JPS6186044A - Release agent for casting mold - Google Patents

Abstract

PURPOSE:To prevent the staining of a pattern owing to the sticking of a resin and sand in the stage of mixing an org. binder with a refractory granular material and producing a curable casting mold by using a release agent contg. the compd. expressed by the general formula and water or specific org. solvent. CONSTITUTION:The release agent contains 1 or >=2 kinds of the compd. expressed by the general formula, water or the org. solvent selected from the group consisting of aliphat. hydrocarbon of <=12C, arom, hydrocarbon, alicyclic hydrocarbon, halogented hydrocarbon, ether, acetal, ketone and ester or diluent selected from a freon solvent. In the formula, R denotes satd. or unsatd. aliphat. hydrocarbon of 7-30C, hydroxy aliphat. hydrocarbon, arom. hydrocarbon or alicyclic hydrocarbon, Y denotes the metals of the I, II, III or IV group metals of periodic table and n denotes the atomic valency of the metal. The compounding ratio of the respective component of the released agent is made to 0.1-50wt.% the above-mentioned compd. and 99.9-50wt.% diluent.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a mold release agent for molds, and particularly to a mold release agent used when manufacturing molds using an organic binder such as an acid-curable resin. This invention relates to a mold release agent that improves mold stains on uncured resins and sanded pipes.

[Conventional technology] Conventionally, in order to manufacture medium-sized molds, the shell molding method was used, in which a refractory granular material was coated with phenolic resin, and this was filled into a mold using air, pressure, etc., and thermoset molded. has been used.

However, in order to save energy during mold manufacturing, mold production speed, and improve the quality of molds and castings, the Co-) Lt Dovosox mold manufacturing method, which uses gaseous or aerosol materials to cure at room temperature, has been developed to replace the shell molding method. Serious attempts have been made to introduce it as a manufacturing method in the foundry industry.

The cold box method involves curing acid-curing resins, typically furan-based resins, with sulfur dioxide using peroxide as an oxidizing agent, and curing polyols and polyisocyanates using an aerosol-like tertiary amine as a catalyst. There is a urethane cold box that hardens.

Molds using urethane cold boxes have drawbacks such as poor disintegration of casting sand during casting production, and the tendency to cause casting defects such as sand trapping, scooping, pinholes, and soot defects.

On the other hand, the Francold box has been rapidly attracting attention in recent years as a method for solving the above-mentioned difficulties.

The present invention relates to a mold release agent suitable for use in the Fran cold box method, and is used to improve mold stains, which are a factor that causes a decrease in productivity in cold boxes that harden instantly by gas injection at room temperature. The present invention relates to a mold release agent.

Conventionally, automatic molding machines have been used to manufacture molds in medium to large quantities, in which acid-curing resin and peroxide are added and kneaded to fire-resistant granular material to coat the surface of the fire-resistant granular material, and then molded using air pressure, etc. Filling, molding, curing, and removal are automatically performed continuously in a cycle of less than one minute.

[Problems to be Solved by the Invention] However, in the cold box method, the resin/peroxide coated on the surface of the refractory granular material may not be present on the model surface due to the pressure of the curing gas and air and uneven gas flow. It has the disadvantage that it tends to cause model stains such as resin adhesion caused by migration and sand adhesion due to uneven hardening of the mold surface.

Due to the adhesion of model dirt to resin and sand, the molding machine needs to be stopped several times during continuous production to remove model dirt, reducing mold productivity.

Therefore, in order to further improve mold productivity in the cold box method, there is a need for a mold release agent that improves resin adhesion and sand buildup.

Means for Solving Problem E] The present inventors have discovered a mold release agent that can significantly improve model staining and further improve mold productivity (as a result of intensive research, the present invention has been achieved). .

That is, the present invention adds an organic binder to a refractory granular material,
A mold release agent that prevents staining of a model and is used when manufacturing a curable mold by kneading, and is a mold release agent that is made of one or more compounds represented by the following general formula (1), and water or carbon. number 12
Contains a diluent selected from the following organic solvents selected from the group consisting of aliphatic hydrocarbons, aromatic hydrocarbons, alicyclic hydrocarbons, halogenated hydrocarbons, ethers, acetals, ketones, and esters, or freon-based solvents. The present invention relates to a mold release agent for molds, which is characterized by:

(R-COOh-Y ・-・-(1) (wherein, R
is a saturated or unsaturated aliphatic hydrocarbon, hydroxy aliphatic hydrocarbon, aromatic hydrocarbon or alicyclic hydrocarbon having 7 to 30 carbon atoms, Y is a saturated or unsaturated aliphatic hydrocarbon having 7 to 30 carbon atoms, and Y is a saturated or unsaturated aliphatic hydrocarbon having 7 to 30 carbon atoms; U,
The compound represented by the above general formula (1) used in the present invention is a saturated or unsaturated aliphatic hydrocarbon carboxyl compound, a hydroxy/aliphatic carbonized It is an organometallic soap consisting of a hydrogen carboxyl compound, an aromatic hydrocarbon carboxyl compound, or an alicyclic hydrocarbon carboxyl compound, and a metal of Group 1, ■, ■, or ■ of the Periodic Table of the Elements, and is a saturated or unsaturated aliphatic carbonized soap. Hydrogen carboxyl compounds and hydroxyaliphatic hydrocarbon carboxyl compounds include caproic acid, capric acid, lauric acid, myristic acid, valmitic acid, stearic acid, behenic acid, montanic acid, oleic acid, which are derivatives from natural animal and vegetable oils. linoleic acid,
Carboxyl compounds such as 2-ethylhexoic acid, which is a fatty acid such as lyrinic acid, stearolic acid, castor oil fatty acid, and soybean oil fatty acid, and mineral oil fatty acid are mentioned, and aromatic and alicyclic hydrocarbon carboxyl compounds include 1 , benzoic acid, naphthalic acid, and naphthenic acid.

Further, as metals constituting the organic metal soap, metals of Group 1, ■, ■, or ■ of the periodic table, such as lithium, sodium, potassium, magnesium, calcium, zinc, aluminum, titanium, zircon, and tin, are used. .

The diluent used in the present invention is water or carbon number 12
Selected from the following organic solvents or Freon solvents selected from the group consisting of aliphatic hydrocarbons, aromatic hydrocarbons, alicyclic hydrocarbons, halogenated hydrocarbons, ethers, acetals, ketones, and esters, and as a Freon solvent. Examples include trichlorotrifluoroethane.

The blending ratio of each component of the mold release agent of the present invention is expressed by the general formula (1)
0.1 to 50% by weight of the compound represented by, 99.9% diluent
~50% by weight is preferred.

Regarding the form in which the mold release agent of the present invention is used, it is easier to handle when used in the form of a solution in which the compound represented by general formula (1) is dispersed, emulsified, or solubilized in water and an organic solvent such as acetone or xylene. , preferred from the viewpoint of work environment, etc.

The release agent may be applied to the model using a spray, a brush, or the like. The processing may be carried out every time or periodically. That is, the same method as used for known mold release agents may be used, and the present invention is not limited thereto.

The mold manufacturing process used to prevent mold staining in the mold release agent of the present invention includes an incuring method other than the Franco cold box method and a method using an organic self-hardening binder. It is not limited.

〔Effect of the invention〕

With the mold release agent of the present invention, compared to the case of using conventionally known commercially available silicone, fluorine, mineral oil, fat wax type mold release agents,
The number of continuous mold operations (commonly referred to as the number of shots) before mold contamination such as resin adhesion and sand buildup occurs can be increased by an average of 10 times or more.

[Effect]

Assuming the above reason, by using the compound represented by the above general formula (1) (organometallic soap), a uniform and clear separation membrane is generated between the mold surface and the model surface,
Separation force that prevents resin from adhering to the model and sand from sticking to the model.
In addition to lowering the physical and chemical interface cohesive energy between the model surface and the mold surface, it also lowers the physical and chemical cohesive energy on the model surface, and the mold side is treated with organic metal soap, which is used in the Francold box method. This is thought to be due to the fact that by slightly increasing the rate of the oxygen-releasing decomposition reaction of peroxide, the production of the acid catalyst becomes slightly faster, which slightly increases the cohesive energy on the mold surface.

In addition, the organometallic soap of the present invention exhibits cleaning efficiency as a surfactant, making it easier to remove resin adhesion remaining on the model and model dirt with sand coated on the surface of the model, and reducing reattachment energy. It is thought that this is because of this.

[Examples] Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to the following Examples.

Example Disc rotor cores (core weight: 1.5 kg x 2 pieces, outer diameter 300 mm) were made using an IC-750 horizontally split automatic molding machine (manufactured by Naniwa Seisakusho) using the Fran cold box method.
A continuous molding test was conducted using a mold (φ, fin part mold thickness: 7 mm) to measure the number of consecutive shots until resin deposits and sand deposits were generated on the disk rotor core mold surface.

The measurement results are shown in comparison with commercially available silicone, fluorine, mineral oil, and oil/fat x-based mold release agents without using the mold release agent of the present invention.

In addition, the method and amount of application of the mold release agent is 2 mg/cI112 with a marsupial of mold release agent liquid every 2 shots using an automatic spray device.
I applied it and compared it.

In order to keep the mold surface condition constant before starting the test, the mold surface after the test was polished by sandblasting, and the surface was cleaned with an acetone/xylene mixed solvent and then dried.

The concentration of the release agent component was adjusted by diluting Marsupial with water and organic solvents such as acetone and xylene that can be solubilized and microdispersed. The results are shown in Table 1.

The mold composition and mold curing conditions, which are the continuous molding test conditions in this example, are as follows.

<Mold composition> Silica sand (domestic Hamaoka water-washed silica sand) 1000 parts by weight Resin (kaolite toner KX-205) 15 Peroxide (
Kaolite toner P-71) 6 molding curing conditions> Old pressure crab 3. Okg/cm"Blo positive opening time, 0se (SOt pressure crab 2.0kg7cm"gas
Sing time: 1.0secpurgeAIR pressure crab 3
．． Okg/cm” purge time: 5.Osecpu
rgeAIR temperature: 180°C 1 cycle time: 3
5 sec As shown in Table 1, compared to various reprint mold release agents, the mold release agent of the present invention improves the number of consecutive shots where resin deposits and sand deposits occur, and the rate of improvement is at least 3 times,
At the highest level, it was observed to be more than 10 times more visible, indicating a sufficient effect in preventing model stains caused by resin deposits and sand deposits.

Claims (1)

[Scope of Claims] 1. A mold release agent for preventing staining of a model, which is used when manufacturing a curable mold by adding and kneading an organic binder to a refractory granular material, which includes the following general One or more compounds represented by formula (1) and water or an aliphatic hydrocarbon having 12 or less carbon atoms, an aromatic hydrocarbon, an alicyclic hydrocarbon, a halogenated hydrocarbon, an ether, an acetal, or a ketone. and a diluent selected from an organic solvent selected from the group consisting of esters and esters or a freon-based solvent. (R-COO)-_nY...(1) (wherein, R is a saturated or unsaturated aliphatic hydrocarbon, hydroxyaliphatic hydrocarbon, aromatic hydrocarbon, or alicyclic hydrocarbon having 7 to 30 carbon atoms) , Y is element I of the periodic table,
Group II, III or IV metal, n indicates the valence of the metal) 2. 0.1 to 50% by weight of the compound represented by the general formula (1)
The mold release agent according to claim 1, which contains 99.9 to 50% by weight of a diluent.