JPH0375501B2 - - Google Patents

Description

[Detailed description of the invention]

Industrial Application Fields The present invention has nailing properties (nail retention properties), water resistance, moisture resistance,
The present invention relates to a method for manufacturing mineral fiber boards that are excellent in heat resistance, heat insulation, processability, white appearance, discoloration resistance, etc., and are preferably used as interior and exterior building materials. Conventional technology In mineral fiber boards that are conventionally used as interior and exterior building materials and have nailing properties, moisture resistance, water resistance, etc., phenolic resin is used as a binder for mineral fibers in terms of performance such as moisture resistance and water resistance. It is also commonly used from a cost standpoint. Problems to be Solved by the Invention However, although these mineral fiber boards using phenolic resin as a binder have excellent moisture resistance, water resistance, and heat resistance, they have the brown to brown coloring characteristic of phenolic resin. It was not pleasing in terms of appearance.
Furthermore, if the surface is painted with white paint, condensation will occur inside the board due to high humidity conditions, and the condensed water will be colored by the phenol resin and bleed onto the surface, staining the painted surface. There were flaws. In particular, if this water becomes alkaline due to cement or the like used in the surrounding area, the coloring caused by the phenol resin becomes even more pronounced. Therefore, the object of the present invention is to provide mineral fibers that have excellent nailing properties, water resistance, moisture resistance, heat resistance, heat insulation properties, and processing suitability, have a white color that is desirable in appearance, and do not discolor even when condensation occurs. The present invention aims to provide a method for manufacturing a board. Means for Solving the Problems The present inventors have determined that the fiber component, which is mainly composed of mineral fibers and organic fibers and optionally contains an inorganic filler, is 85 to 94% by weight based on the total solid content and phenol. Mainly composed of white phenolic resin (resol type) mainly composed of methylene-bonded bisphenol A synthesized using triethylamine as a catalyst in an amount of 1 part by weight or less per 100 parts by weight of
5 to 14% by weight of the binder component, optionally containing hot water soluble or swellable natural or synthetic resins, based on the total solids content, and 0.05 to 3.5% of the binding aid, based on the total solids content.
A paper-made board obtained by suspending in water a mixture in which the total organic matter content is 20% by weight or less based on the total solids containing % by weight to obtain an aqueous slurry, and by paper-making and dewatering the obtained aqueous slurry. mold, dry,
When cured, it is possible to obtain a mineral fiber board with a specific gravity of 0.3 or higher that has excellent nailing properties, water resistance, moisture resistance, heat resistance, heat insulation properties, and processing suitability, as well as excellent white appearance and discoloration resistance. I found it. Therefore, the present invention provides (A) a fiber component mainly composed of mineral fibers and organic fibers in an amount of 85 to 94% by weight based on the total solid content, and (B) 5 to 14% by weight based on the total solid content. (C ) containing 0.05 to 3.5% by weight of a binding agent based on the total solid content, and the total organic matter content based on the total solid content is 20
A mixture of % by weight or less is suspended in water to obtain an aqueous slurry, and the obtained aqueous slurry is made into paper and dehydrated, and the obtained paper board is molded, dried, and hardened to produce a mineral fiber board with a specific gravity of 0.3 or more. A method of manufacturing a mineral fiber board is provided. Hereinafter, the method of the present invention will be specifically explained step by step. (A) Aqueous slurry preparation step (first step) In the present invention, first, a mixture consisting of a fiber component, a binder component, and a binding aid is suspended in water equivalent to 10 to 100 times the amount of the mixture. Solid concentration of components dispersed in water 1~
An aqueous slurry of about 8% by weight is obtained. The above-mentioned fiber components mainly consist of mineral fibers and organic fibers, and may optionally contain an inorganic filler, so these will be individually explained below. (1) Mineral fiber In the present invention, it is preferable to use granular cotton as the mineral fiber. Granular cotton, which is a mineral fiber, usually has an average fiber diameter of 3 to 7μ and a fiber length.
Particle size 5-50 consisting of single fibers of 30-40mm or less
It has a granular shape of about mm. The slurry obtained using such mineral fibers has excellent uniformity in the slurry due to the above-mentioned shape of the mineral fibers, and is characterized by having appropriate freeness especially during the paper-making process. On the other hand, when non-granular mineral fibers or glass fibers are used, there are disadvantages in that the slurry draining time in the papermaking process is too quick and poor dispersion occurs. (2) Organic fibers Organic fibers used in the present invention include pulps such as kraft pulp, recycled pulp, and waste paper pulp, as well as vinylon, poval, rayon,
Examples include natural or synthetic organic fibers such as cotton. In the method for producing a mineral fiber board of the present invention, the organic fiber component in the aqueous slurry acts as a bonding agent by enclosing the cross bonding points of the mineral fiber granular cotton, which is the other solid main component, and as a binder. In addition to developing the retention improvement effect of the white phenolic resin used, the organic fiber component itself also exhibits elasticity, reinforcing the mineral fiber granular cotton, and the resulting board has sufficient mechanical strength. It provides strength. (3) Inorganic fillers In addition to the mineral inorganic fibers and organic fibers mentioned above, calcium carbonate, clay, mica, and gypsum may be used depending on the purpose of surface smoothness, weight reduction, flame retardancy, cost reduction, fire prevention, etc. , talc, glass fine fibers, asbestos fine fibers, titanic acid, potassium fibers, aluminum hydroxide, antimony trioxide, vermiculite, attapulgite, sepiolite, silica powder, pearlite, shirasu balloons, and other inorganic fillers are optionally added. You can also. The ratio of these components (1), (2), and (3) to the total solid content forming the slurry is 85%, considering the lightness, flame retardance, and heat insulation properties of the board.
Limited to ~95% by weight. In addition, considering the retention of the binder during paper making, which will be described later, the total amount of organic fiber (2) and inorganic fine fiber in the inorganic filler (3) should be 3% by weight or more based on the total solid content. is preferred. Further, the amount of mineral inorganic fibers to be blended is preferably 50% by weight or more based on the total solid content, considering the light weight of the board. The binder component used together with the aforementioned fiber component in the present invention is mainly composed of a white phenolic resin, and may optionally contain a hot water soluble or swellable natural or synthetic resin. I will explain them individually. (4) White phenolic resin The white phenolic resin used in the present invention has the effect of imparting water resistance to the board, whitening the appearance of the board, and preventing discoloration. (a) Bisbuenol A alone or Phenol, within the range that does not impair whiteness,
1 mole of bisphenol A containing phenols such as cresol, xylenol, and P-alkylphenol, and aldehydes such as formalin and paraformaldehyde.
1.0 to 3.5 mol of triethylamine per 100 parts by weight of the bisphenols A.
A powdered methylene-bonded phenolic resin (resol type) with a particle size of 100 to 500 mesh obtained by condensation using less than parts by weight as a catalyst, and (b) phenolic hydroxyl groups of the phenolic resin of (a) above as necessary. is esterified or etherified with a compound having a carboxylic acid at the end or a compound having an epoxy group at the end, and optionally treated with ammonia or the like, and treated with methylol adjacent to the hydroxyl group.The particle size is 100~
This is a granular methylene-bonded phenolic resin (resol type) with a size of 500 mesh. The powdered phenolic resin utilized preferably has a particle size of 100 to 500 mesh. This is because coarse particles with a particle size of less than 100 mesh have poor dispersibility in the aqueous slurry that is the raw material for board making, resulting in poor performance as a binder and making it difficult to obtain a homogeneous board. Yes, again
This is because fine powders that pass through 500 meshes have drawbacks such as a large loss of flow into white water during the papermaking process. (5) Hot water soluble or swelling natural or synthetic resin In the present invention, hot water soluble or swelling resins include natural resins such as starches such as cornstarch and tapioca, vegetable gums such as guar gum and CMC, polyvinyl alcohol,
Synthetic resins such as acrylic emulsion and vinyl acetate emulsion can also be used as a binder together with the above-mentioned white phenolic resin. Although this natural or synthetic resin cannot impart good water resistance to the resulting board, it has advantages such as higher dry strength (normal strength) than phenolic resin and lower cost. The ratio of these components (4) and (5) to the total solid content forming the slurry is 5 to 15% by weight. The reason is that at less than 5% by weight,
Satisfactory board strength, water resistance, etc. cannot be obtained, and if the content exceeds 15% by weight, the retention of the binder during papermaking will deteriorate.
This is because there is no strength effect depending on the ratio of the added amount, and the resulting board cannot maintain a quasi-incombustible grade. The blending ratio of the white phenolic resin (4) and the hot water soluble or swellable natural or synthetic resin (5) is determined by the target water resistance of the final board, but generally the blending ratio is about 1:1. suitable. Since the aqueous slurry used in the present invention contains a binding aid as an essential component along with the above-mentioned fiber components and binder, the binding aid will be explained below. (6) Binding aid The binding aid is used in the paper-making process during the manufacturing process of mineral fiber board using the wet paper-making method. ) to the wet mat, and anionic or cationic flocculants, which are commonly used as bonding aids in the wet papermaking method of this type of mineral fiber board, are used. Ru. When an anionic flocculant is used as a binding aid, it is preferable to use sulfuric acid in order to enhance the flocculating effect of the flocculant.
For example, it is preferable to use polyacrylamide, which is an anionic flocculant, in an amount of about 0.05 to 1.5% by weight and sulfuric acid sodium chloride in an amount of about 0.1 to 2.0% by weight. In this case, the pH of the aqueous slurry that is the raw material for papermaking is
will be 4.5 to 6.8. Also, in this case, it is possible to add 2.0% by weight or more of sulfuric acid loam, but if an unnecessarily large amount of sulfuric acid loam is added, acid hydrolysis of the mineral fiber granular cotton will occur. Since this will reduce the strength of the resulting mineral fiber board, it is preferable to keep the amount of sulfuric acid sodium chloride added to 2% by weight or less. Furthermore, in the case of polymer flocculants, the amount added is 0.05% by weight to sufficiently exhibit the flocculating effect, and the amount of 0.8 to 1.2% by weight is the highest, but when the amount exceeds 1.5% by weight, the opposite effect occurs. Since a phenomenon occurs in which the flocs once flocculated are redispersed, the amount of polymeric flocculant added must be kept to a maximum of 1.5% by weight. In addition, in the above-mentioned mixture consisting of the fiber component, the binder component, and the binding aid, the total organic matter content must be 20% by weight or less so that the resulting board passes at least the quasi-nonflammable grade. (B) Paper board production process (second process) In the present invention, the aqueous slurry adjustment process (first process)
The aqueous slurry obtained in step) is formed and dehydrated using a fourdrinier type (fourdrinier type), circular net type (oliver type) or the like paper making machine, and a paper-made board is produced. (C) Paper board molding, drying, and curing process (third step) Furthermore, in the present invention, as the third and final step, after molding the obtained paper board, drying and curing are completed to achieve a specific gravity of 0.3 or more. Obtain mineral fiber board. The reason why the specific gravity of the mineral fiber board is limited to 0.3 or more is that if it is less than 0.3, the resulting board will not have normal strength, water resistance, nailing resistance, or sag resistance. In the above-mentioned method for manufacturing mineral fiber board by the wet paper forming method consisting of the first, second, and third steps, in the first step, as described above, the granular phenolic resin serving as the binder is but
By avoiding coarse materials that do not pass through the 100 mesh, the powdered phenolic resin is almost uniformly dispersed in the aqueous slurry that is formed, and since the powdered phenolic resin is water-insoluble, In the slurry formation process, the formation of mama powder,
It is possible to easily form an aqueous slurry without causing problems such as stickiness or increased viscosity, and the phenolic resin used as a binder does not adhere to raw material mixing tanks, piping, pumps, etc. It has the advantage of not contaminating the wire mesh. Further, in the second step, the paperboard manufacturing step, the drainage mechanism in this step has features as detailed below. In other words, an aqueous slurry in which the mineral fiber granular cotton, organic fibers, powdered phenolic resin, and binding aid are substantially uniformly dispersed in water in the above-mentioned specific proportions is obtained by dispersing the filtrate after papermaking. Sometimes, various materials other than powdered phenolic resin are combined and play the role of a filter, allowing the powdered phenolic resin to remain in the interstices of the fibers in a uniformly divided state, holding it in that position, and dehydrating almost only the water. It has the feature that the amount of the powdered resin flowing out into the white water at this time can be limited to about 1 to 3% of the input amount. The method for producing a mineral fiber board of the present invention has the above-mentioned structure, and has strength suitable for nailing, flame retardancy suitable for quasi-incombustibility, water resistance, moisture resistance, surface smoothness, and resistance. It has excellent breakability, dimensional stability, and suitability for machining such as sawing and sawing, and has a white appearance and discoloration resistance, making it suitable for use as interior and exterior wall materials, roof base materials, etc., and is literally white with high strength. It has the characteristic that a retardant insulation board can be obtained. Furthermore, since pulp can be used as one of the organic fibers in the solid main component, the production cost is low. Furthermore, the method for manufacturing a mineral fiber board of the present invention can be directly applied to an apparatus for manufacturing a mineral fiber board using a conventional wet papermaking method. As described above, the powdered phenolic resin can be reliably dispersed evenly in the wet mat without causing any contamination of the manufacturing equipment, and by using the raw mineral fiber granular cotton, organic fiber, and binding agent. This has the effect that the powdered phenolic resin can be retained and retained, and can be filtered with almost no leakage of the powdered phenolic resin into the filtered water. For this reason, in the method for manufacturing mineral fiber board of the present invention using the wet papermaking method, if the amount of raw materials used, adjustment conditions, etc. are set as specified, the papermaking speed etc. may be reduced or some of the material may enter the white water. The present invention has the effect of mass producing white high-strength fuel-resistant insulation boards without deteriorating the properties of the board as a product due to outflow of raw materials. Furthermore, in the method for manufacturing mineral fiber boards of the present invention, asbestos, which was considered indispensable in terms of retention and adhesion to organic binders when manufacturing mineral fiber boards using the conventional wet papermaking method, is completely removed. It has all of the above properties without being used, namely, flame retardancy, water resistance, moisture resistance, smooth surface, specified hardness, strength to prevent breakage, no warping or sag due to humidity, and dimensional stability. It is possible to mass produce white, high-strength, flame-retardant insulation board that has properties such as being able to be sawed and nailed on site, and thus reduces the rise in material costs associated with the use of asbestos. It has the action and effect of being able to simultaneously resolve the negative effects on health. Reference Examples and Examples The present invention will be further explained in detail with reference to Reference Examples and Examples below, but the present invention is not limited to these Reference Examples and Examples. Reference Example Four types of white phenolic resins were synthesized by the following method. White phenolic resin A 0.5 per mole of bisphenol A, 1 mole of 37% formalin and 100 parts by weight of bisphenol A in a three-necked flask with stirrer and condenser.
An aqueous solution containing a formulation consisting of parts by weight of triethylamine was prepared and condensed at 70°C for the first 60 minutes and at 100°C for the latter 120 minutes, dried, and subsequently ground in a ball mill to obtain particles with a particle size of 200-250 mesh. A white phenolic resin A was obtained. White phenolic resin B 1 mol of bisphenol A, 2.5 mol of 37% formalin, and 0.1 part by weight of triethylamine per 100 parts by weight of bisphenol A were used for the first half of 60
A condensation reaction was carried out in the same manner as in the synthesis of white phenolic resin A, except that the temperature was 70°C for 120 minutes and 90°C for the latter half of 120 minutes, to obtain powdery white phenolic resin B. White phenol resin C White phenol except that in the synthesis of white phenol resin B, brominated phenyl glycidyl ether was added at a ratio of 10 parts by weight to 100 parts by weight of bisphenol A to modify it 10 minutes before the condensation reaction was stopped. Powdered white phenol resin C was obtained in the same manner as in the synthesis of resin B. White phenolic resin D: 1 mole of bisphenol A, 1.5 moles of 37% formalin, and 0.1 part by weight of triethylamine per 100 parts by weight of bisphenol A, the temperature was 70°C for the first 90 minutes and 90°C for the second half 150 minutes. Powdered white phenolic resin D was obtained in the same manner as the synthesis of white phenolic resin A, except that 0.05 part by weight of 29% aqueous ammonia was further added in the latter half of the reaction. Examples 1 to 4 and Comparative Examples 1 to 3 Solid components (1000
An aqueous slurry is prepared using a 4% by weight aqueous dispersion of g), and the obtained aqueous slurry is made into paper using a test paper making machine in a laboratory and dehydrated, and the obtained paper board is then press formed using a press forming machine. The obtained press molded product was dried at 250℃ using a hot air dryer.
This was followed by drying and curing at 170°C for 1 hour to obtain mineral fiber boards with a white appearance in 16 different thicknesses of 12 mm depending on the specific gravity. Molding drainage time of aqueous slurry, dry specific gravity, bending strength, 2-hour water absorption strength of the obtained board,
Table 1 shows the 2-hour water absorption rate, nailing performance, flammability, appearance, and color fastness.

[Table] The method for measuring the molding drainage time and the physical properties of each board in Table 1 will be explained below. ●Formation and drainage time of aqueous slurry - The aqueous slurry is made of a wire mesh with a mesh size of 60 mesh, and the size of the wire mesh section.
450×450mm, depressurization degree of dehydration part during molding is 1500mm
The dewatering time during papermaking was measured using a water column test papermaking machine. ●Specific gravity and bending strength - Measured according to JIS A 6307. ●2-hour water absorption rate - The sample was immersed 30 cm below the water surface for 2 hours, then taken out, the surrounding water was gently wiped off, the weight was immediately measured, and the increased weight was divided by the original weight and multiplied by 100. . Sample size is 12×
It is 50×170mm. ●2-hour water absorption strength - The sample whose water absorption rate was measured was then measured in accordance with JIS A 6307. ●Nailability - We observed whether nails could be nailed into a wood base using normal methods and whether they could be firmly fixed. ●Flammability - Measured according to JIS A 1321. 1st
~ In Table 3, "quasi-nonflammable" has higher flame resistance than "flammable". ●Appearance - Evaluated by visual observation. ●Discoloration resistance - A test plate prepared by pouring a solution prepared to pH 13.5 (corresponding to the eluate from hardened cement) to a depth of 10 mm in a polyethylene container, then applying a general vinyl acetate-based white paint to this and drying it. Dip the bottom edge of the 24
Evaluate the degree of discoloration of the sucked up area after a period of time. As shown in Table 1, the boards of Examples 1 to 4 obtained by the method of the present invention are excellent in normal strength, water resistance, nailing performance, white appearance, and color fastness. In contrast, Comparative Example 1 in which the amount of binder used was less than 5% by weight.
The boards of Comparative Example 3 and 2 have poor normal strength, water resistance, and nailing properties, and the board of Comparative Example 3 with a total organic matter content of more than 20% by weight has a lower flame retardant grade.
Moreover, the appearance whiteness and discoloration resistance are also poor. Examples 5 to 10 An aqueous slurry was prepared using a 4% by weight aqueous dispersion of a solid component (1000 g) consisting of each of the composition components listed in Table 2 below, and from then on, the same procedure as in Example 1 was carried out.
A mineral fiber board was obtained in the same manner as in steps 4 to 4. Table 2 shows the physical properties of the mineral fiber board obtained.

【table】

[Table] The methods for measuring the molding drainage time and the physical properties of each board in Table 2 are as described above. As shown in Table 2, the boards of Examples 5 to 10 obtained by the method of the present invention were excellent in normal strength, water resistance, nailing performance, combustibility, white appearance, and color fastness. Examples 11-12 and Comparative Example 4 Three types of mineral fiber boards with different specific gravity were produced using solids having the same composition as that of Example 2. Comparative example 4 (specific gravity 0.25) smaller than specific gravity 0.3 is 2
The temporal water absorption rate is high, the bending strength and water absorption strength are insufficient, and the nailing performance is poor, resulting in quality problems as an interior/exterior building material, which is the object of the present invention. Table 3 shows the physical properties of the mineral fiber board obtained.

[Table] The methods for measuring the molding drainage time and the physical properties of each board in Table 3 are as described above. From Table 3, the boards of Examples 11 and 12 with a specific gravity of 0.3 or more gave excellent results in each physical property, whereas the boards of Comparative Example 4 with a specific gravity of less than 0.3 were bent due to the lack of specific gravity. Strength, water resistance (2
It was inferior in (hourly water absorption strength, 2-hour water absorption rate) and nailing performance (insufficient performance). Effects of the Invention As detailed above, according to the present invention, it has excellent nail driving performance (nail retention performance), water resistance, moisture resistance, heat resistance, heat insulation property, and processing suitability, and has a white color that is favorable in appearance. A mineral fiber board that does not become colored even when condensation occurs is obtained.

Claims (1)

[Scope of Claims] 1. (A) A fiber component mainly composed of mineral fibers and organic fibers in an amount of 85 to 94% by weight based on the total solid content, (B) 5 to 94% by weight based on the total solid content. A resin binder component mainly composed of a white phenolic resin mainly composed of methylene-bonded bisphenol A synthesized using 14% by weight of triethylamine in an amount of 1 part by weight or less per 100 parts by weight of phenols; C) 0.05 to 3.5% by weight of the total solids content of a binding agent, and the total organic matter content based on the total solid content is 20%.
A mixture of % by weight or less is suspended in water to obtain an aqueous slurry, and the obtained aqueous slurry is made into paper and dehydrated to form a paper-made boat, which is then dried and hardened to produce a mineral fiber board with a specific gravity of 0.3 or more. A method for manufacturing a mineral fiber board, characterized in that it obtains a mineral fiber board.