JPH10109370A - Water resistant honeycomb structural material and water resistant coating composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a honeycomb structural material having fire resistance and, at the same time, high water resistance. SOLUTION: A coating film 14 made of polyorganosilcesguioxane (ladder type silicone polymer) is formed on the surface of a honeycomb structural material main body 11 consisting of flame-retardant or incombustible base paper, especially incombustible sheet 12 mainly made of sepiolite. This inorganic polymer is excellent in water repellency and has high bending strength and especially high heat resistance due to its ladder type polymeric structure, resulting in obtaining a honeycomb structural member having excellent fire resistance and water resistance. Further, this film 14 can be formed out of an one-pack type cold curable coating composition consisting of a pre-reaction product (pre-polymer) of a mixture of organotrialkoxysilane, water and alumimum chelate as a reaction accelerator, a phosphate as a reaction retarder and an organic solvent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a honeycomb structural material used as a core material of a panel for building material such as a wall material, a shutter, a door, a floor, etc., or a core material of an interior panel of a railroad vehicle, and particularly to a fire-resistant material. Water-resistant honeycomb structural material suitable for applications requiring water resistance, and a water-resistant coating composition that can be suitably used for the production thereof, more specifically, a water-resistant coating for forming a cured film of polyorganosilsesquioxane It relates to a composition.

[0002]

2. Description of the Related Art Conventionally, panels for building materials, such as doors, partitions, and wall materials, have high rigidity, strength, impact resistance, etc., while being lightweight. The honeycomb structural material, which is a honeycomb-shaped aggregate of columnar cells, is used as the core material.

[0003] This honeycomb structural material is made of a sheet-like material, provided with adhesive strips at regular intervals, alternately shifted by a half pitch, and laminated and bonded, and then cut into a desired width. It is generally manufactured by a method such as spreading. And as the sheet-like material, it is much cheaper than metal materials such as aluminum alloy and stainless steel,
Pulp paper materials such as kraft paper are generally used because they are easy to handle. Further, a so-called paper-based honeycomb structural member formed from such a paper material has heat insulating and sound insulating properties, and also has effects such as preventing dew condensation.

However, a honeycomb structural material formed from a simple pulp paper material is easily burnt and thermally deteriorated because the pulp material is made of organic cellulose and is flammable. Therefore, such pulp paper materials are usually subjected to a flame retarding treatment with a flame retardant such as ammonium phosphate or a halogen compound. However, although its flammability can be reduced to some extent, it has its limitations. Therefore, a honeycomb structural material using such a pulp paper material as a base paper is not sufficient in terms of fire resistance or fire resistance. In the meantime, asbestos fiber paper has conventionally been a typical paper material having excellent nonflammability and fire resistance, but asbestos fiber has been found to be harmful to health and is not used at present.

Therefore, from the viewpoint of excellent fire resistance or fire resistance, various types of honeycomb structural members formed by using a flame-retardant or non-combustible paper material instead of asbestos fiber paper as a base paper have been developed. Also known. One of the typical examples is to use an inorganic aluminum hydroxide powder of 50 to
This is a honeycomb structural material using as a base paper a high aluminum hydroxide content paper made together with a pulp material at a high ratio of 90% by weight.
No. 945, JP-A-63-178033, JP-B-5-57104, JP-A-5-57825, etc., are disclosed in various modes. According to this honeycomb structural material, in particular, the aluminum hydroxide has a self-extinguishing property, releases moisture by heating and undergoes endothermic decomposition, so that excellent fire resistance can be obtained. Further, the fire resistance can be further improved by coating the surface of the formed honeycomb structure with a water glass composition and forming a silicate coating.

[0006] Further, similar honeycomb structural materials having excellent fire resistance include, for example, inorganic materials such as hydrated calcium borate (peridotite) or magnesium hydroxide as described in Japanese Patent Publication No. 3-4679. It can also be obtained by a flame-retardant papermaking sheet containing a large amount of powder.

[0007] However, even better fire resistance can be obtained by using a substantially non-combustible sheet made mainly of sepiolite developed by the present applicant.
That is, in this non-combustible sheet, is sepiolite itself, which is a fibrous hydrated magnesium silicate mineral, excellent in binding or solidifying properties, and is it unnecessary to use a pulp material for securing the shape retention of the paper-made sheet? , Or minimized, so that it is almost completely non-flammable, and sepiolite is sinterable, so that it retains its shape well when exposed to flame or high heat. Therefore, according to the honeycomb structural member formed by using the non-combustible sheet as the base paper, particularly excellent fire resistance can be obtained. In addition, about this honeycomb structural material, for example,
No. 229,042. It also discloses that an aqueous inorganic impregnating agent such as a water glass composition is further coated on the surface of a honeycomb structural material formed from a noncombustible sheet.

[0008]

As described above, by using a flame-retardant or non-combustible sheet made mainly of an inorganic material as a base paper and forming a honeycomb structural material, the need for disaster prevention is also met. A honeycomb structural material having suitable excellent fire resistance can be obtained. Further, particularly excellent fire resistance can be obtained by using a non-combustible sheet made of sepiolite as a main material as a base paper. These honeycomb structural materials are excellent in heat insulating properties and sound insulating properties, and have effects such as no dew condensation or corrosion.

However, since such a honeycomb structural material is formed by using a papermaking sheet as a base paper, it tends to be weak to water and poor in water resistance. That is, since the base paper made of a sheet of paper easily absorbs water, if water adheres to the surface, the water easily penetrates into the tissue of the base paper, and as a result, the tissue swells due to the moisture and the bond is released. And the strength of the honeycomb structural material is reduced. This is the same in the case of a honeycomb structural material formed of a non-combustible sheet mainly composed of sepiolite, which has a higher water resistance than others due to the solidification of sepiolite itself, but is exposed to water for a long time. When this occurs, its consolidation force is also lost, and similarly, the tissue swells and its strength decreases.

The water resistance is such that when the surface of the honeycomb structural material is coated with a water glass composition,
Improve to some extent. This is because not only the fire resistance and the like are improved by the formed inorganic silicate coating, but also the texture of the base paper is strengthened, thereby preventing the swelling of the tissue or a decrease in bonding force due to moisture. However, since the silicate coating made of water glass is a vitreous brittle coating, forming this coating with a sufficient thickness for water resistance adversely affects the flexibility of the honeycomb structural material, and furthermore, Impact properties and the like are also deteriorated. On the other hand, the improvement of the water resistance can also be achieved by increasing the amount of a binder as a paper-strength enhancer added at the time of papermaking, particularly a binder made of a thermosetting resin. However, there is a limit to the amount of the binder to be added, and if the amount is too large, the rigidity of the base paper is excessively increased and its handling property is deteriorated, and the excellent nonflammability of the base paper is impaired. Become. Even when the silicate film is formed relatively thick and the amount of the binder is relatively large, the permeation of water into the tissue of the base paper itself is not prevented. It is not always perfect in terms of long-term reliability.

[0011] Therefore, the honeycomb structural material formed from the flame-retardant or non-flammable base paper has excellent fire resistance suitable for use as a fire protection building material, but has poor water resistance.
In particular, it is still insufficient in terms of reliability for use on outer walls through which rainwater easily penetrates, and around water such as baths and kitchens.

Accordingly, an object of the present invention is to provide a water-resistant honeycomb structural material having excellent water resistance as well as fire resistance. In addition, a second object of the present invention is to provide a one-part, room temperature-curable, water-resistant coating composition capable of forming a film having excellent water resistance and heat resistance. is there.

[0013]

SUMMARY OF THE INVENTION The first object of the present invention is to provide a specific type of polymer structure on the surface of a honeycomb structural material body made of fire-resistant, ie, flame-retardant or non-flammable base paper. By forming a coating film of a polyorganosiloxane consisting essentially of

That is, the water-resistant honeycomb structural member according to the first aspect is composed of an aggregate of a large number of columnar cells, and is formed of a flame-retardant or non-combustible base paper.
And a coating film formed of polyorganosilsesquioxane formed on the surface of the base paper forming the honeycomb structural material body.

Here, the polyorganosilsesquioxane is represented by the following general chemical structural formula (I).
This is a polyorganosiloxane having a ladder-like polymer structure in which 1.5 oxygen atoms O are bonded per silicon atom Si.

[0016]

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In the formula, R represents a hydrocarbon group such as an alkyl group or an aryl group, and n is an integer of 1 or more.

This polyorganosilsesquioxane (ladder silicone polymer) not only has excellent water repellency, oxidation resistance, heat resistance, etc., which are generally common to polyorganosiloxanes, which are inorganic polymers, but also has a polymer structure. Since it has a ladder (ladder) shape, it has higher flexural strength and higher heat resistance than a normal polyorganosiloxane having a single-chain polymer structure. In other words, even if one of the binding chains is cleaved at one position by heat or the like, the polymer structure is not cut unless adjacent portions of the other binding chain are cleaved at the same time, and the cleavage site may be recombined. Because it is big. Therefore, in the above honeycomb structure material, a coating film made of polyorganosilsesquioxane, which is a ladder-type polymer having high flexural strength, is formed on the surface of the base paper forming the honeycomb structure material main body. Due to its water repellency, a honeycomb structural material having excellent water resistance can be obtained. In addition, since the honeycomb structural material itself is made of non-flammable or non-flammable base paper, and the coating film is non-flammable and has excellent heat resistance, a honeycomb structural material excellent in fire resistance can be obtained. Can be. That is, a honeycomb structural material having excellent water resistance as well as excellent fire resistance can be obtained.

As the base paper for forming the honeycomb structural material main body, a non-combustible sheet made of sepiolite as a main material is preferable. According to this non-combustible sheet, sepiolite has excellent binding or solidifying properties, so that organic components can be minimized, and since sepiolite has sintering properties, it is exposed to a flame or high heat. However, since the shape can be favorably maintained, a honeycomb structural material having more excellent fire resistance can be obtained.

That is, in the water-resistant honeycomb structural material according to the second aspect, the base paper forming the honeycomb structural material main body in the first aspect is formed of a non-combustible sheet made of sepiolite as a main material.

In the above-mentioned polyorganosilsesquioxane, the organo group R may be any hydrocarbon group, that is, an alkyl group or an aryl group. Particularly preferred are a methyl group or a phenyl group. In particular, in the case of a methyl group, the best water repellency is obtained, and in the case of a phenyl group, the best heat resistance is obtained.

That is, a water-resistant honeycomb structure material according to claim 3 is the water-resistant honeycomb structure material according to claim 1 or 2, wherein the organo group of the polyorganosilsesquioxane is at least one of a methyl group and a phenyl group. is there.

On the other hand, this polyorganosilsesquioxane coating film is formed by a one-part, room-temperature curable coating composition which is the second object of the present invention. Can be. The second problem is that a specific reaction inhibitor is added to a pre-reaction product obtained by hydrolytic polycondensation of a specific organosilane compound and water with the addition of a specific reaction accelerator.
It is solved by liquefaction.

That is, in the water-resistant honeycomb structural material according to claim 4, the coating film according to claim 1 or 2, wherein the coating film comprises an organotrialkoxysilane, water for hydrolyzing the same, and aluminum as a reaction accelerator. A mixture containing a chelate, a pre-reaction product containing a prepolymer of polyorganosilsesquioxane obtained by pre-reaction, and a phosphate ester as a reaction inhibitor,
The coating composition is formed by applying a coating composition containing an organic solvent to the surface of a base paper forming a honeycomb structural material main body and drying.

The water-resistant coating composition according to claim 5 is obtained by preliminarily preliminarily reacting a mixture containing an organotrialkoxysilane, water for hydrolyzing the same, and an aluminum chelate as a reaction accelerator. A pre-reaction product containing a prepolymer of polyorganosilsesquioxane, and a phosphate ester as a reaction inhibitor,
And an organic solvent.

Here, the organotrialkoxysilane is hydrolyzed and polycondensed by the reaction with water to produce the polyorganosilsesquioxane represented by the above general formula (I). This process can be generally illustrated by the following reaction formula (II).

[0027]

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In the formula, R represents a hydrocarbon group of an alkyl group or an aryl group, and R 'is a hydrocarbon residue forming the same or different alkoxyl group as R.

That is, in the organotrialkoxysilane, the alkoxyl group is hydrolyzed by water, the corresponding alcohol R'OH is separated, and the silanol group SiOH formed is combined with the silanol group or alkoxyl group of another organotrialkoxysilane. The polycondensation results in the formation of a polyorganosilsesquioxane, a ladder-like polymer.

The aluminum chelate functions as a reaction accelerator for catalytically promoting the hydrolysis / polycondensation reaction, and enables the coating composition to be cured at room temperature. Further, the phosphoric acid ester blocks a silanol group at the terminal of the polyorganosilsesquioxane prepolymer, or inhibits a reaction promoting action of aluminum chelate, thereby suppressing a curing of the coating composition. And makes the coating composition one-part. Therefore, when this coating composition is applied and dried, the phosphate ester volatilizes together with the organic solvent, and as a result, the water in the air causes the hydrolysis polycondensation reaction of the polyorganosilsesquioxane prepolymer. The process proceeds again, and finally a film made of the cured product is formed. Therefore, according to this coating composition, it can be formed as a one-part coating composition which is curable at room temperature and is one-part. Then, by applying the coating composition to the substrate surface, a cured coating film composed of polyorganosilsesquioxane can be formed with good adhesion, and the substrate has excellent water resistance and the like. Can be given.

Preferred embodiments of the coating composition are as follows.

That is, in the water-resistant coating composition according to claim 6, the organotrialkoxysilane is methyltriethoxysilane, and the water for hydrolyzing the organotrialkoxysilane is acidic water containing an acid catalyst. It is characterized by the following.

The water-resistant coating composition according to claim 7 is the composition according to claim 5, wherein the aluminum chelate is β-
It is characterized by comprising an aluminum alkoxide using a diketone or a β-ketonate as a chelating agent.

[0034] In the water-resistant coating composition according to the eighth aspect, the phosphate ester according to the fifth aspect, wherein the phosphate ester has 1 to 1 carbon atoms.
8 is a mono- or diester of an aliphatic alcohol and phosphoric acid, that is, an acidic phosphoric acid ester.

The water-resistant coating composition according to the ninth aspect of the present invention comprises methyltriethoxysilane, water for hydrolyzing the same, hydrochloric acid as an acid catalyst, aluminum diisoproxide ethyl acetoacetate or aluminum di-sec-butoxide. A pre-reaction product containing a prepolymer of polymethylsilsesquioxane obtained by preliminarily preliminarily reacting a mixture containing aluminum chelate as a reaction accelerator composed of ethyl acetoacetate, and an acidic phosphorus as a reaction inhibitor It contains an acid methyl ester and an organic solvent composed of an aliphatic alcohol having 2 to 5 carbon atoms.

[0036]

Embodiments of the present invention will be described below.

FIG. 1 is an enlarged perspective view showing the whole and a part of a honeycomb structural member according to an embodiment of the present invention.

As shown in FIG. 1, the honeycomb structural member of the present embodiment, which is indicated as a whole by 10, is based on a base paper 12 that is fire-resistant, ie, flame-retardant or non-combustible, and has an organic or inorganic adhesive 13 And a honeycomb structural material main body 11 formed by using the same. The honeycomb structural material body 11 is a structure in which a large number of columnar cells are formed in a honeycomb shape by partition walls in the thickness direction, that is, an aggregate of a large number of columnar cells. It is most commonly and preferably formed into a hexagonal cross section as described above, but it can also be formed into other polygons such as a quadrangle, or a non-rectangular shape including a circular or curved portion, and the like. It can be a combination.

The surface of the honeycomb structural material body 11, that is, the surface of the base paper 12 forming the same,
A coating film 14 substantially consisting of the polyorganosilsesquioxane represented by the above-mentioned general chemical structural formula (I), that is, a polyorganosiloxane having a ladder (ladder) polymer structure is formed. This ladder-like polyorganosiloxane has flame retardancy (non-flammability) as an inorganic polymer (semi-inorganic polymer), and also has heat resistance (thermal stability), which is a general property of polyorganosiloxane, In addition to having water repellency, oxidation resistance, and excellent dielectric properties,
Due to the ladder-like polymer structure, heat resistance is higher and bending strength is higher than that of a polyorganosiloxane having a single-chain (linear) polymer structure. That is, with respect to heat resistance, a general silicone resin having a single-chain (linear) polymer structure is 23%.
Decomposition starts at a temperature of about 0 ° C., and the shape cannot be maintained at 400 ° C. or higher, whereas the ladder-type polymer structure is stable even at 500 ° C. The bending strength is about twice that of a single-chain (linear) polymer structure.

Therefore, according to the coating film 14 made of polyorganosilsesquioxane, which is a ladder-type silicone resin, moisture adheres to the surface of the base paper 12 due to its water repellency and penetrates into the tissue. Therefore, excellent water resistance can be given to the honeycomb structural body 11. And since this polyorganosilsesquioxane is chemically and physically stable by its polymer structure, its excellent water resistance can be maintained for a long time. On the other hand, the flammable organic substances on the surface of the base paper 12 are covered with the coating film 14 having excellent heat resistance, so that the nonflammability is improved and the fire resistance of the honeycomb structural body 11 is further improved. . Furthermore, this coating 1 made of a chain polymer
4 has a flexibility and a high bending strength. Therefore, according to the coating 14, unlike the silicate coating of the water glass composition, without impairing the appropriate flexibility of the honeycomb structural body 11. , Its strength can be increased.

Here, the organo group R of the polyorganosilsesquioxane can be any hydrocarbon group. Specific examples include an alkyl group such as a methyl group, an ethyl group, a propyl group, and a decyl group; an aryl group such as a phenyl group, a tolyl group and a xylyl group; an alicyclic hydrocarbon group; and a vinyl group. be able to. However, among these, as the organo group R, a methyl group and a phenyl group are particularly typical, and a methyl group,
That is, polymethylsilsesquioxane provides the best water repellency, and phenyl groups, that is, polyphenylsilsesquioxane, provide the best heat resistance. Therefore, the organo group R of the polyorganosilsesquioxane is preferably a methyl group or a phenyl group, or a combination thereof (copolymer). However, the most preferred is a methyl group because the heat resistance is already sufficient.

The coating film 14 consisting essentially of such polyorganosilsesquioxane is:
For example, it can be formed by the following ordinary method. That is, a polymer composed of polyorganosilsesquioxane is prepared in advance by a method such as reacting organotrichlorosilane with water under an alkaline catalyst and subjecting it to hydrolysis and polycondensation, and dissolving this in an appropriate solvent to prepare a coating composition. Material, and the base paper 1 of the honeycomb structural material body 11
2 and then drying. However, in order to maintain excellent water resistance for a long period of time, it is desirable that the coating film 14 is adhered to the surface of the base paper 12 with good adhesion. Therefore, the coating 14 composed of the polyorganosilsesquioxane is
It is preferably formed as a cured film by a curable coating composition, and therefore, is preferably formed by a one-part coating composition containing the prepolymer and curable at room temperature as described below.

The honeycomb structure material body 11, the base paper 12 forming the same, and the water-resistant coating composition for forming the coating film 14 will be described in detail below.

[Base Paper] As the base paper 12 forming the honeycomb structural material main body 11, it is difficult to use the obtained honeycomb structural material 10 because it has excellent fire resistance and is suitably used as a fire protection building material. A flammable or nonflammable papermaking sheet (paper material) is preferred.

Specifically, as such a paper material, for example, powders of inorganic substances having preferably bound water, such as aluminum hydroxide, hydrous calcium borate (peridotite), and magnesium hydroxide, are used. A mixed paper containing a large amount can be mentioned. The inorganic powder can be generally contained in a proportion of 50 to 90% by weight based on the whole. The higher the content, the more excellent flame retardancy or non-flammability is obtained, but those inorganic powders generally have poor binding properties. The material must be at least 10% by weight or more. As already known, the surface thereof can be further coated with an inorganic powder in order to improve the fire resistance of the paper material. Further, the coating of the water glass composition can be performed as needed.

However, the most preferable base paper 12 is a non-combustible sheet made of sepiolite as a main material. Sepiolite, also called mountain skin, etc., is a viscous mineral made of hydrous magnesium silicate with fibrous properties,
The surface has a highly reactive hydroxyl group and has basic properties such as adsorptivity, thixotropic, solidifying properties, and sinterability. Therefore, due to the solidification or binding properties of the sepiolite itself, the pulp material, which is an organic substance, is unnecessary or can be reduced to a very small amount, thereby obtaining a substantially nonflammable paper sheet. Can be. In addition, since sepiolite has sintering properties, when exposed to a flame or high heat, it is thermally decomposed and collapsed in aluminum hydroxide-rich paper, whereas in the case of this non-combustible sheet, sepiolite is Due to the mutual sintering, the original shape of the sheet is retained. That is, the non-combustible sheet containing sepiolite as a main material has an excellent shape retention that does not collapse even by high heat.

The non-combustible sheet can also be formed by separately forming sepiolite. However, in general, in order to ensure sufficient paper strength against bending and the like and thereby ensure good handling properties, in addition to sepiolite as a main material, a reinforcing fiber and a binder are added and included. It is preferable to form the slurry by papermaking. However, in this case, the ratio of sepiolite is preferably at least 75% by weight or more of the whole in order to sufficiently exhibit its characteristics.

Here, the reinforcing fibers are used to reinforce the obtained non-combustible sheet, and preferably, inorganic fibers are used. Specifically, metal fibers such as glass fiber, rock wool fiber, and stainless steel fiber, and ceramic fibers such as carbon fiber and alumina fiber can be used.
However, among these, glass fiber is most preferable from the viewpoint of material cost, aggregation effect at the time of papermaking, and the like. These inorganic fibers can be generally blended in an amount of 3 to 20% by weight based on the entire non-combustible sheet. In addition, as the reinforcing fiber, not only inorganic fiber but also organic fiber such as wood pulp, or flame-retardant phosphate pulp, or preferably fibrillated synthetic fiber such as aramid fiber can be used. . However, the compounding amount is
In order to make the nonflammability complete, the content is preferably 10% by weight or less based on the whole nonflammable sheet, and 5% by weight.
It is more preferred that:

[0049] Binders are also used to increase the mutual binding of the material components, thereby enhancing paper strength. As the binder, natural polymer compounds such as guar gum and starch can be used, but preferably, a synthetic resin that is a synthetic product can be used. As the synthetic resin, any of a thermoplastic resin and a thermosetting resin can be appropriately used, and preferably, a cationic, anionic, or nonionic resin having a combined action as a flocculant is used. can do.
Specifically, examples of the thermoplastic resin include acrylic resins such as polyacrylamide, polyvinyl alcohol, polyethylene oxide, and polyester resins. Further, as the thermosetting resin, an epoxy resin such as an epichlorohydrinated polyamide resin, a melamine resin,
An amino resin such as a urea resin can be used, and according to these, the paper strength particularly when wet can be increased. And
Binders composed of these high molecular compounds can be used alone or in appropriate combination, but the proportion is generally 5% by weight or less based on the entire noncombustible sheet in order to obtain excellent noncombustibility. It is preferred that
Since sepiolite has excellent caking properties, such a small amount is sufficient.

The non-combustible sheet containing sepiolite as a main component may further contain an inorganic powder such as aluminum hydroxide in addition to the reinforcing fibers and the binder. However, even in such a case, the ratio of sepiolite is preferably 75% by weight or more based on the whole, and the total amount of organic matter is 1%.
It is preferably 0% by weight or less.

The nonflammable sheet can be formed, for example, with the following composition.

<< Composition example of noncombustible sheet >> Sepiolite: 85% (% by weight) Glass fiber: 10% Pulp: 3% Vinylon fiber: 1% Acrylic resin According to the non-combustible sheet of this example, the total amount of organic components such as pulp is 5% by weight, and this organic component is heated at a high temperature (8%).
(00-1000 ° C.), but the sheet after carbonization hardly deteriorates in strength and has excellent heat-resistant shape retention. The non-combustible sheet also has water resistance and does not redissolve even when immersed in water. However, the strength is slightly reduced. The non-combustible sheet having this composition can be obtained by forming a slurry in which those material components are dispersed, and forming the slurry.

[Formation of Honeycomb Structural Material Main Body] By using such a flame-retardant or non-flammable papermaking sheet, particularly a base paper 12 composed of a non-combustible sheet mainly composed of sepiolite,
The honeycomb structural member main body 1 can be formed by, for example, the following method using an ordinary well-known method. In addition,
The thickness of the base paper 12 depends on the required strength and the like.
Generally, it is preferably about 0.2 to 1.0 mm.

That is, first, an inorganic adhesive is applied to the surface of the sheet-shaped base paper in a streak shape at a predetermined interval at a predetermined interval by screen transfer or roller application. As the inorganic adhesive, any adhesive such as a water glass type, a phosphate type, a colloidal silica type, and a colloidal alumina type can be used, but a colloidal silica type adhesive is preferable from the viewpoint of low permeability. Further, an organic adhesive such as vinyl acetate can be used in place of the inorganic adhesive, but the fire resistance,
In terms of heat resistance, an inorganic adhesive is more preferable. In addition, since the width of the strip of the inorganic adhesive determines the length of the overlapping portion of the honeycomb structural material body, by changing the width and pitch of the strip of the adhesive, the columnar cells of the honeycomb structural material main body are changed. The shape and dimensions can be changed as desired.

Then, a large number of sheet-like base papers on which the strips of inorganic adhesive are formed are overlapped with each other so that the strips of the adhesive are mutually shifted by a half pitch between adjacent base papers. Adhere each other by pressing from the direction. Next, the block composed of a large number of base papers bonded to each other is cut into a predetermined width corresponding to a desired thickness of the honeycomb structural material in a direction perpendicular to the strip of the adhesive. Then, by expanding the cut material from both sides, the honeycomb structural body 11 as shown in FIG. 1 is formed. In the case of a honeycomb structural material such as a roll core or a feather core, the method is different from such a method.
It can be formed in a similar manner including shaping.

Before forming the coating film 14 of polyorganosilsesquioxane, the surface of the honeycomb structure material body 11 thus formed is coated with a water glass composition, if necessary. And a silicate film can be formed. Thereby, the fire resistance, strength, and the like of the honeycomb structure main body 11 can be further improved.

[Water-Resistant Coating Composition] A water-resistant coating film 1 is formed on the surface of the honeycomb structural material body 11.
Suitable one-part coating compositions which are curable at room temperature and which are suitable for forming 4 are based on the following compositions: That is, a preliminary reaction containing a prepolymer of polyorganosilsesquioxane obtained by preliminarily reacting a mixture containing an organotrialkoxysilane, water for hydrolyzing the same, and an aluminum chelate as a reaction accelerator. And a phosphoric acid ester as a reaction inhibitor,
And an organic solvent that dissolves them. Each of these components or substances will be described.

<Organotrialkoxysilane> The organotrialkoxysilane, which is a main raw material component, has an organo group R consisting of one hydrocarbon at the silicon atom, as shown as a starting material in the above-mentioned reaction formula (II). A compound in which three alkoxyl groups R'O are bonded.

Here, the organo group R forms an organo group of the finally formed polyorganosilsesquioxane, and therefore, as described above, is a hydrocarbon group such as an alkyl group or an aryl group. And preferably a methyl or phenyl group, and most preferably a methyl group.

On the other hand, the alkoxyl group R'O is separated into the alcohol R'OH by hydrolysis. Therefore, the alkoxyl group R′O is easily hydrolyzed and can be a good solvent, as a methoxyl group, an ethoxyl group, a propoxyl group, a butoxyl group,
A lower alkoxyl group having 1 to 5 carbon atoms, such as a pentoxyl group, is preferred. In particular, a methoxyl group and an ethoxyl group are preferable in terms of excellent hydrolyzability and good water solubility. However, in the case of a methoxyl group, the hydrolysis rate tends to be too fast. Therefore, an ethoxyl group, from which ethanol is by-produced by hydrolysis, is most preferable, since preparation of the coating composition and one-part liquidification are easier.

Specifically, preferred organotrialkoxysilanes include methyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane,
Phenyltriethoxysilane can be mentioned, and these can be used in appropriate combination. Most preferred is methyltriethoxysilane.

<Water> Water is an important reactant for reacting with an organotrialkoxysilane to hydrolyze it and producing polyorganosilsesquioxane.

The water as a reactant reacts theoretically at a ratio of 1.5 mol with respect to 1 mol of the organotrialkoxysilane. However, from the viewpoint that the reaction is carried out in an organic solvent, the amount of water must be more than the theoretical amount of 1.5 mol in order to favorably perform the hydrolysis polycondensation reaction. Is preferred.
However, an excessive amount of water may impair the formation of the ladder type polymer. Therefore, the mixing amount of water is preferably about 1.2 to 2.0 times the theoretical amount, that is, about 1.8 to 3.0 mol per 1 mol of organotrialkoxysilane.

Incidentally, an acid catalyst can be added to the water to promote its hydrolysis action. This is particularly preferable when the above-mentioned organotriethoxysilane is used. The acid catalyst can be a common inorganic or organic acid such as hydrochloric acid.

<Aluminum chelate> Promotes the hydrolytic polycondensation reaction between organotrialkoxysilane and water,
As a reaction accelerator for producing a polyorganosilsesquioxane having a ladder-type polymer structure, an aluminum chelate compound is used. Organic tin compounds such as dibutyltin dilaurate are well known as this type of reaction accelerator (catalyst). However, in this coating composition, aluminum chelate is preferred because of its excellent reaction acceleration. Is used.

As the aluminum chelate, any chelate compound can be used. The most representative one is aluminum trialkoxide, which is a chelating agent, and β-diketones such as acetylacetone or β-diketones such as acetoacetate are used. Those chelated with ketone esters are particularly preferred. More specifically, for example, an aluminum alloy represented by the following structural formula:
Dissecondary (sec-) butoxide ethyl acetoacetate (chelate) or aluminum diisoproxide ethyl acetoacetate (chelate) can be given.

[0067]

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The amount of the aluminum chelate to be added may be a usual catalyst amount, and is generally about 0.005 to 0.01 mol per 1 mol of the organotrialkoxysilane.

<Phosphate ester> In order to suppress the hydrolysis polycondensation reaction of the pre-reaction product and make the coating composition one-packed, that is, to secure sufficient storage stability, the phosphate ester Is used. However, this phosphate ester does not completely stop the hydrolysis polycondensation reaction.

The phosphoric ester can be any ester compound of various phosphoric acids, but a lower alkyl ester having a relatively low molecular weight and soluble in water is preferred. Specifically, for example, the number of carbon atoms is 1 to 1 such as acidic phosphoric acid methyl ester, acidic phosphoric acid ethyl ester, acidic isopropyl phosphate, dibutyl phosphate, acidic butyl phosphate, and acidic 2-ethylhexyl phosphate. Preferred are mono- or diesters (acidic esters) of the aliphatic alcohol of No. 8 with phosphoric acid. The most preferred of these is acidic phosphoric acid methyl ester.

The amount of the phosphoric acid ester added is a catalytic amount, and it is preferable that the amount is approximately equimolar to the amount of the aluminum chelate.

<Organic Solvent> The organic solvent is used as a solvent for the hydrolysis and polycondensation reaction of the organotrialkoxysilane, and is used for appropriately diluting the produced preliminary reaction product.

Examples of such organic solvents include alcohols such as methanol, ethanol, propanol, isopropanol, butanol and pentanol, ketones such as acetone, ethers such as ethylene glycol, and esters such as ethyl acetate. Alternatively, aromatic solvents such as benzene and the like can be used alone or in combination of two or more. However, alcohols are preferred as organic solvents because alcohols are produced as by-products by hydrolysis of organotrialkoxysilanes.Also, since they are nontoxic and have good solubility in water, lower alcohols other than methanol are preferred. Alcohols, ie, aliphatic alcohols having 2 to 5 carbon atoms, are more preferred, and among them, ethanol and isopropanol are even more preferred.

<< Production Example of Coating Composition >>
This one-part coating composition that can be cured at room temperature,
For example, it can be manufactured and prepared from the following composition of these components or substances.

[0075] The aluminum chelate is aluminum diisoproxide ethyl acetoacetate (Al C ₁₂ H
₂₃ O ₅ ).

That is, this coating composition is produced or prepared by adding a reaction inhibitor solution B to a prereaction product obtained by preliminarily preliminarily reacting the prereaction mixture A and subjecting it to a hydrolytic polycondensation reaction. Therefore, although the composition of the coating composition, particularly the composition of the pre-reaction product, cannot be strictly specified, the pre-reaction product is at least polyorganosilsesquioxane, in this case, polymethylsilsesquioxane. It contains an oxane prepolymer.

When the pre-reaction mixture is pre-reacted, the aluminum chelate is preferably dissolved in an organic solvent (ethanol) and then mixed with an organotrialkoxysilane (methyltriethoxysilane). The aluminum chelate can be more uniformly dispersed. In addition, water as a reactant, in this case, 1N hydrochloric acid containing 0.4% hydrochloric acid, is added little by little to a solvent solution of an organotrialkoxysilane and an aluminum chelate mixed in advance. Is preferred. If you mix rapidly,
This is because gelling or a ladder-type polymer structure may not be obtained favorably. Also, during this mixing,
The reaction solution can be heated to, for example, about 40 ° C. to promote the hydrolysis polycondensation reaction. However, such a heating is not necessarily required because the reaction is a reaction involving exotherm. Rather, if the temperature of the reaction mixture rises excessively during the reaction, it is necessary to cool it.

The phosphoric acid ester (acidic phosphoric acid methyl ester) or a solution thereof as a reaction inhibitor can be added at any appropriate point before the gelation of the preliminary reaction product occurs. . However, the timing of adding such a reaction inhibitor is preferably a point in time when the hydrolysis polycondensation reaction of the pre-reaction mixture becomes slow and the temperature of the reaction solution starts to decrease. That is, the temperature of the pre-reaction mixture is increased by the heat generated during the reaction, and the peak temperature (eg, 7
0 ° C.), but thereafter, the concentration of the organotrialkoxysilane, which is the reactant, and water decreases, so that the reaction becomes slow and the liquid temperature decreases. Preferably, the addition of the phosphate ester is at such a point, whereby a well-grown polyorganosilsesquioxane prepolymer can be obtained and its gelling can be avoided with a margin. .

Then, by adding a phosphate ester,
Since the activity of the aluminum chelate is inhibited or the reactive terminal (silanol group) of the polyorganosilsesquioxane molecule is blocked, the progress of the hydrolytic polycondensation of the pre-reaction mixture is suppressed, whereby A stable one-part coating composition can be obtained. For example, in the case of the above example, the composition gels in several weeks when the temperature is close to 40 ° C., but is stable for at least about 3 months within a normal storage temperature of 15 ° C. When the temperature is lower than 5 ° C., almost complete stability can be obtained.

On the other hand, according to the coating composition thus produced or prepared, for example,
Honeycomb structural material body 11 by spraying or dipping
After coating and impregnating on the surface of the base paper 12, the coating film 14 of the cured polyorganosilsesquioxane can be easily formed only by leaving it to stand at room temperature and drying. That is, this coating composition is applied to base paper 12
When applied on the surface, the organic solvent evaporates,
Since the phosphoric acid ester, which is a reaction inhibitor, also volatilizes, the reaction promoting action of the aluminum chelate, which has been inhibited by that time, is activated again. Therefore, the hydrolysis polycondensation reaction proceeds again due to the moisture in the air, or the moisture contained in the coating composition concentrated by volatilization of the organic solvent, and the polyorganosilsesquioxane prepolymers are mutually reacted. By bonding, a coating film 14 made of the cured product is formed.
At the time of this curing, the silanol group or alkoxyl group remaining in the prepolymer reacts with and binds to the hydroxyl group of a material such as sepiolite forming the base paper 12. In other words, the coating composition can be cured even at room temperature, and as a result, a cured film 14 having good adhesion and durability can be formed. However,
The drying and curing by heating is not hindered at all, and in the case where the formation of a cured film in a short time is required, the drying and curing treatment of the coating composition is performed by heating in a humid atmosphere. Can be.

By the way, this coating composition is capable of forming a semi-inorganic film (cured film of polyorganosilsesquioxane) having water repellency and excellent heat resistance and bending resistance. It is particularly suitable for imparting more excellent water resistance to the fire-resistant honeycomb structural material. However, this coating composition is suitable for on-site use, in particular, because it can be cured at room temperature. Therefore, this coating composition,
It can be used not only as a honeycomb structural material but also as a general-purpose water-resistant or heat-resistant coating composition, for example, for surface treatment of an outer wall of a building.

Further, various kinds of fillers, pigments and the like can be blended into the coating composition, whereby the coating composition can be formed as a thick film coating composition or a colored coating composition. Furthermore, this coating composition has excellent compatibility with almost all organic synthetic resins such as polyvinyl acetal, polyvinyl formal, polyvinyl butyral and the like.
Therefore, by blending these organic synthetic resins with this coating composition, heat resistance is reduced,
The excellent properties of these organic synthetic resins, for example, the adhesiveness can be further improved.

[0083]

As described above, the water-resistant honeycomb structural member according to claim 1 comprises an aggregate of a large number of columnar cells,
A honeycomb structural material main body formed from flame-retardant or non-combustible base paper, and formed on the surface of the honeycomb structural material main body;
A coating film made of polyorganosilsesquioxane.

Therefore, according to this water-resistant honeycomb structural material, the honeycomb structural material main body is formed from a fire-resistant, flame-retardant or non-combustible base paper, and the surface of the base paper has water repellency. In addition, since a coating film made of polyorganosilsesquioxane having particularly excellent heat resistance and bending strength is formed by a ladder-like polymer structure, not only excellent fire resistance is obtained, but also that Due to the water repellency of the durable coating film, stable water resistance can be obtained for a long time. That is, according to this water-resistant honeycomb structural material, there is an effect that excellent water resistance as well as fire resistance can be obtained.

A water-resistant honeycomb structure according to a second aspect is the water-resistant honeycomb structure according to the first aspect, wherein the base paper forming the honeycomb structure main body is made of a non-combustible sheet made of sepiolite as a main material.

Therefore, according to this water-resistant honeycomb structural material, the base paper forming the honeycomb structural material main body is made of a non-combustible material made of sepiolite having excellent non-combustibility and shape retention during high heat. Since it is made of a sheet, in addition to the effect of claim 1, there is an effect that more excellent fire resistance can be obtained.

A third aspect of the present invention provides the water-resistant honeycomb structural material according to the first or second aspect, wherein the organo group of the polyorganosilsesquioxane is at least one of a methyl group and a phenyl group. is there.

Therefore, according to this water-resistant honeycomb structural material, the organo groups of the polyorganosilsesquioxane are the same as those of the methyl group which provides the highest water repellency and the phenyl group which provides the highest heat resistance. Since it is composed of one or more, in addition to the effect of claim 1 or claim 2, there is an effect that more excellent water resistance or fire resistance can be obtained.

The water-resistant honeycomb structural material according to claim 4 is characterized in that, in claim 1 or claim 2, the coating film comprises an organotrialkoxysilane, water for hydrolyzing the same, and an aluminum chelate as a reaction accelerator. A coating composition containing a pre-reaction product containing a polyorganosilsesquioxane prepolymer obtained by pre-reacting a mixture containing, a phosphoric acid ester as a reaction inhibitor, and an organic solvent, a honeycomb It is formed by applying it to the surface of a base paper forming the structural material body and drying it.

Therefore, according to this water-resistant honeycomb structural material, the coating film made of the polyorganosilsesquioxane is a cured film formed from the coating composition containing the prepolymer, so that the adhesion to the base paper is improved. In addition, since a coating film having higher durability can be obtained, there is an effect that more excellent water resistance can be obtained in addition to the effects of claim 1 or claim 2.

The water-resistant coating composition according to claim 5 is obtained by preliminarily reacting a mixture containing an organotrialkoxysilane, water for hydrolyzing the same, and an aluminum chelate as a reaction accelerator. It contains a pre-reaction product containing a polyorganosilsesquioxane prepolymer, a phosphoric ester as a reaction inhibitor, and an organic solvent.

Therefore, according to this water-resistant coating composition, a polyorganosilsesquioxane prepolymer obtained by hydrolytic polycondensation of a specific organosilane compound and water with the addition of a specific reaction accelerator is used. Since a specific reaction inhibitor is added to a pre-reaction product containing a polymer, it is a one-part composition capable of forming a cured film of polyorganosilsesquioxane having excellent water resistance, and There is an effect that a coating composition having room temperature curability can be obtained.

[0093] The water-resistant coating composition according to claim 6 is characterized in that the organotrialkoxysilane comprises methyltriethoxysilane and the water for hydrolyzing it comprises acidic water containing an acid catalyst. It is.

Therefore, according to this water-resistant coating composition, the organotrialkoxysilane is composed of methyltriethoxysilane, and the water for hydrolyzing it is composed of acidic water containing an acid catalyst. In addition to the effects, the hydrolytic polycondensation reaction of the organotrialkoxysilane can be performed at an appropriate reaction rate, whereby the coating composition can be easily manufactured or prepared.

The water-resistant coating composition according to claim 7, wherein the aluminum chelate is β-
It is characterized by comprising an aluminum alkoxide using a diketone or a β-ketonate as a chelating agent.

Therefore, according to this water-resistant coating composition, the aluminum chelate is composed of a specific chelate compound having an excellent reaction promoting property. There is an effect that the reaction can be favorably performed, and the curing reaction after application of the coating composition can also be favorably performed.

The water-resistant coating composition according to claim 8 is characterized in that, in claim 5, the phosphate ester comprises a mono- or diester of an aliphatic alcohol having 1 to 8 carbon atoms and phosphoric acid. is there.

Therefore, according to this water-resistant coating composition, since the phosphate ester is made of a specific compound having excellent reaction inhibiting properties, in addition to the effect of claim 5, the coating composition can be more easily made into a one-part composition. There is an effect that can be converted.

The water-resistant coating composition according to claim 9 comprises methyltriethoxysilane, water for hydrolyzing the same, hydrochloric acid as an acid catalyst, and aluminum.
A mixture containing diisoproxide ethyl acetoacetate or aluminum chelate as a reaction accelerator consisting of aluminum di-sec-butoxide ethyl acetoacetate contains a prepolymer of polymethylsilsesquioxane obtained by preliminarily pre-reacting the mixture. It contains a preliminary reaction product, an acidic phosphoric acid methyl ester as a reaction inhibitor, and an organic solvent comprising an aliphatic alcohol having 2 to 5 carbon atoms.

Therefore, according to the water-resistant coating composition, the organotrialkoxysilane and the like are each composed of a specific compound.
The production or preparation of the coating composition is easy, the hydrolysis / polycondensation reaction can be performed more favorably, and the coating composition can be more easily made into a one-part composition.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a honeycomb structural member according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Honeycomb structural material 11 Honeycomb structural material main body 12 Base paper 13 Adhesive 14 Coating coating

──────────────────────────────────────────────────続 き Continued on front page (51) Int.Cl. ⁶ Identification code FI E04C 2/36 E04C 2/36 A

Claims (9)

[Claims] 1. A honeycomb structural material body formed of an aggregate of a large number of columnar cells and formed of a flame-retardant or non-flammable base paper; and a polyorgano body formed on a surface of the base paper forming the honeycomb structural material body. A water-resistant honeycomb structural material, comprising: a coating film made of silsesquioxane. 2. The water-resistant honeycomb structural material according to claim 1, wherein the base paper forming the honeycomb structural material main body is made of a non-combustible sheet made of sepiolite as a main material. 3. The water-resistant honeycomb structure according to claim 1, wherein the polyorganosilsesquioxane has an organo group comprising at least one of a methyl group and a phenyl group. Wood. 4. The coating film comprises a mixture containing an organotrialkoxysilane, water for hydrolyzing the same, and an aluminum chelate as a reaction accelerator.
A pre-reaction product containing a polyorganosilsesquioxane prepolymer obtained by pre-reaction, a phosphoric acid ester as a reaction inhibitor, and an organic solvent are applied to the surface of the base paper. The water-resistant honeycomb structural member according to claim 1 or 2, which is formed by drying and drying. 5. A polyorganosilsesquioxane prepolymer obtained by preliminarily reacting a mixture containing an organotrialkoxysilane, water for hydrolyzing the same, and an aluminum chelate as a reaction accelerator. A water-resistant coating composition comprising a pre-reaction product, a phosphate as a reaction inhibitor, and an organic solvent. 6. The water-resistant coating composition according to claim 5, wherein the organotrialkoxysilane comprises methyltriethoxysilane, and the water for hydrolyzing the same comprises acidic water containing an acid catalyst. Stuff. 7. The water-resistant coating composition according to claim 5, wherein the aluminum chelate comprises an aluminum alkoxide having β-diketone or β-ketone ester as a chelating agent. 8. The phosphoric ester has 1 to 8 carbon atoms.
The water-resistant coating composition according to claim 5, comprising a mono- or diester of an aliphatic alcohol and phosphoric acid. 9. A reaction accelerator comprising methyltriethoxysilane, water for hydrolyzing the same, hydrochloric acid as an acid catalyst, and aluminum diisoproxide ethyl acetoacetate or aluminum di-sec-butoxide ethyl acetoacetate. A pre-reaction product containing a prepolymer of polymethylsilsesquioxane obtained by preliminarily pre-reacting a mixture containing an aluminum chelate as the above, an acidic phosphoric acid methyl ester as a reaction inhibitor; 5. An organic solvent comprising an aliphatic alcohol according to item (5).