JP2937036B2 - Manufacturing method of chemisorption membrane - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a chemically adsorbed film in which an alkylsiloxane or fluoroalkylsiloxane compound is adsorbed on the surface of a base material, and the siloxane compound is re-adsorbed to improve the durability by eliminating pinholes. It relates to a manufacturing method.

[0002]

2. Description of the Related Art As a method of modifying the surface of a substrate, for example, a method of coating a suspension of a fluorocarbon polymer or a fluorine-based silane coupling agent to impart water repellency, oil repellency, and stain resistance, lubrication, and the like. Methods of coating waxes to impart properties are generally well known.

[0003]

However, the coating film obtained by the conventional method has a weak bonding force with the substrate, so that the surface of the substrate is ground before coating and the coating agent is used to secure the adhesion. However, it was not possible to utilize the surface state and color of the substrate as it was, because of the addition of modifiers and pigments. In addition, since firing at a high temperature was necessary, application to plastic or the like was impossible. Recently,
A method of providing a chemisorption film corresponding to these coatings on the surface of a substrate to improve the adhesion of the substrate has been adopted. However, since the chemical adsorption film has a pinhole, desorption of the chemical adsorption film due to corrosion of the base material or the like proceeds from the pinhole, and there is a problem in durability.

The present invention solves these problems. After adsorbing an alkylsiloxane or fluoroalkylsiloxane compound on the surface of a substrate, the siloxane compound is re-adsorbed to reduce pinholes, thereby improving durability. It is an object to provide a method for providing an improved chemisorption film.

[0005]

The first means of the present invention for achieving the first object is a degreasing step of degreasing a substrate, an alumite treatment step of performing an alumite treatment after degreasing, and the alumite treatment Provided is a method for producing a chemisorption film, comprising: an adsorption step of adsorbing an alkylsiloxane or a fluoroalkylsiloxane compound on a surface after the step; and a washing step of washing the surface after the adsorption step.

According to a second aspect of the present invention, there is provided a method for producing a chemisorption film having a repetition step of repeating the adsorption step and the washing step a plurality of times in addition to the first means.

A third means of the present invention is a degreasing step of degreasing the substrate, an alumite treatment step of performing alumite treatment after degreasing, and adsorbing an alkylsiloxane or fluoroalkylsiloxane compound on the surface after the alumite treatment step. And a re-adsorption step of re-adsorbing the siloxane compound thereafter.

[0008]

When a substrate is immersed in a non-aqueous solvent containing an alkylsiloxane or fluoroalkylsiloxane compound under a nitrogen atmosphere at about room temperature, these compounds react with hydroxyl groups or water adsorbed on the substrate. Adsorbs on the substrate. Thereafter, when the substrate is immersed in water at a temperature of about room temperature, hydroxyl groups or water is adsorbed on these adsorbed compounds. After drying, the series of adsorption operations is repeated and re-adsorbed by the siloxane compound, thereby obtaining a substrate having a chemically adsorbed film whose surface is completely covered.

In this state, compared to a state in which an alkylsiloxane or a fluoroalkylsiloxane compound is simply adsorbed on the substrate surface to form a chemically adsorbed film, these chemicals do not penetrate and cannot be adsorbed, and the resulting chemical is formed. A siloxane compound having a smaller molecular weight than these compounds penetrates into the pinholes of the adsorption film and is re-adsorbed to form a pinhole-less chemical adsorption film. Therefore, the durability of the chemically adsorbed film is improved by preventing corrosion of the base material from the pinhole.

Further, since the chemical adsorption film is formed on the base material by a chemical bond called a siloxane bond, the chemical adsorption film does not peel off even if the surface is repeatedly washed. Also, the chemical adsorption film does not impair the feeling of the substrate.

[0011]

【Example】

(Embodiment 1) Hereinafter, a specific embodiment of the method for producing a chemically adsorbed film of the present invention will be described with reference to FIG.

Alumite is used as the base material 1 in a nitrogen atmosphere at about room temperature, and heptadecafluorodexyltrichlorosiloxane is used as the fluoroalkylsiloxane compound 2 and n-hexadecane / chloroform is used as a non-aqueous solvent of 90/10 (weight ratio). ) Using ^10-2 mol /
1 (A in FIG. 1), the fluoroalkylsiloxane compound 2 reacts with the hydroxyl group 3 or water 4 adsorbed on the substrate 1 and adsorbs on the substrate (B in FIG. 1).
Thereafter, when the substrate is immersed in water, the hydroxyl group 3 or water 4 is adsorbed on the adsorbed fluoroalkylsiloxane compound 2 (C in FIG. 1). After further drying, this series of adsorption operations is repeated and re-adsorbed using tetrachlorosilane as the siloxane compound 5 (D in FIG. 1), and finally, the chemically adsorbed film 6 completely covering the substrate surface is obtained. Formed (E in FIG. 1). Since the chemically adsorbed film is made of fluoroalkylsiloxane, this substrate also has water repellency, oil repellency, and antifouling properties.

[0013] In order to evaluate the chemisorbed film obtained according to the present invention, it was left in boiling water for 2000 hours. During this time, every 200 hours, dirt on the substrate was washed with a 2.5% by weight aqueous citric acid solution by boiling, and 4 μm of water was applied to the surface of the substrate.
The contact angle of water when 1 was dropped was measured, and the results are shown in (Table 1).

[0014]

[Table 1]

From these results, it is understood that the durability of the chemically adsorbed film is improved by re-adsorbing the siloxane compound. It is also found that the greater the number of re-adsorptions, the better the durability, and the object of the present invention can be achieved.

Examples of the alkyl siloxane compound to be used in the present invention, methyltrichlorosilane or the like, the general formula _{C n H 2n-m + 1} F m -SiX of heptadecafluoro dextropropoxyphene sill trichlorosiloxane such as fluoroalkyl siloxane compound
₃ (n = 1, 2, 3,..., M = 0, 1, 2,... 2n + 1; X = halogen atom), and siloxane compounds such as tetrachlorosilane and hexachlorodisiloxane The general formula of Si _n O
_n-1 X _{2n + 2} (n = 1, 2, 3,...; X = halogen atom), and a linear compound is preferable for increasing the adsorption density. Further, any organic solvent having no active hydrogen that reacts with the siloxane compound may be used as the non-aqueous solvent,
For example, for the alkylsiloxane, fluoroalkylsiloxane, or siloxane compound, a hydrocarbon solvent such as n-hexadecane, chloroform,
Formula and halogenated hydrocarbon solvents such as 2,2-trifluoroethane _{C n H 2n-m + 2} X m (n = 1,2,3, ··· m = 0,1,2, ···
2m + 2; X = haloken atom), or a mixture thereof as desired. Further, as the base material, a metal such as alumite, stainless steel, glass, and other plastics can be used as long as they can withstand the above-mentioned solvents, and the performance shown above can be obtained.

(Example 2) An example in which a product obtained by using the method for producing a chemically adsorbed film of the present invention is applied to a rice cooker will be described.
The operation of this configuration will be described based on the cross-sectional view of the configuration of the rice cooker shown in FIG. Reference numeral 3 denotes an inner lid made of an alumite substrate on which the chemically adsorbed film shown in Example 1 is formed, and the inner lid is attached to an outer lid 4 which can be opened and closed by a hinge 5 at an upper part of the main body 1 and 1. 6 is water and rice stored in the pot 2. Reference numeral 7 denotes a power cord for supplying power to the main body 1.

Next, the operation will be described. In a state where power is supplied by the power cord 7 and water and rice in the pot 2 are heated from the bottom and cooked in a state of being cut off from the outside by the inner lid 3 and the outer lid 4, the heat-retaining state is always maintained. Therefore, the above-described chemisorption film is held in a state of being constantly in contact with hot water or steam. The rice cooker is used in a state where this operation is repeated.

In order to test the performance of the chemisorption film in practical use, a series of operations of putting rice in water and rice, cooking the rice, and keeping the temperature for 60 minutes was repeated 1000 times. 10 during this time
Every 0 times, the inner lid 3 was cleaned by rubbing 100 times back and forth with a sponge impregnated with an undiluted detergent solution, and the state of the base material and the contact angle of water were measured in the same manner as described above, and the result was determined as ( The results are shown in Table 2).

[0020]

[Table 2]

From these results, it can be seen that the chemically adsorbed film composed of the fluoroalkylsiloxane compound on the inner lid has an antifouling property,
It turns out that it is excellent in anticorrosion property, and that its durability improves by re-adsorbing a siloxane compound. It is also found that the greater the number of re-adsorptions, the better the durability, and the object of the present invention can be achieved.

[0022]

As is apparent from the above examples, according to the present invention, after the alkylsiloxane or fluoroalkylsiloxane compound is adsorbed on the base material, the siloxane compound is re-adsorbed to reduce the pinholes. Thereby, a chemically adsorbed film having improved durability can be provided. In this state, compared to the state in which the alkylsiloxane or fluoroalkylsiloxane compound is simply adsorbed on the surface of the base material to form a chemically adsorbed film, these chemicals do not penetrate and cannot be adsorbed. A siloxane compound having a smaller molecular weight than these compounds penetrates into the pinhole and is re-adsorbed to form a pinhole-less chemical adsorption film. Therefore, the durability of the chemically adsorbed film is improved by preventing corrosion of the base material from the pinhole. Further, since the chemical adsorption film is formed on the base material by a chemical bond called a siloxane bond, the chemical adsorption film does not peel off even if the surface is repeatedly washed. Also, the chemical adsorption film does not impair the feeling of the substrate.

Further, by adding a step of re-adsorbing the siloxane compound to the step of adsorbing the alkyl siloxane or fluoroalkyl siloxane compound on the surface of the base material, a chemically adsorbed film can be easily manufactured.

By forming the chemically adsorbed film with a fluoroalkylsiloxane compound, a cooker having a water-repellent, oil-repellent, and antifouling container inner surface can be produced, and even if sticking of the food occurs, it can be easily washed. And can be easily released, maintaining the beauty and cleanliness for a long time.

[Brief description of the drawings]

FIG. 1 is a chemical adsorption film of the present invention and a method for producing the same.

FIG. 2 is a configuration diagram of a rice cooker according to one embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 1 base material 2 fluoroalkylsiloxane compound 3 hydroxyl group 4 water 5 siloxane compound 6 chemisorption film

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI B05D 7/14 B05D 7/14 C 7/24 302 7/24 302D 302Y C23G 1/00 C23G 1/00 // A47J 27/00 103 A47J 27/00 103N C11D 7/50 C11D 7/50 (72) Inventor Mamoru Soga 1006 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. 1006 Matsushita Electric Industrial Co., Ltd. (72) Inventor Kazufumi Ogawa 1006 Okadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References JP-A-8-120490 (JP, A) 7-188983 (JP, A) JP-A-5-311116 (JP, A) JP-A-56-13065 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C25D 11/18 308

Claims (3)

(57) [Claims] 1. A degreasing step of degreasing a substrate, an alumite treatment step of performing an alumite treatment after degreasing, an adsorption step of adsorbing an alkylsiloxane or a fluoroalkylsiloxane compound on the surface after the alumite treatment step, and A method for producing a chemical adsorption film, comprising: a cleaning step of cleaning a surface. 2. The method according to claim 1, further comprising a repeating step of repeating the adsorption step and the washing step a plurality of times. 3. A degreasing step of degreasing a substrate, an alumite treatment step of performing an alumite treatment after degreasing, an adsorption step of adsorbing an alkylsiloxane or a fluoroalkylsiloxane compound on a surface after the alumite treatment step, and thereafter further comprising a siloxane. A process for re-adsorbing the compound.