JP4018086B2 - Gypsum board and manufacturing method thereof - Google Patents

Description

  The present invention relates to a gypsum board having deodorant properties and antibacterial properties and a method for producing the same. More specifically, the present invention relates to a gypsum board that is imparted with deodorizing properties and antibacterial properties without causing curing inhibition by blending tea components, and has reduced deodorizing properties and antibacterial properties due to heat drying, and a method for producing the same.

In recent years, the demand for tea-based beverages has increased due to the increasing consumer-oriented health beverage orientation, and research has been progressing on its active ingredients. Among them, catechin, which is a kind of green tea polyphenol extracted from green tea, has antibacterial properties and other excellent properties, and has been tried to be used in various fields. One of these is gypsum board. Patent Document 1 below describes an antibacterial deodorizing gypsum board containing green tea extracted catechin in either one or both of base paper for gypsum board and gypsum. Patent Document 2 below describes interior building materials such as gypsum board containing green tea leaves and tea components.
JP-A-11-303303 JP 2001-348968 A

  However, when catechin extracted and prepared from green tea is blended with gypsum as in Patent Document 1, curing inhibition tends to occur when the slurry gypsum is formed into a plate material or the like. The reason for this is that catechin is one of the tannins listed as one of the gypsum curing retarders, so that it is likely that curing inhibition is likely to occur as well (reference: “Gypsum” by Michio Sekiya, 218). Page, Gihodo Inc.). In order to prevent this, it is necessary to reduce the amount of green tea extracted catechins to such an extent that curing inhibition does not occur, and satisfactory antibacterial and deodorant functions cannot be imparted to the gypsum board. Therefore, this method does not provide a product that meets market needs, and is not suitable for an actual production line for gypsum board production.

  On the other hand, when the green tea leaf of Patent Document 2 is used, the organic fiber of the tea leaf is blended as it is, which adversely affects the flame resistance characteristic of the gypsum board. Further, when tea leaves that are solid particles are used, the dispersibility is poor and the components are unevenly distributed, so that the antibacterial and deodorizing functions are not efficiently exhibited on the board surface. Furthermore, tea leaf-derived spots appear on the gypsum board base paper, and the product value also decreases. In order to improve these, it is conceivable to blend into gypsum after fine pulverization in order to enhance the dispersibility of the dried green tea leaves, but the cost and labor of the pulverization process become problems. In addition, since the dried green tea pulverized product absorbs moisture and expands, it is difficult to control the pulverization of the dried green tea product so that it becomes tea leaves of the desired particle size in the gypsum board and eliminate the influence on the flame resistance. is there.

  As described above, the method of blending green tea extracted catechins and tea leaves into gypsum cannot fully utilize the functions of the active ingredients of green tea, causing the gypsum to inhibit curing and decrease the flame resistance, so the curing time is stable, There has been no known method for producing a gypsum board capable of obtaining an antibacterial and deodorant gypsum board having flame resistance.

  An object of the present invention is to provide a gypsum board in which an active ingredient of tea is blended in a gypsum board, and exhibits suitable antibacterial and deodorizing properties and has flame resistance in a stable curing time.

  Also, the present invention provides a method for producing a gypsum board capable of providing a gypsum board that contains a tea active ingredient and exhibits suitable antibacterial and deodorant properties and retains flame resistance at a low cost and with a stable curing time. It is an issue to provide.

  In addition, the present invention contributes to the effective use of manufacturing residues of tea-based beverages and can reduce the burden on the global environment in providing a gypsum board that has antibacterial and deodorant properties and retains flame resistance. It is an object to provide a method for producing a gypsum board.

  In order to solve the above problems, in the present invention, a method for protecting the active ingredient of tea in gypsum without affecting the flame resistance of gypsum was developed, and the active ingredient of tea was used without inhibiting the hardening of gypsum. We have provided a gypsum board that can fully utilize antibacterial and deodorant functions.

  According to one aspect of the present invention, a gypsum board manufacturing method is prepared by preparing a gypsum slurry containing a hydrated tea leaf pressing liquid, molding the gypsum slurry into a board shape, and curing and drying.

Moreover, according to the other aspect of this invention, the manufacturing method of the gypsum board prepared the aqueous liquid containing the tea-leaf particle | grains containing the polyphenol derived from tea and having a particle size of 7-360 micrometers, and mix | blended the said aqueous liquid. The gist is to prepare a gypsum slurry, shape the gypsum slurry into a board shape, and cure and dry the gypsum slurry.

Further, according to another aspect of the present invention, a method for producing a gypsum board includes impregnating a water-absorbing mineral with a water-containing tea pressing solution to protect the polyphenol derived from tea leaves with the mineral, and blending the mineral The gist of the present invention is to prepare a gypsum slurry, which is molded into a board shape, cured and dried.

  The gypsum board of this invention is manufactured according to said manufacturing method.

Further, according to one aspect of the present invention, gypsum boards, plaster and particle size contain polyphenols from tea is squeezed liquid impregnation of an aqueous solution or water-containing tea leaves containing tea leaves particles is 7~360μm the The gist of the present invention is to contain a polyphenol derived from tea leaves and a mineral having a granular water-absorbing property that protects the gypsum from the gypsum.

  A gypsum board that has antibacterial and deodorant properties is formulated by blending the active ingredients of tea without causing curing inhibition, and a gypsum board that maintains flame resistance and exhibits suitable antibacterial and deodorant properties Provided. In providing gypsum board, it contributes to the effective use of tea-based beverage manufacturing residues and the reduction of the burden on the global environment.

  Catechin contained in green tea has antibacterial and deodorizing properties, and can be imparted with antibacterial and deodorizing properties by blending catechins to produce products. Deodorant components are present not only in catechins but also in other green tea components. Oolong tea and coffee also contain deodorant components.

  In order to impart antibacterial and deodorant properties to the gypsum board, when the above-mentioned green tea active ingredients are blended into the gypsum slurry, gypsum curing inhibition occurs. This is because catechin, a kind of tannin (curing inhibitor), acts on gypsum. In addition, the antibacterial and deodorizing functions of the active ingredient are reduced by heating and drying the gypsum board, which is considered to be due to the effect of the heat received by the active ingredient. When blending other types of tea components such as oolong tea to impart deodorant properties, the tannin contained in the tea similarly inhibits curing and lowers the function during heat drying. Therefore, in order to prevent these, a means for protecting the active ingredient in gypsum is required. When the tea leaves themselves are blended with gypsum, the tea leaves containing the active ingredient serve as a protective means, but since the tea leaves are large organic fibers, the flame resistance of the gypsum is impaired.

  Therefore, as a result of searching for a protection method that does not impair the flame resistance of gypsum, it was found that it is effective to physically protect the active ingredient with a mineral having water absorption as the first method. That is, by introducing the active ingredient into the water-absorbing mineral and blending it into gypsum, the active ingredient is protected by the water-absorbing mineral, and the action with gypsum and the outflow during drying are suppressed. Since the protective means is mineral, the flame resistance of gypsum is not impaired.

  In addition, as a result of examining the form of blending the active ingredient of green tea into gypsum, as a second method of protecting the active ingredient, the concentration of total polyphenols is not increased by extraction and purification such as catechin preparations. It has been found that it is effective to use a coexisting component. Specifically, when a pressing liquid obtained by pressing water-containing tea leaves and extruding the components in the tea leaves is used, inhibition of gypsum curing is suitably prevented, and the active ingredients of green tea function extremely efficiently. In particular, a squeezed solution obtained by squeezing a hydrated tea leaf residue that is an extraction residue after extracting a tea beverage is effective.

  As a mechanism for protecting the active ingredient of green tea in the second method using the compressed liquid, first, the active ingredient contained in the liquid is dispersed in the form of relatively larger particles than the catechin preparation, and gypsum and tannin Therefore, the ratio of the function being impaired due to the action with gypsum and the influence from the outside may be reduced. The catechin preparation purified from the green tea extract disperses in water when dissolved in water, but in addition to the polyphenols containing catechin, various other extractive components coexist in the squeezed liquid, and very fine by pressing. Tea leaf particles are released from the tea leaf residue. These constitute particles having a particle size of about 7 to 360 μm (they are mostly around 45 μm).

  As a second mechanism, polyphenols present in tea leaf particles are protected from physical action by fine tea leaf particles, and are protected physicochemically.

  Therefore, if it mix | blends with gypsum according to a 2nd method, the ratio with which antibacterial property and deodorant property remain will increase. Moreover, since the extract (1st decoction) for drink manufacture has a high tannin content rate in an extract, the ratio which acts with gypsum also becomes high and it is easy to raise | generate hardening inhibition. Therefore, the ratio of the active ingredient and the fat-soluble ingredient and the like, and the size of the dispersed particles are much more effective than the tea leaf extract, the pressed liquid obtained by pressing the extracted tea residue, It is also economical and environmentally advantageous. In order that the active ingredient blended in the gypsum board in the second method exhibits its function well and the inhibition of curing is suitably suppressed, in the particles containing the active ingredient in the liquid, the particle size is 7 to 360 μm. There must be.

  In this way, it is possible to produce antibacterial and deodorant gypsum board at low cost by using the pressed liquid of tea husk, which is a beverage extraction residue, and to effectively use the hydrated tea leaf residue that is discharged in large quantities from beverage factories and the like every year. Can contribute to promotion. Since the water-containing tea leaf residue can be spoiled or deteriorated, it needs to be treated properly, and in order to reduce the burden on the processing equipment that treats the residue with a very high moisture content, The residue is pressed and dehydrated. This dehydrated waste liquid requires a large treatment plant for waste liquid treatment, and it costs a lot of money, so it becomes a burden of processing and effective use of organic waste, but by using the dehydrated waste liquid as a raw material for producing gypsum board Thus, it is not necessary to perform such waste liquid treatment, and a gypsum board having a function added by utilizing the active ingredients remaining in the tea leaf residue can be provided.

  Beverage production waste liquids that require waste liquid treatment include narrow-sense teas such as black tea and oolong tea (tea made from tea tree), and dehydrated waste liquids (ie, residue pressing liquids) in the production of coffee, grain tea, and the like. Since these dehydrating waste liquids contain polyphenols and deodorizing functional components, they can be used in the same manner as a raw material for producing a deodorizing gypsum board. Also, other beverage manufacturing waste liquids contain fine particles of fat-soluble components, even if they do not contain functional components such as deodorant and antibacterial, so they are used by mixing the dehydrated waste liquids of other beverages with the dehydrated waste liquid of green tea May be. Alternatively, catechin may be added to the dehydrated waste liquid and used for the production of antibacterial / deodorant gypsum board. Moreover, you may add the waste liquid containing polyphenols, such as a line washing water produced in a rough tea manufacturing process.

  Below, the manufacturing method of the antibacterial and deodorant gypsum board based on the said 1st and 2nd method is each demonstrated.

  Basic gypsum board is mixed with calcined gypsum and water with additives such as adhesion reinforcing agent, curing regulator, specific gravity regulator, etc., if necessary, and the resulting gypsum slurry is mixed between two board base papers. It is produced by pouring into a plate having a desired thickness, and after the hydration of gypsum is finished, it is dried by hot air to remove residual moisture. Examples of additives include an adhesive reinforcing agent such as starch-based adhesive reinforcing agent, and a specific gravity adjusting agent such as a surfactant (an ethylene oxide adduct of a higher alcohol, an alkali metal salt of an ethylene oxide adduct of a higher alcohol, a polyoxyethylene alkyl ether sulfone). Acid salt, etc.), curing modifiers are curing accelerators (inorganic acid salts such as sodium sulfate, potassium sulfate, sodium chloride, fine powder dihydrate gypsum) and setting retarders (gelatin, glue, gum arabic, colloids such as decomposed keratin, etc.) High molecular weight substances, carboxylates, hexametaphosphates, ethylenediaminetetraacetates, borates, alkaline carbonates, sulfates, sucrose, and other low molecular weight substances). In order to produce an antibacterial / deodorant gypsum board, a gypsum slurry containing an active ingredient of green tea is prepared, and this is used to form and dry in the same manner as a basic gypsum board. A method for preparing a gypsum slurry containing an active ingredient based on the first or second method will be described below. The term “tea leaf” means a tea tree structure containing the above active ingredient, and may be a portion other than “leaf”, and does not exclude stem tea, stick tea, and the like.

  According to the first method, the water-absorbing mineral is impregnated with the active ingredient by bringing the water-absorbing mineral into contact with the water-absorbing mineral and impregnated with the water-absorbing mineral, and this is mixed with a raw material such as calcined gypsum. To prepare a gypsum slurry. Since the active ingredient is protected by the water-absorbing mineral in the gypsum slurry, the aqueous liquid containing the green tea active ingredient can be used in any way, and it can be used as an aqueous solution of catechin preparation, hot water extraction of green tea leaves. Either liquid or green tea residue pressing liquid may be used. The line washing water generated in the crude tea production process also contains green tea polyphenol and can be used well. In addition, a water-absorbing mineral may be impregnated with an aqueous liquid reconstituted from a concentrated liquid or dried product such as green tea extract or green tea residue pressing liquid, and other teas may be used as long as the aqueous liquid contains an active ingredient of green tea. What used the washing water and the dehydration waste liquid in drink manufacture may be used.

  The water-absorbing mineral used according to the first method is preferably a mineral having a water absorption capacity of about 200 to 1300 g / 100 g, for example, a porous mineral having fine pores such as ore foam such as pearlite or diatomaceous earth, Examples include fibrous minerals made by processing slag such as rock wool into cotton. You may use combining the said multiple types of said mineral. The water-absorbing mineral is prepared in a granular or powder form and used for impregnation with an active ingredient of green tea. When the particle size of the mineral exceeds 850 μm, solid-liquid separation is likely to occur when impregnated with an active ingredient of green tea, and the slurry does not become a slurry, so the amount of gypsum board cannot be accurately controlled. Therefore, it is preferable to adjust the particle size so as to be 850 μm or less. Further, the production of mineral particles having a particle size of less than 7 μm causes a problem in the cost of pulverizing the mineral, but such fine pulverization is not necessary, and particles having a particle size in the range of 7 to 850 μm are practically suitable.

  According to the second method, the gypsum slurry is obtained by using an aqueous green tea pressing liquid (a) or an aqueous liquid (b) of an active ingredient of green tea in a particle dispersion state substantially equivalent to the above-described gypsum board raw material. Prepare by mixing. Specifically, particles containing active ingredients are dispersed in an aqueous liquid, and the particle size distribution is about 7 to 360 μm, preferably about 10 to 350 μm. When the particle size of the dispersed particles exceeds 360 μm, the flame resistance of the gypsum board is affected, and when it is less than 7 μm, the antibacterial / deodorizing function cannot be satisfactorily added. The proportion of catechin contained in the gypsum slurry is 0.003 to 0.1 parts by mass with respect to 100 parts by mass of calcined gypsum, and the proportion of total polyphenol is 0.004 to 0.15% by mass with respect to 100 parts by mass of calcined gypsum. Desirably, when the proportion of catechin exceeds 0.1% by mass, curing inhibition tends to occur. Green tea pressing liquid (a) is obtained by pressing water-containing green tea leaves with a compression dehydrator such as a screw press machine, filter press machine, stirring dehydrator, etc. Although the tea husk etc. which are residues may be used, it is preferable to use the tea waste liquid produced by pressing the hydrated tea residue after extraction in terms of suppression of curing inhibition and effective use of resources. The pressurizing pressure at the time of pressing is effective at 0.1 MPa or more, and if it exceeds 5 MPa, the load on the apparatus becomes a problem, so about 0.1 to 5 MPa is preferable. The line washing water discharged in the crude tea production process can also be used because it contains the green tea polyphenol in the above preferred form. You may use the pressing liquid of extraction residues, such as oolong tea, black tea, and coffee, in addition to green tea pressing liquid. The aqueous liquid (b) equivalent to the green tea pressing liquid (a) can be appropriately prepared by combining, for example, an extraction residue pressing liquid or fat-soluble component other than green tea and a catechin preparation or a green tea extract.

  Regarding the blending ratio of each raw material in the gypsum slurry to be molded into gypsum board, the blending amount of the aqueous liquid containing the green tea active ingredient is so that the antibacterial or deodorizing function is properly imparted to the gypsum board. Adjust considering the active ingredient concentration. Specifically, in order to produce an antibacterial / deodorant gypsum board, the total amount of catechins (EGC, EGCg, EC, ECg) is 0.003 parts by mass or more, preferably 0.005 with respect to 100 parts by mass of calcined gypsum. The blending amount of the aqueous liquid is determined so that the total amount of polyphenols is 0.004 parts by mass or more. For example, when using the green tea residue pressing liquid whose solid content is about 1.9% by mass and the total amount of catechin in the solids is about 2.3% by mass, the pressing solution is 12 to 48% by mass with respect to 100 parts by mass of calcined gypsum. By adding about 1 part, the amount of catechin is about 0.005 to 0.02 parts by mass. If the concentration of the active ingredient of green tea in the aqueous liquid is excessively low, a large amount of aqueous liquid is required, and there is a problem of increased cost and reduced efficiency related to transportation from the tea leaf pressing process to the gypsum board manufacturing process. It is preferable to secure an active ingredient concentration such that the aqueous liquid added to mass parts is about 48 mass parts or less. In the case of the first method, the water-absorbing mineral is preferably adjusted to 0.8 to 7.0 parts by mass with respect to 100 parts by mass of calcined gypsum, and less than 0.8 parts by mass, Since the protection of the active ingredient of green tea is not sufficient, the antibacterial / deodorizing function cannot be satisfactorily exhibited, and if it exceeds 7.0 parts by mass, an increase in cost becomes a problem. If the active ingredient is appropriately protected by the water-absorbing mineral, the effect of inhibiting the inhibition of curing is also high, so the upper limit of the catechin content relative to 100 parts by mass of calcined gypsum rises to about 0.13 parts by mass. In addition, since the shaping | molding will become difficult when the water content in a gypsum slurry is excess or insufficient, it is desirable to adjust suitably so that it may become 60-90 mass parts with respect to 100 mass parts of calcined gypsum. It is preferable that additives, such as an adhesion | attachment reinforcement agent, a hardening regulator, and a specific gravity regulator, shall be 1 mass part or less with respect to 100 mass parts of calcined gypsum.

  A gypsum board having antibacterial or deodorizing properties by a green tea component can be obtained by pouring the gypsum slurry prepared according to the above into board base paper, forming it into a plate shape, and drying by heating using hot air. The temperature of the hot air is preferably about 80 to 280 ° C., and the stability of the product is enhanced by continuing to dry gently. Curing in molding preferably proceeds according to the first or second method, and an antibacterial / deodorant gypsum board is produced in a stable molding time, and the flame resistance of the gypsum board is maintained.

  The above manufacturing method relates to antibacterial and deodorant boards, but if other types of tea such as oolong tea and black tea are used instead of green tea, a gypsum board to which deodorizing property is imparted by tea-derived polyphenols is obtained. It is done.

  Hereinafter, the present invention will be described in detail with reference to examples. The present invention is not limited by the following examples.

  The gypsum board raw material shown below was prepared, and the gypsum slurry was prepared according to the blending ratio in Table 2 and the gypsum slurry preparation method described below to produce the gypsum board and to measure the setting time of the gypsum slurry. The state of the base paper surface of the obtained gypsum board was observed, and evaluation of flame resistance, component dispersibility, antibacterial properties and deodorizing properties was performed as follows. Table 3 shows the evaluation results of the state of the base paper surface, the curing time, the flame resistance, the component dispersibility, the antibacterial property and the deodorizing property of each gypsum board. In the following, the average particle size and particle size distribution of the dispersed particles and mineral particles in the squeezed solution and catechin solution were measured by a laser diffraction particle size distribution measuring device.

[Preparation of raw materials]
(Catechin solution)
Hot water was added to the green tea leaves to extract the green tea beverage, and the components contained in the green tea beverage were purified by solvent extraction and column separation to obtain catechin dried products having the total polyphenol content and catechin content shown in Table 1. This dried catechin was dissolved in water for preparing gypsum slurry according to the blending ratio shown in Table 2 to prepare a catechin solution. This catechin solution was used for the production of gypsum boards B1 to B5. In addition, the average particle diameter of the dispersed particles in the catechin liquid was 2.0 μm, and the particle size distribution was 0.2 to 6.7 μm.

(Pressed liquid)
The tea husk (water content 85 mass%), which is the extraction residue after extraction of the green tea beverage, was squeezed with a filter press to dehydrate the tea husk and obtain a squeezed liquid. This compressed liquid was used for manufacture of gypsum board A1-A8. The solid content of the compressed solution was 1.9% by mass. When the total polyphenol content and catechin content in the solid content were examined, the results shown in Table 1 were obtained. Moreover, the average particle diameter of the dispersed particles in the compressed liquid was 44.5 μm, and the particle size distribution was 10.2 to 352 μm.

(Crushed tea leaves)
The dried green tea leaves for producing green tea beverage were crushed and sieved to prepare crushed tea leaves having a particle size of 500 μm to. The ground tea leaves were used for the production of gypsum boards C1 to C4. The total polyphenol content and catechin content of the dried green tea leaves were as shown in Table 1.

(Water-absorbing mineral)
As the water-absorbing mineral, pearlite, which is foamed ore, was finely pulverized to prepare powdery pearlite (water supply capacity: 1300 g / 100 g). The average particle size was 44.5 μm, and the particle size distribution was 10.2 to 850 μm.

[Preparation of gypsum slurry]
(Gypsum boards A1-A3 and B1-B2)
According to the mixing ratio of Table 2, after adding a water-absorbing mineral to catechin liquid or compressed liquid, stirring for 1 hour and mixing in a slurry state, kneaded gypsum, additives and water are added and kneaded to produce gypsum board A gypsum slurry was prepared.

(Gypsum board A4-A8, B3-B5, C1-C4)
A gypsum slurry for gypsum board production was prepared by adding calcined gypsum, an additive and water to a catechin liquid or a compressed liquid or crushed tea leaves according to the blending ratio in Table 2, and kneading them.

[Manufacture of gypsum board]
The gypsum slurry prepared above was poured between two board base papers, the gypsum slurry was formed into a plate shape having a thickness of 12.5 mm, and allowed to stand to advance hydration and curing of the gypsum. Judgment completion time is judged based on the temperature change of the gypsum slurry, 150 ℃ hot air is supplied to the gypsum board after curing and dried for 15 minutes, and then gently dried until it reaches a constant weight in a 40 ℃ atmosphere. It was.

[Measurement of curing time]
The temperature of the molded gypsum slurry was measured, the time when the temperature reached the maximum temperature based on the temperature change was regarded as the end of curing, and the time required for the completion of curing was defined as the curing time of the gypsum slurry. In addition, the hardening time of the gypsum slurry which does not mix | blend a green tea component is 26 minutes, and the range to the hardening time less than 70 minutes is a hardening delay acceptable practically.

[Base paper surface condition]
The state of the base paper surface of the gypsum board was visually observed to confirm the presence or absence of stains. Further, an aqueous solution containing iron ions was sprayed on the surface of the base paper, and it was confirmed whether or not the stains contained polyphenol by utilizing the black change due to the reaction between polyphenol and iron ions. From the observation results, those without stain were considered good, and those with stain and blackened by iron ions were judged as poor.

[Flame resistance]
The heat generation rate (total heat generation amount) per unit area of gypsum board was measured according to the exothermic test described in the evaluation work method document in the designated evaluation organization stipulated in the Building Standards Act. With respect to the flame resistance, the total calorific value is used as an evaluation criterion, and those having a total calorific value in 20 minutes of 8 MJ / m ² or less are evaluated as good, and those exceeding 8 MJ / m ² are evaluated as defective.

[Component dispersibility]
Immerse the gypsum board in an aqueous solution containing iron ions, observe the discoloration of the gypsum board, evaluate the dispersibility of the ingredients using the black change caused by the reaction of polyphenol and iron ions, and the whole changed uniformly to black Good ones, black changes partially and non-uniform ones were bad, and no black change was seen unreacted. In addition, it was confirmed that the gypsum board containing no green tea component was unreacted.

[Antimicrobial]
A 5cm x 5cm sample is cut out from the plasterboard, taken out after being immersed in 1/500 ordinary broth, and the bacteria on the sample (MRSA: methicillin-resistant Staphylococcus aureus) live bacteria according to the film adhesion method established by the Antibacterial Products Technical Council The number (CFU / sheet) was measured, and the antibacterial property was evaluated by viable cell count after 24 hours. In the case of gypsum board containing no green tea component, the viable cell count at 0 hours (immediately after immersion) was 1.6 × 10 ⁵ , and the viable cell count after 24 hours was 8.1 × 10 ^4. The antibacterial property of the sample whose viable count after 24 hours is less than 1 × 10 ⁴ is good, and the sample having 1 × 10 ⁴ or more can be evaluated as bad.

[Deodorization]
A 20 mm × 20 mm sample was cut out from the gypsum board, packed in a Tedlar bag with 3 L of atmospheric gas containing ammonia (initial concentration: 200 ppm) and formaldehyde (initial concentration: 30 ppm) as malodorous substances, and allowed to stand at 37 ° C. for 2 hours. The residual concentration of each malodorous substance in the atmospheric gas in the bag was measured using a gas detection tube manufactured by Gastec Co., Ltd., and the deodorization rate was calculated from the initial concentration and residual concentration of each malodorous substance according to the following formula. The deodorization rate in the gypsum board not containing the green tea component was 46.7% for ammonia and 83.4% for formaldehyde. Therefore, with these as deodorant standards, 51.7% or more for ammonia ( (Standard + 5% or more) is good, less than 51.7% is bad, and for formaldehyde, 88.4% or more (standard + 5% or more) is good, and less than 88.4% is bad.

Deodorization rate (%) = 100 × (initial concentration−residual concentration) / initial concentration

In the above measurement, the gypsum board B5 was not cured, and the gypsum board B4 was unsuitable for actual production because of a long curing time, and other measurements were not performed. Moreover, about the gypsum board C3 and C4, since hardening time and flame resistance were unbearable practically, other measurements were not performed.

  Gypsum board A6 blended with pressing liquid and gypsum board B3 blended with catechin liquid are similar in total polyphenol and catechin, but gypsum board A6 shows good antibacterial and deodorant properties, while gypsum board B3 has low antibacterial and deodorant properties. This is because the green tea component in the catechin liquid is finer than that in the compressed liquid, and therefore the ratio of function loss due to action with gypsum, thermal decomposition during drying, and the like is high. When the amount of catechin liquid is increased in order to obtain the desired antibacterial and deodorant properties, curing inhibition occurs like gypsum boards B4 and B5. However, when the green tea component is protected with a water-absorbing mineral such as gypsum board B1, the antibacterial property of the same level as that obtained when the squeezed liquid is used is exhibited, and the deodorization rate against formaldehyde is also improved. Moreover, it becomes possible to increase the compounding quantity of a green tea component like gypsum board B2.

  On the other hand, in the case of gypsum boards C1 to C4 using ground tea leaves, the inhibition of curing can be suppressed, but the antibacterial properties and deodorant properties are not exhibited satisfactorily, and the flame resistance deteriorates rapidly when the blending amount is increased. In addition, the component dispersibility is poor, and the reaction of polyphenol with iron ions occurs unevenly only in the tea leaf part, and stains due to leakage from the tea leaf also occur on the board base paper.

  When it sees about the gypsum board A4-A8 using a pressing liquid, antibacterial property and deodorizing property will improve as the compounding quantity of a green tea component increases. That is, the function imparted to the gypsum board can be adjusted by the blending amount. However, the inhibition of curing is not completely suppressed, and when the blending amount is increased from A8, the curing time gradually becomes longer, and the upper limit of the blending amount of total polyphenol and catechin when using the compressed liquid is 100 parts by weight of calcined gypsum. The total polyphenol is about 0.15 parts by mass and the catechin is about 0.1 parts by mass.

  When a water-absorbing mineral is used, a gypsum board (for example, A2 and B1) containing the same total polyphenol and catechin using a compressed solution or a catechin solution is as large as when a water-absorbing mineral is not used. There is no difference, and both exhibit good antibacterial and deodorant properties. However, the action of the green tea component tends to be exerted somewhat strongly as a whole when the compressed liquid is used. Regarding suppression of curing inhibition, it is clear from the difference in curing time between the gypsum boards B2 and B4 that the upper limit of the green tea component is significantly higher than when the water-absorbing mineral is not used, Considering the results of B2 and the numerical trends of the gypsum boards A4 to A8, and determining the upper limit of the total amount of polyphenol and catechin when combined with the water-absorbing mineral and the compressed liquid, Polyphenols can be increased to about 0.2 parts by mass and catechins can be increased to about 0.13 parts by mass, and antibacterial and deodorant properties can be further improved while inhibiting curing inhibition and deterioration of flame resistance. More antibacterial and deodorant properties can be provided.

In addition, when diatomaceous earth (particle size: 7.0 to 75 μm) is used as the water-absorbing mineral instead of the pearlite, the same results as in the case of pearlite are obtained.

(Table 2) Gypsum board formulation
Gypsum raw material content [parts by mass]
Board Calcined gypsum Pressed liquid Catechin Grinding Water-absorbing mineral
(Solid content) Dried material Tea leaves
A1 100 12 (0.23) − − 1.5
A2 100 18 (0.34) − − 2.3
A3 100 6.0 (0.11)--0.75
A4 100 6.0 (0.11)---
A5 100 12 (0.23)---
A6 100 18 (0.34)---
A7 100 36 (0.68)---
A8 100 48 (0.91)---
B1 100-0.035-2.0
B2 100-0.35-2.0
B3 100-0.035--
B4 100-0.35--
B5 100-3.5--
C1 100 − − 1.3 −
C2 100 − − 2.5 −
C3 100 − − 3.8 −
C4 100 − − 7.5 −

(Table 3) Measurement results
Plaster Curing time Flame resistance Ingredients Base paper Antibacterial deodorant [%]
Board [min] [MJ / m ² ] Dispersibility Surface [Viable count] NH ₃ HCHO
A1 29 4.6 Good Good 2.4 × 10 ³ 53.0 89.9
A2 34 5.2 Good Good Good 8.3 × 10 ² 53.6 89.9
A3 30 5.2 Unreacted Good 2.8 × 10 ⁴ 51.3 87.8
A4 30 4.1 Unreacted Good 3.1 × 10 ⁴ 51.9 88.2
A5 31 3.5 Good Good 6.1 × 10 ³ 52.6 89.3
A6 34 6.4 Good Good 1.3 × 10 ³ 52.2 90.4
A7 50 3.2 Good Good <10 57.1 92.0
A8 56 4.5 Good Good <10 60.1 93.2
B1 31 4.3 Good Good 1.6 × 10 ³ 47.4 88.8
B2 63 2.9 Good Good <10 47.1 89.6
B3 30 3.7 Unreacted Good 3.1 × 10 ⁴ 47.4 87.6
B4 90 − − − − − −
B5 Not cured------
C1 35 4.2 Defect Defect 1.6 × 10 ⁴ 50.0 87.2
C2 38 5.9 Defect Defect 8.3 × 10 ² 51.3 87.7
C3 42 8.5-----
C4 85 11.5-----
No compound 26 3.1 Unreacted Good 8.1 × 10 ⁴ 46.7 83.4

Claims (14)

  A method for producing a gypsum board, comprising preparing a gypsum slurry containing a pressing solution of hydrous tea leaves, molding the gypsum slurry into a board shape, and curing and drying the gypsum slurry.   The said water-containing tea leaf is a tea leaf residue after extracting tea from a raw tea leaf, The said pressing liquid is a manufacturing method of Claim 1 containing the polyphenol derived from tea.   An aqueous liquid containing tea leaf particles containing polyphenol derived from tea and having a particle size of 7 to 360 μm is prepared, a gypsum slurry containing the aqueous liquid is prepared, and the gypsum slurry is molded into a board shape and cured and dried. A method for producing a gypsum board, comprising:   The solid content of the said pressing liquid or aqueous liquid is a manufacturing method in any one of Claims 1-3 containing a fat-soluble component and polyphenol derived from tea.   The manufacturing method according to claim 4, wherein the fat-soluble component contains carotene or vitamin E.   The said gypsum slurry is a manufacturing method in any one of Claims 1-5 which contains green tea polyphenol in the ratio of 0.004-0.15 mass part with respect to 100 mass parts of gypsum. Water-absorbing minerals are impregnated with water-containing tea leaf pressing solution to protect the polyphenols derived from the tea leaves with the minerals, prepare a gypsum slurry containing the minerals, and form and cure the gypsum slurry into a board shape. A method for producing a gypsum board characterized by drying.   The water-absorbing mineral is an ore foam, a porous mineral, or a fiber mineral, has a water absorption capacity of 200 to 1300 g / 100 g, and has a particle size of 7 to 850 μm. The manufacturing method of Claim 7 mix | blended in the ratio of 0.8-7.0 mass parts with respect to 100 mass parts of gypsum of a slurry. The manufacturing method according to any one of claims 3 to 6 , wherein the aqueous liquid is a pressing liquid obtained by pressing a tea leaf residue after extracting beverage tea from raw tea leaves.   The manufacturing method according to claim 7, wherein the tea is green tea.   The gypsum board manufactured by the manufacturing method in any one of Claims 1-10. Granular water absorption that protects the tea-derived polyphenol from the gypsum by being impregnated with gypsum and an aqueous liquid containing tea-derived particles containing tea-derived polyphenol and having a particle size of 7 to 360 μm or a pressed tea-containing liquid. A gypsum board characterized by containing a mineral. The water-absorbing mineral has a particle size of 7 to 850 μm and a water absorption capacity of 200 to 1300 g / 100 g, and the water-absorbing mineral is 0.8 to 7% with respect to 100 parts by mass of the gypsum. The gypsum board of Claim 12 contained in the ratio of 0 mass part.   The gypsum board according to any one of claims 11 to 13, which contains catechin and has antibacterial and deodorant properties.