JP3175865B2 - Release agent for die casting - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold release agent which is applied to the surface of a mold cavity during die casting to improve mold release of a cast product.

[0002]

2. Description of the Related Art At present, a water-soluble release agent is frequently used as a die-casting release agent. However, the water-soluble release agent is liable to cause run-out failure due to so-called water residue, and the water quality after use. There were inconveniences such as the need for wastewater treatment to prevent pollution.

[0003] In order to solve the problem of the water-soluble release agent, a release agent for die-casting in the form of powder has been proposed as disclosed in, for example, JP-A-3-243242. However, when this powdery release agent is used, the cost of equipment and facilities for applying the release agent to the mold cavity surface is increased, it takes time to apply the powdery release agent, There were problems such as polluting the environment, the release agent being easily deposited on the parting line surface of the mold and requiring a special mold.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of such a conventional problem, and there is a fear that a run-out defect caused by remaining water as in a conventional water-soluble release agent may occur. Release agent for die casting that does not require special equipment or molds unlike powdery release agents, and does not pollute the environment or accumulate on the parting line surface of the mold with use. Is to be provided.

[0005]

Die casting mold release agent according to claim 1 of the present invention that such a purpose achieved Means for Solving the Problems], the water-soluble Bas
Wet powder with silicone fine powder dispersed in an inder
The silicone fine powder has a spherical shape and a particle diameter of 0.1.
The silicone fine powder is prepared in the range of 3 to 20 μm.
Characterized by comprising 20-95% of total solids
It is. Further, the mold release agent for die casting according to claim 2 of the present invention comprises silicone fine powder as a main component of solid content,
It is characterized by using tetrahydroxyvaleric acid as a binder.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The most characteristic feature of the mold release agent for die casting according to the present invention is that it has a wet powder form. As a main component of the solid content, a silicone fine powder having excellent lubricity, a small specific gravity and a small cohesion than inorganic fine powder, and excellent heat resistance as compared with organic fine powder is used.

The silicone fine powder to be used is preferably spherical and has a uniform particle diameter in the range of 0.3 to 20 μm. Moreover, as a ratio to be used, 20 to
If it is less than 20%, the releasability and detergency will be poor, and if it is more than 95%, the adhesion to the mold cavity surface will be poor.

[0008] Then, an appropriate amount in the silicone fine powder (5
(~ 80%) filler. The type of filler used is not particularly limited, and examples thereof include graphite, talc, boron, and mixtures thereof.

[0009] D-TetrahydroxyValeric Acid is used as a binder. Specifically, 0.25 of D-tetrahydroxyvaleric acid
〜5% aqueous solution is used. When the content is 0.25% or less, the silicone fine powder hardly adheres to the mold, and when the content is 5% or more, gas is likely to be generated and scum may remain on the mold cavity surface.

[0010] When the die-casting release agent is applied to the surface of the mold cavity, a spray device similar to that of the conventional water-soluble release agent can be used.

Next, a die casting test was carried out using the release agent for die casting obtained as described above, a conventional water-soluble release agent and a powder release agent, and the results are shown in Table 1 below. Items were compared.

[0012]

[Table 1]

[0013]

As described above, the powder release agent for die casting according to the present invention is in the form of a wet powder in which silicone fine powder is dispersed in a water-soluble binder. As described above, it is not necessary to perform the special air blow after the application to the mold cavity surface, and there is no possibility that the run-out failure due to the residual water may occur.

In addition, between the surface of the mold cavity coated with the release agent and the cast product, the silicone, which is the main component of the release agent, is used.
It means that only the particle size of over emission fine powder is surely separated, also played the release agent serves as thermal insulation material, therefore, as it is clear from the test results in Table 1 above, molten metal temperature Even if casting is performed at a slightly low or low speed, a sound product can be cast without causing poor running of the melt.

Further, the powder release agent for die casting according to the present invention does not require a special device or mold as used in the case of the powder release agent at the time of use, and also has a risk of polluting the on-site environment. In addition, since air blow after application to the mold cavity surface as in the case of the conventional water-soluble release agent is not required, air pressure sufficient to atomize the release agent during spray application is sufficient. In conjunction with this, it is possible to greatly reduce the generation of noise due to coating or air blowing.

Further, as is clear from the test results shown in Table 1 above, the powder release agent for die casting according to the present invention has excellent adhesion to the mold surface, so that it is evenly distributed on the mold cavity surface. It can be easily applied to a suitable thickness and has excellent cleaning properties on the mold surface.Therefore, there is no danger that it will accumulate on the parting line surface of the mold with use.
Productivity can be improved.

Claims (2)

(57) [Claims] Claims: 1. A water-soluble binder and a silicone fine powder.
In the form of a wet powder in which the silicone fine powder is dispersed.
Are spherical and have a uniform particle size in the range of 0.3 to 20μ.
Containing 20 to 95% of the total solid content of the silicone fine powder.
A mold release agent for die casting, characterized by comprising: 2. A mold release agent for die casting, comprising silicone fine powder as a main component of solid content and D-tetrahydroxyvaleric acid as a binder.