JP2010013753A - Water-repellent, highly humidity-conditioning japanese paper sheet material and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water-repellent, highly humidity-conditioning Japanese paper sheet material having excellent humidity-conditioning functions over medium humidity and high humidity regions and even having a thin shape while having feeling and texture of Japanese paper, providing excellent designability and operability, and mild to the environment after disposal, and to provide a method for producing the sheet material. <P>SOLUTION: The water-repellent, highly humidity-conditioning Japanese paper sheet material is produced as follows. A natural fiber material of an auxiliary feedstock, having a diameter nearly equal to that of a hemp fiber material of a main feedstock and also having good entangling properties is mixed with the hemp fiber material, and a fiber material having an average fiber diameter and an average fiber length smaller than those of the hemp fiber material and the natural fiber material is added thereto as a space-regulating fiber material. The resultant mixture is subjected to papermaking to provide a base material paper layer 1. A humidity-conditioning paper layer 2 formed on the base material paper layer 1 in a layered state by papermaking, and obtained by adding a calcium silicate hydrate powder having a prescribed particle degree not permeating into the fiber space of the base material paper layer 1 to the hemp fiber material and the natural fiber material of the auxiliary feedstock contained in the base material paper layer 1, and a decorative paper layer 3 formed on the humidity-conditioning layer 2 in a layered state by papermaking, obtained by applying water-repellent processing onto the surface and having air permeability are laminated and integrated on the base material paper layer 1. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention is an improvement of a humidity control sheet material mainly used for interiors. Specifically, the relative humidity of an indoor space ranges from a medium humidity range (relative humidity 50 to 75%) to a high humidity range (relative humidity 75 to 100%). The present invention relates to a water-repellent high-harmonic humidity Japanese paper sheet material that is capable of autonomously adjusting humidity and that is thin, strong, and resistant to dirt, and is very convenient in terms of manufacturing, and a method for manufacturing the same.

  In recent years, in order to prevent unpleasant moisture and dew condensation in the indoor environment, the use of interior building materials with humidity control in the middle to high humidity range has progressed, and the main common problem of these humidity control building materials is However, there is a question of how efficiently the desired functional inorganic powder is supported on the base layer. As a solution, organic emulsions and synthetic resins are used as binders, and humidity control building materials with various compositions and structures have been proposed. ing.

  As a general standard for humidity conditioning performance in such humidity conditioning materials, the Japan Building Materials Industry and Housing Equipment Association established the “Regulation for Humidity Control Building Material Registration and Display” for the purpose of ensuring the reliability of humidity conditioning building materials. (Non-Patent Document 1).

According to this regulation, when the relative humidity is changed from 50% to 75%, it absorbs 29 g / m ² or more within 12 hours, and in the process of releasing moisture from 75% to 50%, 70% of the moisture absorption within 12 hours. It is said that those having a moisture release amount satisfy the humidity control performance standard.

  The above test method is defined in detail in “JIS A 1470-1”, but it is usually difficult to pass the certification standard unless it is a thick product such as boards, like wallpaper. No thin material that meets the standards currently exists.

  Conventionally, as moisture-conditioned Japanese paper wallpaper, a moisture absorbing / releasing layer in which an inorganic porous material carries an organic emulsion as a binder is applied and formed on the surface of a flexible substrate such as pulp fiber, nonwoven fabric, film, etc. Wallpapers and water-repellent humidity control members (Patent Documents 1 and 2) are known.

  However, although these materials and methods are excellent in terms of flexibility and manufacturing cost, inorganic powder having functions such as humidity control is supported on an organic emulsion on a substrate made of nonwoven fabric, paper, plastic film, etc. In addition to the decrease in moisture permeation performance due to the organic emulsion, it is limited in terms of design as well, and in the light and thin sheet-like wall material having the texture of Japanese paper, <Non-Patent Document 1> It was not possible to satisfy the humidity control performance standards in a short time in the medium humidity range as described in the above.

  Further, <Patent Document 2> describes a method for ensuring air permeability even when the organic emulsion is dried and cured by using water-repellent powder in order to ensure moisture permeability while using the organic emulsion. Even in this case, since the support on the base material is a coating drying and curing method, increasing the humidity conditioning performance per area and satisfying the certification standard will increase the thickness and increase the weight per unit area, In addition, the seams at the time of construction are conspicuous, and there are also other disadvantages such as the inability to impart the texture of Japanese paper, and there are also problems in terms of environmental impact after disposal due to difficulty in recycling.

  In addition, as a functional layer formed by a papermaking method, a sandwich paper in which a granular additive having excellent humidity control properties such as charcoal, apatite, zeolite, etc. is used as an intermediate layer, and Japanese paper is laminated on both sides thereof (Patent Document 3). Also known is deodorized moisture-controlled paper (Patent Document 4) that is supported in an aggregated floc form with natural fiber materials such as artificial zeolite powder and pulp.

  However, <Patent Document 3> only describes a sandwich structure, and in a normal Japanese paper manufacturing method, powder flows out of the base layer during papermaking, or in the cutting process during construction, an end portion is used. In other words, the functional particles of the powder fall off, the humidity control performance of the powder is low, and the criteria described in <Non-Patent Document 1> cannot be satisfied.

  Furthermore, as can be seen in <Patent Documents 2 and 3>, the wallpaper that relies on zeolite for humidity control performance has high hygroscopicity in the low humidity range, but the hygroscopic property in the medium and high humidity ranges. In addition, since the moisture release capacity is as small as it is not, it is impossible to ensure the performance as required by <Non-Patent Document 1>.

  In addition, as humidity control building materials, humidity control boards made of rock wool board with moisture absorption / release materials such as activated carbon, silica gel, zeolite, allophane, etc. It has been proposed (Patent Document 5).

  However, plate materials and inorganic tiles such as those found in <Patent Document 5> are not flexible and have poor workability such as cutting work and pasting work, heavy weight per unit area, and labor costs. There was a problem that it was more expensive than those based on paper materials.

  In addition, when using non-woven fabric or synthetic fiber for the intermediate layer or surface layer of the sheet, it is difficult to carry inorganic powder in papermaking molding as in Japanese paper, and entanglement and familiarity with pulp fibers are poor, making it difficult to produce by papermaking method. In addition, it is difficult to impart various design properties of Japanese paper, and it is also difficult to satisfy the certification standard of <Non-Patent Document 1>.

Furthermore, when conventional Japanese paper is used as an interior wall material, the antifouling property has been a major issue. In recent years, water repellent treatment has been required and some products have been commercialized. The water repellent coating method has a problem of inhibiting humidity control.
Humidity control building material registration and labeling regulations related to “Humidity control building material registration and labeling system” issued by Japan Building Materials Industry and Housing Equipment Industry Association JP-A-2004-300648 JP 2005-105433 A JP 2004-52152 A Japanese Patent Application Laid-Open No. 2004-277782 JP2003-20734

  The present invention has been made in view of the problems as described above, and the object of the present invention is to maintain the texture and texture of Japanese paper, and even in the thin and high humidity range, even in the thin shape. Another object of the present invention is to provide a water repellent and high-humidity Japanese paper sheet material that has an excellent humidity control function, is excellent in design and workability, and is environmentally friendly after disposal, and a method for producing the same.

  Means employed by the present inventor for solving the above-described problems will be described with reference to the accompanying drawings.

That is, the present invention mixes a hemp fiber material, which is a main raw material, with a natural fiber material of an auxiliary material that has substantially the same diameter and good entanglement, and further, these hemp fiber material and natural fiber material A base paper layer 1 made by adding a fiber material having a smaller average fiber diameter and average fiber length as a gap adjusting fiber material;
The base paper layer 1 is made into a layered state, and the hemp fiber material and auxiliary natural fiber material contained in the base paper layer 1 are impermeable to the fiber gaps of the base paper layer 1. A humidity control paper layer 2 mixed with calcium silicate hydrate (hereinafter abbreviated as “C—S—H”) powder of a predetermined particle size;
It is characterized in that it is integrally formed by laminating a breathable decorative paper layer 3 formed on the humidity-controlling paper layer 2 in a layered state and having a water repellent finish on the surface. is there.

  Moreover, in order to solve the said subject, in addition to the said means, this invention makes the hemp fiber material of the base paper layer 1 contain hemp fiber material at least 50% or more by dry weight ratio as needed. Technical means can be adopted.

  Moreover, in order to solve the said subject, this invention adds the said means as needed, the humidity-control paper layer 2, C-S-H powder is dry weight ratio 25-70%, hemp fiber It is possible to employ a technical means of including at least 30% or more of a natural pulp fiber composed of wood, softwood pulp fiber and hardwood pulp fiber in a dry weight ratio and bonding them with a natural polymer binder.

  Moreover, in order to solve the said subject, in addition to the said means as needed, this invention is the decorative paper layer 3 which is the design layer of the upper part of the basic paper layer 1 and the humidity-control paper layer 2 in a dry weight ratio. It is possible to employ a technical means that 80 to 90% of hemp fiber material and fibers mainly composed of softwood pulp are mixed and made at a dry weight ratio of 10 to 20%.

  Further, in order to solve the above-described problems, the present invention provides a technical means in which a water repellent is attached and processed in a dot-like manner on the fine top of the surface irregularities of the decorative paper layer 3 in addition to the above means as necessary. Can be adopted.

  In addition, in order to solve the above-mentioned problems, the present invention, in addition to the above-described means, the C—S—H powder of the humidity control paper layer 2 has a particle diameter of 1 μm or more and is subjected to heat dehydration treatment. Technical means can be adopted.

  Further, in order to solve the above-mentioned problems, the present invention provides technical means for making the hemp fiber material in the main raw material of the base paper layer 1 and the humidity control paper layer 2 into manila hemp fibers in addition to the above means as necessary. Can be adopted.

  In addition, in order to solve the above-described problems, the present invention provides a technical technique in which a natural fiber material as a secondary raw material in the base paper layer 1 and the humidity control paper layer 2 is conifer pulp fiber in addition to the above-described means as necessary. Means can be employed.

  Moreover, in order to solve the said subject, in addition to the said means as needed, this invention can employ | adopt the technical means of making the clearance adjustment fiber material in the base paper layer 1 into hardwood pulp fiber.

  In order to solve the above problems, the present invention provides a vegetable binder comprising a natural polymer in each of the base paper layer 1, the humidity control paper layer 2 and the decorative paper layer 3 in addition to the above means as necessary. Technical means of mixing the materials can be employed.

  Moreover, in order to solve the said subject, in addition to the said means as needed, this invention can employ | adopt the technical means of making the main raw material of the decorative paper layer 3 into a hemp fiber material.

  Further, in order to solve the above-mentioned problems, the present invention uses a hemp fiber material as a main raw material in addition to the above means as necessary, and is a natural fiber material having substantially the same diameter as this and having good entanglement. As a secondary raw material, dispersed in water together with a vegetable binder, and further added as a gap adjusting fiber material a fiber material having an average fiber diameter and an average fiber length smaller than those of the hemp fiber material and natural fiber material. After preparing a base stock liquid and making a base paper layer containing each of the fibers from the base stock liquid, the main raw material is dried before the base paper layer is dried. Humidity control paper stock prepared by mixing a CSH powder having a predetermined particle size that is impermeable to the fiber gaps of the base paper layer into a stock solution containing hemp fiber material and natural fiber material of auxiliary material The liquid is drawn out to form a humidity control paper layer, and then, before the base paper layer and the humidity control paper layer are dried, On the moisture-controlling paper layer, paper fibers are drawn from a paper solution made of a paper fiber material, and a decorative paper layer is formed and dried. After that, the surface of the decorative paper layer is repelled. A technical means of applying water processing can be employed.

  In the present invention, it combines excellent humidity control and high strength in the middle humidity region among plant fibers, and papermaking a base paper layer using hemp fiber material as a main raw material, on the base paper layer, As with the base paper layer, hemp fiber material that is thick and easy to form a lot of gaps for supporting powder is used as the main raw material, and humidity control performance in high humidity range is also achieved in diatomaceous earth. Producing a Japanese paper sheet material that exhibits high humidity control performance autonomously from a medium humidity range to a high humidity range by mixing a C-S-H powder that is about three times higher than that of the humidity control paper layer. In addition, the sheet material can be made thinner and lighter than when the humidity control performance of the same level is realized using diatomaceous earth.

  In addition to the hemp fiber material of the main raw material and the natural fiber material of the auxiliary raw material, a fiber material for gap adjustment having a small fiber diameter and fiber length is added to the base paper layer to reduce the size of the gap between the fibers. By making it smaller, the fine C—S—H powder is easily caught by the fibers of the base paper layer when producing the humidity control paper layer, and a filter effect is produced. Can be improved and the manufacturing cost can be reduced.

  In the present invention, the decorative paper layer is further formed on the humidity control paper layer to improve the design, and by interposing this decorative paper layer, the C—S—H powder of the humidity control paper layer is removed. When the surface of the decorative paper layer is subjected to a water-repellent treatment that imparts an antifouling effect, the problem that the water-repellent agent directly adheres to the CSH powder is also solved.

  Furthermore, according to the present invention, since the base paper layer has sufficient strength at the paper making stage, the powder in the slurry that becomes the humidity control paper layer is left with a high yield, and the humidity control paper layer is a hemp fiber material. And natural pulp fibers, such as softwood pulp fibers, can firmly and massively support C—S—H, which is a humidity-controlling powder for improving the humidity-control function in the middle-humidity region and increasing the high-humidity region.

  In addition, the surface layer of the decorative paper layer enables a variety of designs with the texture of Japanese paper, and the water-repellent high-humidity humidified Japanese paper sheet conforms to the moisture-conditioning building material certification standards by the water-repellent treatment applied to the outermost surface of the decorative paper layer. Since a material is obtained, it is possible to provide a comfortable humidity environment for indoor air by using this as an interior wall material to develop a self-sustaining humidity control function.

  In addition, most of the conventional humidity control wall materials for interior use are boards and tiles, and there is a drawback that the seam is conspicuous because of the thickness, and similar sheet-like products have the same disadvantage. In the water-repellent moisture-controlled Japanese paper sheet of the present invention, since the decorative paper layer is made of Japanese paper fiber material, the surface layer fibers overlap each other by making the joints uniform even after construction, so that the surface layers overlap. Can do.

  Furthermore, the product of the present invention is mainly composed of natural raw materials such as fiber material and binder, and the heat-dehydrated CSH used as the humidity control powder is composed of silicic acid and calcium. Since it can be used as a material, it is extremely environmentally friendly.

  In addition, the present invention is not a method for controlling only the particle diameter and fiber length as in the prior art, but the fiber as a base material is made of high-strength Manila hemp as a main raw material. In order to optimize the amount and size of papermaking and the amount of gap caused by fiber entanglement by using conifer pulp with fiber width and broad-leaved wood pulp with narrower fiber width, etc., to form a humidity control paper layer The function of the particles as a permeation prevention filter can be imparted, and the product strength can be satisfied.

  Therefore, it is possible to provide a high-humidity humidity sheet material that is not only superior in humidity control function as a humidity control building material, but also very advantageous in terms of use and manufacturing, premised on mass production. The practical use value of the present invention is very high because it can be used over a wide range of moisture absorption and deodorization by placing it in a chest or in a clog box.

  BEST MODE FOR CARRYING OUT THE INVENTION The best mode for carrying out the present invention will be described in more detail with reference to the drawings specifically shown as follows.

  An embodiment of the present invention is shown in FIGS. In FIG. 1, what is indicated by reference numeral 1 is a base paper layer, and what is indicated by reference numeral 2 is a humidity control paper layer. What is indicated by reference numeral 3 is a decorative paper layer.

  First, the base paper layer 1 will be described. This base paper layer 1 is mixed with the main raw material hemp fiber material, the auxiliary raw material natural fiber material having substantially the same diameter as the hemp fiber material and having good entanglement with the hemp fiber material. Further, the fiber is formed from a material obtained by adding a fiber material having an average fiber diameter and an average fiber length smaller than those of the hemp fiber material and natural fiber material as a gap adjusting fiber material. The main raw material refers to a raw material occupying the largest part by weight (particularly 50% or more) with respect to the total weight of the mixed material.

  The hemp fiber material used for the base paper layer 1 (and the humidity control paper layer 2 to be described later) has high strength in addition to the humidity control function in the middle humidity range, good fiber entanglement, and fine pores between the fibers. In order to prevent the C—S—H powder from being washed away in the paper making process (in the slurry) of the humidity-controlling paper layer 2 to be described later, the fiber diameter is 15 to 40 μm among natural fibers. Using thick and durable Manila hemp fiber, the natural fiber material of the auxiliary material has a humidity control function in the middle humidity range like hemp fiber material, and the fiber width is substantially the same as that of Manila hemp fiber. It is ˜30 μm, and softwood pulp fibers that are very easily entangled with the hemp fiber material are used.

  In addition, sisal hemp, kenaf, jute, etc. other than manila hemp can be used as the main raw material hemp fiber material. Basically, other than softwood pulp fibers can be used as long as they are easily entangled with the hemp fiber material and have the same length and thickness as the hemp fiber material.

  In this embodiment, the softwood pulp fiber of a subsidiary material is mix | blended in the ratio (wt%) of about 9: 1 with respect to the Manila hemp fiber of a main raw material.

  Further, the gap adjusting fiber material added to the base paper layer 1 has a high humidity control performance in the middle humidity range compared to the hemp fiber material and softwood pulp fiber, and a very thin hardwood having a fiber diameter of about 5 to 15 μm. It is desirable to use pulp fibers.

  This gap-adjusting fiber material (especially hardwood pulp fiber) has the narrowest fiber width among natural pulp, and many branches occur in the fiber by beating, so the gap between the fibers is narrow and the filter effect to trap particles Although it can be further increased, if it is used in a large amount, dehydration (drainage) at the paper making stage becomes poor, so it is desirable to suppress it to about 10 wt%.

  In addition, it is preferable that the gap adjusting fiber material has a humidity control function. However, if the fiber material has an average fiber diameter and an average fiber length smaller (thin and shorter) than hemp fiber material or natural fiber material, it is a hardwood. It is possible to select appropriately from other than pulp fibers, and it is also possible to employ a compound fiber in which the fiber diameter and fiber length can be easily set.

  Next, the humidity control paper layer 2 will be described. The moisture conditioning paper layer 2 is a layer provided on the base paper layer 1 and is a hemp fiber material having a thickness and length of fibers (in this embodiment, an appropriate gap is formed between the fibers. "Manila hemp fiber") is used as a main raw material, and softwood pulp fiber with entanglement is mixed as an auxiliary raw material, and further C-S-H powder having a particle size of 1 to 100 μm is added thereto. It is a thing.

  As this C—S—H powder, heat-dehydrated C—S—H is used because a highly-conditioned humidity control powder with good entanglement between the powder and fibers is effective. Details are described in the reference document “J. Ceram. Soc. JAPAN 113 [11] 736-742 (2005)”.

  In addition, this heat-dehydrated C—S—H is extremely high humidity control performance that is more than three times that of conventional calcium silicate building materials and diatomaceous earth, which is a commonly used inorganic powder. It is a substance having

  In addition, this material is a collection of acicular particles in the shape of the pulverized material, so it has the property of being easily entangled with fibers during papermaking and can be manufactured in large quantities at low cost. There is no problem from the aspect of environmental load, such as satisfying the certification standards.

  Normally, C—S—H, which is a substance having a nano-level gap between crystal layers and heated and dehydrated in a range of 110 ° C. to 700 ° C., is used. It is preferable to use dehydrated C—S—H. When high whiteness is required, C—S—H synthesized from a raw material with a small amount of iron compounds contained as impurities is used or included. It is desirable to use C—S—H that has been heat-dehydrated in a low temperature range where the iron compound is not oxidized.

  In order to ensure high humidity control performance in a short period of time in the medium humidity region in the humidity control paper layer 2, it is necessary to mix a mixed fiber material composed of Manila hemp fibers and softwood pulp fibers at an internal rate of 20 wt% or more. is there.

  Moreover, it is desirable to determine the blending ratio between the C—S—H powder and the mixed fiber material in consideration of the balance of the humidity control function between the medium humidity region and the high humidity region. Note that when the C—S—H powder is contained in an amount of 25% or more, the humidity-controlling paper layer 2 can be provided with flame retardancy.

  Finally, the decorative paper layer 3 will be described. The decorative paper layer 3 is a layer provided on the humidity-controlling paper layer 2 and is made of hemp fiber material and softwood pulp fiber. The surface is water repellent and has air permeability. ing.

  In addition, in order to enable various designs while maintaining the breathability while maintaining the breathability of Japanese paper, natural fibers for Japanese paper with relatively long fiber lengths such as hemp fiber material, Kozo, and Mitsumata are used as the main raw material. Designability and functionality can be secured.

  In addition, from the viewpoint of design and functionality, the decorative paper layer 3 can be mixed with artificial fibers, other functional powders, coloring materials, and the like while using natural pulp fibers as a main raw material. The mixed fiber material, for example, ensures the texture and functionality of the Japanese paper, strongly integrates the layers, increases the strength of the Japanese paper, and improves the flow of moisture to the humidity control paper layer. In order to increase the air permeability, it is desirable that 10 to 20 parts by weight of softwood pulp is blended with a natural fiber material having thick and long Manila hemp fiber material or mulberry as a main raw material. At this time, rayon, colored fibers, colored pigments, and the like can also be blended, and the surface can be embossed to impart design properties.

  In addition, the water repellent used for the water repellent finish of the decorative paper layer 3 is preferably a silicone water repellent from the viewpoint of safety, price, environmental load, etc., but may be non-aqueous, such as oily smoke. Fluorine-based water repellent may be used when anti-staining is required.

  The base paper layer 1, the humidity control paper layer 2, and the decorative paper layer 3 having different functions and roles, which are configured as described above, are sequentially laminated (the ratio of the thickness of each layer in this embodiment is about 1: 3: 1) and integration makes it possible to form a sheet material having a high humidity control function from a middle humidity range to a high humidity range, and being thin and durable with high design properties.

"Production method of sheet material"
The manufacturing method of the sheet material of this embodiment will be described in detail below. First, hemp fiber material is used as the main raw material, and natural fiber material that is approximately the same diameter as this hemp fiber material and has good entanglement with this hemp fiber material is used as a secondary raw material and is freely released in water together with the binder. Disperse and mix.

  A natural polymer binder that does not inhibit moisture absorption / release properties is used as the binder, while mixing, kneading, and moisture adjustment are performed, and the resulting slurry is poured onto the base layer for paper dehydration. In the subsequent process, the C—S—H particles sink into the gaps between the fibers and are crushed and entangled more strongly with both fiber materials, so that they can be firmly supported and integrated without using an organic emulsion.

  At this time, if a vegetable binder made of a natural polymer such as troro-aoi is used, not only the humidity control performance of the sheet material is further improved, but also the plant fiber is added to the fiber material of each paper layer because it has biodegradability. If only is used, the sheet material can be made very environmentally friendly.

  Then, a base material liquid is prepared by adding a fiber material having an average fiber length smaller than that of the hemp fiber material and natural fiber material as a gap adjusting fiber material, and each of the fibers is included from the base material liquid. The base paper layer 1 is removed.

  In addition, the dewaterability at the time of papermaking can be suitably adjusted by changing the magnitude | size of a fiber gap | interval by increasing / decreasing the compounding quantity of fine fine hardwood pulp fiber.

  The hardwood pulp fiber used as the gap adjusting fiber material has the narrowest fiber width among the natural pulp fibers, and the fiber has many branches due to beating. If used, the water loss of the base paper layer 1 at the paper making stage will be poor, so the blending ratio is desirably suppressed to about 10 wt%, and the beating treatment conditions are preferably determined experimentally.

  Then, before the paper base paper layer 1 is dried, the C—S—H powder having a particle size of 1 μm to 5 mm is added to the paper stock liquid containing the main raw material hemp fiber material and the auxiliary raw material natural fiber material. The humidity-controlling paper stock solution prepared by mixing the paper is made and the humidity-controlling paper layer 2 is deposited. At this time, by adding starch to the humidity control paper layer 2, the entanglement between the CSH powder and each fiber material is further strengthened, and the powder at the time of cutting when the sheet is applied is reduced. Dropout can be prevented.

  When making the humidity control paper layer 2, in order to achieve high humidity control within a short period of time in the middle humidity range, fiber materials made mainly of manila hemp and softwood pulp as natural fibers are used for the humidity control powder. A moisture absorption / release layer is formed by a papermaking method using a natural polymer binder such as starch or troro-aoi that does not impair the moisture absorption / release performance. Is desirable.

  At this time, it is desirable that the blending ratio of the C—S—H powder and the fiber is within a range in which the humidity control function exceeds the certification standard and also the flame retardant certification standard can be satisfied. In order to improve functionality, other flame retardants can also be used as appropriate.

  Next, before the base paper layer 1 and the humidity control paper layer 2 are dried, the paper fibers are made from the paper solution made of the paper fiber material on the humidity control paper layer 2 to make the decorative paper layer 3. Is layered and dried.

  Thereafter, the outermost surface of the decorative paper layer 3 is coated with a water repellent. In the present embodiment, for uniform surface treatment, it is preferable to rotationally contact a sponge-like roller containing a water repellent, and it is possible to attach only to the outermost fibers and perform water repellent treatment in the form of fine dots. it can. Impregnation and spraying methods are also possible. Thus, the sheet material of this embodiment is completed.

  This sheet material is classified as “Japanese paper” because it uses 50% or more of hemp, a bast fiber, and is made using a natural polymer binder (so-called “neri”). It can be said that. On the other hand, wood paper contains 50% or less of wood pulp fiber as a raw material.

  In addition, after the decorative paper layer 3 is formed, the entire sheet material can be pressed to be 1 to 5 mm in thickness, and the convenience in construction and finishing such as cutting work and seam processing can also be achieved. Can be secured. At the time of this pressing, the C—S—H powder can be rolled or pulverized to a required size. Furthermore, an embossing process can be performed on the surface of the decorative paper layer 3 to form a concavo-convex pattern to impart design properties.

  According to the manufacturing method described above, since the size of the gap between the fibers is reduced by the gap adjusting fiber material added in the base paper layer 1, a fine C—S—H powder is produced at the time of making the humidity control paper layer 2. The body is easily caught by the fibers of the base paper layer 1, and the leakage of the powder is suppressed and the yield is improved.

  Below, each test result about the various physical properties of the sample of this embodiment is shown.

<Humidity adjustment test for fiber material of base paper layer 1>
First, the humidity control test regarding the fiber materials (manila hemp fiber, conifer pulp fiber) used for the base paper layer 1 of the present embodiment was performed. As a test method, each test specimen made by papermaking so that the dry fiber weight per square meter is 1 kg is equilibrated in a constant temperature and humidity chamber at 23 ° C. and 50% RH (Relative-Humidity) for 12 hours. After that, the humidity was changed to 75% RH, and the moisture absorption test in the middle humidity range was adopted by the humidity response method in accordance with “JIS A 1470-1” which measures the weight after maintaining the condition for 12 hours.

As a result, Manila hemp was 38 g / m ² , and softwood pulp was 36 g / m ² , confirming that it had excellent humidity control performance in the middle humidity range.

<Paper making test of base paper layer 1>
Next, in the paper making process of the base paper layer 1, in order to search for conditions for the C—S—H powder to be supported on the humidity-controlling paper layer 2 with a high yield, particle size analysis of the C—S—H powder and fibers The fiber diameter of the material was measured.

  As a result, (1) the particle size of the C—S—H powder that did not leak from the base paper layer 1 was almost 1 μm or more, and (2) when 50% or more of Manila hemp fiber was blended, (3) In addition, when softwood pulp is used as an auxiliary material and hardwood pulp is blended at 10% or less, the papermaking property is good and the intertwined fibers It was confirmed that almost no gap of the C—S—H powder passed through.

<Relationship between mixing ratio of fiber material and moisture absorption in base paper layer 1 and humidity control paper layer 2>
Moreover, in order to confirm the optimal mixture ratio of the fiber material of the base paper layer 1 and the humidity control paper layer 2 and the C—S—H powder, the base paper layer 1 is made of Manila hemp pulp as a main raw material (dry weight). (The blend of 90% Manila hemp and 10% softwood pulp made by Howsand Co.), and the fibers that form the CSH powder carrying layer as the moisture conditioning paper layer 2 on the top are the same as the base paper layer 1 A papermaking test in which the ratio of the amount of fibers and the C—S—H powder is changed in a range of 20% to 100% as a blending ratio was performed using a natural polymer binder (manufactured by Yazawa Chemical Co., Ltd. “ "Magic glue"). Moreover, about each test body of thickness 3.5mm which dried these, the moisture absorption amount in the intermediate humidity range (relative humidity 50%-75%) was implemented.

  In addition, the moisture-conditioned Japanese paper test body obtained by the above method was subjected to water repellent treatment by a roller coating method using a water-based silicone water repellent, and these were also in a medium humidity range (relative humidity 50% to 75%). Measurement of the amount of moisture absorption was performed.

  Specifically, a measurement sample cut out to the size of A4 plate was equilibrated in a constant temperature and humidity chamber of 23 ° C. and 50% RH for 12 hours, and then changed to 75% RH. The weight after holding for a time was measured, and the amount of moisture absorption was calculated from the weight change and the sample area. The evaluation results are shown below.

As a result of the correlation analysis of the data in [Table 1], a strong positive correlation was confirmed between the fiber blending amount and the moisture absorption amount in the middle humidity region, and when the relative humidity was changed from 50% to 75% from the approximate expression, In order to satisfy the certification standard as a humidity control building material that needs to absorb moisture of 29 g / m ² or more within 12 hours, the total dry weight of the humidity control Japanese paper made of fiber material and C—S—H powder is about 1 m ^2. In the case of 1 kg, it was found that the blending ratio of the pulp requires 29% or more by internal division.

  In addition, the water repellent treatment can apply the water repellent uniformly in the form of dots by the roller coating method, so it has little effect on the hygroscopic performance and the performance degradation rate is only 17-18%. did it.

<Performance comparison of CSH powder and natural polymer binder>
Next, by comparing the prior art and the three samples 1 to 3 of the present invention, the effect of the difference in the inorganic porous material and the binder material on the humidity control performance in the middle humidity region of the sheet material will be verified. First, in the paper making test, No. Based on the blending ratio of 4 (pulp blending ratio 50%), a sheet-like “present invention sample 1” was prepared in the same manner, and the moisture absorption / release characteristics were measured.

  In addition, in order to verify the difference in the binder material and the humidity control performance, the C—S—H powder is used as it is for the inorganic porous material, and “Vinyl Blanc TO” manufactured by Nissin Chemical Industry Co., Ltd. is used as the binder material. -453N "(acrylic main component, glass transition temperature -26 ° C, active ingredient 48.7%) was used to prepare a sheet of" Invention Sample 2 ", and the moisture absorption and desorption characteristics were measured.

  Furthermore, in order to verify the difference in inorganic porous materials and humidity control performance, natural binder is used as the binder, and synthetic porous zeolite (A-type zeolite) is used as the inorganic porous material. Using “Molecular Sieve 4A”, a sheet of “Invention Sample 3” was prepared and its moisture absorption / release characteristics were measured.

  Specifically, each sample was equilibrated in a constant temperature and humidity chamber at 23 ° C. and 50% RH for 12 hours, then changed to 75% RH, and the moisture absorption after 12 hours was measured. After returning to 50% RH again, the moisture release amount after 12 hours was measured. The measurement results are shown below.

  From the above [Table 2], in order to obtain high humidity control performance in the medium humidity range, the sheet material should use C—S—H powder for the inorganic porous material, and use a natural polymer binder as the binder material. Was confirmed to be preferable.

<Flame retardancy evaluation test>
Next, since the interior wall material is also required to have flame retardancy, whether or not it meets the standard, a combustion test was performed on the fiber material and the C-S-H powder blending ratio changed. .

  As a method for evaluating the flame retardancy, an adhesive for wallpaper (trade name “Wall Bond 100”, manufactured by Yazawa Chemical Industry Co., Ltd.) was applied to a 9.5 mm thick gypsum board and dried. A lighter flame was applied for 1 minute at an angle of 45 degrees to observe the spread of the flame for comparison. The evaluation results are shown below.

  Each blending ratio of natural pulp and C—S—H shown in [Table 3] above also imparted flame retardancy to the sheet, and the effect was good even with a 25% blend.

<Moisture absorption / release performance test>
In the above flame retardant measurement test, the results were good. FIG. 2 shows the results of measuring the moisture absorption and desorption performance of the water-repellent moisture-conditioned Japanese paper produced under the papermaking conditions of No. 5 (mixing ratio natural pulp: C—S—H = 75: 25).

According to this graph, it can be seen that the product of the present invention has a moisture absorption amount that exceeds the standard of the moisture absorption amount of 29 g / m ² , which is a certification standard as a humidity control building material.

  The present invention is generally configured as described above. However, the present invention is not limited to the illustrated embodiment, and various modifications can be made within the description of “Claims”. The weight ratio of each main raw material and auxiliary raw material of the layer 1, the humidity control paper layer 2, and the decorative paper layer 3 and the material used can be changed according to the desired moisture absorption performance.

  Moreover, the ratio of the thickness of each layer of the base paper layer 1, the humidity control paper layer 2, and the decorative paper layer 3 is not limited to 1: 3: 1, and can be changed to various ratios. It belongs to the technical scope of the present invention.

It is a fracture perspective view showing the structure of the humidity control Japanese paper sheet material of the embodiment of the present invention. It is the graph which showed the moisture absorption / release performance of this invention goods.

Explanation of symbols

1 base paper layer 2 humidity control paper layer 3 decorative paper layer

Claims (12)

Hemp fiber material, which is the main raw material, is mixed with natural fiber material, which is approximately the same diameter as this, and has good entanglement, and the average fiber is higher than these hemp fiber material and natural fiber material. A base paper layer 1 made by adding a fiber material having a small diameter and average fiber length as a gap adjusting fiber material;
Silicic acid having a predetermined particle size which is made into a layered state on the base paper layer 1 and is impervious to the fiber gaps of the base paper layer 1 with respect to the main hemp fiber material and the auxiliary natural fiber material. A humidity control paper layer 2 mixed with calcium hydrate (C—S—H) powder;
The humidity control paper layer 2 is formed in a layered state, and a breathable decorative paper layer 3 having a water-repellent finish on the surface is laminated and integrally formed. Characteristic water-repellent harmonic wet Japanese paper sheet.   The water repellent high-humidity Japanese paper sheet material according to claim 1, wherein the hemp fiber material of the base paper layer 1 is contained in a dry weight ratio of at least 50% or more.   The moisture conditioning paper layer 2 has a dry weight ratio of C-S-H powder of 25 to 70%, and a natural pulp fiber composed of hemp fiber material, softwood pulp fiber and hardwood pulp fiber is at least a dry weight ratio of 30% or more The water repellent high-humidity Japanese paper sheet material according to claim 1, wherein the water-repellent high-humidity Japanese paper sheet material is contained and bonded with a natural polymer binder.   The decorative paper layer 3 is formed by mixing and making 80 to 90% of hemp fiber material and 10 to 20% of a dry weight ratio of fibers composed mainly of softwood pulp in a dry weight ratio. The water repellent harmonic moisture Japanese paper sheet material as described in any one of -3.   5. The water-repellent high-humidity Japanese paper sheet according to claim 1, wherein a water-repellent agent is attached to the top of the uneven surface of the decorative paper layer 3. Wood.   The C—S—H powder of the humidity-controlling paper layer 2 has a particle size of 1 μm or more and is subjected to heat dehydration treatment. Aqueous high-humidity Japanese paper sheet material.   The water repellent high-humidity Japanese paper sheet material according to any one of claims 1 to 6, wherein the hemp fiber material of the main raw material in the base paper layer 1 and the humidity control paper layer 2 is Manila hemp fiber.   The water-repellent high-humidity humidified Japanese paper sheet material according to any one of claims 1 to 7, wherein the natural fiber material of the auxiliary material in the base paper layer 1 and the humidity control paper layer 2 is a softwood pulp fiber.   The water repellent high-humidity Japanese paper sheet material according to any one of claims 1 to 8, wherein the gap adjusting fiber material in the base paper layer 1 is hardwood pulp fiber.   The vegetable binder material which consists of a natural polymer, respectively is mixed with the base paper layer 1, the humidity-control paper layer 2, and the decorative paper layer 3, Each of Claim 1-9 characterized by the above-mentioned. Water repellent high-quality moisture Japanese paper sheet material.   The water-repellent harmonic moisture Japanese paper sheet material according to any one of claims 1 to 10, wherein a main raw material of the decorative paper layer 3 is hemp fiber material.   A hemp fiber material is used as a main raw material, and a natural fiber material having substantially the same diameter as this and having good entanglement properties is used as a secondary raw material, and is dispersed and mixed in water together with a vegetable binder. A fiber material having a smaller average fiber diameter and average fiber length than the fiber material and natural fiber material is added as a gap adjusting fiber material to prepare a base material liquid, and each of the fibers is included from the base material liquid After the base paper layer is cut off, before the base paper layer thus picked up is dried, the base material layer contains a hemp fiber material as a main material and a natural fiber material as a sub raw material. The humidity-controlling paper layer prepared by mixing calcium silicate hydrate (CSH) powder of a predetermined particle size that is impervious to the fiber gaps of the paperboard layer is layered to form a humidity-controlling paper layer. And then, before the base paper layer and the humidity control paper layer are dried, on the humidity control paper layer, it is made of a paper fiber material. A water-repellent, high-humidity Japanese paper sheet, wherein paper fiber is made from a liquid, and a decorative paper layer is formed and dried, and then the surface of the decorative paper layer is subjected to a water-repellent treatment. A method of manufacturing the material.

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