CN87104522A - The chemical roughing treatmenting solution of wax - Google Patents

Abstract

The chemical roughen that the present invention describes is handled, and uses a kind of solution of special formulation, and this solution is by K ₂Cr ₂O ₇, CrO ₃, H ₂SO ₄Form, the roughening treatment time is 30-300 seconds, again through sensitization, activation, can carry out chemical plating.This solution also can be used for containing the compound wax-pattern of wax and some metal, glass or pottery formation, carries out chemical roughen and handles.Handle wax-pattern with the chemical roughing solution that the present invention describes, the conductive metal film that obtains has stronger sticking power, pastes die face and keeps former wax-pattern surface details without distortion, and its color is the true qualities of this metal.Wax-pattern through surface metalation can the various metal productss of electroforming.

Description

The present invention relates to a kind of chemical treatment technology of wax-pattern surface metalation, the chemical roughing treatmenting solution when before electroforming, making the wax-pattern surface metalation with chemical process.

Electroforming process is exactly after core surface electrolytic deposition layer of metal, it is separated with core rod and obtains the processing method of metal products.

Many solid matters all can be used as the material of electroforming core rod, as core rod many advantages are arranged with wax, and for example it is convenient to processing, are easy to fusing, and cost is low; Wax also can be used as combined electrical mold core binder or inlay; For example, can give the part of metal or nonmetallic plate, bar or other shape being placed on earlier in the wax-pattern core, when the part surface of this class part is exposed on the surface of wax-pattern core, after the electroforming they just and the electroforming metal layer link into an integrated entity; To the built-up type core rod, can there be the fit-up gap in its junction, embedding can be filled out with wax in these gaps.Non-conductive because of wax, before electroforming, must use appropriate means coated one deck conductive coating, i.e. surface metalation on the wax surface.Past method commonly used is meal, the Graphite Powder 99 with the metal or alloy material, be sprinkling upon the surface of wax, with appropriate means this meal sticked to the wax surface equably again and form continuous conducting layers, perhaps electric conduction paint, be sprayed on the wax surface, form the paint film of conduction.

United States Patent (USP) 2,932,609 have described with Virahol graphite suspension dipping wax-pattern core, after the remaining solvent evaporates of wax-pattern wicking surface, on the wax-pattern wicking surface, generate one deck equadag coating, and then immerse the isopropanol suspension that is added with iron powder, behind the solution evaporation, on the wax-pattern wicking surface, generate second layer coating, and then the core rod that will handle immerses copper-bath, the formation copper film.Japanese Patent-8031140 invention is the wax-pattern core to be immersed contain in the aqueous solution of Palladous chloride and polyvinyl alcohol, and at room temperature after the drying, its surface just covers the last layer hydrophilic coating, carries out electroless plating again.

Described in Japanese Patent-8031141 invention: the wax-pattern core is immersed earlier in the mixing solutions of trichloroethane and Virahol, and at room temperature after the drying, the wax-pattern wicking surface covers the last layer hydrophilic coating, and then copper facing.

All there are some shortcomings in the method for above-mentioned wax surface metalation, in wax surface coated layer of metal powder or coating, all is difficult to guarantee the consistence of these mantle thickness; This will cause the wax-pattern dimensional precision to descend, the lines on surface distortion, thereby be unsuitable for the electroforming process of precision metallic goods.

The objective of the invention is the roughening solution with special formulation, at room temperature wax is carried out chemical roughen and handle, is that available general method is carried out sensitization, activation and electroless plating then.

The prescription of chemical roughing solution of the present invention is as follows:

K ₂Cr ₂O ₇10～60 grams per liters

CrO ₃30～100 grams per liters

H ₂SO ₄500～850 milliliters/liter

Chemical roughen is handled and can at room temperature be carried out, and under 5～35 ℃ envrionment temperature, all has good alligatoring effect.Wax treatment time in chemical roughing solution is 30～300 seconds.

Chemical roughing solution of the present invention can directly form conductive layer after wax is carried out alligatoring on the wax surface, not additional intermediate material layer; The wax-pattern of handling in this roughening solution, metal level can be very securely attached on the wax-pattern surfaces, and can need not heat in the solution that contains copper sulfate 50～250 grams per liters and sulfuric acid 10～100 grams per liters, are 0.1～2.5A/dm in cathode current density ²Copper facing under the condition.

Advantage of the present invention is as mentioned below:

Handle wax-pattern with the chemical roughing solution that the present invention describes, can not damage or destroy the details of wax-pattern surface shape, the subsides die face of the conductive metal film that obtains can reproduce the wax-pattern surface details realistically.Behind this solution-treated wax-pattern, the color of the subsides die face of the conductive metal film that obtains is the true qualities of this kind metal.Also there is the compound wax-pattern of other metallic surface simultaneously for the surface, uses solution-treated of the present invention, can access the successive conductive metal film in its surface.When compound wax-pattern surface also exists glass or ceramic surface, use this solution-treated, also can obtain the successive conductive metal film in its surface.

Realize that mode of the present invention is as follows:

At first, greasy dirt on the wax-pattern is cleaned up, general available 2～3% water-detergent solution, at room temperature soak wax-pattern, also available cloth soaks solution to be cleaned, but does not damage wax-pattern, for removing washing composition, again the wax-pattern core is placed in the clear water and cleans, make its drying after, can be placed in the roughening solution and handle.The prescription of roughening solution is:

K ₂Cr ₂O ₇40～45 grams per liters

CrO ₃45～50 grams per liters

H ₂SO ₄500～600 milliliters/liter

The temperature of roughening solution is a room temperature, and when significantly being lower than 20 ℃ as if temperature, the treatment time need extend; If when temperature was significantly higher than 30 ℃, the treatment time need suitably shorten; The temperature of roughening solution is best in 20～25 ℃ of scopes.Wax-pattern is in 20～25 ℃ solution, and the roughening treatment time is 90～300 seconds, and the roughening treatment time removes outside the Pass temperature with roughening solution has, and is also relevant with the prescription of wax.Wax-pattern cleans in the cold water that flows, then at SnCL through after the roughening treatment ₂Carry out sensitization in the solution, in activated solution, carry out activation treatment, in chemical plating solution metal-coated membrane and metallizing back-up coat, carry out electroforming at last again.

When compound wax-pattern surface also had metallic copper or silver layer surface simultaneously, the roughening solution prescription was as follows:

K ₂Cr ₂O ₇10～15 grams per liters

CrO ₃30～40 grams per liters

H ₂SO ₄760～800 milliliters/liter

The roughening treatment time is 30～90 seconds, and other condition is identical with last example.

When compound wax-pattern surface also had glass, pottery, chromium degree layer, nickelalloy, nickel coating or stainless steel surface simultaneously, the roughening solution prescription was as follows:

K ₂Cr ₂O ₇55～60 grams per liters

CrO ₃80～100 grams per liters

H ₂SO ₄800～850 milliliters/liter

The roughening treatment time is 30～90 seconds, and other condition is identical with last example.

Claims (5)

1, a kind ofly before electroforming, makes the metallized chemical roughing treatmenting solution of wax-pattern wicking surface, it is characterized in that the alligatoring solvent is by K with chemical process ₂Cr ₂O ₇, CrO ₃, H ₂SO ₄Form.

2, the chemical roughing treatmenting solution of wax according to claim 1 is characterized in that, the chemical roughing solution formula rate of wax is as follows:

K ₂Cr ₂O ₇10～60 grams per liters

CrO ₃30～100 grams per liters

H ₂SO ₄500～850 milliliters/liter

3, the chemical roughing treatmenting solution of wax according to claim 2 is characterized in that, the chemical roughing solution formula rate of wax is as follows:

K ₂Cr ₂O ₇40～45 grams per liters

CrO ₃45～50 grams per liters

H ₂SO ₄500～600 milliliters/liter

4, the chemical roughing treatmenting solution of wax according to claim 2 is characterized in that, the chemical roughing solution formula rate of wax is as follows:

K ₂Cr ₂O ₇10～15 grams per liters

CrO ₃30～40 grams per liters

H ₂SO ₄760～800 milliliters/liter

5, the chemical roughing treatmenting solution of wax according to claim 2 is characterized in that, the chemical roughing solution formula rate of wax is as follows:

K ₂Cr ₂O ₇55～60 grams per liters

CrO ₃80～100 grams per liters

H ₂SO ₄800～850 milliliters/liter