JPS62144905A - Mold release agent for concrete formwork - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Purpose of the Invention In recent years, materials such as stainless steel, aluminum, and synthetic resin have come to be increasingly used for concrete formwork. These materials are more expensive than the wood and steel that have been commonly used in the past, but concrete on a clean surface? It has the advantage of being able to be stamped and having a strong formwork that can withstand long-term use. However, conventional release agents (i.e., oil-based release agents based on mineral oil and vegetable oil with the addition of aliphatic amines, aliphatic amides, etc.) and mineral oil or their mixtures are used to form molds for such expensive materials. When using a water emulsion type emulsion made with a nonionic or anionic surfactant such as an ether or ester type, the following disadvantages occur and the concrete Z cannot be applied to the desired clean skin surface. It cannot be poured. That is, first, an oil film remains on the mold surface and prevents the adhesion of finishing agents such as mortar and paint. Third, the oil film left on the concrete surface discolors, causing oil stains.

Fourth, air bubbles occur on the concrete surface. Fifth, because the surface of the formwork used for pouring concrete into slabs is polished, it is slippery and it is extremely dangerous to work on reinforcement work because your feet may slip. Sixth, if the release agent does not stick partially due to the first reason, or becomes extremely thin, concrete slag will stick to it, and the conventional simple removal process of scraping off the slag will damage the formwork surface, resulting in expensive costs. Since the formwork will be ruined, special work will be required and it will be very troublesome. Seventh, there were drawbacks such as the finished concrete lacked luster and had a poor finish.

This invention takes into consideration the above-mentioned drawbacks, improves the releasability of concrete and formwork, and provides a special peeling method for stainless steel, aluminum, and synthetic resin formwork in order to obtain a clean concrete surface and a clean formwork surface. A new cationic compound stripping agent that is different from conventional stripping agents! It is completed.

(2) Structure of the Invention This invention uses a fatty acid polyamine polyamide compound as the main component, but it does not disperse (dissolve in colloidal form) in water and therefore does not act as a surfactant, but it does not work as a surfactant in acidic water. Performance as a surfactant when dispersed and ionized to become cations! It manifests itself. The te fatty acid polyamine polyamide compound exhibits the performance of a surfactant in an acidic aqueous solution of either an inorganic acid or an organic acid, but since an inorganic acid requires post-treatment, an organic acid is preferable. Among organic acids, formic acid, acetic acid, and oxalic acid are suitable because they are inexpensive, but since formic acid and oxalic acid are toxic, non-toxic acetic acid is most suitable.

Next, an example of the stripping agent of this invention will be explained. Polyamine polyamide compound 13% by weight acetic acid
0.7 wt% water
86.3% by weight.

In the above examples, the polyamine polyamide compound is obtained by the following manufacturing method.

Fatty acids are higher saturated fatty acids (general formula QnH2n+ IC
○○H) is suitable, and examples thereof include lauric acid, valmitic acid, stearic acid, and behelic acid, among which stearic acid, which is available at low cost, is most suitable.

Amine compounds include ethylenediamine, diethylenetriamine, triethylenetetramine, and tetraethylenepentamine, and all of these can be used as raw materials.

4 ethylenediamine per 74 mol (molecular weight) of fatty acid
mol or diethylenetriamine in a proportion of 2 mol,
0 fatty acid amide (R
-C! O.NH.OH2°OH, -NH) is produced at a ratio of 4 moles. Furthermore, urea (NH,) is added to this. co”g
When added at a ratio of i mole and heated at 20G-210℃ for 30 minutes, it reacts to form a fatty acid polyamine polyamide compound (
R@C! O@NH-OHLCH2) N / is produced in a proportion of 1 mole.

(3) Effects of the invention Polyamine polyamide compounds have superior adhesion to molds compared to conventional anionic compounds such as sodium salts, potassium salts, amine salts, or sodium sulfonate salts of fatty acids, and the coagulated film is strong. It also has water repellency and adheres well to molds made of stainless steel, aluminum, synthetic resin, etc., forming a film even when the water dilution rate increases. Moreover, the stripping agent of this invention dissolves easily by adding water, so that there is no need for stirring.

Therefore, application to the formwork can be easily done by freely selecting a sprayer, brush, or roller depending on the application location. Moreover, the inventive stripping agent exhibits the following effects that conventional stripping agents cannot achieve. 1. The finished concrete surface is smooth and beautiful, with no oil stains or air bubbles. 2. It blends well into the formwork and can be applied evenly. &After application, it dries quickly and forms a smooth dry film.

4. It is easy to work on slabs without slipping.

5. Easily dissolves in cold and hot water and does not separate at all after dissolving.

6. Concrete slag does not adhere to the formwork surface,
There is no need for scraping work such as scraping or sandblasting, and there is no damage to expensive formwork. 7. Surface finishing agents (paint, mortar, etc.) for concrete surfaces
The adhesive strength is not hindered at all.

As described above, the stripping agent according to the present invention achieves the original purpose of stripping with a number of ground-breaking effects, significantly extends the service life of formwork, and is particularly excellent in workability. It is something. It goes without saying that the effectiveness of the stripping agent of the present invention can be increased by adding a preservative and a coloring agent, if necessary.

Claims (1)

[Claims] fatty acid polyamine polyamide Compound 5-20% by weight Formic acid, acetic acid, oxalic acid optionally 0.1-3% by weight of selected organic acids Water 77.0-94.9% by weight A concrete formwork stripping agent consisting of the following composition: