JP2001039755A - Cement mortar composition for unevenness adjustment and method for executing application work of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a cement mortar composition for unevenness adjustment, which is capable of attaining fireproof performance and sufficiently adjusting unevenness through thick application of the composition to cement boards, after joint filling treatment of the boards by using as components of the cement mortar composition, cement, an inorganic expanded aggregate having a specific particle size distribution, fiber and a polymer in specified compositional ratios, respectively. SOLUTION: This cement mortar composition is produced by blending 100 pts.wt. of cement, 10-60 pts.wt. of an inorganic expanded aggregate, 0.1-20 pts.wt. of fiber and 1-10 pts.wt. of a polymer together to obtain a blend, and if necessary, further adding heavy-weight aggregate, a dispersing agent, a thickener, a regulated setting agent, a shrinkage reducing agent, and the like, to the blend. The composition is used in an execution method that comprises sticking cement boards to a wooden or steel structure; after joint filling treatment of the boards, subjecting the treated boards to unevenness adjustment by applying cement mortar to the boards, and then performing finishing work of the boards with a finishing material. As the inorganic expanded aggregate, such aggregate which has <=5 mm particle size and contains 0.1-2 wt.% of a fraction remaining on a sieve having 2.36 mm opening size, 15-25 wt.% of a fraction remaining on a sieve having 1.18 mm opening size and <=50 wt.% of a fraction remaining on a sieve having 0.60 mm opening size, is preferred. The cement mortar composition is mixed with 25-55 pts.wt. of water on the basis of 100 pts.wt. of the composition and the resulting cement mortar can be applied to the boards so as to form a cement mortar coating layer having a >=4 mm thickness and hardened, by a single run of execution of the application work.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cement mortar composition for adjusting irregularities which is suitable for constructing a wall of a building having a cement board attached to a wooden structure or a steel frame structure or the like, and the construction of the composition. About the method.

[0002]

2. Description of the Related Art The inventors of the present invention disclosed in Japanese Patent Application No. Hei 11-100612 a wooden siding or non-combustible siding material as a material for building walls including exteriors for general houses. In applying the base adjustment material to the siding material, the purpose was to solve problems such as embedding of fiber nets used for joint reinforcement, cracking, adjustment of unevenness of joints, etc. A
In addition to having the performance and workability of cement mortar for siding materials such as LC, the cement mortar composition for adjusting the groundwork that does not cause dryout at higher temperatures than conventional cement mortar, and the application of the composition A method was proposed.

[0003] However, the cement mortar composition for adjusting the foundation described in Japanese Patent Application No. 11-100612 can adjust the unevenness of joints, but can be used when the cement board is warped or at the seam of the cement board. When there is a step, there is a problem that it is difficult to adjust unevenness. In addition, in the case of construction, since the construction is often performed with the feeling of a plasterer, the application thickness at the time of construction may be less than the specified thickness, and it is difficult to control the application thickness at the time of construction. was there. Further, in order to impart fire-protection performance to a structure, it is necessary to apply the coating several times, resulting in a problem that the process becomes complicated.

It is also known that a mortar obtained by mixing a cement, an aggregate and a polymer is applied to a siding material and cured as a material for building walls of a building including an exterior for a general house (Japanese Patent Publication No. 58-385882). issue). In addition, cement mortars generally used for construction include a mortar composition obtained by mixing fine aggregates, fine aggregates, fibers, polymers and the like with cement, and a base adjustment material or cement which is kneaded with water or the like. It is also known to apply and harden a lightweight cement mortar that kneads a mortar composition containing inorganic admixtures such as perlite and silica sand and organic admixtures such as organic aggregates and organic fibers with water. (1995 Architectural Finishing Material Guidebook, edited by the Japan Architectural Finishing Material Manufacturers Association, published on April 20, 1995).

However, in the former method, the mortar must be applied twice, that is, undercoating and overcoating in order to apply the mortar thickly. In addition, in the latter base adjustment material, even if it is applied to a cement board, it is easy to crack and unevenness of joints, and it is difficult to adjust unevenness due to warpage of the board, and furthermore, to impart fire protection performance To. In addition, the lightweight cement mortar has a problem that the efficiency is poor because it must be applied thickly and must be applied several times.

[0006]

SUMMARY OF THE INVENTION The present invention relates to a material for building walls, including exteriors for general houses, which is constructed by attaching a cement board to a wooden or steel structure or the like. When applying cement mortar to cement boards that have been subjected to the joint treatment described in No. 4, a single application can apply a thickness of 4 mm or more, making it possible to adjust the unevenness of the steps that occur at the joints of the cement boards, etc. Provide a cement mortar composition for uneven land adjustment that can control the coating thickness at the time of construction to 4 mm or more without providing a special process, and can provide fire protection performance to the structure with one coating operation Is to do.

[0007]

Means for Solving the Problems As a result of intensive studies, the present inventors have added a specific amount of inorganic foamed aggregate, fiber and polymer having a specified particle size to cement and kneaded the resulting mixture. By applying and curing the cement mortar composition for land adjustment, it can be applied with a thickness of 4 mm or more in one application,
It is possible to adjust the unevenness of the steps that occur at the joints of cement boards, etc., and it is possible to control the coating thickness at the time of construction to 4 mm or more without providing a special process, and to apply the structure to one application work The present inventors have found that a cured product capable of imparting fire-prevention performance is formed, and completed the present invention.

[0008] That is, the first invention of the present invention relates to a construction method in which a cement board is attached to a wooden structure or a steel frame structure, joint processing is performed, unevenness is adjusted with a cement mortar, and finishing is performed with a finishing material. A cement mortar for adjusting irregularities to be used, which comprises 100 parts by weight of cement and inorganic foam aggregate 1
A cement mortar composition for adjusting a foundation, which is adjusted to a range of 0 to 60 parts by weight, 0.1 to 20 parts by weight of a fiber and 1 to 10 parts by weight of a polymer. ”.

The second invention of the present invention relates to "25 to 55 parts by weight based on 100 parts by weight of the cement mortar composition for adjusting unevenness.
A method for applying a cement mortar composition for adjusting unevenness, characterized in that a kneaded material obtained by kneading with parts by weight of water is applied to a cement board which has been subjected to joint treatment and is hardened by coating at least 4 mm. ”.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The cement board referred to in the present invention is a wood chip cement board, a calcium silicate board (commonly referred to as a calcical board) or a cement having hydraulic properties, to which aggregates and various additives are added as required. Kneaded with water, cured, embedded and reinforced with a fiber mesh as required, and formed into a plate shape, for example, "Delacrete cement board" manufactured by Mitsubishi Rayon Co., Ltd.

[0011] The cement mortar composition for controlling irregularities, which is the object of the present invention, is a cement having hydraulic properties, in which a material mixing ratio is defined within a predetermined range, and a specific particle size and a specific amount of inorganic foam. It is composed of aggregate, specific amount of polymer, further specific amount of fiber, and various additives such as curing regulator, dimensional stabilizer, thickener, etc., which are used as needed, to which specific amount of water is added, and Kneaded with a mixer.

As the hydraulic cement used in the present invention, various cements such as ordinary Portland cement, early-strength Portland cement, moderately heated Portland cement, blast furnace cement, silica cement, fly ash cement, alumina cement and jet cement are used. be able to.

The inorganic foam aggregate used in the present invention is obtained by adjusting the particle size of an ore such as obsidian, perlite, igneous rock, vermiculite, etc., and then rapidly baking it at about 1000 ° C. to form a foam. One type or a combination of two or more types can be used. The particle size of the inorganic foamed aggregate is 5 mm or less, and the ratio of those remaining on a sieve with an opening of 2.36 mm is 0.1 to 2% by weight, and the ratio of those remaining on a sieve with an opening of 1.18 mm is It is preferable that the proportion of the substance remaining on the sieve having a mesh size of 15 to 25% by weight and 0.60 mm is 50% by weight or less. When the particle size exceeds 5 mm and the ratio of the one remaining on the sieve with a mesh size of 2.36 mm exceeds 2% by weight, the inorganic foamed aggregate appears as irregularities on the surface of the cured product, and the surface property of the cured product is increased. Decrease. Openings2.
If the ratio of the residue on the 36 mm sieve is less than 0.1% by weight, the thickness of a single coating cannot be 4 mm or more, and it is difficult to control the coating thickness at the time of construction, and the fire prevention performance is obtained. I can't. If the ratio of the residue on the sieve having an opening of 0.60 mm exceeds 50% by weight, the workability is reduced. The amount of the inorganic foamed aggregate varies slightly depending on the type and combination of the inorganic foamed aggregate, but is 10 to 100 parts by weight of the cement.
Preferably, it is 60 parts by weight. If the compounding amount is less than 10 parts by weight, the amount of cement increases and cracks easily occur, and at the same time, fire prevention performance cannot be obtained. On the other hand, if it exceeds 60 parts by weight, the workability is remarkably reduced because the amount of aggregate is too large.

The fibers used in the present invention are necessary to prevent cracks or cracks, and include inorganic fibers such as alkali-resistant glass fibers, carbon fibers, and steel fibers, vinylon fibers, nylon fibers, and polypropylene fibers. Organic fibers can be used alone or in combination of two or more.

The amount of the fiber varies slightly depending on the type and combination of the fibers, but is 0.1 to 20 parts by weight, preferably 1 to 10 parts by weight, more preferably 3 to 5 parts by weight based on 100 parts by weight of cement. Department is good. 0.1
If the amount is less than part by weight, the effect of adding the fiber is not obtained, and cracks and cracks are easily generated. If the amount exceeds 20 parts by weight, the fibers are exposed on the surface, and the surface properties are deteriorated, and the workability is also deteriorated. Although the fiber length is not particularly limited, it is preferable to use a fiber having a length in the range of 3 to 18 mm from the viewpoint of cracks and surface properties.

The polymer used in the present invention is ethylene-vinyl acetate copolymer, acrylic acid or acryl-styrene copolymer, vinyl acetate, styrene-butadiene copolymer, vinyl acetate-vinyl versatate copolymer. Products, vinyl acetate-vinyl versatate-acrylic copolymer, vinyl acetate-vinyl versatate-vinyl laurate copolymer, and the form thereof may be an emulsion or a re-emulsifying powder. As the type of the polymer, an ethylene-vinyl acetate copolymer is preferably used. The compounding amount of the polymer is 1 to 10 parts by weight, preferably 3 to 7 parts by weight in terms of the polymer solid content based on the cement weight part.
Good by weight. If the compounding amount is less than 1 part by weight, water is quickly sucked into the cement board and workability is poor. Also, 1
If the amount is more than 0 parts by weight, the amount of the polymer becomes excessive, for example, it is difficult to suppress the iron, and the workability is deteriorated, for example, the viscosity is increased and the solid is adhered.

The cement mortar composition for controlling unevenness of the present invention further comprises heavy aggregates such as silica sand, mountain sand, river sand, and sea sand.
A dispersant, a thickener, a setting regulator, and a shrinkage reducing agent may be added as needed.

As the weight aggregate such as silica sand that can be used in the present invention, those having a controlled particle size, those having a particle size distribution, and those that have been pulverized can be used. Is preferably equal to or finer than the inorganic foamed aggregate.
The amount of heavy aggregate such as silica sand is 0
A good range is from 50 to 50 parts by weight. If the amount exceeds 50 parts by weight, the adhesiveness to the substrate tends to be poor.

The dispersants usable in the present invention include:
Melamine formalin condensate sulfonate, lignin sulfonate, β-naphthalene sulfonic acid aldehyde condensate, polyalkylallyl sulfonate, polycarboxylate, alkyl naphthalene sulfonate, alkyl naphthalene sulfonate formalin condensate, etc. And these can be used alone or in combination of two or more. The types of salts of the above compounds are sodium, potassium, calcium and the like.

The thickener which can be used in the present invention has a function of improving the workability and adhesiveness of the composition of the present invention, and includes methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, ethyl hydroxymethyl cellulose, ethyl hydroxyethyl cellulose. And various water-soluble polymers such as cellulose ethers such as carboxymethylcellulose, polyacrylamide, polyethylene oxide, polyvinyl alcohol, and casein. These can be used alone or in combination of two or more.

The setting regulator which can be used in the present invention has a function of controlling the curing time and the workable time, and includes sodium aluminate, sodium carbonate, sodium silicate, calcium aluminate, calcium sulfoaluminum. Various hardening accelerators such as citrate, potassium sulfate, aluminum sulfate and the like, and various hardening retardants such as citric acid, trisodium citrate, sugars, lactic acid and alcohols can be used.

As the shrinkage reducing agent that can be used in the present invention, those specified in JIS A6202 “Expanding material for concrete” can be used, and these can be used alone or in combination of two or more.

Next, the construction method of the present invention will be described.

In the construction method of the present invention, water is used in an amount of 2 parts by weight per 100 parts by weight of the cement mortar composition for adjusting unevenness.
5 to 55 parts by weight, preferably 30 to 50 parts by weight are added and kneaded, and the obtained kneaded material can be applied to a cement board. If the kneading water is less than 25 parts by weight, the kneaded material cannot be made uniform, or even if it can be made uniform, the viscosity is high and the workability deteriorates. On the other hand, when the amount exceeds 55 parts by weight, the kneading water becomes excessive and cracks are liable to occur, which may further reduce the strength. The degree of kneading when water is added to and kneaded with the composition may be uniform as long as it is well dispersed with water, but if a powdery polymer is used, kneading is preferably performed for 2 to 3 minutes. Hand mixer for kneading,
Use mixers such as Tarai mixer or brick iron,
Kneading can be performed by so-called hand kneading such as kneading.

The thickness of the kneaded material thus obtained when applied to a cement board subjected to joint treatment is preferably 4 mm or more. If the coating thickness is less than 4 mm, not only the step at the seam portion of the cement board and the like cannot be adjusted, but also fire prevention performance cannot be obtained. In applying the kneaded material, the kneaded material may be applied using a trowel, a spatula, or the like, or the kneaded material may be applied by spraying with a spraying machine or the like. In addition, when the cement mortar kneaded material is applied, it is preferable that a squeezing step be performed with a trowel, a brush, or the like. In addition, although one step increases the complexity, the step of applying the polymer specified in the present invention alone, diluted, or kneaded with cement or the like and applied as a primer can also be performed. Further, when finishing, it is preferable to level and harden using a surface leveling tool such as a trowel.

[0026]

The present invention will be described in more detail with reference to the following Examples and Comparative Examples.
It is not limited to the following embodiments.

In the examples, an example in which ordinary Portland cement is used as the cement will be described. Whichever one is used, an excellent non-adjustment cement mortar can be obtained as in the following examples. In the examples, "Delacrete cement board" which is a cement board manufactured by Mitsubishi Rayon Co., Ltd. was used as a base.

Examples 1 to 10 and Comparative Examples 1 to 18 Table 1 shows a composition obtained by using ordinary Portland cement as the cement and blending the same with the inorganic foamed aggregate, fiber and polymer in the amounts shown in Table 1. Add water at the indicated mixing ratio and add JI
The mixture was kneaded for 3 minutes using a mortar mixer specified in SR5201 to obtain various kneaded materials. In addition, the emulsion was dried at 105 ° C. to a constant weight at 105 ° C., and the solid content concentration was calculated from the weight before and after the drying using the following formula, and the polymer amount and the water amount from the values were as shown in Table 1. The amounts of the emulsion and the water to be added were determined.

Solid content concentration [wt%] = {weight after drying / weight before drying} × 100

Among the workability of the iron when the kneaded material was applied to a cement board with a thickness of 5 mm using an iron, the adhesion was evaluated.・ ・ ・: Good without spilling or peeling when applied to cement board. C: Spills, peeling off, etc. occurred when applied to a cement board.

Among the workability of the iron when the kneaded material was applied to the cement board with a thickness of 5 mm using an iron, the elongation of the iron was evaluated.・ ・ ・: The kneaded material spreads uniformly when applied to a cement board and has good quality. X: The kneaded material does not stretch uniformly when applied to a cement board.

When the kneaded material was applied to a cement board with a trowel so as to have a coating thickness of 5 mm, the iron workability was evaluated as the trowel workability.・ ・ ・: Good when the kneaded material does not adhere to the iron when applied to a cement board. X: The kneaded material adheres to the iron when applied to the cement board.

The thickness of the kneaded material applied to the cement board with a trowel was evaluated. ○ ・ ・ ・ Applicable to apply 4mm or more at a time even if it is applied by sweeping with a trowel, and the coating thickness can be controlled. ×: The coating thickness cannot be controlled more than 4 mm at a time even if the coating is performed with a trowel so that the coating thickness cannot be controlled.

The fire prevention performance was measured by applying the kneaded material to a cement board with a trowel, curing and curing the test specimen having the evaluated coating thickness.
Heating was carried out according to a fire prevention class 2 heating curve specified in IS A 1301.・ ・ ・: The maximum back surface temperature is 260 ° C. or less. ×: The maximum back surface temperature exceeds 260 ° C.

The surface properties of the cured product evaluation were as follows. The kneaded material was applied to a cement board by a trowel so as to have a coating thickness of 5 mm, and the test pieces evaluated for trowel workability were cured and cured, and cured after 1 day and 28 days. The body surface was visually observed and evaluated.・ ・ ・: Good without cracks, efflorescence, peeling, and without fiber protrusion. ×: Cracks, efflorescence, peeling, and fibers jumping out.

As for the overall evaluation, those in which all items were ○ were evaluated as 総 合, and those in which any item was と し た were evaluated as ×.

[0037]

[Table 1]

In Table 1, in the column of the inorganic foamed aggregate,-is not added, a is obsidian pearlite, and the particle size distribution is as shown in Table 1.
It was adjusted as described, and was obtained by mixing "Asano Perlite No. 3,""Asano Perlite No. 4," and "Asano Perlite No. 5" manufactured by Taiheiyo Cement Corporation.
b is obsidian pearlite adjusted to have a particle size distribution as shown in Table 1, manufactured by Fuyo Perlite Co., Ltd., "Fuyolite 0", "Fuyolite 1", "Fuyolite 2", "Fuyolite 7" Was mixed. Is shown. In the column of particle size, the ratio (% by weight) remaining on the sieve of each opening is described.

In the fiber column,-indicates no addition, A indicates nylon fiber, B indicates vinylon fiber, and C indicates alkali-resistant glass fiber.

In the polymer column,-represents no addition, and X represents "NS Hyflex HF-1000" manufactured by Nippon Kasei Co., Ltd., which is an ethylene-vinyl acetate copolymer emulsion polymer.
Y is "Erotex AP-200" manufactured by NSC, which is a vinyl acetate / vinyl versate / acrylic acid copolymer powder polymer; Z is "Crosslen CM" manufactured by Takeda Pharmaceutical Company, which is a styrene / butadiene copolymer latex.
X-02 ".

Since Examples 1 to 10 were tested under the conditions satisfying the requirements of the present invention, good coating performance was obtained and good cured products were obtained. In Comparative Example 1, since no inorganic foamed aggregate was added, it was not possible to apply 4 mm or more at a time, it was difficult to control the applied thickness at the time of construction, fire prevention performance was not obtained, and the surface after curing was cracked. It was observed. In Comparative Example 2, since the inorganic foamed aggregate exceeded 60 parts by weight,
Poor adhesion to substrate, cracking or peeling after curing. In Comparative Examples 3 and 4, the percentage of the inorganic foamed aggregate remaining on the sieve having an opening of 2.36 mm was 0.1% by weight.
Less than 4mm at a time,
It is difficult to control the coating thickness at the time of construction, and fire prevention performance cannot be obtained. Further, in Comparative Example 4, the workability is reduced because the ratio of the inorganic foam aggregate remaining on the sieve having a mesh size of 0.60 mm is 50% by weight or more. In Comparative Example 5, the proportion of the inorganic foam aggregate remaining on a sieve having a mesh size of 2.36 mm was more than 2% by weight. Irregularities occurred on the surface of the body. In Comparative Example 6, cracks occurred on the surface of the cured product because no fiber was added. Comparative Example 7 has a large amount of fiber, so that the adhesion to the base and the elongation of the iron are reduced.
In addition, the fibers jump out to the surface of the cured product, and the surface property is reduced.
In Comparative Example 8, since no polymer was added, the workability of ironing to the substrate and the elongation of the iron decreased, and the surface of the cured product was reduced due to uneven iron. In Comparative Example 9, since the addition amount of the polymer exceeded 10 parts by weight, the viscosity of the kneaded material was increased, and among the iron workability, the elongation of the iron and the separation of the iron were reduced, and it became difficult to apply the iron. Occurred. In Comparative Example 10, since the amount of kneading water was smaller than the specified amount, the kneaded material became hard, the workability was poor, and the cured product had irregularities.
In Comparative Example 11, since the amount of the kneading water was larger than the specified amount, it was difficult to apply 4 mm or more at one time, it was difficult to control the coating thickness at the time of construction, and fire prevention performance was not obtained. occured. In Comparative Example 12, the inorganic foamed aggregate had a particle size of 5 m.
m, the surface of the cured product becomes uneven, and the surface properties are reduced.

[0042]

The present invention has the following effects. Applying or spraying the cement mortar composition on the cement board to smooth the surface, it is possible to apply 4 mm or more at a time, so the cement board warps or adjusts the level difference at seams etc. It is possible to control the coating thickness at the time of construction without providing a special process, to obtain fire prevention performance, and to greatly improve workability.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI theme coat ゛ (reference) C04B 26:02)

Claims (3)

[Claims] A cement mortar for adjusting land use which is used in a construction method in which a cement board is attached to a wooden structure, a steel frame structure or the like, then jointed, treated with cement mortar, and finished with a finishing material. 100 parts by weight of cement, 10 to 60 parts by weight of inorganic foam aggregate, 0.1 to 2 fibers
A cement mortar composition for adjusting unevenness, which is adjusted to a range of 0 part by weight and 1 to 10 parts by weight of a polymer. 2. An inorganic foamed aggregate having a particle size of 5 mm or less and a ratio of 0.1 to 2% by weight remaining on a sieve having a mesh size of 2.36 mm and a mesh size of 1.18 mm. The proportion of the substance remaining on the sieve is 15 to 25% by weight, and the proportion of the substance remaining on the sieve having an aperture of 0.60 mm is 50% by weight.
The cement mortar composition for uneven land adjustment according to claim 1, which is: 3. A cement mortar composition for adjusting unevenness 10
A kneaded material obtained by kneading 25 to 55 parts by weight of water with respect to 0 parts by weight was added to a cement board having been subjected to joint treatment by 4 mm.
The method for applying a cement mortar composition for uneven land adjustment according to claim 1 or 2, wherein the composition is cured by applying and curing the composition.