JPH0692707A - Inorganic hard material - Google Patents

Abstract

PURPOSE:To provide a low-cost inorg. hard material having excellent strength. CONSTITUTION:This inorg. hard material contains a base material consisting essentially of base powder contg. 12CaO.7Al2O3 and/or a solid soln. thereof and gamma-2CaO.SiO2 and 10-35 pts.wt. gypsum basing on 100 pts.wt. of the base powder, 1.0-10.0 pts.wt. glass fibers basing on 100 pts.wt. of the base material and 0.1-5.0 pts.wt. water-soluble paste basing on 100 pts.wt. of the base material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inorganic hard material, more specifically, 12CaO.7Al ₂ O ₃ or / and its solid solution and γ-2CaO. The present invention relates to an inexpensive inorganic hard material having excellent strength, which is made of an inorganic material containing SiO ₂ and gypsum as main components.

[0002]

2. Description of the Related Art A large amount of slag during the steelmaking reduction period is produced in a steelworks, and the material is used as a cement raw material.

As a cement using the steelmaking reduction period slag, "cement" using the steelmaking reduction period slag and gypsum generated as a by-product for sulfur oxide pollution control treatment (Japanese Patent Publication No. 62-47827). Gazette, Japanese Examined Patent Publication No. 62-50428) has been developed. Despite the fact that this cement uses the materials of steelmaking reduction slag and gypsum, its hardened material has physical properties (strength, etc.) similar to ordinary cement, and it has excellent early strength and is non-shrinkable. It has features and is put to practical use as a useful cement.

The cement described in Japanese Examined Patent Publication No. 62-47827 is 1 to 80 parts by weight of γ-2CaO.SiO ₂ and 1 to _2.
This is a fast-strength, white and inexpensive cement, which contains 100 parts by weight of a substrate powder containing 90 to 20 parts by weight of 2CaO · 7Al ₂ O ₃ and _{2 to} 1000 parts by weight of gypsum as main components.

The cement described in JP-B-62-50428 is γ-2CaO · SiO ₂ and 3CaO · 2S.
10 to 80 parts by weight of one or two kinds of iO ₂ · CaF ₂ and solid solution 90 to ₂ of 12CaO · 7Al ₂ O ₃ and CaF ₂ .
100 parts by weight of the substrate powder containing 0 parts by weight, and 1.0 to 1000 parts by weight of gypsum per 100 parts by weight of the substrate powder as main components, and the hardened material has physical properties (strength and the like) similar to those of ordinary cement. In addition, it is an inexpensive cement with excellent fastness and no shrinkage.

[0006]

However, although the above-mentioned cement consisting of steelmaking reduction slag and gypsum is useful as an inexpensive cement having excellent early strength, no shrinkage, and a hardened body having an appropriate strength, The characteristics of the material itself are that the density is in the range of 1.0 to 1.2 and the bending strength is 30 to 40 kg.
f / cm ² and strength characteristics are not always sufficient. Therefore,
Interior panels and tile panels that require high strength,
Furthermore, there is a problem that it cannot be applied when it is directly stretched and used as a sheet pile or the like that is directly incorporated into a building.

[0007] Therefore, the inventors of the present invention have earnestly studied to solve the problems of the prior art as described above, and as a result of various systematic experiments, the present invention has been accomplished.

(Object of the Invention) An object of the present invention is to provide an inexpensive inorganic hard material having excellent strength.

The present inventors have focused on the following points with respect to the above-mentioned problems of the prior art. That is, in the hardened body of the cement consisting of steelmaking reduction period slag and gypsum,
Ettringite, which is one of the constituents of the cured product, or calcium hydrate with high alumina is micron-order crystals as needle-like crystals. Therefore, the required strength cannot be obtained only with the material.

Therefore, in order to improve the strength of the inorganic hardened body using the special cement, glass fibers are mixed to improve the strength, a water-soluble sizing agent is mixed, and a base material made of the special cement is mixed with a specific composition. The present invention has been accomplished by paying attention to what is intended.

When ordinary Portland cement is used, even if glass fibers are mixed, the cement cannot be improved in strength because it is highly alkaline and corrodes the glass fibers. In addition, in order to improve bending strength. Had the problem of requiring autoclaving. Further, when alumina cement is used, there is a problem that strength deterioration occurs due to crystal transition of the cement itself even if glass fibers are mixed.

[0012]

The inorganic hard material of the present invention comprises:
12CaO · 7Al ₂ O ₃ or / and its solid solution and γ-
A substrate powder containing 2CaO.SiO ₂ and an inorganic hard material substrate containing, as main components, 10 to 35 parts by weight of gypsum per 100 parts by weight of the substrate powder, and the inorganic hard material substrate 1
It is characterized in that it comprises 1.0 to 10.0 parts by weight of glass fiber and 0.1 to 5.0 parts by weight of water-soluble sizing agent with respect to 00 parts by weight.

[0013]

The mechanism by which the inorganic hard material of the present invention exerts excellent effects is not always clear, but
It can be considered as follows.

The inorganic hard material of the present invention is γ-2CaO · S.
An inorganic hard material base material containing iO ₂ and 12CaO · 7Al ₂ O ₃ or / and its solid solution and gypsum as main components, and glass fiber are main components.

This γ-2CaO.SiO ₂ and 12CaO
When glass fibers and a water-soluble sizing agent are mixed in an inorganic hard material mainly composed of 7Al ₂ O ₃ or / and its solid solution and gypsum, the glass fibers are randomly dispersed and arranged in the gaps of the inorganic hard hydrate compound. It is considered that the water-soluble sizing agent binds both at the contact point of the compound and the glass fiber, and the strength is improved by dispersing and strengthening the glass fiber. From this, it is considered that an inorganic hard material having excellent strength can be obtained.

The amount of gypsum mixed is 10 to 35 parts by weight with respect to 100 parts by weight of the substrate powder. The mixing amount of this plaster is 1
When the amount is less than 0 parts by weight, 12 contained in the inorganic hard material substrate
CaO.7Al ₂ O ₃ remains unreacted, and alumina cement hydrate is formed, so that sufficient strength cannot be obtained. Further, when the amount of the mixture exceeds 35 parts by weight, unreacted gypsum is generated. However, there is a problem in that the water resistance is reduced as the amount increases.

The amount of the glass fiber mixed is 1.0 to 10.0 parts by weight with respect to 100 parts by weight of the inorganic hard material substrate. When the amount of this glass fiber mixed is less than 1.0 part by weight,
A sufficient reinforcing effect cannot be obtained and the strength is not sufficiently improved.
On the other hand, if the mixing amount exceeds 10.0 parts by weight, the moldability of the molded product deteriorates.

The amount of the water-soluble sizing agent mixed is 0.1 to 5.0 parts by weight based on 100 parts by weight of the inorganic hard material substrate. When the mixing amount is less than 0.1 part by weight, a sufficient adhesive effect cannot be obtained, and when the mixing amount exceeds 5.0 parts by weight,
Further adhesion effects cannot be obtained, resulting in high cost and inconvenience such as reduction in antibacterial effect.

Since the inorganic hard material base material of the present invention can be obtained at a low cost as a waste material such as steelmaking reduction slag and gypsum, and the glass fiber can be obtained at a low cost as glass fiber for FRP or the like, it is an inexpensive inorganic hard material. It can be a material.

[0020]

The inorganic hard material of the present invention has excellent strength and is inexpensive.

[0021]

The invention (concrete example) which is more specific than the above invention will be described below.

The inorganic hard material base material is 12CaO.7Al ₂
The main components are a substrate powder containing O ₃ or / and its solid solution and γ-2CaO · SiO _2, and 10 to 35 parts by weight of gypsum per 100 parts by weight of the substrate powder.
In addition, CaF ₂ and other components and impurities may be contained as long as the effects of the present invention are not impaired.

The inorganic hard material base material other than gypsum, that is, the substrate powder, is a main component of the steelmaking reduction slag, and should be obtained at low cost as slag powder which is naturally wind-broken or slag powder which is arbitrarily crushed. You can

The raw material for 12CaO.7Al ₂ O ₃ and / or its solid solution and γ-2CaO · SiO ₂ is C.
It is recommended that steelmaking reduction slag within a certain range of aO, SiO ₂ , and Al ₂ O ₃ be the most readily available. In particular, slag that causes dusting during cooling is suitable as a raw material. When ideal steelmaking slag is gradually cooled in air, γ-2CaO ・ SiO ₂ and 12CaO ・ 7
A matrix powder containing Al ₂ O ₃ as a main component is obtained. In addition, as other components, several% or less of glass component, M
gO, iron powder, etc. are included. In addition, minerals and slag may be blended so as to form the component to be used as a raw material, or may be synthesized by a melting process.

As gypsum, dihydrate gypsum or hemihydrate gypsum is preferably used. Of the dihydrate gypsum, desulfurized gypsum is a by-product generated in a thermal power plant or the like, and is suitable because it can be used in a powder form. Gypsum dihydrate is preferred because it rapidly reacts with 12CaO.7Al ₂ O ₃ or / and its solid solution in the substrate powder and does not allow the presence of hydrated compounds that change volume during transition. The gypsum dihydrate may be either a by-product such as desulfurized gypsum and phosphate gypsum or natural gypsum. Further, hemihydrate gypsum is suitable because it immediately changes to dihydrate gypsum upon hydration, and therefore, as with the above, there is no hydrated compound that changes in volume upon transition. In addition, anhydrous gypsum is CaO ・ Al ₂ O ₃
Since 10H ₂ O is easily formed, and the dimensional change of the hydrated cement component upon drying or water absorption is large on the order of 10 ^−3, it is necessary to use it considering the application.

The amount of gypsum mixed is 10 to 35 parts by weight with respect to 100 parts by weight of the substrate powder. Further, in the case of this example, the amount of gypsum mixed is preferably 12 to 25 parts by weight. . As a result, the effects of the present invention can be better exhibited. Further, the particle size is preferably 0.1 mm or less.

Glass fiber is a reinforcing material for an inorganic hard material base material. Specifically, commercially available glass fiber for FRP or the like is used. In addition, when PVA (polyvinyl alcohol) is coated on the surface of the glass fiber, the adhesiveness is further improved, which is preferable. The mixing amount of the glass fiber is 1.0 to 10.0 parts by weight with respect to 100 parts by weight of the inorganic hard material substrate, and the mixing amount of the glass fiber is 2.5 to
It is preferably 5.0 parts by weight. As a result, the bending ratio strength becomes 100 or more, and it is possible to obtain a unique effect that the strength can be made more excellent.

Further, the longer the glass fiber is, the more the pullout resistance at the time of breaking becomes large and the higher the strength is, but it is more preferable that the length is 12 to 35 mm. This is because the workability of the mortar can be improved by using the one having the length. Further, the thickness is not particularly limited, but it may be an appropriate thickness capable of expressing a desired strength depending on the use, but it is preferable to use glass fiber having no surface defects.

The water-soluble sizing agent is an additive for further strengthening the bonding state at the interface between the inorganic hard material substrate and the glass fiber, and specifically, soluble vinyl acetate powder, soluble polyvinyl alcohol, resin emulsion. Etc. The amount of the water-soluble sizing agent mixed is 100
The amount is 0.1 to 5.0 parts by weight with respect to parts by weight, and it is preferable that the amount of the water-soluble sizing agent is 1.0 to 2.5 parts by weight. As a result, for example, a material having a density of about 1.0 g / cm ³ and a bending ratio strength of about 100 or more can exhibit an excellent effect of improving hardness.

Further, additives such as a water retention agent, a weight-reducing extender, and a curing modifier can be added to the inorganic hard material of this example.

The water retention agent is an additive for suppressing the evaporation of water that reacts in the mortar, and specific examples thereof include cellulose compounds such as methyl cellulose, ethyl cellulose and carboxymethyl cellulose. The amount of the water retention agent mixed is preferably 0.1 to 5.0 parts by weight with respect to 100 parts by weight of the inorganic hard material substrate.
If the mixing amount is less than 0.1 part by weight, the effect of suppressing the evaporation of water may not be sufficiently obtained, and if the mixing amount exceeds 5.0 parts by weight, the inorganic hard material substrate may be used. There is a risk of slowing the curing of the.

The weight-reducing extender is an additive for reducing the weight of the inorganic hard material and improving the workability of the cement secondary product, and specifically, it is a needle such as perlite, leeche stone, or sepiolite. Resins such as crystallites, diatomaceous earth, foamed glass particles, foamed styrene and foamed urethane can be mentioned.

The curing modifier is an additive for adjusting the working time, and specific examples thereof include oxycarboxylic acids such as gluconic acid and salts thereof, and protein amino acids such as casein and peptone. The mixing amount of the curing modifier varies depending on the type of the additive, but in the case of gluconic acid, it is preferably 0.1 to 1.0 parts by weight with respect to 100 parts by weight of the inorganic hard material substrate. If the mixing amount is less than 0.1 parts by weight, the curing delay may not be sufficiently caused, and if the mixing amount exceeds 1.0 parts by weight, the curing may not be performed for a long time.

An example of the method for producing the inorganic hard material of this example will be specifically described. That is, a plaster such as desulfurized gypsum, PV
Mortar kneading water containing a water-soluble sizing agent such as A, slag for steelmaking reduction period, and glass fiber are sequentially added and mixed. During this time, it takes about 1 minute, but by further increasing the time for about 30 seconds, a lightweight mortar containing fine bubbles can be obtained. This is poured into a mold of an arbitrary shape, left at room temperature, or cured with steam at about 40 ° C. to obtain an inorganic hard material having a predetermined shape such as a plate material. In this case, if a weight-reducing bulking agent such as perlite is mixed with the desulfurized gypsum, air bubbles are easily mixed. When the shape is plate-like, it is preferable to roll with a roller or the like.

The inorganic hard material of this example has the advantages of higher strength and higher absorption of breaking energy than conventional ones. In addition, this inorganic hard material has the advantages of having early strength, low shrinkage, and white. Furthermore, this inorganic hard material has the advantage of having fire resistance. Therefore, the inorganic hard material of this example can be used as an interior / exterior panel base material, a tile panel base material, or a paving stone base material, a sheet pile, or the like.

Examples of the present invention will be described below.

First embodiment

An inorganic hard material was prepared using slag for reducing steelmaking, desulfurized gypsum, glass fiber and a water-soluble sizing agent, and a performance evaluation test of the material was conducted.

First, 5% polyvinyl alcohol (PVA: degree of polymerization: 500) was added to an omni mixer so that 40 parts by weight was added to 100 parts by weight of the inorganic hard material substrate,
Then, desulfurization gypsum and reducing slag in the amounts shown in Table 1 were added in this order, and further 25 mm glass chopped strands were added at a ratio of 5 parts by weight with respect to 100 parts by weight of the inorganic hard material substrate, and 2 Mix for 20 minutes, 20x50x1c
It is poured into a plate frame of m, solidified and cured at room temperature for 10 days,
An inorganic hard material of this example was prepared (sample number: 1 to 1
3).

[0040]

[Table 1]

Next, a performance evaluation test of the obtained inorganic hard material was conducted by a bulk density measurement test and a bending strength measurement test.
The test was conducted using the inorganic hard material 10 days after the casting. The obtained results are shown in Table 1.

First, in the bulk density measurement test, a predetermined amount of the obtained inorganic hard material was cut out and the bulk density (g / cm ³ ) was measured according to JIS5201.

The bending strength measurement test was carried out using a 10 ton Amsler hydraulic tester under the conditions of a span interval of 140 mm and a load speed of 1 mm / min.

For comparison, a hard material for comparison was prepared in the same manner as in the first embodiment except that the composition of the inorganic hard material substrate was as shown in Table 1 (Sample Nos .: C1 to C3). ),
The bulk density measurement test and the bending strength measurement test were performed as described above. The results are also shown in Table 1.

As is clear from Tables 1 and 2, the inorganic hard material of the present invention according to the present embodiment is 85 kg in the air-dried state.
f / cm ² or more, bending strength is 45 kgf / cm even in a saturated state
It can be seen that extremely high strength of ² or more is obtained.
On the other hand, in the case of the comparative hard material, the flexural strength was low at 30 kgf / cm ² or less when the water was saturated.

Second embodiment

An inorganic hard material was prepared by using a steelmaking reduction slag, desulfurized gypsum, glass fiber, and a water-soluble sizing agent, and a water retention agent was further added as an additive to perform a performance evaluation test of the material.

First, 25 parts by weight of a substrate powder containing 75 parts by weight of reducing slag and 25 parts by weight of desulfurized gypsum were used.
The amount of mm chopped strand shown in Table 2, CMC 0.3 part by weight as a water retention agent, and 5% polyvinyl alcohol (PVA: degree of polymerization 500) as a water-soluble sizing agent were used [w
/C=0.4], an inorganic hard material of this example was prepared in the same manner as in the first example (Sample Nos. 4 to 6).

[0049]

[Table 2]

Next, a performance evaluation test of the obtained inorganic hard material was carried out by a bulk density measurement test and an air dry bending strength measurement test in the same manner as in the first embodiment. The obtained results are shown in Table 2.

For comparison, a hard material for comparison was prepared in the same manner as in the second embodiment except that glass fiber was not added (Sample No. C4). A bending strength measurement test was performed. The results are shown in Table 2.
Are also shown.

As is clear from Table 2, it is understood that the inorganic hard material of this example has an extremely high bending strength of 80 kgf / cm ² or more.

Third embodiment

Steelmaking reduction period slag, desulfurization gypsum, glass fiber and water-soluble sizing agent are used, and the concentration of the water-soluble sizing agent is changed to 4
A kind of inorganic hard material was produced and a performance evaluation test of the material was conducted.

First, 100 parts by weight of a substrate powder containing 75 parts by weight of reducing slag and 25 parts by weight of desulfurized gypsum was added to a polyvinyl alcohol (PVA: polymerization degree 50) as a water-soluble sizing agent.
40 parts by weight of a PVA aqueous solution obtained by dissolving 0) as kneading water to a concentration shown in Table 3 was charged into an omni mixer,
Mix for 2 minutes. Next, 3 parts by weight or 5 parts by weight of 25 mm chopped strands were mixed to prepare an inorganic hard material of this example in the same manner as in the first example (sample number: 7 to 10).

[0056]

[Table 3]

Next, a performance evaluation test of the obtained inorganic hard material was carried out by a bulk density measurement test and an air dry bending strength measurement test in the same manner as in the first embodiment. The obtained results are shown in Table 3, respectively.

For comparison, a hard material for comparison was prepared in the same manner as in the third embodiment except that the water-soluble sizing agent was not added (Sample Nos. C5 and C6), and the same bulk material was used as described above. A density measurement test and a bending strength measurement test were performed. The results are also shown in Table 3.

As is clear from Table 3, the inorganic hard material of this example has a very high flexural strength of 80 kgf / cm ² or more.

Fourth Embodiment

Three kinds of inorganic hard materials were produced by changing the length of the glass fibers using slag for reducing steelmaking, desulfurization gypsum, glass fibers and water-soluble sizing agent, and the performance evaluation test of the materials was conducted. .

First, 100 parts by weight of a substrate powder containing 75 parts by weight of reducing slag and 25 parts by weight of desulfurized gypsum was added to polyvinyl alcohol (PVA: polymerization degree 50) as a water-soluble sizing agent.
0) as the kneading water and dissolved in P to a concentration of 2.5%
40 parts by weight of the VA aqueous solution was put into an omni mixer and mixed for 1 minute. Then, 5 parts by weight of chopped strands having the lengths shown in Table 4 were mixed to prepare an inorganic hard material of this example in the same manner as in the first example (Sample Nos. 11 to 11).
13).

[0063]

[Table 4]

Next, a performance evaluation test of the obtained inorganic hard material was carried out by a bulk density measurement test and an air-dry bending strength measurement test in the same manner as in the first embodiment. The obtained results are shown in Table 4, respectively.

As is clear from Table 4, the inorganic hard material of this example has higher strength as the fiber length is longer.

Fifth embodiment

Four kinds of inorganic hard materials were prepared by changing the water-cement ratio using the steelmaking reduction slag, the desulfurized gypsum, the glass fiber and the water-soluble sizing agent, and the performance evaluation test of the materials was conducted.

First, 100 parts by weight of a substrate powder containing 75 parts by weight of reducing slag and 25 parts by weight of desulfurized gypsum was added to a polyvinyl alcohol (PVA: polymerization degree 50) as a water-soluble sizing agent.
0) was dissolved in kneading water so as to have a concentration of 5%, put into an omni mixer so that the water-cement ratio was as shown in Table 5, and mixed for 1 minute. Then, 5 parts by weight of 25 mm long chopped strands were mixed to prepare an inorganic hard material of this example in the same manner as in the first example (Sample Nos. 14 to 1).
7).

[0069]

[Table 5]

Next, a performance evaluation test of the obtained inorganic hard material was conducted by a bulk density measurement test and an air-dry bending strength measurement test in the same manner as in the first embodiment. The test was conducted using an inorganic hard material 4 weeks after the pouring. The obtained results are shown in Table 5, respectively.

As is clear from Table 5, it is understood that the inorganic hard materials of this example all exhibit high specific strength.
It should be noted that when the water-cement ratio is small, the specific strength is not so high, probably because the dispersion of the fibers is relatively insufficient, and it can be seen that the specific strength can be increased as the water-cement ratio is increased. Therefore, it is understood that the water-cement ratio of about 0.4 is preferable in order to maximize the fiber reinforcing effect.

Sixth Embodiment

An inorganic hard material was prepared using slag for reducing steelmaking, desulfurization gypsum, glass fiber and a water-soluble sizing agent, and a performance evaluation test of the material was conducted.

First, 100 parts by weight of a substrate powder containing 75 parts by weight of reducing slag and 25 parts by weight of desulfurized gypsum was used as a water-soluble sizing agent with polyvinyl alcohol (PVA: polymerization degree 50).
0) is dissolved in kneading water to a concentration of 2.5%, and the mixture is added to an omni mixer so that the water-cement ratio becomes 0.35.
Mix for 1 minute. Then, 5 parts by weight of 25 mm long chopped strands were mixed to prepare an inorganic hard material of this example in the same manner as in the first example (Sample No. 1).
8).

Next, a performance evaluation test of the obtained inorganic hard material was carried out by the air dry bending strength measurement test in the same manner as in Example 1 except that the period from the pouring was changed as shown in Table 6. . The obtained results are shown in Table 6, respectively.

[0076]

[Table 6]

As is clear from Table 6, the inorganic hard material of this example is excellent in early strength.

Seventh Embodiment

Using two kinds of inorganic hard material substrates, glass fibers and a water-soluble sizing agent were mixed to prepare an inorganic hard material, and a performance evaluation test of the material was conducted.

First, a substrate powder [substrate powder: A] containing 75 parts by weight of reducing slag and 25 parts by weight of desulfurization gypsum, and a substrate powder [substrate powder: B] in which 100 parts by weight of granulated blast furnace granulated sand was added to the substrate powder A. ] Two types of substrate powders were prepared.

Next, 100 parts by weight of the substrate powder was mixed with polyvinyl alcohol (PVA: polymerization degree 5) as a water-soluble sizing agent.
(00) is dissolved in kneading water so as to have a concentration of 5%, and the mixture is put into an omni mixer so that the water-cement ratio becomes 0.4.
Mix for minutes. Next, 5 parts by weight of 25 mm long chopped strands were mixed to prepare an inorganic hard material of this example in the same manner as in the first example (Sample Nos. 19 and 2).
0).

Next, a performance evaluation test of the obtained inorganic hard material was carried out by a bulk density measurement test and an air dry bending strength measurement test in the same manner as in the first embodiment. The test was conducted under the conditions shown in Table 7, that is, the elapsed time from the pouring and the atmosphere. The obtained results are shown in Table 7.

[0083]

[Table 7]

As is clear from Table 7, the inorganic hard material of this example is excellent in weather resistance and can be sufficiently used as a building material especially in the air-dried state.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location // (C04B 28/00 14:42 C 2102-4G 24:26) B 2102-4G (72) Inventor Miyashita Kanji Wano Wari, No. 1 Arano-machi, Tokai City, Aichi Prefecture, Aichi Steel Co., Ltd. (72) Inventor Haruyasu Ishizama No. 1, Wano Wari, Arao-machi, Tokai City, Aichi Steel Co., Ltd.

Claims (1)

[Claims] 1. A substrate powder comprising 12CaO.7Al ₂ O ₃ or / and its solid solution and γ-2CaO.SiO ₂ and 10 to 35 parts by weight of gypsum per 100 parts by weight of the substrate powder. Inorganic hard material base material as the main component, 1.0 to 10.0 parts by weight of glass fiber, and 0.1 to 5.0 parts by weight of water-soluble glue with respect to 100 parts by weight of the inorganic hard material base material. An inorganic hard material comprising an agent.