JPH0384086A - Gap-finishing structure - Google Patents

Abstract

PURPOSE:To obtain the subject structure having excellent initial compression strength, curable within a relatively short period, imparted with water-proofing property and resistant to the generation of thinning by coating a gypsum putty with a water-proofing sealant containing a mineral spirit as a solvent. CONSTITUTION:A gypsum putty filled in a gap of a structure is cured e.g. by leaving standing for <=1 day at normal temperature. A water-proofing sealer composed of a (meth)acrylate copolymer resin having an average molecular weight of preferably 80,000-120,000 and containing a mineral spirit as a solvent is applied at a rate of 150-250g/m<2> to the surface of the cured putty and the surrounding base.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a gap finishing structure in which gaps in structures such as floors, walls, and ceilings are filled and finished with gypsum putty.

[Conventional technology]

Generally, floor finishing methods involve pouring slurry-like mortar onto an uneven floor surface and taking advantage of the natural flow and flattening properties of the slurry to create a smooth floor surface. The finished structure thus obtained has the advantage of being excellent in initial compressive strength and compressive strength when wet with water (durability of compressive strength). However, mortar is made by mixing sand and portland cement with water, so
It has disadvantages such as a volume reduction (so-called "thinness") during curing and a long curing time (for example, curing time of 24 hours or more).

When "sagging" occurs, steps become noticeable and it is not possible to create a smooth floor surface.

A finishing structure using gypsum putty was considered to overcome all of the above-mentioned drawbacks.

Gypsum putty is a hydraulic putty whose main component is calcium sulfate, and due to the hydration of calcium sulfate,
It hardens over time and does not "thin" during hardening.

[Problem to be solved by the invention]

However, finished structures using gypsum-based putty have the problem that the cured product of the putty absorbs water when wet, resulting in a decrease in compressive strength and adhesion strength to the subfloor material. In other words, when a cured product of gypsum putty gets wet with water, it tends to crumble and unevenness cannot be resolved.

Therefore, it is an object of this invention to provide a gap finishing structure that uses a gypsum putty that is less prone to "sagging", has excellent initial compressive strength, and has a relatively short curing time, and is also waterproof. .

[Means to solve the problem]

In order to solve the above problems, the gap finishing structure according to the present invention is characterized in that a waterproof sealer using mineral spirit as a solvent is applied on top of the gypsum putty that fills the gaps in the structure. do.

The gap finishing structure of the present invention is applicable to floors, walls, ceilings, etc. of buildings such as houses, and is not particularly limited.

In such areas, gaps (including depressions caused by steps) are formed between base materials and surface finishing materials. The goal is to fill in these gaps and create a finish that does not create any unevenness (steps) or make them noticeable.
First, fill in the gaps with gypsum putty.

Any type of gypsum putty may be used in the present invention, and for example, the following may be used. A base material is α-type hemihydrate gypsum with a particle size in the range of 0 to 297μ and a bulk specific gravity of 0.7 or more, and a filler (for example, calcium carbonate, etc.) and an adhesive are applied to this base material. agents (e.g. starch, PV
A, etc.), viscosity modifiers (e.g., methyl cellulose, etc.), coagulation modifiers (e.g., citrates, etc.), and colorants (e.g., iron oxide, etc.).
An undercoat putty is used in which a predetermined amount of hollow spherical lightweight aggregate is mixed in, and if necessary, a predetermined amount of hollow spherical lightweight aggregate is mixed in.

The gap is filled with the gypsum putty to make the surface smooth (preferably flat). This can be done by pouring the putty into the gap and letting it flow naturally;
Alternatively, it may be done forcibly, and there are no particular limitations on the method of smoothing the surface.

The embedded gypsum putty is left to harden, for example, at room temperature for one day or less. It is also possible to make the surface smooth as described above by polishing or scraping the surface of the cured gypsum putty.

Thereafter, a waterproof sealer is applied at least over the cured product of the gypsum putty, preferably over the cured product and the surrounding substrate. The coating amount is not particularly limited, but is preferably 150 to 250 g/g, for example. If the amount of waterproof sealer applied is outside this range, there is a risk of a decrease in compressive strength when wet.

As the waterproof sealer, main Nera 7L/
There are no particular limitations as long as spirit (kerosene-based) is used, and examples of use include (meth)acrylic homopolymer resin sealers, (meth)acrylic copolymer resin sealers, epoxy resin sealers, urethane resin sealers, etc. The former two are preferable to the latter two in terms of cost and low cost. Among these, it is preferable to use a (meth)acrylic copolymer resin sealer. The use of a (meth)acrylic copolymer resin sealer has the advantage of further improving water resistance.

The (meth)acrylic copolymer resin comprises a (meth)acrylic monomer and a vinyl monomer copolymerizable with the same monomer [
(excluding (meth)acrylic monomers).

Examples of the (meth)acrylic monomer include acrylic acid, methacrylic acid, esters of both, acrylamide, methacrylamide, acrylonitrile,
Examples include methacrylonitrile, and one or more of them may be used. (For methacrylic acid esters,
For example, methyl, ethyl, n-propyl, 1so-propyl, n-butyl, 1so-butyl, 5ec-butyl,
Examples include esters such as amyl, hexyl, heptyl, octyl, 2-ethylhexyl, nonyl, oxononyl, decyl, and oxodecyl. These may be used alone or in combination.

Examples of the vinyl monomers (excluding (meth)acrylic monomers) include ethylene, vinyl acetate, vinyl propionate, vinyl chloride, vinylidene chloride, styrene, butadiene, crotonic acid, itaconic acid, and esters thereof. can be exemplified.

The ratio of monomers for copolymerization is not particularly limited.

The average molecular weight of the (meth)acrylic copolymer resin is also not particularly limited, but is preferably in the range of 80,000 to 120,000, for example. Outside this range, there is a risk that the permeability effect will be reduced.

Three or more of the above monomers may be copolymerized to form a multicomponent copolymer, and the polymerization mode may be alternating copolymerization or random copolymerization. It may be. The obtained copolymer resin alone or in combination is dissolved in a solvent.

(Meth) The blending ratio of the acrylic copolymer resin and the solvent is preferably 20% to 40% (weight ratio) of the copolymer resin to 100% of the solvent or 100% of both. However, if the copolymer resin content is less than 20%, water resistance may decrease, and
If it exceeds 0%, there is a risk that the permeability effect will decrease.

In addition to the (meth)acrylic copolymer resin and the solvent, the (meth)acrylic copolymer resin sealer may contain other components as necessary.

Mineral spirit is used as a solvent for the (meth)acrylic copolymer resin sealer. If a solvent other than mineral spirit is used, such as water, there is a problem in that the compressive strength of the gypsum putty decreases, and if an organic solvent other than mineral spirit is used, a binder (such as , ethylene vinyl acetate resin) can be melted by solvents, reducing the strength of the plaster itself and harming the health of workers.

In addition, there are not only solvent-type sealers but also emulsion-type sealers, but emulsion-type sealers are
There is a problem that the strength does not increase because the permeability to the putty material is low.

The (meth)acrylic copolymer resin sealer may be applied manually using a brush, hand roller, etc., or by using a machine such as a spray gun, caulking gun, flow gun, roll spreader, etc. There are no particular limitations on the coating method.

The gap finishing structure obtained in the above manner has no unevenness or is hardly noticeable;
Even when wet with water, the decrease in compressive strength is small, and the initial compressive strength is also good.

In the above explanation, the gypsum putty was prevented from getting wet from the front side, but if moisture is expected to approach the gypsum putty from the back side (base side), Alternatively, the waterproof sealer may be applied in advance to the gaps in the structure, and then filled with gypsum putty.

In this way, deterioration due to moisture from the back side can also be prevented.

[For production]

By applying a waterproof sealer using mineral spirits as a solvent, at least on top of the gypsum putty,
The putty can be prevented from getting wet, and deterioration of the putty due to getting wet can be prevented.

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to the drawings showing embodiments thereof.

FIG. 1 shows one embodiment of the gap finishing structure of the present invention applied to a floor. As seen in Figure 1 (al), a floor panel 3 is laid on the joists 2 that are passed between the flooring l. A gap 4 is formed between the floor panels 3. If the cushion floor (
CF) If you lay out a sheet (or carpet, etc.) 5,
They appear as steps or depressions on the seat 5, impairing the viewing area and impeding walking, installing furniture, etc.

Therefore, the gap 4 is filled with gypsum putty 6, and the surface of the gypsum putty 6 is smoothed. As shown in FIG. 1 (bl), a waterproof sealer is applied on the surface of this gypsum putty 6, preferably from the surface of the gypsum putty 6 to the surface of the floor panel 3, and a waterproof sealer film 7 is applied. Make sure to cover it.

This eliminates the gap 4 and prevents the gypsum putty 6 from getting wet. By covering it with the sheet 5, the gap 4 becomes less noticeable. Alternatively, Figure 1 (C)
As shown in the figure, even when a gap 4 is created between floor panels 3 due to a step difference, the gap finishing structure can be applied in the same manner as described above.

FIG. 1 shows an example in which the gap finishing structure of the present invention is applied to a floor with the ground below. FIG. 2 is an example of the application of the gap finishing structure of the present invention to floors on the second and higher floors. As shown in Figure 2,
In this second floor, a second floor panel 13 is laid on a second floor side drawer 12 attached to a steel beam 11. The second-story floor panels 13 are laid from both ends, and the last two panels are pushed in to make them flat. Between the adjacent second floor panels 13,
If the gap 4 as explained in FIG. 1 occurs,
The gap finishing structure of the present invention can be applied as described above. FIGS. 3 and 4 show an example of applying the gap finishing structure of the present invention to an outer peripheral wall panel. As shown in Fig. 3, when a plurality of outer peripheral wall panels 21 are installed, if a gap or gap 4 due to a step occurs between adjacent panels 21, please do as described above. , the gap finishing structure of this invention can be applied. As shown in FIG. 4, when a gap 4 occurs between the outer wall panel 21 and the outer wall subframe 22 or pillar 23, the gap finishing structure of the present invention is applied as described above. can do.

Note that the gap finishing structure of the present invention is not limited to the above embodiments. For example, it can be applied to fill in gaps created by cracks, cave-ins, falls, etc. after a structure is completed.

Specific examples and comparative examples of the present invention are shown below, but the present invention is not limited to the following examples. Note that, hereinafter, "parts by weight" will simply be expressed as "parts".

Example - 100 parts of Panahome Cross Putty (manufactured by National Housing Industry Co., Ltd.) for undercoating was combined with 40 parts of water and thoroughly kneaded to prepare a gypsum putty.

This putty was poured into a mold of 20 m x 20 ts x 2 Qm, cured indoors for 2 days, and then dried in a drying layer at 45°C for 1 day. Thereafter, the mold was removed to obtain a cured gypsum putty. This gypsum putty requires 180 minutes to completely harden, and you can walk on it 30 minutes after applying the putty. On the other hand, in the case of mortar construction, the elapsed time during which walking is possible is 8 hours or more.

The obtained cured gypsum putty was immersed in the (meth)acrylic copolymer resin sealer shown below for 1 hour, and then 2
It was air-dried indoors for several days and used as a test piece.

(Meth)acrylic sea component blend: (meth)acrylic copolymer resin (molecular weight Mw
=100,000±10,000) by dissolving 24 parts in 76 parts of mineral spirit.

Appearance: Colorless and transparent Non-volatile content = 23±1% Viscosity: 100-500cP (I degree 25℃) Specific gravity:
0.87±0.1 (Temperature 25°C) - Comparative Example 1 - A cured product of the same gypsum putty used in the above example was immersed in the following water-based sealer for 1 hour, and then treated in the same manner as in the example. A test piece was obtained.

This two-component blended acrylic copolymer resin (MMA: BA (butyl acrylate) = 7:3, molecular weight 300,000 to 600,000, particle size 0.
05~0. In) -23 parts Additives [ethylene glycol, film-forming aid (Hensyl alcohol)]...2 parts Water (solvent)...75 parts Appearance: Milky white emulsion Solid content: 23 parts 1% A comparative example 2 Test pieces of Examples and Comparative Examples, which were made from the same cured gypsum putty used in the above Examples without applying a sealer, were placed in water at 20°C for 1 hour, 3 hours, and 5 hours. The samples were immersed for 24 hours, and the water absorption and compressive strength were measured for each immersion time. The results are shown in Table 1.

As shown in Table 1, even when the test pieces of the examples were in contact with water for a long time, the water absorption rate was lower than that of the comparative examples, and the decrease in compressive strength was small.

〔Effect of the invention〕

As described above, the gap finishing structure according to the present invention is characterized in that a waterproof sealer using mineral spirits as a solvent is applied on top of the gypsum putty that fills the gaps in the structure. Therefore, the gypsum putty is protected from water by the waterproof sealer, and the compressive strength, especially when wet, is less likely to decrease.

In this invention, as the waterproof sealer (meth)
Using an acrylic copolymer resin sealer also has the effect of reducing solvent odor.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing one embodiment of the gap finishing structure according to the present invention, Fig. 2 is a schematic diagram showing one example of floor assembly, and Figs. 3 and 4 are respective examples of wall assembly. FIG.

Claims (1)

[Claims] 1. A gap finishing structure in which gaps in a structure are filled and finished with gypsum putty, characterized in that a waterproof sealer using mineral spirit as a solvent is applied on top of the gypsum putty. Gap finishing structure. 2. The gap finishing structure according to claim 1, wherein the waterproof sealer is a (meth)acrylic copolymer resin sealer.