JPH0399088A - Synthesis method of organoplatinum compounds - Google Patents

Abstract

PURPOSE:To obtain the subject compound, suitable as a raw material for thin film-forming materials in the electronic industry and having superior preservation stability, etc., when dissolved together with a metal resinate, etc., in a solvent by reacting a platinate with a specific compound, followed by a specific treatment of the reaction mixture. CONSTITUTION:First, a limonene mercaptan is added to an aqueous solution of a platinate [example; tetrachloroplatinic acid (II)] and sufficiently agitated and the reaction mixture is extracted with chloroform. Then the chloroform layer is separated and washed with water, followed by dehydration and filtration. Then the filtrate chloroform layer is heated to evaporate the chloroform and provide an oily substance. Finally, n-hexane is added to the oily substance to afford a crystal of the objective compound. To 1mol platinate, are preferably added 2-4mol, and 1-2 times of a stoichiometric amount of the limonene mercaptan.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention is applicable to various platinum-containing catalysts, conductors for electronic component materials, resistors, and corrosion-resistant films. This invention relates to a method for synthesizing platinum limonene mercaptide as an organic platinum compound that is a raw material.

(Prior art and its problems) Conventionally, platinum as a raw material for paste has been prepared by dissolving inorganic compounds such as chloroplatinate as fine metal powder or platinum compounds in alcohol etc. Inorganic compounds such as platinates generate harmful gases that can damage the base material during thermal decomposition, and when alcohol, etc. evaporates, they precipitate as crystals and are unstable, forming a platinum film. There are some things that are lacking.

In addition, what is called water platinum, which is used for decoration, can be made into a thin platinum film by applying platinum as a solution, drying, and firing, but its synthesis method is from sulfur balsam and platinum salts. The raw material is a synthesized organic platinum compound.

However, the turpentine used in the synthesis of sulfur balsam is a natural product containing rosin and several types of terpenes.
The platinum content in the synthesized platinum compound is bulk, and when mixed with other metal resinates and various resins as binders and dissolved in an organic solvent, it dissolves in a common organic solvent and is stable and uniform. Although it remains in a liquid state, it is susceptible to deterioration due to light, moisture, etc., and does not fully meet the demands of use.

(Objective of the Invention) The present invention has been made to solve the conventional drawbacks, and it can be dissolved in an organic solvent with other metal resinates, etc., and maintain a stable state even when stored for a long period of time, even in the form of a solution. The platinum content as a platinum compound is also relatively high, with little variation.
The present invention provides a method for synthesizing an organic platinum compound that does not damage a base material during the process of thermally decomposing it into platinum.

(Means for Solving the Problems) The present invention includes a first step of adding limonene mercaptan to an aqueous solution of a platinate salt, thoroughly stirring the mixture, and then adding chloroform for extraction, and separating the chloroform layer. a second step of washing with water, dehydration and filtration; a third step of heating the filtered chloroform layer to evaporate the chloroform to obtain an oily substance; and adding the extracted substance to n-hexane. A method for synthesizing an organoplatinum compound, characterized in that it consists of a fourth step of producing crystals, in which the crystals are filtered and then dried to yield pale yellow crystals of platinum limonene butide.

The details of the present invention will be explained below.

Aqueous solutions of platinates include tetracroplatinate (II) acid, potassium tetracroplatinate (TI), hexacroplatinate (IV) acid, sodium hexateplatinate (IV), potassium hexacroplatinate (IV). , ammonium hexagonal platinate (IV), dissolved in a small amount of distilled water, is used.

The amount of platinate and limonene mercaptan to be added is preferably 2 to 4 moles of limonene mercaptan per 1 mole of platinate, about 1 to 2 times the chemical theoretical equivalent.

The aqueous solution of the platinum salt and limonene mercabutane are added and stirred, but it is necessary to do this at room temperature for at least 24 hours.

If the stirring and reaction described above are insufficient, the yield of the desired platinum compound will decrease.

Then, an appropriate amount of chloroform is added, stirred, extracted into chloroform, and the chloroform layer is separated.

Since the separated chloroform layer contains impurities, it is washed with distilled water, but the end point of the washing is when the PH of the separated distilled water is 5 to 5 after washing the chloroform layer.
It is necessary to continue until reaching 7.

After sufficient washing with distilled water, an appropriate amount of powder such as sodium sulfate (anhydrous) is added to remove water contained in the chloroform layer, mixed gently, and then separated by filtration.

Next, the chloroform layer separated by filtration is transferred to a distillation device such as an evaporator, and the chloroform is evaporated at 40 to 60°C to obtain a porridge-like substance.

When the porridge-like substance is added to n-hexane with stirring, pale caustic-colored crystals are formed.

After filtering the pale yellow crystals produced in Section 2 and drying them under reduced pressure in a desiccator, the platinum content was 29 wt%.
Crystals of platinum limonene mercaptide are obtained.

Incidentally, the oily substance obtained after evaporating the chloroform obtained in the above process can also be used as a raw material for the platinum thin film forming material.

Examples related to the present invention will be described below, but the examples are not intended to limit the present invention.

(Example 1) 57.1 g of hexagonal platinum (IV) acid and 12.1 g of distilled water.
5i and dissolve it, add limonene mercabutane 75
．． 4 g of the mixture was added and stirred at room temperature for 24 hours, then 1001 nl of chloroform was added, stirred and extracted with chloroform, left to stand, and the chloroform layer was separated.

300 ml of distilled water was added to the separated chloroform layer, stirred, allowed to stand, and the operation of separating the distilled water layer was performed 10 times, and the pH of the separated distilled water was 6.

Add 20 g of sodium sulfate (anhydrous) to the chloroform layer washed with distilled water, stir gently, and filter to remove water in the chloroform layer. Next, transfer the filtrate to an evaporator and evaporate chloroform l1 at 60°C. An oily substance was obtained. The oily substance was added to n-hexane 11 with stirring to produce pale yellow crystals, which were collected by filtration using a glass filter and placed in a desiccator at room temperature under reduced pressure. After drying, 35 g of pale bitter-colored crystals were obtained, which was chemically analyzed and found to have a platinum content of 28.9 wt%.

From the above results, the purity as platinum limonene mercaptide was 90%, and the yield as platinum was 47%.

(Examples 2 to 4) Example 2 was operated in the same manner as Example 1, except that a tetrachloride platinum (n) acid solution containing 21.6 g of platinum was used.

Example 3 is 46 g of potassium tetrachloroplatinate (II)
The procedure was repeated in the same manner as in Example 1, except that 400 ml of distilled water was added and dissolved.

Example 4 is hexagonal sodium platinate (IV) 62
The procedure was repeated in the same manner as in Example 1, except that 20 ml of distilled water was added to g and dissolved.

The above results were as shown in the table below.

〔result〕

(Example 5) Platinum limonene mercabutide obtained in Example 1 (4.1
Rhodium resinate (0.04g) and bismuth resinate (0.4g) were used as other metal resinates.
2g), antimony resinate (0.08g), asphalt (1,0g) as an organic binder, turbineol (3.0g) as an organic solvent and urea resin (1.0g) as an organic binder.
g) was dissolved in benzyl acetate (0.31 g) to obtain a viscous solution.

The viscous solution can be used as glass glaze, quartz, glass, hollow,
Stainless steel, ceramic 84mm x 64 marks x thickness 1
Coated by screen printing on a substrate of mm and heated to lO at 150°C.
It was dried for 1 minute and then baked at 700°C for 10 minutes to form a platinum thin film.

As a result, the platinum thin films formed on the surfaces of glass glaze, quartz, and glass were shiny, and the platinum thin films formed on the surfaces of hollow, stainless steel, and ceramic were matte.

When a beer test was conducted to confirm the adhesion of the platinum thin film described above, no peeling occurred.

In addition, the prepared ↑-i solution was stored in a brown bottle for 6 months with a tightly stopper, but it remained in a uniform solution state.

(Example 6) The crystals obtained in Examples 2 to 4 were used as other metal resinates such as rhodium resinate, bismuth resin-1, and chromium resinate at 0.5 to 5 Owt%, respectively, and asphalt and urea resin as organic binders at 20 Wt. %, 33 wt% of terpineol and benzyl acetate as organic solvents.
The remaining portion was crystallized to prepare a conditioned solution, and it was confirmed that it became a homogeneous solution.Similar to Example 5, the storage stability for 6 months was confirmed, but no degradation was observed.

In addition, when an oily substance produced during the process of synthesizing platinum limonene mercaptide crystals was printed on a glass substrate, dried, and fired in the same manner as in Example 5, a white thin film was formed in the same way, and the adhesion was preserved. There was no difference in gender either.

(Effects of the Invention) As described above, the present invention can synthesize crystals of platinum limonene mercaptide with stable quality, which have characteristics that cannot be obtained with conventional organic platinum compounds such as water platinum. By mixing and preparing a metal resinate, an organic binder, and an organic solvent, a uniform and appropriate viscosity can be prepared.The platinum content is also relatively high, so when forming a thin film, it is difficult to apply, dry, and bake. It has the effect of being able to obtain a suitable thin film thickness even with a small number of repeated operations, and is extremely useful as a raw material for forming thin films for the electronics industry, such as precise thicknesses and thin film widths.

Claims (1)

[Claims] (1) The first step is to add limonene mercaptan to an aqueous solution of platinum salt, stir well, and then add chloroform for extraction.The second step is to separate the chloroform layer, wash it with water, dehydrate it, and filter it. a third step of heating the filtered chloroform layer to evaporate the chloroform to obtain an oily substance; and a fourth step of adding the oily substance to n-hexane to form crystals. A method for synthesizing an organic platinum compound characterized by: