JPS6032565B2 - Mold release agent for lightweight cellular concrete manufacturing molds - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mold release agent for molds for producing lightweight cellular concrete.

Lightweight cellular concrete is lighter and has lower thermal conductivity than ordinary concrete, so it is widely used as a heat insulating and soundproofing material, and when reinforced with reinforcing steel, as a structural material.

This lightweight cellular concrete is made by mixing a mixture of cement, lime, and silicic acid powder with a small amount of foaming agent such as aluminum powder, and adding water to form a slurry, which is foam-molded in a mold. After that, it is manufactured by autoclaving. Lightweight aerated concrete requires a good surface finish, so
In its production, a wooden mold is insufficient as a formwork, so a metal mold is used, and in foam molding, it is necessary to increase the precision of the product, protect the mold, and make the molding process smoother. To do this, a release agent is often applied to the mold using a brush, spray, etc.

Conventionally, tin oil, fats and oils, waxes, fatty acids, soaps, metal powders, polymers, or mixtures thereof are known as mold release agents for concrete production.

However, since the production of lightweight aerated concrete requires special operating conditions that involve foaming during molding, there are few mold release agents for general concrete production that exhibit satisfactory performance. Furthermore, mold release agents for wooden molds do not always exhibit sufficient performance when used in molds. In addition, conventional mold release agents for lightweight cellular concrete manufacturing molds tend to drip after being applied to the mold due to a decrease in viscosity in the summer, or cause clogging during spray application due to an increase in viscosity in the winter, or cause additives to It had problems such as separation and sedimentation. Japanese Patent Publication No. 47-48772 discloses a mold release agent for wooden molds comprising refined mineral oil-based tium soap or a mixture thereof with a surfactant.

Examples of the surfactant include polyoxyethylene alkyl phenol ether and other nonionic and anionic surfactants. However, although a mold release agent made of refined mineral oil and lithium soap has sufficient performance as a mold release agent for general wooden molds used in concrete production,
When used for the purpose of the present invention, the finished surface of the product concrete may not be smooth and the mold may be damaged. Moreover, even if this type of surfactant is further added, its performance is still insufficient. Tokuko Sho 49-10090 is
Mineral oils, animal or vegetable oils (e.g. paraffin, vaseline, lard, or rosin) which are semi-liquid, muddy or solid at room temperature, and mineral oils which are fluid at room temperature (
For example, a mold release agent for concrete production wood molds is disclosed, which comprises kerosene, heavy oil, spindle oil, machine oil or machine oil).

However, although the template agent disclosed in the publication shows sufficient performance as a mold release agent for wooden molds for concrete production, when used for the purpose of the present invention, it has poor adhesion to molds. , the acid type agent may drip after application. Special Public Service 1977
No. 18768 discloses a concrete mold release agent containing a blend of mineral oil and fatty acid distilled pitch.

Here, examples of fatty acids include botanical oil, soybean oil, linseed oil, and rapeseed oil, and it has been revealed that the same molding agent is particularly effective for molds made of steel. However, the mold release agent disclosed in this publication does not exhibit sufficient performance for the purpose of the present invention, and is not preferred because it colors the concrete product. Tokukan Sho 49-176919 discloses a template agent for concrete molds for producing concrete in which a mixture of mineral oil, grease, oil, fat, plastic, polymer, etc. is dissolved with heat or a solvent. However, this template agent is used for special purposes and is insufficient for the purpose of the present invention. Furthermore, the same invention does not specifically disclose the composition of the present invention. An object of the present invention is to provide a template agent for molds for producing lightweight cellular concrete that solves the drawbacks of these conventional mold release agents.

The present invention comprises 'a} petroleum lubricating oil fraction, 'b' vegetable oil and/or 'c-0.01-1% by weight of C,2-C,8 fatty acids, and 'd- lithium soap grease. A mold release agent for lightweight cellular concrete manufacturing molds, comprising 0.01 to 15% by weight.

Regarding. In the present invention, 'a} petroleum-based lubricating oil component is,
30 using a food cup according to JIS K5402
The flow time at q0 is 20-11M sand, preferably 3
Indicates 0-8M sand.

Among these petroleum-based lubricating oil fractions, naphthenic ones are particularly preferred. {b' Vegetable oil and fat as used in the present invention is at least one type of oil and fat selected from the group consisting of soybean oil, olive oil, rapeseed oil, and palm oil.

Among these, soybean oil and olive oil are preferred, with large oil being the most preferred. 'c-C,2 in the present invention
~C,8 fatty acids include C,2 lauric acid, C,4 myristic acid, C,6 palmitic acid, and C,8 olefinic acid.
At least one compound selected from the group consisting of: If the number of carbon atoms in the fatty acid is less than this range, the corrosion resistance of the mold release agent may decrease and rust may occur on the mold. On the other hand, if the number of carbon atoms in the fatty acids exceeds this range, these fatty acids may solidify at low temperatures. Among these fatty acids, those with C,4 to C,6 are preferred;
, 6 to C, 8 are more preferred. The most preferred fatty acid is oleic acid. In the present invention, [b] vegetable oil and/or [clC, 2 to C, 8 fatty acids are essential components for maintaining a good finished surface of product concrete and for performing mold release work smoothly. vegetable oil and'
c}A mold release agent containing both C,2-C,8 fatty acids has more preferable performance.

The amount of 'b-vegetable oil and/or 'c}C,2 to C,8 fatty acids is 0.01 to 1% by weight based on the entire surfactant,
In particular, it is preferably 0.1 to 5% by weight.

When both are used together, 0.01 to 1% by weight each,
In particular, it is preferably 0.1 to 7% by weight. If the amount added is less than this range, the effect of the addition will not be sufficient, and if the amount added exceeds this range, there will be no commensurate effect, which is rather unfavorable from an economic standpoint. In the present invention, 'd) Richiyu soap grease means C,2
~C,8 fatty acids are saponified with lithium hydroxide, etc. Lithium soap obtained by dispersing it in a liquid lubricant as a thickening agent, for example, is commercially available under the trade name of Nippon Oil Co., Ltd.'s Epinoc 2. ing.

This lithium soap grease is an essential component for imparting adhesion to the mold to the mold release agent, and its amount is 0.01 to 15% by weight, particularly 0.1 to 15% by weight based on the entire mold agent.
Preferably it is 7% by weight. If the amount added is less than this range, the effect of the addition will not be sufficient, and even if the amount added exceeds this range, there will be no commensurate effect, which is rather unfavorable from an economic point of view. Other known metal soap greases include sodium, calcium, and barium soap greases, but all of these are unfavorable from the standpoint of storage stability because they separate and settle at low temperatures or when heated.

Hereinafter, the present invention will be explained in more detail with reference to an example of rice cake.

Examples and Comparative Examples Various mold release agents as shown in the table were manufactured and used in the manufacture of lightweight cellular concrete.

The working conditions and performance evaluation criteria are as follows. Working conditions A mixture consisting of 1 part cement, 2 parts lime and 7 parts silica sand,
A small amount of aluminum powder was added as a foaming agent, and water was added to form a slurry, which was poured into a mold coated with the mold release agent.

After foaming in a powder bowl (approx. The mold was removed from the product concrete, and the template agent was applied again, and the mold was used repeatedly.
Performance evaluation criteria Mold release agent: Evaluated based on mold release properties when removing the mold from finished concrete.

Product finish: The surface smoothness, color, etc. of the product concrete after the template were observed with the naked eye, and the reproducibility of the product finish was evaluated.

Adhesion to the mold: Evaluation was made based on the degree of sagging immediately after spraying the mold release agent and after leaving it for a day and night.

Storage stability: The presence or absence of sediment in the release agent was observed at low temperatures and during heating.

Condition of mold: Evaluation was made based on the condition of the surface of the mold after repeated mold work and the presence or absence of damage.

All test results were evaluated on a scale of 5 (excellent) to 1 (poor).

Example 1 is a naphthenic mineral oil (Food Cup Test 59
This is a template agent consisting of soybean oil, oleic acid, and lithium soap grease, which is excellent in all properties, and is the most preferred composition in the present invention.

Examples 2 and 3 contain vegetable oil or C,2 fat, respectively, along with naphthenic mineral oil and lithium soap grease.
It is a mold release agent containing ~C,8 fatty acids, and exhibited performance second only to Example 1.

Comparative Example 1 is a mold release agent made of naphthenic mineral oil and lithium soap grease.

Although it has excellent adhesion to molds, since it does not contain vegetable oil or C,2-C,8 fatty acids, it is insufficient in various properties including mold release agent. Comparative Example 2 is a mold release agent obtained by adding polyoxyethylene alkyl phenyl ether as a surfactant to the composition of Comparative Example 1.

Claims (1)

[Claims] 1 (a) petroleum lubricating oil fraction, (b) vegetable oil and/or (c) C_1_2 to C
0.01 to 10% by weight of _1_8 fatty acids, and (d)
A mold release agent for molds for producing lightweight cellular concrete consisting of 0.01 to 15% by weight of lithium soap grease. 2. (b) The release mold for lightweight cellular concrete production molds according to claim 1, wherein the vegetable oil is at least one oil selected from the group consisting of soybean oil, olive oil, rapeseed oil, and palm oil. agent. 3 (c) The lightweight cellular concrete production mold according to claim 1, wherein the C_1_2 to C_1_8 fatty acids are at least one compound selected from the group consisting of lauric acid, myristic acid, palmitic acid, and oleic acid. Release agent.