JPS632994B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a building material composition used for plastering or painting as a decorative top coating material for walls, ceilings, floors, etc. of buildings.

BACKGROUND TECHNOLOGY AND PROBLEMS TO BE SOLVED Traditionally, for example, decorative topcoating materials used in plastering work include aggregates such as silica sand, mica, perlite, vermiculite, and calcium carbonate, inorganic and organic fibers, colorants, and adhesives. Mixtures containing glue and the like are used, and when used, these are kneaded with water or synthetic resin emulsion, and applied by troweling, spraying, etc. However, the curing of these top coat materials is due to natural evaporation of water, so even if the coated surface is not fully cured, it is still in a sufficiently stable state, which means that it is possible to proceed to the next process such as electrical or gas work. It usually takes several days to complete the construction, and this period is particularly long during the winter and rainy seasons, extending the total number of construction days accordingly.

Furthermore, before the painted surface dries and hardens, when it becomes soft, people or objects may accidentally come into contact with the painted surface and damage it, and if it comes into contact with water, the affected area will be washed away, requiring repair or repainting.

The present invention irreversibly produces an elastic water-containing gel within a few hours after application of water-based topcoats for plastering or painting of walls, ceilings, floors, etc., and therefore before completely curing. Even if an object touches it, it will not stick to it,
We have created a building material composition for top coating that returns to its original state due to its elasticity even if it is deformed by an object, reaches a stable state where the painted surface is not damaged, and allows the next construction work to be started within a few hours. The challenge is to provide.

Solution The object of the invention is solved by adding a hydrophilic urethane prepolymer to known aqueous topcoats.

That is, the present invention provides the aqueous top-coat building material composition, which contains a filler and its binder as essential components and also contains a hydrophilic urethane prepolymer.

Detailed Discussion The hydrophilic urethane prepolymers used in the present invention are urethane prepolymers that dissolve or disperse in water. As is well known, urethane prepolymers have unreacted free isocyanate groups at the molecular ends, and react with active hydrogen compounds to extend the chain and/or crosslink to form polyurethanes. A type of active hydrogen compound in water, which reacts with the free isocyanate group to form a urea bond, resulting in chain extension and/or
or crosslink. At this time, if the urethane prepolymer itself is dissolved or uniformly dispersed in water, it will react with some of the water to cause chain extension and/or crosslinking as described above, and at the same time, the water in the system will be transferred into the polyurethane matrix. Incorporated into an elastic water-containing gel. Once formed, the hydrogel is chemically and physically stable and is not destroyed by even significant mechanical shock. Therefore, when this hydrophilic urethane prepolymer is added to the above-mentioned construction material composition for top coating and kneaded with water for construction, the painted surface gels within at least a few hours, and even if the next construction is restarted, there is no problem. It will be in a stable state without any problems.

Such hydrophilic polyurethane is made by combining a polyisocyanate compound and a polyether polyol.
Excess of the former relative to the latter, i.e. NCO/OH
It can be obtained by reacting in a conventional manner such that the ratio of the two is at least 2 or more. As the polyisocyanate compound, tolylene diisocyanate, xylylene diisocyanate, 4,4'-diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, water-added 4,4'-diphenylmethane diisocyanate, etc. are used. As the polyether polyol, a polyether diol obtained by using a dihydric alcohol such as ethylene glycol as a starting material and adding ethylene oxide alone or other alkylene oxide to this in the form of a random or block copolymer is used. It will be done.
Polyether polyols obtained by using trihydric or higher alcohols such as glycerin pentaerythritol, sorbitol, etc. as starting materials instead of dihydric alcohols can also be used alone or in combination with polyether diols.

In order for a urethane prepolymer to be water-soluble or water-dispersible, the hydrophilic block ethylene oxide units must account for at least 20% of the total alkylene oxide content. Furthermore, if the polyether polyol is excessively hydrophilic, the water resistance of the final coating film will be reduced, so it is preferable to contain a hydrophobic block in an appropriate proportion. For the same reason, the molecular weight of polyether polyol is OH1
The number is preferably 400 to 4000 per piece. Considering water dispersibility, film forming properties, workability, etc., the weight ratio of ethylene oxide and propylene oxide is
Molecular weight 800-8000 in the range 20:80-90:10
Particularly preferred are polyoxyethylene polyoxypropylene glycols.

The hydrophilic urethane prepolymer can be used as is or diluted with a solvent that does not react with isocyanate groups, such as acetone, methyl ethyl ketone, or propyl carbonate, stored in a separate container from the rest of the ingredients, and mixed on site before use and kneaded with water. It is preferable to carry out construction.

Filler includes aggregate, such as perlite, permiculite, ceramic powder, calcium carbonate,
These include clay, bentonite, alumina, mica, anhydrite, silica sand, diatomaceous earth, and slag.

For decorative wall materials, inorganic or organic fibers or pulverized materials can be used as fillers. These are crushed valve, human silk powder, cotton powder, human silk thread, cotton thread,
Examples include wool, synthetic fibers, asbestos, rock wool, glass wool, cellophane, rubber, plastic, and crushed wood. The coloring material may also include colored versions of the above materials, metal powder, pigments, or dyes.

The binder includes a viscosity modifier and is generally a water-soluble glue. CMC, hydroxymethylcellulose, methylcellulose, water-dispersible powder resin, synthetic resin emulsion, etc. are used.

All other components conventionally used in aqueous top-coat building material compositions can be used, and their types, blending ratios, etc. can be arbitrarily adjusted according to the purpose of use by conventional methods.

The amount of hydrophilic urethane prepolymer used according to the invention depends on the amount of water (including water in the synthetic resin emulsion) used for kneading. i.e. water volume
It is preferred to use at least 5 parts by weight of urethane prepolymer per 100 parts, the upper limit being determined primarily by economic considerations.

At the time of construction, conventional methods can be followed except for adding extra hydrophilic urethane prepolymer. That is, the urethane prepolymer, water, and the remaining components are thoroughly kneaded, the top coat is applied to the construction surface using a trowel, a spray gun, a roller, etc., and the mixture is allowed to naturally harden and dry. At this time, the painted surface gels and becomes stable within at least a few hours after application, and the painted surface can even be touched. Further, in order to adjust the time required to reach this state and the workable time, a retardant such as an acid or an accelerator such as an alkali may be used as the case requires.

The final coating film has greater elasticity, hardness, and water resistance than conventional top coating materials that do not contain urethane prepolymers. It also has good adhesion to the base.

Examples of the present invention are shown below. Examples and percentages are by weight.

Production Example of Hydrophilic Urethane Prepolymer 1 Ethylene oxide was addition-polymerized to ethylene glycol in a conventional manner to obtain a diol having an average molecular weight of 2000. 792 parts by weight of this diol and tolylene diisocyanate (2.4-; 2.6-isomer ratio 80:
20) 208 parts by weight were reacted at 90°C in a nitrogen stream for 3 hours to obtain a prepolymer.

It is uniformly dispersed in water and forms an elastic hydrated gel at a concentration of 5% or more.

Production Example 2 A diol having an average molecular weight of 3000 was obtained by addition polymerizing ethylene oxide and propylene oxide to diethylene glycol in the form of a block using a conventional method. The weight ratio of ethylene oxide and propylene oxide at this time was 80:20. Diol obtained
800 parts by weight and 200 parts metaxylylene diisocyanate
Parts by weight were reacted at 90° C. for 4 hours in a nitrogen stream to obtain a prepolymer.

It disperses uniformly in water and forms an elastic hydrated gel at concentrations above 10%.

Production Example 3 Ethylene oxide and propylene oxide were randomly added to trimethylolpropane in a conventional manner to obtain a triol having an average molecular weight of 4000.
The weight ratio of ethylene oxide and propylene oxide at this time was 90:10. This triol
827 parts by weight and 173 parts by weight of hexamethylene diisocyanate
Parts by weight were reacted at 70° C. for 6 hours in a nitrogen stream to obtain a prepolymer.

It dissolves uniformly in water and forms a hydrated gel at concentrations of 10% or more.

Composition and construction examples 1 Composition Pulverized pulp 100 parts Wood flour colored blue 65 parts Cellophane cut pieces dyed black 5 parts Carboxymethyl cellulose soda salt 20 parts Pre-mixed prepolymer aqueous solution 1500 parts Polymer aqueous solution: 1300 parts of water: Prepolymer
200 copies) After mixing these ingredients well, use a trowel to apply the gypsum plaster on the wall surface evenly, and apply 5 coats.
After a period of time, a beautiful painted surface with black spots scattered in a pale blue color was obtained, which had excellent initial strength and did not move even when pressed with a finger. In addition, even after 24 hours had elapsed on walls that were simultaneously applied using the same composition and kneaded with only water without using a prepolymer, there remained areas where the painted surface moved when pressed with a finger. We were able to obtain initial strength more than twice as quickly. Furthermore, the wall surface using the prepolymer has excellent adhesive strength, and a water-resistant wall surface that does not wash away even when water is poured on it was obtained.

Example 2 Composition Juraku colored silica sand (20-100 mesh)
100 parts carboxymethylcellulose soda salt 1 part water 30 parts prepolymer 15 parts These compositions were mixed well and applied to a flat mortar surface using a trowel. After 2 hours, the performance as described in Example 1 was observed. We obtained a beautiful sand wall in the color of Juraku.

Example 3 Composition: 100 parts of agarstone of 20-60 mesh. 10 parts of crushed black slag of 18-48 mesh. After 4 hours of smoothing with a trowel, an elastic, granite-like hardened paint surface was obtained, and the paint surface was not damaged even when lightly walked on, allowing the next painting process to proceed. was completed.

Example 4 Composition 12-32 mesh granular rock wool 30 parts 60-200 mesh pulverized cotton 5 parts clay 65 parts titanium oxide 1 part iron yellow 0.1 part polyvinyl alcohol 1 part carboxymethylcellulose 2 parts water 150 parts prepolymer 30 parts these After mixing the mixture well, it was sprayed onto the concrete ceiling surface using a ricing gun, and after 2 hours, a coated surface with excellent initial strength was obtained that did not move even when touched with a finger. After another 24 hours, a beautiful white uneven ceiling surface with excellent adhesiveness and water resistance was obtained.

Example 5 Composition White wool yarn cut to 5 m/m 30 parts Vinylon Amagori (brown) cut to 5 m/m
70 parts carboxymethyl cellulose soda salt 20 parts water 400 parts prepolymer 800 parts After mixing these ingredients well, I painted the upper wall with a trowel.After 6 hours, there was no movement of the painted surface even when I touched it with my finger. A beautiful camel-colored and white cotton wall with excellent initial strength was obtained.

Example 6 Composition 32-100 mesh 50 parts heavy calcium carbonate powder 40 parts light calcium carbonate powder 20 parts titanium oxide 10 parts phthalocyanine blue dispersed in water 0.1 part pigment dispersant 0.1 part hydroxymethyl cellulose 1 part water 50 parts above The composition is thoroughly mixed with a mixer to form a paint.

After adding 120 parts of prepolymer to 100 parts of this paint compound and mixing well, I painted it on the mortar wall surface with a roller brush and after 1 hour, there was no movement of the painted surface when I touched it with my finger, and it did not wash away even when I poured water on it. A beautiful white ricin-like painted surface was obtained.

Example 7 Composition White Portland cement 100 parts 48-200 mesh silica sand 150 parts colorless chromium pigment 10 parts Soluble starch 0.5 parts Water 30 parts Prepolymer 30 parts After the above composition was mixed well, it was poured onto a concrete floor surface and troweled. After 3 hours of smoothing and smoothing, an elastic green hardened floor surface was obtained, and the next painting work could be carried out without damaging the painted surface even when walking lightly on it.

A synthetic resin emulsion may be added to the compositions of Examples 1 to 7 as necessary.

Synthetic resin emulsions include vinyl acetate resin emulsion, ethylene-vinyl acetate resin emulsion, synthetic rubber emulsion, vinyl acetate-acrylic acid ester copolymer resin emulsion, styrene-acrylic acid ester copolymer resin emulsion, acrylic acid ester copolymer resin emulsion, etc. It is.

Effects (i) The initial strength is developed quickly, and the painted surface is not damaged by electricity, gas, etc. construction work.

(ii) Even if water is applied once initial strength has been developed, the coated surface will not run off and a water-resistant coated surface can be obtained.

(iii) Curing time can be controlled.

(iv) It is possible to control the physical properties of the film, such as hard or elastic films.

Claims (1)

[Scope of Claims] 1. A polyether polyol component containing a filler and its binder as an essential component and containing at least 20% by weight of ethylene oxide units based on the total alkylene oxide content, and a polyisocyanate compound in excess of the equivalent amount thereof. Contains a water-soluble or water-dispersible urethane prepolymer that irreversibly forms a hydrogel in the presence of water, obtained by reacting with An aqueous building material composition characterized in that it is used as a water-based building material composition. 2. The building material composition according to item 1, wherein the filler is an inorganic or organic fibrous material. 3. The building material composition according to item 1, wherein the filler is an inorganic pulverized material such as minerals, slag, cement, metal powder, etc. or an organic pulverized material such as rubber, plastic, wood, etc. 4. The building material composition according to any one of Items 1 to 3, wherein the binder is a glue and/or a synthetic resin emulsion. 5. The building material composition according to any one of Items 1 to 4, wherein the urethane prepolymer and the remaining components are stored in separate containers before use, and upon use, are mixed on site and kneaded with water for construction.