JP3137440B2 - 6-perfluoroalkylanilino-1,3,5,-triazine-2,4-dithiol or metal salt thereof and process for producing them - Google Patents

Description

[Detailed description of the invention]

[0001]

FIELD OF THE INVENTION The present invention relates to novel 6-substituted-1,3,5-
The present invention relates to a triazine-2,4-dithiol derivative and a method for producing the same. More specifically, a novel 6-substituted-1,3,5-triazine-2,4-
It relates to a dithiol derivative and a method for producing the same.

[0002]

2. Description of the Related Art 1,3,5-triazine-2,4-dithiol derivatives form films on metal surfaces by means of immersion, electrolytic polymerization, tribopolymerization, etc., and improve their corrosion resistance and adhesiveness. (Kagaku Kogyo Vol. 42, p. 1005, 1991; Practical Surface Technology Vol. 35, p. 595, 1988), and some of these techniques have already been put into practical use. has been made

[0003] Namely, 1,3,5-triazine-2,4-dithiol derivatives have excellent reactivity and film-forming properties with respect to metal surfaces, and are used in electropolymerization treatments, tribopolymerization treatments, and the like. High-speed and large-volume processing is possible. Therefore, it is characterized by being able to process from small metal parts to large-sized materials such as wires and plates with high productivity.

However, conventionally used 1,3,5-
Since the 6-position substituent of the triazine-2,4-dithiol derivative is a group mainly composed of C, H, S, etc. such as dibutylamino group, anilino group, dioctyl group, diallyl group, and mercapto group, A disadvantage is that the treated metal surface is easily contaminated by organic matter and dust containing these constituent elements suspended in the air. Such fouling is inherent to the constituent elements, and it is almost impossible to improve fouling resistance without changing the constituent elements.

On the other hand, for the purpose of improving the contamination resistance of metal surfaces, fluorine-based silane coupling agents and phosphoric acid-based treatment agents have been developed and are commercially available. is not sufficient, the original effect is not exhibited. Moreover, since these treatment agents can be used for surface treatment only by an immersion method, there is a limit to working efficiency, and therefore they cannot be said to be general-purpose treatment techniques.

[0006] The problems seen with such processing agents are derived from the chemical properties of the processing agents, and are not properties that can be achieved by improving the processing method. , can be said to be an inherent drawback of the compounds used. Therefore, it is completely impossible to apply the electrolytic polymerization method and the tribopolymerization method to the silane coupling agent and the phosphoric acid-based treatment agent.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to make it possible to introduce the properties of a fluorine-based compound into a metal surface, which has the lowest surface energy and is less susceptible to contamination by organic substances and substances with high surface energy. In addition, a novel type with excellent reactivity and film-forming properties on metal surfaces.
An object of the present invention is to provide a 1,3,5-triazine-2,4-dithiol derivative.

[0008]

DISCLOSURE OF THE INVENTION The object of the present invention is to:
6-perfluoroalkylanilino-1,3,5-triazine-2,
Alkali metal or alkaline earth metal salts of 4-dithiols

[Chemical 1] (where Rf is a straight or branched chain perfluoroalkyl group having 4 to 18 carbon atoms, and M, M' are alkali metal salts or 1/2 alkaline earth metal salts). .

[0009] Such a metal salt is synthesized through the following steps. (1) Reaction of cyanuric chloride and perfluoroalkylaniline to obtain 6-perfluoroalkylanilino-1,3,5-triazine-2,4-dichloride. This reaction converts perfluoroalkylanilines, generally p-perfluoroalkylanilines, synthesized from 1-iodinated perfluoroalkanes and iodoanilines, generally p-iodoanilines, using the Ullmann reaction, into a weak solution such as sodium carbonate. It is carried out by reacting with cyanuric chloride in the presence of a base. (2) 6-perfluoroalkylanilino-1,3,5-triazine-2,4-dichloride is reacted with alkali metal sulfides such as sodium hydrogen sulfide, potassium hydrogen sulfide, sodium sulfide and potassium sulfide to obtain 6 -reaction to give perfluoroalkylanilino-1,3,5-triazine-2,4-dithiol. (3) reacting 6-perfluoroalkylanilino-1,3,5-triazine-2,4-dithiol with an alkali metal or alkaline earth metal hydroxide to form an alkali metal salt or alkaline earth metal thereof; A reaction that yields a salt. Since 2,4-dithiol does not dissolve in water, this reaction is carried out by reacting it with lithium hydroxide, sodium hydroxide, potassium hydroxide, barium hydroxide, etc. using an alcohol such as methanol or ethanol as a solvent. . At this time, a monometallic salt or a dimetallic salt is formed depending on the molar ratio of the metal hydroxides used.

The metal salt of 6-perfluoroalkylanilino-1,3,5-triazine-2,4-dithiol thus obtained is dissolved in an alcohol such as methanol or ethanol and subjected to metal treatment. Prepared as a liquid. The prepared metal treatment solution is subjected to surface treatment of metals such as iron, stainless steel, aluminum, nickel, copper, brass, bronze, gold, and silver by an immersion method, an electrolytic polymerization method, a tribopolymerization method, or the like.

In the immersion method, about 20 to 18
Immersion treatment is performed at 0°C for about 0.1 to 1 hour. In the electropolymerization method, the above metal treatment solution is placed in an electrolytic cell equipped with a working electrode (metal plate to be surface-treated) and a counter electrode (platinum plate, etc.), and the current density is about 0.001 to 100 mA/cm ² for about 1 second. ~about
It is electropolymerized for about 20 minutes. In addition, in the tribopolymerization method, the metal surface is tribopolymerized by using a dithiol metal salt as a lubricant during metal working and simultaneously performing working and surface treatment.

[0012]

[action] and

Effect of the Invention Due to its low surface energy, a fluorine compound cannot form a stable film even if it is applied or adhered to the surface of a material having a high surface energy such as a metal. However, if a metal surface is chemically treated with a fluorine compound to change to a low-energy surface, it becomes possible to apply a fluorine-based paint, form a stable coating film, and bond the two together.

[0013] From this point of view, in order to improve the contamination resistance of the metal surface, it is necessary to modify the metal surface to a low-energy surface. In order to obtain a metal with a low energy surface, a treating agent having high chemical reactivity with the metal and having functional groups to provide a low energy film will be required.

[0014] As a compound that achieves these two objectives, a metal salt of 6-perfluoroalkylanilino-1,3,5-triazine-2,4-dithiol is provided by the present invention to provide resistance to metal surfaces. By using such compounds that form fouling fluorine-based films, non-fouling metals can be produced in large quantities at low cost.

[0015]

EXAMPLES The present invention will now be described with reference to examples.

Example 1 Into a 300 ml three-necked flask, 9.23 g (0.00
5 mol) and 100 ml of acetone were charged and stirred to form a solution, and then 50 ml of an acetone solution in which 0.051 mol of p-perfluoroalkylaniline had been dissolved was added to 60 ml while maintaining the temperature at 5°C (+2)°C with crushed ice. It was added dropwise over a period of minutes. Then, while maintaining this temperature, 50 ml of an aqueous solution containing 4 g (0.04 mol) of sodium carbonate was added dropwise over 60 minutes, followed by stirring for 3 hours.

Return the temperature of the reaction solution to room temperature (30° C.), and
After stirring for 3 hours to complete the reaction, the reaction mixture was poured into 500 ml of crushed ice to give 6-(p-perfluoroalkylanilino)-1,
3,5-Triazine-2,4-dichloride was obtained as a white precipitate with a crude yield of 95% or more.

0.03 mol of this dichloride and 100 ml of dimethylformamide were placed in a 500 ml three-necked flask, stirred to form a solution, and heated to 50.degree. To this, 7.2 g (0.03 mol) of sodium hydrogen sulfide (purity 70%) was added to 60
A solution dissolved in 50 ml of volume % dimethylformamide aqueous solution was added dropwise over 20 minutes, the temperature of the reaction solution was raised to 70°C, and after stirring for 3 hours, the temperature was lowered to room temperature.

6-(p-perfluoroalkylanilino)-1,3,5 was obtained by adding dropwise 1% hydrochloric acid to the reaction mixture until the pH reached 3.
-Triazine-2,4-dithiol is obtained as a white precipitate in a crude yield of >95%. This was recrystallized with isopropanol.

0.03 mol of this dithiol and 1.2 g (0.03 mol) of sodium hydroxide are dissolved or dispersed in 200 ml of methanol and the methanol is distilled off under reduced pressure. When most of the methanol had been distilled off, the residue was washed with 200 ml of diethyl ether to give 6-(p-perfluoroalkylanilino)-1,3,5-triazine-2,4-dithiol.
White crystals of monosodium were obtained with a yield of more than 90%.

The melting points and elemental analysis values (calculated values in parentheses) of the dithiols obtained in the above series of steps are shown in Table 1 below.
shown in Table 1 Elemental analysis Rf base melting point (°C) C (%) N (%) SH (%) CF ₃ (CF ₂ ) ₂ CF ₂ - 243-6 34.26 12.36 13.67 (34.46) (12.33) (14.12) CF ₃ (CF2) ₄ CF2 - 238 to ₄₀ 32.78 9.99 11.05 (32.49) (10.11) (11.57) _{CF3 (} CF2) ₆ CF2 - 222 to ₄ 31.44 8.76 8.56 ( _31.20 ) (8.56) (9.80)

[0022] These dithiols and their monosodium salts are both soluble in methanol, water, etc., and have the following characteristic absorption in the infrared absorption spectrum. Dithiols: 1150, 1200, 1350, 1420, 1590, 16
30 cm ^-1 monosodium salt: 1150, 1210, 1300, 1370, 1485, 16
10cm ^-1

Wetting property of copper plate by immersion treatment ) was dissolved in 1 L of methanol to prepare a treatment solution. In 100 ml of this treatment solution, a mirror-finished copper plate (30×60×1 mm; manufactured by Nippon Electric Lamp Industry Co., Ltd.) was immersed for 10 minutes at a predetermined temperature for immersion treatment.

After the treatment, the contact angle of the copper plate surface with respect to water or CH ₂ I ₂ was measured using a contact angle measuring instrument G-1 manufactured by Elma Optical Co.
34, 19, 1971) to calculate the surface energy. The measured and calculated results are shown in Table 2 below. In addition, in this Table 2, untreated copper plate (reference example) and
Results for a copper plate (comparative example) similarly treated with 6-dodecylamino-1,3,5-triazine-2,4-dithiol are also shown. Table 2 Treatment temperature Contact angle (°) Surface energy example (°C) Water CH ₂ I ₂ γ (dyne) γD (erg/cm ² ) γP (erg/cm ² ) Example 20 107 83 27.6 26.7 0.9 〃 60 114 96 19.8 19.3 0.5 Reference example - 88 34 50.6 46.0 4.8 Comparative example 60 95 76 32.3 28.1 4.2

From the above results, the following can be said. Compared to the untreated copper plate (reference example), the copper plates immersed with triazines (examples and comparative examples) were more sensitive to water and CH ₂ I
In both cases of ₂ , the contact angle is high, and it can be seen that the surface has changed to a surface that is difficult to wet. Also, those using 6-dodecylamino-1,3,5-triazine-2,4-dithiol
(Comparative Example) has a lower surface energy than the untreated one (Reference Example), but this value is higher than that of the perfluorinated alkyl group (Example), and the alkyl group is perfluorinated. This makes it possible for the first time to obtain a surface that is less susceptible to contamination of 30 dynes or less. The higher the treatment temperature, the lower the surface energy. This is thought to be because the higher the treatment temperature, the easier the formation of the film.

Wetting property of copper plate by electropolymerization ) was dissolved in 1 L of methanol to prepare a treatment solution. This treatment solution is applied to the working electrode (30 × 60
× 0.2 mm mirror-finished iron plate) and counter electrode (50 × 50 ×
Electrolysis cell equipped with a 0.2 mm platinum plate (Chemical Industry Vol. 42, No. 1
005, 1991), electropolymerization was carried out at a predetermined current density for 2 minutes, and the contact angle and surface energy of the working electrode surface were measured and calculated in the same manner as described above. The results obtained are shown in Table 3 below. In addition, in Table 3, 6-
The results for the working electrode surface similarly electropolymerized using dodecylamino-1,3,5-triazine-2,4-dithiol are also shown. Table 3 Current Density Contact Angle (°) Surface Energy Example (mA/cm ² ) Water CH ₂ I ₂ γ (dyne) γD (erg/cm ² ) γD (erg/cm ² ) Example 0.2 108 87 23.7 23.0 0.7 Same as above 2 118 100 16.9 16.6 0.3 Comparative example 2 97 78 31.0 26.3 3.7

From the above results, the following can be said. Electropolymerization can generally exhibit low surface energy because the molecular arrangement can be controlled, but the examples show significantly lower surface energies than this comparative example and the immersion treated metal surface.

──────────────────────────────────────────────────── ──── Continuation of the front page (58) Fields investigated (Int.Cl. ⁷ , DB name) C07D 251/46 C23C 26/00 C25B 3/10 C25D 13/04 CA (STN) REGISTRY (STN)

Claims (6)

(57) [Claims] [Claim 1] 6-Perfluoroalkylanilino-1,3,5
-triazine-2,4-dithiol or its alkali metal or alkaline earth metal salts. 2. A process for producing 6-perfluoroalkylanilino-1,3,5-triazine-2,4-dichloride, which comprises reacting perfluoroalkylaniline with cyanuric chloride. 3. 6-Perfluoroalkylanilino-1,3,5
- A process for the preparation of 6-perfluoroalkylanilino-1,3,5-triazine-2,4-dithiol, which comprises reacting triazine-2,4-dichloride with an alkali metal sulfide. 4. 6-Perfluoroalkylanilino-1,3,5
- characterized by reacting triazine-2,4-dithiol with an alkali metal or alkaline earth metal hydroxide
6-perfluoroalkylanilino-1,3,5-triazine-2,
A method for producing an alkali metal salt or an alkaline earth metal salt of 4-dithiol. 5. The organic solvent solution of the metal salt according to claim 1
A surface treatment agent for a metal plate comprising: 6. Immersion treatment with the surface treatment agent according to claim 5 ,
Characterized by electrolytic polymerization treatment or tribopolymerization treatment
The processing method of the metal plate to do .