JPS63220944A - Water base parting agent for die casting - Google Patents

Abstract

PURPOSE:To obtain water based parting agent having excellent parting property, to prevent sticking of deposit on die parting plane and to obtain a product having good dimensional accuracy by containing polyoxyalkylene glycolbisphenol A ether shown in the formula as the water base parting agent for the die casting. CONSTITUTION:At the time of casting the die casting product of Al or Zn, etc., the polyoxyalkylene glycolbisphenol A ether obtd. by reacting ethylene oxide or propylene oxide to bisphenol A and shown by the formula is contained in the parting agent. In the formula, R1 and R2 are ethylene-radical or propylene- radical, and both may be either the same or different radicals respectively, and (m) and (n) are the positive integral numbers. In this way, the water based parting agent having excellent parting property is obtd. and the deposit on the die parting plane is not stuck and the die casting product having good dimensional accuracy is obtd.

Description

[Detailed description of the invention] Industrial applications The present invention relates to an aqueous jlffi agent for die casting.

Conventional A-type mold release agents for die casting are broadly classified into oil-based glffi agents and water-based mold release agents, but oil-based mold release agents pose problems in the work environment due to the risk of ignition and smoke generation, so recently water-based mold release agents have been used. agents are frequently used. The aqueous mold release agent used has a composition in which mineral oil, fat, wax, silicone oil, etc. are emulsified or dispersed in water using a surfactant. Water-based aX agents generally have poor adhesion to high-temperature molds compared to oil-based S-type agents, so they often have inferior mold release properties. A water-based mold release agent containing a large amount of wax (halafine wax, polyethylene wax, oxidized paraffin wax, etc.) has been used.

However, when Type Ia agent containing wax is used, substances generated due to thermal changes in the GL agent composition during use adhere to the mating surfaces of the mold and deposit, which causes the dimensions of the product to deteriorate. There were problems such as deterioration of accuracy.

Problems to be Solved by the Invention Due to the above-mentioned current situation, water-based I@ which has excellent mold releasability, does not allow deposits to adhere to the mold mating surfaces, and allows die-cast products with good dimensional accuracy to be obtained. It is an object of the present invention to provide a molding agent.

Means for Solving the Problems In order to solve the above problems, the present inventors conducted intensive research and found that the GL type properties of the aqueous TLFFI agent were improved by incorporating polyoxyalkylene glycol bisphenol A ether. Furthermore, they discovered that deposits do not adhere to the mold mating surfaces, and completed the present invention.

That is, the present invention provides a polyoxyalkylene glycol bisphenol A ether represented by the following general formula (wherein R1 and R2 in the formula 2 are an ethylene group or a propylene group, and 1 and 2 may be the same or different, (m and n are positive integers.) This is an aqueous mold release agent for die casting.

In the above general formula, there is no limit to the ratio of m and n,
The average molecular weight of the compound represented by the general formula is 400 to 2
．． 000 is appropriate.

The polyoxyalkylene glycol bisphenol A ether represented by the above general formula can be produced by a known method of reacting bisphenol A with ethylene oxide and/or propylene oxide.

The aqueous mold release agent of the present invention can be obtained by containing the above compound in water.

In addition to the essential ingredients, the giz agent of the present invention contains mineral oil, animal and vegetable oils, fatty acid esters, and
Synthetic lubricating oil, silicone oil, surfactant, etc. may be used in combination, but it is not preferable to use waxes in combination from the viewpoint of preventing deposits from adhering.

The aqueous mold release agent of the present invention can be used as a GL type agent for aluminum or zinc die casting.

EXAMPLES Next, the present invention will be specifically explained with reference to Examples and Comparative Examples. However, the present invention is not limited in any way by these Examples and Comparative Examples.

Example 1 Polyoxyalkylene glycol bisphenol A ether (oxyalkylene is oxyethylene and oxypropylene, the average number of moles added of the former is 2 moles, the average number of moles added of the latter is also 2 moles,
The average molecular weight of the compound is 400) 9 g, mineral oil (40
5 g of castor oil, 6 g of 6 moles of ethylene oxide adduct of nonylphenol,
5 g of oleic acid and 1.6 g of morpholine were added and stirred for 30 minutes using a stirrer. The mixture thus obtained was gradually added to 68.4 g of water while stirring to obtain an aqueous mold release agent of the present invention.

Example 2 In the same manner as in Example 1, an aqueous mold release agent (type a agent of the present invention) having the following composition was obtained.

Polyoxyalkylene glycol bisphenol A ether (oxyalkylene is oxyethylene and oxypropylene, the average number of moles added for the former is 7 moles, the average number of moles added for the latter is also 7 moles, and the average molecular weight of the compound is 900. be)
12g mineral oil (kinematic viscosity 480 mrn' at 40°C)
/S) 6g castor oil
3g nonylphenol adduct with 6 moles of ethylene oxide 6g oleic acid 3g morpholine
1g water
69g comparative example! Mineral oil (kinematic viscosity 480 mbar/s at 40°C) 5g oxidized polyethylene wax (melting point 110°C, acid value 15) 9g castor oil 5g nonylphenol ethylene oxide 6 mole adduct
6g
Oleic acid 5g Morpholine 1.6g Water
68
, 4g Comparative Example 2 Silicone oil emulsion (solid content 60%) (@KM870 manufactured by Etsu Silicone Co., Ltd.) 3g mineral oil (40°C) eJ
Viscosity 480mm'/S) 6g oxidized polyethylene wax (melting point 110°C, acid value 15) 9g castor oil 3g nonylphenol ethylene oxide 6 mole adduct
6g oleic acid 3g morpholine 1g water
6
9g Test Example An aqueous solution diluted by adding 99 times the weight of water to the mold release agent of the Example and Comparative Example was used to perform die casting of aluminum. We investigated the number of shots, the finished product surface, and the product defect rate due to poor dimensional accuracy. The results are shown in Table 1.

Table 1 Note that in the case of Examples, no deposits were observed on the mold mating surfaces, whereas in Comparative Example 1, deposits were significantly attached.

Effects of the invention The aqueous mold release agent for die casting of the present invention has excellent mold release properties,
Moreover, since deposits do not adhere to the mold mating surfaces, by applying this to die casting, productivity can be increased, and die-cast products with beautiful finished surfaces and good dimensional accuracy can be efficiently manufactured.

Claims (1)

[Claims] Polyoxyalkylene glycol bisphenol A ether represented by the following general formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (However, R_1 and R_2 in the formula are ethylene groups or propylene groups, and both may be the same or different, and m and n are positive integers.