JPH0669901B2 - Hydraulic inorganic papermaking product and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION A. Technical Field of the Invention The present invention relates to a hydraulic inorganic papermaking product which is essentially excellent in mechanical performance without using asbestos, and a production method for obtaining such a papermaking product. It is about.

B Conventional Technology and Problems Thereof A hydraulic inorganic papermaking product is a composite mainly composed of fibrous material such as asbestos and hydraulic material such as cement as represented by an asbestos straight board.

Its main production method is to prepare a fiber component such as asbestos and a hydraulic binding component such as cement together with other additives in an amount of 5 to 30% by weight of an aqueous dispersion (papermaking slurry), and then use this on a round net or a Fourdrinier. It is a wet papermaking method in which the product is obtained by making it into paper, dehydration, molding, curing and drying.

This method provides inexpensive, high-strength, non-combustible materials with high productivity with simple equipment, and such products are widely used as building materials in a wide range of fields.

The role of asbestos in such hydraulic inorganic papermaking products is (1) the effect of imparting high productivity in the papermaking process (a) imparting uniform dispersibility of the fibers used in combination (b) particulates mainly composed of hydraulic substances Capturing substances and imparting appropriate aqueous properties (c) Prevention of delamination on the making rolls and molding rolls, wrinkles, and water cracking (d) Surface smoothness, imparting moldability during press molding (e) Green sheet (2) Securing physical properties of products (reinforcement of hydraulic materials) (a) Improvement of mechanical properties such as bending, pulling and impact strength (b) Addition of dimensional stability (c) It is said to improve durability. Furthermore, the characteristics inherent to hydraulic materials such as non-combustibility are hardly reduced. In addition, it is a very inexpensive substance.

As described above, the role of asbestos in the inorganic papermaking product is extremely important, which is why it is said that an inexpensive product having excellent physical properties cannot exist without the presence of asbestos.

Asbestos's excellent properties are that it is a fibrillar substance, has a high affinity with hydraulic substances, high strength, high Young's modulus, inorganic fiber, high water retention, etc. caused by.

On the other hand, asbestos generates dust in the air when manufacturing, processing, and constructing a product containing the asbestos.

In recent years, it has been revealed that when fine dust of asbestos is inhaled into the human body, it causes lung cancer, and its use gradually begins to be restricted by laws and regulations, and there is even a sign that the use is prohibited.

Furthermore, asbestos-producing countries are unevenly distributed in specific countries, and there is also the problem of resource depletion.

Under such circumstances, it is strongly desired to provide a hydraulic inorganic papermaking product which has a high productivity and high performance equivalent to that when using asbestos without including asbestos instead of a hydraulic inorganic papermaking product containing a large amount of asbestos. .

Conventionally, attempts have been made to produce products by a wet papermaking method by substituting asbestos with other substances, but they are not sufficient and are used only for very limited applications.

The reason is that as described above, there is no substitute that satisfies the excellent hydraulic substance trapping property of asbestos, the prevention of delamination, the imparting of moldability, and the excellent reinforcing property.

JP-A-55-121947 and JP-A-55-121948 disclose the dispersibility of glass fiber by combining pulp, a flocculant, and glass fiber.
Although it is an alternative to asbestos by improving the trapping property of hydraulic substances, the dispersibility and the trapping property are insufficient. Especially, regarding the trapping property, although the effect of the collecting agent can be seen, it is at most 70
The yield is about%, which is a problem in operational production. Furthermore, problems such as delamination have not been solved.

Japanese Patent Publication No. 57-60315 discloses a technique in which pulp and a relatively thin fiber (for example, rock wool) are used to improve the trapping property of a hydraulic substance, and an alkali glass fiber is used to enhance the physical properties of the product.

This technique also has an insufficient trapping property for hydraulic substances, and has a serious problem of delamination and moldability. Further, since the alkali glass fiber has poor dispersibility, the reinforcing effect is insufficient and the surface property of the product is also poor.

JP-A-55-144466 discloses a method for producing a fiber-reinforced cementitious product comprising synthetic inorganic fibers, natural organic fibers, and fine particles of particles smaller than cement particles, but the cement trapping ability is insufficient. In addition, sufficient reinforcement cannot be obtained only from natural organic fibers typified by pulp and synthetic inorganic fibers typified by rock wool.

Further, the durability which is most required for cement products is a problem only with the combination of rock wool having no alkali resistance and pulp which easily deteriorates.

European Patent Application Publication No. 0,0068,741AI has 5
~ 15% bulk pulp, 30-40% silica, 0.05-1%
There is disclosed a technique for obtaining a board by subjecting an autoclave to curing with the reinforcing fiber and the remaining cement. Although such a technique is mainly based on pulp, it has a problem in papermaking such as yield of cement, and also has a problem in durability.

British Patent Application Publication No. 2,101,645A contains 5-15
Of a large amount of pulp, ultrafine silica highly reactive with 5 to 40% calcium hydroxide, rock wool, glass fiber, and reinforcing fiber such as polypropylene are disclosed. High pressure autoclave curing is required to react ordinary silica and calcium hydroxide,
An example thereof is the above-mentioned European publication application 0,068,741AI, which is filed by the same applicant as the British publication application. The silica of the UK published application is one that reacts under normal pressure, but as a means thereof, it is a very special one in which the surface area is remarkably increased by forming ultrafine particles, and there is a problem in papermaking properties such as cement yield, and Since it is mainly composed of a large amount of pulp, there is a problem in durability.

None of the above-mentioned known techniques is sufficient to substitute asbestos having various excellent properties as described above, and far falls short of high productivity when using asbestos and excellent product physical properties.

In order to substitute the asbestos having such excellent properties, the present inventors consider that the point is to combine various components and bring out a synergistic effect in addition to the respective properties. -131451 invention is proposed. However, the dispersibility of fibrous substances, the ability to capture cement and the like, the property of preventing delamination, the surface property, the moldability, etc. are somewhat insufficient, and the present invention is the result of research conducted with an emphasis on improving these properties.

C Structure of the Invention The gist of the present invention is to disperse (c) a reinforcing fiber and (d) a fibrous inorganic substance in a dispersion liquid of (a) the inorganic powder and (b) pulp specified in the present invention, (E) A hydraulic inorganic papermaking product obtained by making a papermaking slurry by adding a hydraulic inorganic substance such as cement, and (f) making a papermaking product while adding a suspicious agent, and a method for producing the same.

The feature of the present invention is to provide a hydraulic inorganic papermaking product which has the same or higher high productivity as that of using asbestos without using asbestos at all, and whose physical properties are almost the same as those of the product containing asbestos. It is possible and can be achieved for the first time by combining the components of the species.

That is, the dispersibility of the reinforcing fibers and the like is improved by the action of the pulp and the inorganic powder, and the particles of the cement and the like are further produced by the interaction of the hydraulic substance such as the pulp, the inorganic powder, the fibrous inorganic substance, the collecting agent, and the cement. Of sheet-like materials, further preventing peeling between laminated sheets, and significantly improving paper-making properties such as handling properties of corrugated green board, etc. In addition, physical properties of the board material by reinforcing fibers in a good dispersed state Is significantly improved.

D Detailed Description of the Invention The first problem of wet papermaking products in an asbestos-free system is poor dispersion of fibrous materials such as reinforcing fibers.

Such dispersibility is significantly improved only by using the specified inorganic powders of the present invention in a specified manner.

That is, an average particle diameter of 2 × 10 ⁻³ to 1 × 10 5 is obtained by dispersing a pulp, which is a constituent component of the present invention, in an aqueous dispersion in which the pulp has a concentration of 1 to 5% by weight based on the total solid content of the papermaking slurry. ^After adding 2 to 20% by weight of the inorganic powder of ⁴ mm or adding pulp to the dispersion of the inorganic powder, an aqueous dispersion is prepared by stirring with a pulper or the like to prepare the aqueous dispersion. In this method, the reinforcing fiber and the fibrous inorganic substance of the constituents of the present invention are added, and the mixture is stirred and dispersed, and then a predetermined amount of the hydraulic inorganic substance is added to obtain a papermaking slurry.

Satisfactory dispersibility can be obtained only by adding reinforcing fibers or the like to an aqueous dispersion of such inorganic powder and pulp. Inorganic powder and pulp may be used alone or an aqueous dispersion of reinforcing fibers or the like. Satisfactory results cannot be obtained even if inorganic powder and pulp are added.

The second problem in the production of wet papermaking products in a system without asbestos is the trapping property of hydraulic inorganic substances such as cement and other particulate substances as described above.

Further, in the case of winding and laminating on a making roll, there is a problem that a crack phenomenon when developing into a sheet after cutting, delamination between laminated sheets, moldability such as corrugation, and surface smoothness are poor.

The capture rate of solids in the papermaking slurry must be 85% or more, preferably 90% or more. The various problems are such that the inorganic powder having an average particle size of 1 × 10 ⁻² to 1 × 10 ⁻⁴ mm is 2 to 20% by weight, pulp 1 to 5% by weight, and fibers other than asbestos with respect to the solid content of the papermaking slurry. It has been found that a satisfactory solution can only be achieved with a combination of 0.5 to 10% by weight of particulate inorganic material and 50 to 500 ppm of flocculant with respect to the hydraulic inorganic material. In particular, when an inorganic powder having an average particle size of 1 × 10 ⁻³ to 1 × 10 ⁻⁴ mm is used, as will be apparent from the examples described later, an extremely excellent capture rate can be obtained.

The inorganic powder of the present invention may be any inorganic substance as long as it is poorly soluble in water and has an average particle size of 2 × 10 ⁻³ to 1 × 10 ⁻⁴ mm.

Typical examples are natural or synthetic carbonates. For example, there are calcium carbonate, basic magnesium carbonate, dolomite, etc. such as natural limestone, heavy calcium carbonate, and synthetic light carbon.

Further, inorganic substances containing silicon dioxide are also suitable examples. Typical examples are granular minerals such as kaolin, clay, ball clay, and wax clay. Further, there are diatomaceous earth and silica stone powder, and synthetic water-containing or anhydrous silicic acid, silica dust as industrial waste, silica chrome, coal ash, fly ash, etc. are also included.

In addition, fine alumina powder, shavings and chopped rock can be used.

The above is one example, and the present invention is not limited to this. It is important that the average particle size of such an inorganic substance is 2 × 10 ⁻³ to 1 × 10 ⁻⁴ mm. If it exceeds 2 × 10 ^-3 mm, it does not contribute to the improvement of the dispersibility of the fibrous material, the capturing property of cement, etc. is deteriorated, and the moldability is deteriorated due to the generation of small cracks.
On the other hand, if it is less than 1 × 10 ^-4 mm, the effect is slightly lowered and it is not economically preferable. Average particle size is 2 × 10 for both natural and synthetic products
If it is ^-3 mm or more, crush it appropriately and use it within the specified range. The compounding amount is 2 to the solid content of the papermaking slurry.
Must be 20% by weight. If it is less than 2% by weight, there is no effect, and if it is more than 20% by weight, the trapping property of cement and the like is good, but delamination occurs and moldability deteriorates, which is not preferable.

The pulp content in the present invention must be 1 to 5% by weight based on the solid content of the papermaking slurry. If it is less than 1% by weight, the trapping property of particulate matter is lowered, and if it is more than 5% by weight, the flame retardancy of the product is impaired and delamination is increased, which is not preferable.

The type of pulp may be natural pulp or synthetic pulp. As the natural pulp, unbleached or bleached pulp from softwood or hardwood is mainly used, but pulp obtained from straw, bamboo, cotton, hemp, ramie, kozo, mitsumata or the like can also be used. Also, recovered dead paper obtained from newspapers, paper bags, cardboard boxes, etc. can be used.

The Canadian freeness is preferably 30 to 750 ml, more preferably 50 to 300 ml.

As synthetic pulp, polyolefin pulp, such as SW
P (polyethylene-based pulp manufactured by Mitsui Zerapack) and polyaramid-based pulp, such as Kevlar pulp (manufactured by Deyupon)
Can be used, and any fibrillar substance having a shape similar to these can be used.

The fibrous inorganic substance in the present invention has a thickness of 3 to 15 μm.
m, length 0.1 to 10 mm, other than asbestos may be natural or man-made.

As the artificial fibrous inorganic substance, there are glass fibers such as general A glass and E glass fiber, and alkali resistant glass fibers to which zirconium oxide is added, and further, shirasu fiber, slag wool, rock wool, ceramic fiber, etc. Can also be used, or two or more kinds of the fibers and the like can be used in combination.

Such a fibrous inorganic substance is particularly effective in improving the ability to capture a particulate substance such as cement at the time of paper making due to a synergistic action with other substances, and the longer the effect, the greater the effect.
Therefore, the length of the fibrous inorganic substance is the length when the paper is made,
That is, it means the length of the product width, not the length of the raw material. Even if the length of the raw material is 10 mm or more, it may be broken by a mixer, pulper, cheest, etc., and 60% or more may be 0.1 to 10 mm, preferably 1 to 5 mm. The diameter of the fiber is 3 in terms of diameter
If it is less than μ, it is said that the water quality is abnormally deteriorated and it is not good for the health. There is no effect at 15μ or more. The blending amount is 0.5 to 10% by weight, preferably 1 to 5% by weight, based on the solid content of the papermaking slurry. If it is less than 0.5%, the effect is poor, and if it is more than 10% by weight, the green sheet becomes too hard and the creeping property to the making roll is poor, and cracks and delamination easily occur when developing into a sheet shape. The moldability is also poor.

The coagulant may be a common coagulant. Organic, inorganic, or anionic, nonionic, cationic, or ionic ones may be used, but anionic polymer flocculants generally used as cement cements are preferably used.

The amount of the flocculant used is preferably 50 to 500 ppm with respect to the hydraulic inorganic substance. If it is less than 50 ppm, the effect is poor, and if it exceeds 500 ppm, the gathering power is too strong and the gathering body becomes a large block, or the water quality is too good to make a head difference, so it is difficult to make a uniform sheet. . In addition, it contaminates felt and results in loss of productivity.

As described above, the second problem in the production of a hydraulic wet papermaking product in a system without asbestos only by combining the specified inorganic powder, pulp, fibrous inorganic substance, and coagulant in the specified amounts, respectively. It is possible to solve the problems of insufficient trapping of the granular substance of the hydraulic inorganic substance, cracks when the sheet is spread from the making roll, delamination, moldability and surface property.

The reason for this is not clear, but it is considered that there is a synergistic effect in view of the surprisingly large effects that are expected from the effects of each of them.

Asbestos has the role of improving the paper-making property and reinforcing the product as described above. In the absence of asbestos, a combination of reinforcing fibers is generally required, and it is necessary to use known reinforcing fibers in the present invention.

Reinforcing fibers are the weak points of hydraulic inorganic cured products, such as tension,
Although it improves bending and impact strength, it is particularly important to improve tensile strength and bending strength. Fibers for that purpose must have tensile strength, high Young's modulus, good adhesion to hydraulic minerals such as cement, alkali resistance, harmless to health, and cheaper. Is desirable.

The most preferable reinforcing fiber satisfying the above conditions is a polyvinyl alcohol (hereinafter abbreviated as PVA) fiber, and a polyacrylonitrile fiber is also preferably used. These reinforcing fibers must have a tensile strength of 5 g or more per denier and a Young's modulus of 90 g or more per denier.

The compounding amount is 0.5 to 5% by weight with respect to the solid content of the papermaking slurry,
It should preferably be 1 to 3% by weight. If it is less than 0.5% by weight, there is no reinforcing effect, and if it exceeds 5% by weight, fractional defects occur and a uniform sheet cannot be obtained, and it becomes expensive.

Further, the fineness is preferably in the range of 0.1 to 20 denier.
The aspect ratio (ratio of fiber diameter to fiber length) is 200-150.
0 is a preferable range in consideration of both dispersibility and reinforcing property.

The hydraulic inorganic material that can be used in the present invention may be basically any hydraulic inorganic material, but a typical one is Portland cement. Portland cements include ordinary Portland cements, moderate heat Portland cements, early strength Portland cements, ultra early strength Portland cements, white Portland cements and sulfate resistant Portland cements. There are blast furnace cement, silica cement and fly-ash cement as mixed cement. Alumina cement, super rapid hardening cement, colloidal cement, and oil well cement as special cement are used. In addition, it is also possible to use semi-hydrated gypsum using gypsum, a mixed hydraulic material of hydrated gypsum and slag, magnesia and the like.

It is also possible to replace a part of the hydraulic inorganic substance with another substance depending on the purpose. For example, calcium sulphoaluminate type as an expansive admixture, perlite, shirasu balloon, other sepiolite, attapulgite, etc. as a weight reducing agent can be used.

E Effects and Uses of the Present Invention As described above, the present invention specifies the specified materials of the inorganic powder, pulp, polyvinyl alcohol-based or polyacrylonitrile-based reinforcing fiber, fibrous inorganic material other than asbestos, and suspicious agent, respectively. Providing a highly productive and high-performance asbestos-free hydraulic wet inorganic papermaking product by adding the effect of the synergistic effect between materials to each property by using in the method of and combining within a specific range. It was successful in doing.

F. Examples The present invention will be described below with reference to examples.

Example-1 Kaolin having an average diameter of 2 × 10 ⁻³ mm and Canadian freeness 100 ml of NUKP (unbleached softwood pulp) were added to a pulper with a slurry in white water to give a concentration of about 2% of 10
Stir for minutes.

After that, slag wool having an average diameter of 4 μm which is a fibrous inorganic substance and PVA fiber which is a reinforcing fiber are added at the same time and stirred for 2 minutes.

The slag wool was put in a pulper in advance, added with siaer, and then sieved to 0.5-2 mm.

The PVA fiber used had a fineness of 1.4 denier, strength of 12.8 g / dr (dr stands for denier), Young's modulus of 300 d / dr, and fiber length of 4 mm.

Portland cement, which is a hydraulic substance, was added to the aqueous dispersion, stirred for 5 minutes, and then transferred to Tiesto,
120 g / papermaking slurry was prepared.

The slurry for papermaking was introduced into a papermaking tank (bat) while adding an anionic scavenger (1K Flock T-210 from Iorikawa Kori) and a required amount of white water, and was made up on a 60 mesh circular net, Wind it up on the making roller and cut the raw plate into 50 pieces.
It was pressure molded at kg / cm ² . The curing conditions were heating at 50 ° C. for 24 hours, and then left in an air-dried state for 4 weeks.

The compounding amount and data are shown in Table 1. The dispersibility shown in the table means the dispersion state of the fibrous substance, and when the papermaking slurry is made into a net, the unevenness on the net is observed and the dispersion is very good. The state is ◎, the poor dispersion state with a lot of unevenness is ×, and the interval is 2
The rank was divided into ◯ and △. Butt water level is ◎ when it is possible to make a sufficiently uniform sheet, and when the water level is hardly taken and only a uniform sheet can be made, or when the water is too bad and the papermaking slurry exceeds the papermaking slurry, the The middle rank was evaluated qualitatively as ◯ and △. The capture rate (%) of Portland cement, etc. is determined from the slurry concentration (W ₁ ) before paper making in the paper making tank and the wastewater concentration (W ₂ ) discharged through the gauze. Sought as. The delamination property was qualitatively determined by manually delaminating the green plate after the making roll.
A state in which the layers are not clear even when a force is applied in the peeling direction and peeling is difficult is indicated by ⊚, a state in which peeling is easily performed is indicated by ×, and the space between them is divided into two ranks and is indicated by ◯ and Δ.

Regarding the cracks at the time of molding, the raw plate after the making roll was subjected to ordinary corrugation and the cracked state was observed.

The bending strength was measured according to JIS A 1408 "Bending test method for building boards", and shown as an average value in the vertical and horizontal directions.
Since the compounding amount of the reinforcing fiber changes substantially when the trapping property of the hydraulic material or the like changes, the yield-corrected bending strength is shown to compare the true reinforcing property.

The impact strength was measured by the Izod test method of JIS K-7110 only in the longitudinal direction without notching.

Comparative Examples-1 to 5 The compounding amounts and the measurement data are shown in Table-1.
1 to 4 are cases in which any one of the five components other than the hydraulic substance out of the substances constituting the present invention was missing.

Reference Example-1 An asbestos board having a compounding composition consisting of asbestos 6D 13%, unbeaten NUKP 2%, and the balance Portland cement was made by the same paper making machine as in Example-1, and used as a reference example.

From Table-1, it is obvious that Example-1 has excellent paper-making properties and physical properties as compared with Comparative Examples, and is equal to or higher than Reference Example-1 using asbestos.

On the contrary, if even one of the constituent elements of the present invention is lacking, it is not possible to obtain papermaking properties and physical properties comparable to asbestos.

Examples-2 to 3; Comparative Examples-6 to 7 250 ml of canadien freeness of NUKP in Example-1
In addition, the compounding amount was 1.5% (Example-2), 4% (Example-3), 0.5% (Comparative example-6), 10% (Comparative example-7).
Table 2 summarizes the results of papermaking by the same method as in Example 1 except for the above.

The examples all have satisfactory results, but the comparative examples have some problems. Comparative Example-7, which contains a large amount of pulp, is not preferable because the dimensional stability, which is a characteristic of the hydraulic inorganic plate, is extremely poor.

Examples-4 to 5; Comparative Examples-8 to 9 The compounding amount of the slag wool in Example-1 was 4% (Example-
4), 9% (Example-5), 0.2% (Comparative Example-8), 13
Table 3 shows the results of papermaking according to Example-1 except that the percentage was set to (Comparative Example-9).

In Comparative Example-8, the PVA-based fibers were poorly dispersed, the reinforcing property was lowered, and the capturing property of Portland cement etc. was unsatisfactory. In Comparative Example-9, the green plate is hard and delamination occurs, resulting in poor moldability. Also, when it was developed into a sheet from a making roll, it exhibited a cracking phenomenon.

Example-6; Comparative example-10 Changing the pulverization degree of kaolin in Example-1 to 1 × 10 ^-3 mm
(Example-6) Papermaking was carried out by the same method as in Example-1 except that 2 x ^10-2 mm (Comparative Example-10) was used. The results are summarized in Table-4. The results of Example 1 are also shown in the table.

When the average particle diameter is larger than the range of the present invention, dispersibility and portland cement capturing ability are deteriorated, and moldability and the like are deteriorated.

Example-7; Comparative Example-11 Papermaking was carried out in the same manner as in Example-1, except that kaolin was replaced with heavy coal (Example-7).

Papermaking was carried out by the same method as in Example-7, except that the addition time of heavy carbon was added at the same time as Portland cement in Example-7 (Comparative Example-11). The respective results are shown in Table-5.

When calcium carbonate is added according to the method of Example, the dispersibility of the PVA fiber is good, and as a result, the appearance and surface smoothness are good, and the reinforcing effect is large. Since the method of the comparative example cannot obtain sufficient dispersibility, the appearance and surface smoothness are poor and the reinforcing effect is poor.

G Use of the present invention The asbestos-free hydraulic inorganic papermaking product obtained according to the present invention can be used as a substitute for a conventional asbestos-containing product, but since it does not contain asbestos, its application is It can be expected to spread further.

To describe application examples, corrugated asbestos boards, roofing materials such as singles, asbestos-free flat boards, perlite boards, pulp cement boards, siding materials, curtain walls, fireproof partition walls, outer wall panels and other structures, ships, etc. There are interior and exterior materials or asbestos-free pipes.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI technical display location C04B 24:00) 2102-4G (72) Inventor Masaki Okazaki 1-2-2 Kaigandori, Okayama City, Okayama Prefecture No. 1 Kuraray Co., Ltd. (72) Inventor Sotaro Itaya 1-2-1 Kaigandori, Okayama City, Okayama Prefecture Kuraray Co., Ltd. (56) Reference JP-A-59-8653 (JP, A) JP-A-54 -99131 (JP, A) JP 54-136708 (JP, A) JP 50-147545 (JP, A) JP 55-100256 (JP, A) JP 51-62811 (JP, A) ) JP-B-57-42580 (JP, B2)

Claims (8)

[Claims] 1. An inorganic powder having an average particle diameter of 2 × 10 ⁻³ to 1 × 10 ⁻⁴ mm is 2 to 20% by weight based on the solid content of the papermaking slurry (hereinafter, referred to as% by weight based on the solid content of the papermaking slurry unless otherwise specified). ), 1-5% pulp, 0.5-5% polyvinyl alcohol-based or polyacrylonitrile-based reinforcing fibers, 0.5-10% fibrous inorganic substances except asbestos, and 50-500 pp flocculant.
m (hydraulic inorganic), the remainder is mainly hydraulic inorganic papermaking products. 2. The reinforcing fiber has a fineness of 0.1 to 20 denier, an aspect ratio of 200 to 1500, and a tensile strength of 5 g / denier or more,
Claim 1 whose Young's modulus is 90 g / denier or more.
The hydraulic inorganic papermaking product according to the item. 3. The hydraulic inorganic papermaking product according to claim 1, wherein the fibrous inorganic material has a diameter of 3 to 15 μm (equivalent to yen) and a length of 0.1 to 10 mm. 4. The Canadian freeness of pulp is 30 to 75.
The hydraulic inorganic papermaking product according to any one of claims 1 to 3, which has a volume of 0 ml. 5. An inorganic powder having an average diameter of 2 × 10 ⁻³ to 1 × 10 ⁻⁴ mm of 2 to 20% is added to a 1 to 5% pulp aqueous dispersion or a dispersion of the inorganic powder is added. 0.5 to 5% of polyvinyl alcohol-based or polyacrylonitrile-based reinforcing fibers and 0.5 to 10% of fibrous inorganic substances excluding asbestos are added to an aqueous dispersion in which pulp is added and stirred and dispersed, and the mixture is stirred and dispersed. A wet papermaking method for a hydraulic inorganic papermaking product, characterized in that a papermaking slurry prepared by adding the balance of hydraulic inorganic matter to the liquid is added while adding a coagulant of 50 to 500 ppm (to hydraulic inorganic matter). 6. The reinforcing fiber has a fineness of 0.1 to 20 denier, an aspect ratio of 200 to 1500, and a tensile strength of 5 g / denier or more,
Claim 5 whose Young's modulus is 90 g / denier or more.
A method for wet-making a hydraulic inorganic paper-making product according to the item. 7. A wet papermaking method for a hydraulic inorganic papermaking product according to claim 5, wherein the fibrous inorganic material has a diameter of 3 to 15 μm (equivalent to yen) and a length of 0.1 to 10 mm. 8. The Canadian freeness of pulp is 30 to 75.
It is 0 ml, The wet papermaking method of the hydraulic inorganic papermaking product in any one of Claims 5-7.