane 4 (peak 5 in FIG. 4) indicates ovalbumin 1 (OVA1) in lane 1 (live egg white). It was 8.8% (about 4352 / about 49652 × 100%) of the peak area of the band (peak 4 in FIG. 2).

  On the other hand, the composition of lane 3 was obtained by heating an egg white aqueous solution having a pH of 10.5 at a temperature of 70 ° C. for 30 minutes. As shown in Table 4, the peak area (peak 4 in FIG. 3) showing the ovalbumin 1 (OVA1) of the paper coating composition material in lane 3 is the ovalbumin 1 in lane 1 (live egg white). It was 97.1% (about 48198 / about 49652 × 100%) of the peak area (peak 4 in FIG. 2) showing (OVA1).

  The composition in lane 9 is obtained by heating an egg white aqueous solution having a pH of 9.0 at a temperature of 80 ° C. for 10 minutes. The peak area of the band indicating ovalbumin 1 (OVA1) of the paper coating composition material in lane 9 (peak 1 in FIG. 5) is the peak of the band indicating ovalbumin 1 (OVA1) in lane 1 (live egg white). It was 20.8% (about 10321 / about 49652 × 100%) of the area (peak 4 in FIG. 2).

  Based on the above results, when the pH of the egg white aqueous solution is adjusted to 9.0 or heated, or when the heating temperature is less than 75 ° C., the peak area of the band of ovalbumin 1 (OVA1) is raw egg white having the same protein concentration. It was confirmed that it exceeded 20% of the peak area of the band of ovalbumin 1 (OVA1) in the diluted solution. On the other hand, when the egg white aqueous solution is heated at 80 ° C. or 90 ° C. at pH 10.5, the peak area of the band of ovalbumin 1 (OVA1) is the same as that of ovalbumin 1 (OVA1) in the diluted raw egg white solution having the same protein concentration. It was confirmed that it was 20% or less of the peak area of the band.

  Further, when the egg white aqueous solution was heated at 80 ° C. or 90 ° C. at pH 10.5, the peak area of the band of ovotransferrin (OVT) was hardly detected (see FIG. 1). Therefore, in this case, it was confirmed that the peak area of the band of ovotransferrin (OVT) was 20% or less of the peak area of the band of ovalbumin 1 (OVA1) in the diluted raw egg white solution having the same protein concentration. .

  Next, the manufacturing method of the paper coating composition of Example 4 is demonstrated. In this example, a paper coating composition was produced under the conditions shown below using the paper coating composition material obtained in Example 1 (Experimental Example 1). The formulation of the paper coating composition of Example 4 is shown in Table 6. In Example 4, sodium stearate was used as the lubricant, and an epoxy resin was used as the water resistance agent. The materials shown in Table 6 were set to “high speed rotation” using a Hobart mixer (manufactured by Hobart) and stirred for 6 minutes to prepare a paper coating composition of Example 4. Moreover, the paper coating composition which does not contain the paper coating composition material of Example 1 (Experimental Example 1) was prepared as Comparative Example 6 under the same conditions.

  Moreover, using the compositions of Example 4 and Comparative Example 6, respectively, a coated paper was prepared using a laboratory blade coater (manufactured by Mitsubishi Heavy Industries, Ltd.). A method for measuring physical properties of coated paper is shown below. Table 7 shows the physical property measurement results of the coated paper.

[Measurement method of physical properties of coated paper]
Glossiness: Glossiness meter (GLOSS METER) manufactured by Murakami Color Research Laboratory was measured with specular reflection intensity of 75 ° and 60 °.

  Whiteness: Measured using a colorimetric color difference meter ZE2000 from Nippon Denshoku Industries Co., Ltd.

  As shown in Table 7, the paper obtained by using the paper coating composition containing the material for paper coating composition obtained in Example 1 (the coated paper of Example 4) is as in Example 1. Compared to the paper obtained by using the paper coating composition not containing the obtained paper coating composition material (coating paper of Comparative Example 6), it is light in spite of the same film thickness. (Low density), a bulky paper excellent in gloss was obtained.

  For the coated paper of Example 4 and the coated paper of Comparative Example 6 for 20 adults (aged 20 to 65), male and female (10 males, 10 females), it is easy to see through, touch and turn easily. A survey on the texture was conducted. At that time, no information about the coated paper such as the material of the coated paper was given.

  As a result, all 20 people answered that the coated paper of Example 4 was less transparent than the coated paper of Comparative Example 6. In addition, 19 out of 20 responded that the coated paper of Example 4 was better than the coated paper of Comparative Example 6. In addition, 17 out of 20 responded that the coated paper of Example 4 was easier to turn than the coated paper of Comparative Example 6. In addition, 19 out of 20 responded that the coated paper of Example 4 had a better texture (high quality) than the coated paper of Comparative Example 6.

  By the above, the paper (coated paper of Example 4) obtained using the paper coating composition containing the paper coating composition material obtained in Example 1 is the paper obtained in Example 1. When the paper is produced with the same thickness as the paper obtained by using the paper coating composition not containing the coating composition material (the coated paper of Comparative Example 6), the paper of the present invention The paper obtained using the coating composition was hard to see through, light, excellent in touch and ease of turning, and good in texture.

  In this example, the mass of ovalbumin per solid content was measured for the paper coating composition materials obtained in Example 1 (Experimental Example 3) and Example 2 (Experimental Example 7), respectively.

  First, a small amount of the paper coating composition material obtained in Example 1 (Experimental Example 3) and Example 2 (Experimental Example 7) was collected, and a dry powder (measurement sample) was obtained by freeze-drying. The ovalbumin content of this dry powder (measurement sample) was measured. The measurement is performed using the allergen measurement kit “Egg Measurement Kit (Ovalbumin)” (OA kit) manufactured by Morinaga Bioscience Research Institute Co., Ltd. No.). The measurement method is shown below.

  2 g of the measurement sample was weighed into a cup dedicated to the homogenizer, 38 ml of a sample diluent (20-fold concentrated sample diluent attached to the kit) was added, and stirring was performed using the homogenizer. Next, the pH of the solution was confirmed, and the pH of the solution was adjusted to 6.0 to 8.0 as necessary. Then, protein extraction was performed by repeating the same stirring operation twice. After completion of the extraction operation, the supernatant obtained by centrifugation at a low temperature (4 ° C.) at 3000 × g for 20 minutes was collected and filtered. Next, 950 μl of the sample diluent was added to and mixed with 50 μl of the obtained filtrate, and this mixed solution was used as a measurement solution. A necessary amount of the antibody-immobilized module is set in a frame in advance, and a standard solution prepared for preparing a measurement solution and a calibration curve (freeze-dried standard solution dissolved in 500 μl of purified water is used as a standard stock solution. Each of the standard stock solutions was prepared by sequentially diluting with a prepared specimen diluent, and 100 μl was added per well. The solution was shaken lightly so that each solution spreads uniformly in the well, and a module lid was attached. Thereafter, each solution was discarded, and the washing operation was repeated 6 times using 250 to 300 μl of washing solution per one time. Next, 100 μl of enzyme-labeled antibody solution was added per well, and the mixture was shaken lightly so that it spreads uniformly in the well. After capping, it was allowed to stand at room temperature for 30 minutes. Thereafter, the enzyme-labeled antibody solution was discarded and the washing operation was performed 6 times using a washing solution. Next, 100 μl of enzyme substrate solution was added per well, and after gently shaking to spread uniformly over the well, the plate was allowed to stand at room temperature (25 ° C.) for 10 minutes under light-shielding conditions. Thereafter, 100 μl of a reaction stop solution was added to stop the color reaction. Thereafter, measurement was performed using a microplate reader under conditions of a main wavelength of 450 nm and a sub wavelength of 600 to 650 nm. The concentration of ovalbumin contained in the measurement solution was determined based on a calibration curve created from the measurement values obtained for the standard solution at each concentration. The same experiment was performed in parallel for 3 wells, and the values obtained from each well were averaged. The calibration curve was obtained from a four coefficient logistic analysis. From this calibration curve, the concentration of native ovalbumin in each well was calculated, and by multiplying the obtained value by the dilution factor (400 times), the mass of native ovalbumin per solid content was calculated.

  As a result, in the paper coating composition material of Experimental Example 3, the mass of unmodified ovalbumin per solid content was 3 mg / g or less. In the paper coating composition material of Experimental Example 7, the mass of unmodified ovalbumin per solid content was 0.5 mg / g or less. From the above results, it was confirmed that the content of unmodified ovalbumin was reduced in the paper coating composition materials of Experimental Example 3 and Experimental Example 7. Thereby, it can be understood that the paper coating composition materials of Experimental Example 3 and Experimental Example 7 have reduced allergenicity.

In Example 3, it is a band pattern obtained by non-SDS polyacrylamide electrophoresis, OVT is ovotransferrin, OVA1,2,3 is ovalbumin1,2,3, respectively. In Example 3, the pixel intensity distribution of each band of the band pattern obtained by non-SDS polyacrylamide electrophoresis, measured using a digital gel imager, for the paper coating composition material in lane 1 is shown. FIG. In Example 3, the pixel intensity distribution of each band of the band pattern obtained by non-SDS polyacrylamide electrophoresis, measured using a digital gel imager, for the paper coating composition material in Lane 3 is shown. FIG. In Example 3, the pixel intensity distribution of each band of the band pattern obtained by non-SDS polyacrylamide electrophoresis, measured using a digital gel imager, for the paper coating composition material in lane 4 is shown. FIG. In Example 3, the pixel intensity distribution of each band of the band pattern obtained by non-SDS polyacrylamide electrophoresis, measured using a digital gel imager, for the paper coating composition material in lane 9 is shown. FIG. 6 (a) and 6 (b) are front views schematically showing an example of a method for measuring the foam density, the residual amount of foam, and the water separation amount of the foam of the paper coating composition material of the present invention. is there.

Explanation of symbols

100 Measuring cylinder 110 Bubble of material for paper coating composition of the present invention 120 Egg white aqueous solution generated by water separation 130 Scale

Claims (13)

1-3 times the mass of water of the egg white and the egg white seen including,
In the band pattern obtained by non-SDS polyacrylamide gel electrophoresis, the peak area of the band of ovalbumin 1 in the paper coating composition material obtained by measurement with a digital gel imager is the digital gel imager. For the paper coating composition, which is 20% or less of the peak area of the band of ovalbumin 1 in the diluted raw egg white solution having the same protein concentration obtained by the measurement according to the above and obtained by the measurement by the digital gel imager The paper coating composition , wherein the peak area of the ovotransferrin band in the material is 20% or less of the peak area of the ovotransferrin band in a diluted raw egg white solution having the same protein concentration as measured by a digital gel imager Material for materials. It is obtained by heating an egg white and an egg white aqueous solution containing 1 to 3 times the mass of the egg white water at 75 to 98 ° C. at a pH of 9.5 to 11.5,
After foaming so that the foam density is 0.08 to 0.15 g / ml, the remaining amount of foam when left at 25 ° C. for 3 hours is 70% (v / v) or more. Material for construction composition. It is obtained by heating an egg white and an egg white aqueous solution containing 1 to 3 times the mass of the egg white water at 75 to 98 ° C. at a pH of 9.5 to 11.5,
A paper coating composition in which the amount of water separation is 7% (v / v) or less after standing for 3 hours at 25 ° C. after foaming so that the foam density is 0.08 to 0.15 g / ml Material for materials. In any of claims 1 to 3,
A material for a paper coating composition that is in a foamed state . In any of claims 1 to 4,
A paper coating composition material having a pH of 8-11. In any of claims 1 to 5,
A paper coating composition material having a viscosity of 1 to 100 mPa · s. In any one of Claims 1 thru | or 6 .
A paper coating composition material having an electric conductivity of 4 to 15 mS / cm.   The material for powdery paper coating compositions obtained by drying the paper coating composition material in any one of Claims 1 thru | or 7. In any of claims 1 to 8 ,
Paper coating composition material with reduced allergenicity. In claim 9 ,
A material for a paper coating composition, wherein the mass of unmodified ovalbumin per solid content is 5 mg / g or less. It claims 1 comprises a paper coating composition material according to any one of 10, paper coatings composition. Diluting the egg white with 1 to 3 times the mass of the egg white water to prepare an egg white aqueous solution;
Heating the egg white aqueous solution at 75 to 98 ° C. at pH 9.5 to 11.5;
Foaming the egg white aqueous solution;
The manufacturing method of the material for paper coating compositions containing this. In claim 12 ,
After the heating step, the step of adjusting the egg white aqueous solution to pH 8-11,
A method for producing a material for a paper coating composition.