JPS60154842A - Hydrogen peroxide composition for casting mold - Google Patents

Abstract

PURPOSE:To extend the pot life and surface stability of the titled compsn. by incorporating hydrogen peroxide and a stabilizer such as aliphat. satd. monocarboxyluic acid homolog, etc. into said compsn. as the peroxide of an acid curing cold box method. CONSTITUTION:An acid curing resin such as furan resin or the like and peroxide contg. 15-50wt% hydrogen peroxide and 5-60% stabilizer such as aliphat. satd. monocarboxylic acid homolog are kneaded with granular refractories such as silica sand or the like. The mixture is permitted to stand for specified time and thereafter sulfur dioxide is passed therethrough for one second and compressed air for about five seconds, then a casting mold is formed. The pot life is considerably extended and the surface stability of sand is improved as compared to the case in which only the hydrogen peroxide is used, according to the above- mentioned method. Aliphat. unsatd. monocarboxylic acid homolog, arom. carboxylic acid homolog, etc. are also usable as the stabilizer.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an oxidizing agent used when forming a mold by adding gaseous or aerosolized sulfur dioxide to a refractory aggregate mixture containing an acid-curable resin and an oxidizing agent. be.

More particularly, the present invention is directed to specific oxidant compositions for the curable molds used as oxidizing agents.

Traditionally, when manufacturing cores and main molds at foundries, mold manufacturing methods using organic self-hardening binders have been used for reducing industrial waste pollution, streamlining productivity, and other advantages, such as water glass, cement, etc. It has become widely used as an alternative to manufacturing methods that use inorganic binders. Only 1. There are also some 11L mold manufacturing methods that use organic self-hardening binders.

Since resin and curing agent are added to the large granular sand and kneaded, the pot life is short, and hardening progresses through a chemical reaction in a few minutes to several tens of minutes, and the kneaded sand does not lose its cohesive strength. be.

Furthermore, in order to manufacture a mold by molding the kneaded sand into a model, it usually takes several tens of minutes to several hours to stand.

Therefore, the pot life of the kneaded sand is limited, and the mold manufacturing time is long, making it unsuitable for organic self-hardening molds.

Conventionally, these applications include the cloning method, which involves heat curing of a fire-resistant aggregate coated with phenolic resin, and the hot box method, which uses furan-based resin, but in recent years, methods have been used to save energy and improve productivity. Therefore, a method called the cold box method, in which a mold is instantaneously produced by blowing gas or aerosol into a sand mold, is becoming common in these fields.

One of the cold box methods is a urethane-based cold box method in which an organic polyisocyanate and a polyol-type resin are used as a binder for the mold, and an aerosol of tertiary amine is injected to harden the mold. This method has drawbacks such as poor disintegration of casting sand during casting production, and the tendency for casting defects such as sand traps, scoops, pinholes, and soot defects to occur.

Instead, acid-curing resins such as furan-based resins, phenolic resins, and urea-based resins described in Japanese Patent No. 807.786° are cured by blowing gaseous or aerosolized sulfur dioxide into the presence of an oxidizing agent. let The so-called acid-curing cold box method has been rapidly attracting attention in recent years as a method for solving the drawbacks of the urethane-based cold box method.

The present invention relates to an improvement in the acid-curing cold box method. As the oxidizing agent for the acid-curing cold box method, ketone oxides, oxides, diacyl oxides, organic oxidants, hydro-oxidants, dialkyl hydroxides, etc. can essentially be used; In consideration of safety and mold properties, ketone groove oxides such as methyl ethyl ketone peroxide and hydropot oxides such as tertiary hydroperoxide are used in practice. However, stiff peroxides are expensive and there are concerns about the danger of fire, and further improvements in these points are desired.

Hydrogen peroxide solution is inexpensive and has little risk of exposure to fire, but this product has the disadvantage of poor curing properties.
Practically speaking, it is not used much.

In other words, when hydrogen peroxide is used as an oxidizing agent in the acid-curing cold box method, the pot life of the aggregate mixture made by kneading fire-resistant aggregate, acid-curing resin, and hydrogen peroxide increases as the hydrogen peroxide decomposes. As a result, molds that are short or molded by injecting sulfur dioxide may be sandy.
There is a drawback that surface stability decreases.

The present inventors have conducted intensive research to improve the drawbacks of hydrogen peroxide water as an oxidizing agent in the acid-curing cold box method, and to improve the drawbacks of shoulder-type peroxides. The inventors have discovered that the above-mentioned difficulties can be significantly improved by using an oxidizing agent composition containing hydrogen as a main component, and have arrived at the present invention.

That is, the present invention relates to a peroxide composition that is used when manufacturing a mold by kneading and molding a granular refractory, an acid-curable resin, and a peroxide composition, and adding gaseous or aerosol sulfur dioxide. hydrogen peroxide as a quick brewer, formic acid as a stabilizer,
Aliphatic saturated monocarboxylic acid analogs such as acetic acid and propionic acid or their acidic esters or acid salts; aliphatic saturated polycarboxylic acid analogs such as oxalic acid, malonic acid, and succinic acid (excluding those with hydroxyl groups) ), acidic esters or acid salts of methane, aliphatic unsaturated monocarboxylic acid analogues such as acrylic acid and crotonic acid, acidic esters or acidic salts of methacrylates, and aliphatic unsaturated polyhydric acids such as maleic acid and fumaric acid. Carboxylic acid analogues (excluding those with a hydroxyl group), acidic esters or acidic salts thereof, aromatic carboxylic acid analogues (excluding those with a hydroxyl group) such as benzoic acid, cinnamic acid, phthalic acid, naphthaleneacetic acid, etc. (excluding) acidic esters or acidic salts of fish,
Heterocyclic carboxylic acid analogs (excluding those with hydroxyl groups) such as picolinic acid and furocarboxylic acid, or their acid esters or acid salts, polyacrylic acid or its acid esters or acid salts, polymaleic acid or its acid salts Curing characterized by containing at least one of ester or acid salt, polyacrylic acid copolymer or its acid ester or acid salt, maleic anhydride copolymer or its acid ester or acid salt. The present invention relates to a hydrogen peroxide composition for use as a sex mold.

The hydrogen peroxide composition of the present invention includes hydrogen peroxide 15 to
50% (by weight, same below), preferably 20-40
%: A stabilizer containing 5 to 60%, preferably 15 to 50% is suitably used.

In the present invention, as granular refractories, refractory particles for casting using the acid-curing cold box method, such as silica sand, zircon sand, and chromite sand with a high silica content, can essentially be used without being restricted to these. do not have.

In addition, as the acid-curable resin, any resin that can be cured using an acid as a curing catalyst can be used, but in general, urea/formaldehyde resin, phenol/formaldehyde resin, formaldehyde resin,
Furan resins and melamine/formaldehyde resins may be used alone or in combinations or co-condensed compositions of two or more thereof.

Usually, 100 parts by weight of granular refractories are mixed with 0 parts of acid-curing resin.
．． The mold is manufactured using 5 to 3.0 parts by weight of the oxidizing agent and 0.1 to 1.0 parts by weight of the oxidizing agent, but the present invention is not limited thereto.

Examples will be described below to further explain the present invention in detail, but the scope of the present invention is not limited by the Examples.

Examples 1 to 1o and Comparative Example 1 15 parts by weight of furan resin and 5 parts by weight of the hydrogen peroxide composition shown in Table 1 were added to 1,000 parts by weight of Enshu water-washed silica sand. After mixing, the mixture was stirred for a certain period of time. Leave it alone, 50φX5Gm/
Fill the mH mold, add 7 sulfur dioxide for 1 second, and compressed air for 5 seconds.
The strength of the mold immediately after molding was measured by aerating the mixture for seconds, and the shelf life (pot life) of the mixture was investigated. The results are shown in Table 1.

Examples 11 to 16 and Comparative Example 2 After adding and kneading 15 parts by weight of furan resin and 5 parts by weight of the hydrogen peroxide composition shown in Table 21C to 1,000 parts by weight of Nikko silica sand, the mixture was left to stand for a certain period of time, and 50φX 50 m
The strength of the mold immediately after molding was measured by filling a mold of /mI (with sulfur dioxide for 1 second and compressed air for 5 seconds) to determine the shelf life (pot life) of the mixture. It is shown in Table 2.

Procedural amendment (voluntary) 1. Display of incident Patent Application No. 10536/1983 2. Name of the invention Hydrogen peroxide composition for molds 3. Person who makes corrections Relationship to the incident: Patent applicant Kao Quaker Co., Ltd. 4. Deputy manager Detailed description of the invention in the specification 6. Contents of correction

Claims (1)

[Scope of Claims] 1. Oxide silk when manufacturing a mold by kneading and molding granular #1 large particles, an acid-curing resin, and a peroxide composition, and adding gaseous or aerosol sulfur dioxide. The compound contains hydrogen oxide as a peroxide, an aliphatic saturated monocarboxylic acid analogue or its acidic ester as a stabilizer, or an aliphatic saturated polycarboxylic acid analogue (with a hydroxyl group). Acidic esters or acidic salts of certain substances, aliphatic unsaturated monocarboxylic acid analogues, acidic esters or acidic salts of certain substances, aliphatic unsaturated polycarboxylic acid analogues (those with hydroxyl groups) Acidic esters or acid salts of aromatic carboxylic acids (excluding those with a hydroxyl group), acidic esters or acid salts of aromatic carboxylic acids (excluding those with a hydroxyl group), heterocyclic carboxylic acid analogues (excluding those with a hydroxyl group) Acidic esters or acid salts of polyacrylic acid or methane, acidic esters or acid salts of polymaleic acid or methacrylates, polyacrylic acid co-heavy metals or acidic esters thereof A curable mold groove hydrogen oxide composition, characterized in that it contains at least one of an acid salt, a maleic anhydride copolymer, an acid ester thereof, or an acid salt. 2- Composition according to claim 1, containing 15-50% by weight of hydrogen peroxide and 5-60% by weight of stabilizer. 3. The composition according to claim 2, containing 20 to 40% by weight of hydrogen peroxide and 15 to 50% by weight of a stabilizer.