JPH08245986A - Method for cleaning surface of exterior finishing material and cleaning liquid used therefor - Google Patents

Abstract

PURPOSE: To effectively dissolve and remove stain attached to the surface of an exterior finishing material without damaging the surface layer to which a ground such as mortar joint and glaze are applied by applying a cleaning liquid consisting essentially of a neutral ammonium hydrogenfluoride. CONSTITUTION: This method for cleaning the surface of an exterior material comprises using a cleaning liquid consisting essentially of (A) neutral ammonium hydrogenfluoride of the formula, NH4 F, and preferably further containing (B) approximately 5 to 10% of a cationic, amphoteric, nonionic or anionic surfactant, (C) an alkali agent such as (aqueous) ammonia and (D) a thickener such as sodium alginate or a binder, etc., as blending materials. Furthermore, the component (A) is obtained by blowing ammonia (NH3 ) gas into hydrofluoric acid (HF) to absorb NH3 gas into HF, and is prepared as an aqueous solution having pH7-8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for cleaning a surface of an exterior material and a cleaning liquid used therefor, and in particular, a glaze is applied to the surface for the purpose of improving gloss, protecting the surface, or decorating. The present invention relates to a cleaning technique capable of effectively removing stains attached to the surface of exterior materials such as wall tiles that have been applied without damaging the base material such as mortar joints and the surface layer of the exterior material.

[0002]

2. Description of the Related Art Exterior materials are used for ordinary houses, downtown buildings,
It is used as a wall surface of expressways. The exterior material
Is easily exposed to exhaust gas, earth and sand, rainwater, etc.
Is a carbon component caused by exhaust gas and S caused by earth and sand
iO₂It contains a lot of ingredients and other
The various constituents are included to form a contaminated composition. Cause
In addition, on the walls of expressways and the walls of buildings in central Tokyo
The contaminated constituents are as follows.Highway city center building Carbon (exhaust gas) 42% 15% SiO₂(Earth and sand) 31% 68% Al (Soil and sand) 3% 7% Ca (water stain) 4% 4% K (water stain) 1% 1% S (exhaust gas) 3% 1% Hydrocarbon (oil) 9% 3%Iron (iron powder rust) 7% 1% And, these dirt attachment forms are complicatedly intertwined.
Pollutants in the atmosphere, moisture in the atmosphere, moisture in rainfall
Combined with and adhered to the exterior material as strong composite dirt.
It If such dirt is left unattended, it will corrode the exterior materials.
Not only does it damage the appearance. Such dirt
Conventionally, various cleaning liquids have been used to remove dirt.
Comes, cleaning solutions using various surfactants, fluorinated water
Elementary (hydrofluoric acid, HF) liquid, acidic ammonium fluoride (N
H_Four(F / HF) liquid is used, but cleaning is not
Aesthetics, even if sufficient or effective for cleaning
Drop or deteriorate the gloss of the surface
In the present situation, there are few things that are completely satisfactory.
is there. In particular, the problem is that such exterior materials are
There are surface finish and non-glaze, while gloss
For the purpose of top, surface protection or decoration, glaze on the surface
There are a lot of things that have been glazed
Is. For example, applying glaze to a non-metallic porous clay substrate
There are various kinds of iron, precious metals, light metals, etc.
Glazed metal is applied to the metal compact base material. The glaze (wow)
Various materials are used for the gris, for example, the general formula
RO / xR₂O₃・ YR₂Represented by O, a type of glass,
Cali (K₂O, soda (Na₂A base (RO) such as O),
Alumina (Al₂O₃), Boric acid (B₂O₃) Etc. R₂O₃Success
Minutes, silicic acid (SiO₂) Etc. R₂Proper ratio with O component
For example, a compound composed of x: y = 1: 10 is used
Is done. An ultrathin metal layer is used for the glaze.
In some cases, glass products are subject to heat rays.
Special metal on the surface of the transparent glass plate to enhance the blocking effect
Or heat ray reflection glass with a layer of metal oxide fixed
Color burned with glaze on the surface of glass and polished plate
There is also a glass. Glaze (wow) on the surface
When the exterior material that has been glazed) is placed in the environment
In order to dissolve and remove the dirt on the surface,
Rough surface finish when using (hydrofluoric acid, HF)
Glazed or non-glazed is fine, but glaze on the surface
If the medicine (wow glaze) is applied,
Often damages the base material and the surface layer, while hydrogen fluoride
Ammonium fluoride ammonium fluoride (NH_FourF ・
Even if HF) is used, it depends on the concentration.
After all, the base material and the surface layer with glaze applied
Often hurt.

[0003]

SUMMARY OF THE INVENTION The present invention is intended to solve the above problems. Other objects and novel features of the present invention will be apparent from the entire description of the present specification.

[0004]

According to the present invention, a cleaning solution containing neutral ammonium hydrogen fluoride represented by the chemical formula NH ₄ F as an essential component, preferably neutral ammonium hydrogen fluoride, is used on the surface of an exterior material on which dirt is attached. And a surface-active agent, more preferably a coating solution comprising a thickening agent and an alkaline substance is applied to the exterior material surface cleaning method characterized by dissolving and removing dirt adhering to the exterior material surface, The present invention also relates to the cleaning liquid for cleaning the exterior material surface.

The neutral ammonium hydrogen fluoride used in the present invention has the chemical formula NH ₄ F. When ammonia (NH ₃ ) gas is blown into and absorbed by hydrofluoric acid (HF), ammonium fluoride (NH ₄ F) is generated, and when an equivalent amount of hydrofluoric acid (HF) is added thereto, acidic fluorination is performed. Ammon (NH ₄ F · HF) is obtained. Neutral ammonium hydrogen fluoride (NH ₄ F) can be obtained, for example, in the production process. The neutral ammonium hydrogen fluoride is formed as an aqueous solution having Ph of 7 to 8, for example.
The neutral ammonium hydrogen fluoride can be used alone. You may dilute with water, a solvent, etc. suitably according to a use etc.

[0006] Neutral ammonium hydrogen fluoride is preferably mixed with a surfactant to form a detergent composition.
When cleaning the wall surface of tiles or the like, the cleaning solution tends to drip with the neutral ammonium hydrogen fluoride aqueous solution alone. In order to stop the cleaning liquid on the wall surface as much as possible to improve the cleaning effect and to wrap the above-mentioned specific stain with the cleaning liquid to easily remove the stain, it is preferable to mix with a surfactant.

As the surfactant, various cationic surfactants, zwitterionic surfactants, nonionic surfactants, and anionic surfactants can be used. Examples of the cationic surfactant include a quaternary ammonium salt composed of benzalkonium chloride or the like, which is a surfactant whose dissociation in an aqueous solution and which exhibits surface activity becomes a cation. Examples of zwitterionic surfactants are long-chain alkyldi (aminoethyl) glycine or salts thereof, which are two types of surfactants that dissociate in aqueous solution and exhibit surface activity, such as anionic activity and cationic activity. And an aminocarboxylic acid or a salt thereof. Examples of nonionic surfactants include:
A surfactant that does not dissociate into ions in aqueous solution,
Examples thereof include ether type nonionic surfactants made of polyoxyethylene alkyl ether and the like. Examples of anionic surfactants include fatty acid salts and higher alcohol sulfate ester salts, which are surfactants that dissociate in an aqueous solution to form anions in the portion showing surface activity. The surfactant may be added in a small amount, for example, about 5 to 10% with respect to neutral ammonium hydrogen fluoride.

The above cleaning composition contains ammonia (water).
It is preferable to include an alkaline substance such as Even if dirt due to exhaust gas or the like can be removed by a cleaning composition composed of an alkaline substance and a surfactant, as described above, for cleaning the exterior material with strong composite dirt containing SiO ₂ , It is preferable to use a detergent composition composed of a mixture of neutral ammonium hydrogen fluoride, an alkaline substance and a surfactant. As shown in the following examples (comparative examples), the strong composite dirt containing carbon due to the exhaust gas and SiO ₂ due to the earth and sand is not on the acidic side but has a pH of 6 or more, preferably about 6 to 9 It has good alkalinity and can effectively remove the stain without damaging the base material such as mortar joints of the exterior material and the surface layer.

It is preferable to add a viscosity increasing agent (thickener) or a binder such as sodium alginate, sodium fibrin glycolate, and calanagen to the above detergent composition. It is preferable for preventing the cleaning liquid from easily dripping, stopping the cleaning liquid on the wall surface as much as possible, improving the cleaning effect, and wrapping the above-mentioned specific stain with the cleaning liquid to easily remove the stain.

If desired, various additives such as anti-soil redeposition agents composed of polymers such as perfume and polyvinyl alcohol, chelating agents and the like can be appropriately added to the above cleaning composition. Addition of hydrochloric acid or sulfuric acid is not preferred for this application.

[0011]

The present invention will be described below based on the following examples and comparative examples. Example 1 Neutral ammonium hydrogen fluoride (NH ₄ F) aqueous solution alone,
95% neutral ammonium hydrogen fluoride (NH ₄ F) aqueous solution
A mixture of 5% stearyl sulfate sodium salt as a surfactant, ammonium ammonium fluoride (NH ₄
The outer wall raster tile exposed to rainwater was subjected to glaze with an F.HF) aqueous solution alone and a hydrofluoric acid (HF) aqueous solution alone. That is, each cleaning agent was applied to the wall surface of the raster tile with a resin brush, allowed to stand for 30 seconds, washed with water, and then wiped and dried with a waste cloth. These cleaning solutions were evaluated by the appearance of the tiles after cleaning and the glossiness before and after cleaning. The results are shown in Table 1.

(1) Corrosion (Appearance): A metal scrubbing brush was applied to the washed raster tile, and the tile surface was lightly rubbed with the scrubbing brush to see the extent to which the metal trace remained black.
◯ indicates that the tile surface does not remain black and does not corrode, and is good, and X indicates that the tile surface remains black and corrodes the tile surface. (2) Glossiness (reflectance): Glossiness (%) of the wall surface of the raster tile before and after washing was measured. The glossiness is measured by a gloss checker model number IG310 manufactured by HORIBA,
Measure the glossiness of the raster tile wall surface before cleaning, apply each cleaning agent to the raster tile wall surface with a resin brush, leave it for 30 seconds, wash it with water, wipe it off with a waste cloth and dry it The degree was measured.

[0013]

[Table 1]

As is clear from the above results, as in Comparative Product D, in hydrofluoric acid (HF), when a metal scrubber was applied to the tile after washing to rub the tile surface, a metal trace remained black and the tile remained It shows that the surface is corroded. Also,
The decrease in glossiness after cleaning is significant, indicating that the gloss of the tile surface is reduced due to corrosion. Although hydrofluoric acid (HF) has excellent stain solubility, it generates gas. Also, like the comparative product C, even with acidic ammonium fluoride (NH ₄ F.HF), metal traces similarly remain black,
It shows that the tile surface is corroded, and that the gloss of the tile surface is reduced. On the other hand, like the products A and B of the present invention, neutral ammonium hydrogen fluoride (N
When H ₄ F) is used, it does not corrode the surface of the white outer wall tile that has been glazed, does not reduce the gloss of the tile surface, and is excellent in removing dirt adhering to the tile surface. Shows. Further, it is found that it is effective in the pH range of 6 or more.

Example 2 Neutral ammonium hydrogen fluoride (NH ₄ F) aqueous solution 85%
In the same manner as in Example 1, using a cleaning liquid containing 5% of sodium stearyl sulfate ester as a surfactant, 5% of ammonia water and 5% of sodium fibrin glycolate, the exterior wall surface of a highway was washed. As a result, it was possible to dissolve and remove the adhered stain without corroding the surface and reducing the gloss.

[0016]

As described above, according to the present invention, in the cleaning of the wall surface of the exterior material, the surface of which is provided with glaze (glazing) for the purpose of improving gloss, protecting the surface, or decorating, the base material of the exterior material is washed. As a result, it is possible to provide a cleaning technique that has a high cleaning effect without damaging the surface layer and that can effectively dissolve and remove specific defects.

Claims (4)

[Claims] 1. The chemical formula N is applied to the surface of the exterior material on which dirt is attached.
A method for cleaning the surface of an exterior material, which comprises applying a cleaning liquid containing neutral ammonium hydrogen fluoride represented by H ₄ F as an essential component to dissolve and remove stains adhering to the surface of the exterior material. 2. The method for cleaning the surface of an exterior material according to claim 1, wherein the cleaning liquid is composed of neutral ammonium hydrogen fluoride and a surfactant. 3. The exterior material is a wall tile and is a raster tile having a glaze on its surface.
Alternatively, 2 is a method of cleaning the surface of the exterior material. 4. A cleaning liquid for removing dirt adhering to the surface of an exterior material, wherein the cleaning liquid contains neutral ammonium hydrogen fluoride represented by the chemical formula NH ₄ F as an essential component. A cleaning solution for cleaning the exterior surface.