JP4021455B2 - Wood board manufacturing method - Google Patents

Description

  The present invention relates to a method for manufacturing a wooden board.

In recent years, along with the health boom, techniques for blending tea, tea extract, etc. into building materials, filters, etc. have attracted attention.
For example, Patent Document 1 proposes a method of manufacturing a wooden board having antibacterial properties by blending tea husks in the wooden board manufacturing process. However, considering costs such as fares, it is necessary to search for a tea-based beverage factory that exists in the vicinity of the wooden board factory in order to obtain tea leaves. Even if there is a tea-based beverage factory in the vicinity of the wooden board factory, capital investment is required to adjust the production schedules of both factories and to acquire a single variety of tea-based beverage residues.

  In patent document 2, the method of manufacturing the interior building material which has the adsorption | suction capability of a hazardous | toxic chemical substance is proposed by mix | blending a tea leaf or a tea leaf containing component with an interior building material. If this method is applied, in the wood board manufacturing process, after adding green tea polyphenol, which is a tea leaf-containing component, to the wood fiber, a wood mat is obtained by forming, the wood mat is dried, and an antibacterial or antibacterial material containing green tea polyphenol is dried. Although a method for producing an odorous wood board is conceivable, when a wood fiber slurry is formed to obtain a wood mat, a large amount of water escapes, so that the green tea polyphenol is detached simultaneously with the forming. In addition, green tea polyphenol is easily decomposed by the drying temperature. Furthermore, when adding tea leaves instead of green tea polyphenols, there is no detailed description of the amount of tea leaves added and examples of effects in Patent Document 2, so when adding tea leaves with reference to the amount of tea shells described in Patent Document 1, The added dry weight of tea leaves is about 1 to 5 kg for an insulation board of 1 tatami size, causing a problem in terms of cost.

As described above, a method for producing a wooden board that can efficiently and stably contain a green tea polyphenol in the wooden board has not been known.
JP 2002-321205 A JP 2001-348968 A

  Therefore, an object of the present invention is to provide a method for producing a wooden board that can efficiently and stably contain a functional component such as green tea polyphenol in the wooden board, and a wooden board produced by the method. .

  As a result of investigations to solve the above problems, the present inventors have dried a wooden mat obtained by forming a wooden raw material, and then added an aqueous solution containing a functional component to the dried wooden mat. As a result, it has been found that the functional components can be efficiently and stably contained in the wooden board when the humidity is adjusted, and the present invention has been completed.

That is, the present invention provides the following wood board manufacturing method and wood board.
(1) A method for producing an antibacterial insulation board or wet board comprising a step of drying a wood mat obtained by forming a wood raw material and then conditioning the moisture, and drying an aqueous solution containing green tea polyphenol A method for producing an insulation board or a wet board , wherein the humidity is adjusted by adding to a later wood mat.
(2) The method according to (1), wherein the humidity control is performed by adding the aqueous solution in an amount of 7 to 15% by mass with respect to the dried wood mat, and then allowing the aqueous solution to stand for 12 hours or more.
(3) The (1) or the above characterized in that the aqueous solution is added to the dried wood mat so that the content of green tea polyphenol is 3.5 × 10 ^{−3 to} 1.0 g per 100 g of the wood board. (2) The method described.
(4) An insulation board manufactured by the method according to any one of (1) to (3) .
(5) A wet board manufactured by the method according to any one of (1) to (3).

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the wooden board which can make a wooden board contain functional components, such as green tea polyphenol, efficiently and stably, and the wooden board manufactured by this method are provided.

  The type of wood board to be manufactured in the present invention is not particularly limited, and examples of the wood board include an insulation board (soft fiber board), a hard board (hard fiber board), and a medium density fiber board (MDF). A fiber board such as Medium Density Fiberboard, a particle board, and the like. The manufacturing method of the present invention is particularly useful when an insulation board or a hard board is to be manufactured.

The insulation board is a soft fiber board having a density of less than 0.35 g / cm ³ that is produced by intertwining wood fibers, drying without heating, and as a production method thereof, for example, There is a method in which after fiberizing by steaming, defibration or the like, a wood mat is produced by sequentially adding water, a sizing agent, etc. and wet forming, drying the wood mat, and then conditioning and finishing.

The hard board is a hard fiber board having a density of 0.8 g / cm ³ or more produced by molding and hot pressing wood fibers. As a method for producing a wet hard board, for example, a wood raw material is steamed -After fiberizing by defibration etc., water, sizing agent, etc. are sequentially added to form a wooden mat by wet forming, and after heat-pressing the wooden mat, a method of conditioning and finishing is mentioned, As a manufacturing method of the dry hard board, for example, after making the wood raw material into a fiber by steaming, defibration, etc., the wood mat is manufactured by drying, adding an adhesive, a water repellent, etc., and dry forming, An example is a method in which the wood mat is hot-pressed and then conditioned and finished.

MDF is a medium density fiber board produced by molding and hot pressing wood fibers and producing a density of 0.35 g / cm ³ or more and less than 0.8 g / cm ³ . After the wood raw material is made into fiber by steaming, defibration, etc., it is dried, and then the wood mat is manufactured by dry forming with the addition of an adhesive, a water repellent, etc. And a finishing method.

  The particle board is a plate manufactured by pressing a small piece of wood at a high temperature and high pressure. As a method for producing the particle board, for example, the wood raw material is cut into pieces by cutting, crushing, etc., and then dried, adhesive, water repellent Examples include a method in which a wood mat is produced by adding an agent or the like and dry forming, and the wood mat is hot-pressed, and then conditioned and finished.

  As described above, any wood board manufacturing method includes a step of conditioning the humidity after drying (including drying by hot pressing) a wood mat obtained by forming a wood material.

  The wood raw material is not particularly limited as long as it can be prepared into a slurry. For example, demolition materials (for example, industrial waste materials, building waste materials), low quality chips, wood-based residual materials, forest land residual materials (for example, thinned wood), etc. Is mentioned.

  The tree species of the woody material is not particularly limited, and examples thereof include conifers such as cedar, cypress, hiba, and pine; broad-leaved trees such as chestnut, hippo, oak, shii, poplar, and willow; .

  The wood raw material is processed into a form that can be prepared into a slurry, if necessary, before being formed. Examples of such processing include fiberization by steaming / defibration, fragmentation (cutting) by cutting / crushing, and the like. Specific examples include wood fibers obtained by defibrating wood chips, wood powder obtained by pulverizing wood, wood powder such as sawdust generated in lumbering, and the like. It is also possible to use a mixture of wood fiber and wood powder as appropriate. Examples of means for obtaining a wood fiber by defibrating a wood chip or the like include a defibrator, a hammer mill, a ring breaker, and the like.

  From the viewpoints of slurry preparation, appearance of the produced wood board, permeability of the green tea polyphenol aqueous solution added to the wood mat, and the like, the fiber width of the wood fiber or wood powder is preferably 0.5 mm or less. Moreover, it is preferable that a wood fiber length is 10 mm or less from a slurry preparation, the external appearance of the manufactured wooden board, etc., and it is preferable that a wood powder length is 3 mm or less. However, if excessively fine fibers or powders are used, the wood board becomes brittle, and it may be necessary to use a large amount of binder in order to improve shape retention.

  The forming of the woody material can be performed according to a conventional method. For example, after preparing a slurry in which a wooden raw material is dispersed in water, the wooden raw material is molded by discharging water, and a wooden mat can be obtained. Water discharge from the slurry can be made by papermaking, that is, by supplying the slurry onto a filtering member such as a net and filtering the water, and by adjusting the ratio of the filtration area to the amount of slurry to be supplied, The thickness of the mat can be adjusted.

  In the case of manufacturing methods such as insulation boards and wet hard boards, the wood mat obtained by forming is dried. At this time, it is preferable to consider so that the drying of the wood mat proceeds uniformly throughout, and the moisture content immediately after drying is about 0 to less than 5% by mass. The drying temperature is usually 90 to 200 ° C, preferably 100 to 180 ° C, and the drying time is usually 3 to 24 hours.

  In the case of a manufacturing method such as dry hard board, MDF (medium density fiber board), particle board, etc., the wood mat obtained by forming is heated and dried. At this time, it is preferable to consider so that the drying of the wood mat proceeds uniformly throughout, and the moisture content immediately after drying is about 0 to less than 5% by mass. The drying temperature is usually 140 to 200 ° C., preferably 150 to 180 ° C., the pressurizing pressure is usually 1 to 10 MPa, and the drying time is usually 5 minutes to 2 hours, preferably 10 minutes to 1 hour.

  The humidity control performed after drying the wood mat is performed by adding an aqueous solution containing a functional component to the wood mat after drying. The addition of the aqueous solution containing the functional component can be performed, for example, by application to a wood mat, spraying, or the like.

  As a functional component, the plant extract which can provide a desired function to a wooden board is mentioned, for example. Examples of plant extracts that can impart antibacterial properties include, for example, tea extracts such as green tea extract, oolong tea extract, black tea extract, strawberry extract, apple peel extract, grape seed extract, hinoki extract, 孟 mune bamboo extract Products, mugwort extract, perilla extract, licorice extract and the like. The polyphenol contained in the tea extract, in particular the green tea polyphenol component, is extracted from, for example, juice or extraction (for example, water extraction) from tea husk or green tea leaves, from green tea silage where the green tea polyphenol described in JP-A No. 2002-272385 remains. It can be obtained by squeezing or extracting (for example, water extraction). As green tea, use the genus Camellia (for example, C. sinensis, C. assamica), Yabukita seeds, tea leaves made from those hybrids, etc., sencha, bancha, gyokuro, tencha, tea in pots, etc. Can do. Extraction of green tea polyphenols can be performed according to conventional methods. Examples of the green tea polyphenol include non-epimeric catechins such as catechin, gallocatechin, catechin gallate, and gallocatechin gallate; and epicatechins such as epicatechin, epigallocatechin, epicatechin gallate, and epigallocatechin gallate. .

  Examples of plant extracts that can impart organic substance capturing ability, such as formaldehyde capturing ability, include tea extracts such as green tea extract, oolong tea extract, and black tea extract, apple peel extract, and grape seed extract. Examples of plant extracts that can impart a deodorizing function include tea extracts such as green tea extract, oolong tea extract, and black tea extract, hinoki extract, and Tsutsutake bamboo extract.

  Humidity adjustment may be performed at any time after drying the wood mat, but is usually performed immediately after drying the wood mat. The amount of the aqueous solution containing the functional component is preferably adjusted so that the moisture content in the wood board product is 5 to 13% by mass. Specifically, the addition amount of the aqueous solution containing the functional component is preferably 7 to 15% by mass of the dried wood mat. When the moisture content of the wooden board is less than 5% by mass, moisture in the atmosphere is absorbed and the size of the wooden board is not stable, while when the moisture content of the wooden board is 13% by mass or more, moisture is released. The dimensions are distorted. Moreover, in JISA5905, it is described that the moisture content of an insulation board and a hard board exists in the range of 5-13 mass%.

When the functional component is green tea polyphenol, the addition amount of the aqueous solution containing green tea polyphenol can be adjusted so that the content of green tea polyphenol is 3.5 × 10 ^{−3 to} 1.0 g per 100 g of wooden board. preferable. When the content per 100 g of the wooden board is less than 3.5 × 10 ⁻³ , sufficient antibacterial properties cannot be obtained, and when the wooden board is over 3.0 g, the wooden boards adhere to each other. Incurs quality degradation.

  The wood mat after the addition of the aqueous solution containing the functional component is preferably left for 12 hours or more after being laminated as necessary for the purpose of infiltrating the green tea polyphenol aqueous solution. If the standing time is less than 12 hours, the components may not uniformly penetrate into the wooden board and may cause unevenness.

  The wooden board produced by the present invention contains functional components efficiently and stably, and has superior functionality compared to conventional wooden boards (antibacterial when the functional component is green tea polyphenol). ).

  Hereinafter, the present invention will be described in detail based on examples. Note that the scope of the present invention is not limited by these examples.

[Examples A1 to 2, Comparative examples Z1 to 6]
Using a mixer, white paper and water were stirred for 5 minutes to form a slurry to prepare a paper fiber slurry having an absolute dry weight ratio of 2% by weight. White paper was used for the purpose of eliminating the influence of the tannin content of the wood component. The paper fiber slurry was dehydrated by applying a pressure of 300 kg / m ² to obtain a dehydrated liquid. The mat-like molded product after dehydration was dried at 140 ° C. for 3 hours. Immediately after drying, green tea polyphenol (product name: Theafuran 30A, manufactured by ITO EN Co., Ltd., see Table 1 for the composition) 3% by weight aqueous solution with a predetermined blending ratio (Table 2) to obtain a catechin-containing insulation board (Examples A1 and A2). In Table 1, “EGC” represents epigallocatechin, “EGCg” represents epigallocatechin gallate, “EC” represents epicatechin, and “ECg” represents epicatechin gallate.

On the other hand, green tea polyphenol (product name: Teafuran 30A, manufactured by ITO EN Co., Ltd., see Table 1 for the composition) is mixed with the paper fiber slurry at a predetermined blending ratio (see Table 2), and the mixture is evenly placed on a 100 mesh metal net. And then matted into a mat. The molded mat was dehydrated by applying a pressure of 300 kg / m ² to obtain a dehydrated liquid. The mat-like molded product after dehydration was dried at 140 ° C. for 3 hours to obtain a catechin-containing insulation board (Comparative Examples Z1 to Z3).

Further, the paper fiber slurry was uniformly spread on a 100-mesh metal net and molded into a mat shape. The molded mat was dehydrated by applying a pressure of 300 kg / m ² to obtain a dehydrated liquid. A green tea polyphenol (product name: Theafuran 30A, manufactured by ITO EN Co., Ltd., see Table 1 for the composition) is added to the mat-like molded product after dehydration with a predetermined blending ratio (see Table 2, the amount added is based on the weight of the dry paper fiber) (Described by weight ratio) and dried at 140 ° C. for 3 hours to obtain a catechin-containing insulation board (Comparative Examples Z4 to 6).

The residual ratio of the green tea polyphenol amount in each catechin combination insulation board was calculated based on the following formula.
Survival rate(%)
＝ {1- (Green tea polyphenol content in dehydrated liquid) / (Additive green tea polyphenol content)} × 100

  As shown in Table 2, when the green tea polyphenol blending time is before matting (Comparative Examples Z1 to 3) or after matting and before drying (Comparative Examples Z4 to 6), runoff and decomposition of the green tea polyphenol occurs. The residual ratio in the product with respect to the added amount was small, whereas in the case after matting and drying (Examples A1 to 2), the residual ratio in the product with respect to the added amount was remarkably high.

[Examples B1-5, Comparative Examples Y1-5]
After 10 commercially available hard boards cut to 15 cm × 15 cm were dried at 105 ° C. for 3 hours, a predetermined amount (see Table 3) of green tea polyphenol aqueous solution was sprayed on each of the 10 boards, and they were superposed for 1 hour and 6 hours. The moisture content after 12 hours and 24 hours was measured, and the surface state was observed.

  The surface state was observed as follows. The top and bottom contact plates were removed one by one from the 10 stacked hard boards, and the surface of the 8 hard boards was observed and judged by the following method.

[Evaluation criteria]
○: Not wet. (All eight surfaces have the same color)
X: Wet. (There is a black part on the surface of one or more sheets)
Pass / fail judgment: ○ passes

The moisture content was measured as follows. Remove the upper and lower ones from the 10 stacked hard boards, measure the weight change after drying at 105 ° C for 3 hours for each of the 8 hard boards, and determine the moisture content based on the following formula: Calculated.
Water content (%) = {(weight before drying−weight after drying) / weight before drying} × 100

[Evaluation criteria]
○: Moisture content 5% or more and less than 13% (JISA5905 compliant product)
×: Moisture content of 13% or more or moisture content of less than 5%

  As shown in Table 3, when the added amount of the aqueous solution is 7 to 15% with respect to the dry weight of the board and the time for which the moisture is absorbed by the board (the standing time) is 12 hours or more, the stable moisture in the final product The rate was found to be obtained.

[Examples C1-6]
Eight commercially available hardboards (1 sheet: 100 g) are dried at 120 ° C. for 3 hours, and after removing the contained water, green tea polyphenol (product name: Tearfuran 30A, manufactured by ITO EN Co., Ltd., see Table 1 for composition) Was sprayed and overlaid with a green tea polyphenol aqueous solution so as to be a predetermined amount (see Table 4). After being left for 24 hours, the upper and lower contact plates were removed, and the sample was subjected to an antibacterial activity evaluation test and the presence or absence of adhesion between the boards.

  The antibacterial activity evaluation test method is as follows. Cut the hardboard sample into 5cm x 5cm, immerse it in 1/500 ordinary broth, and then use the film adhesion method of the Antibacterial Products Technical Council to live the bacterial solution (MRSA: methicillin-resistant Staphylococcus aureus) on the sample The number (CFU / sheet) was measured.

[Evaluation criteria]
A: The number of viable bacteria after 24 hours was less than 2.0 × 10 ³ .
X: The number of viable bacteria after 24 hours was 2.0 × 10 ³ or more.
Pass / fail judgment: ○ passes

The evaluation criteria for the presence or absence of adhesion between boards are as follows.
[Evaluation criteria]
○: No adhesion between boards.
X: There is adhesion between boards.
Pass / fail judgment: ○ passes

As shown in Table 4, by adjusting the added amount of green tea polyphenol to 3.5 × 10 ^{−3 to} 1.0 g per 100 g of dry wood board, antibacterial activity and quality stability in the final product can be obtained. Turned out to be.

[Examples D1 to 4, Comparative Examples X1 to 4]
In the same manner as in Examples C1 to 6, 8 commercially available hardboards (1 sheet: 100 g) were dried at 120 ° C. for 3 hours, and after removing the contained water, green tea polyphenol (product name: Teafuran 30A, manufactured by ITO EN Co., Ltd., composition) Were sprayed with a green tea polyphenol aqueous solution so that the addition amount (see Table 1) was a predetermined amount (see Table 5). After leaving for 24 hours, the upper and lower patch plates were removed, and the sample was subjected to an antibacterial activity evaluation test (Examples D1 to D4).

  Without drying 8 commercially available hardboards (1 sheet: 100 g), the added amount of green tea polyphenol (product name: Tearfuran 30A, manufactured by ITO EN Co., Ltd., see Table 1 for composition) is a predetermined amount (see Table 5). Thus, the green tea polyphenol aqueous solution was sprayed, dried at 120 ° C. for 3 hours, left and left for 24 hours, the upper and lower backing plates were removed, and the antibacterial activity evaluation test for the samples was performed (Comparative Examples X1 to 4).

  The antibacterial activity evaluation test method is as follows. Cut the hardboard sample into 5cm x 5cm, immerse it in 1/500 ordinary broth, and then use the film adhesion method of the Antibacterial Products Technical Council to live the bacterial solution (MRSA: methicillin-resistant Staphylococcus aureus) on the sample The number (CFU / sheet) was measured.

[Evaluation criteria]
A: The number of viable bacteria after 24 hours was less than 2.0 × 10 ³ .
X: The number of viable bacteria after 24 hours was 2.0 × 10 ³ or more.
Pass / fail judgment: ○ passes

As shown in Table 5, it was found that antibacterial activity can be obtained even in the final product by drying a commercially available hardboard, removing the water content, and adding green tea polyphenol. However, drying a commercially available board again may cause problems in terms of quality stability and cost of the board itself.

Claims (5)

A method for producing an antibacterial insulation board or wet hardboard , comprising a step of drying and then conditioning the wood mat obtained by forming the woody raw material, after drying an aqueous solution containing green tea polyphenol A method for producing an insulation board or a wet hardboard , characterized in that the humidity is adjusted by adding to a wooden mat.   2. The method according to claim 1, wherein the humidity control is performed by adding the aqueous solution in an amount of 7 to 15% by mass based on the dried wood mat, and then allowing the aqueous solution to stand for 12 hours or more. The method according to claim 1 or 2 , wherein the aqueous solution is added to the dried wood mat so that the content of green tea polyphenol is 3.5 x 10 ^{-3 to} 1.0 g per 100 g of the wood board. . The insulation board manufactured by the method in any one of Claims 1-3 . The wet hard board manufactured by the method in any one of Claims 1-3.