JPH0753863B2 - Composition for aerosol - Google Patents

Description

TECHNICAL FIELD The present invention relates to an aerosol composition containing a lubricating powder, and more specifically, a die such as an extruder die or a casting die. Among them, it relates to an aerosol composition containing a lubricating powder suitable for use in a die for an aluminum extruder for the purpose of lubrication or release.

(Prior Art) For example, in casting, forging, roll pressing, aluminum extrusion or diamond sintering, when it is necessary to provide mold releasability or lubricity between the die to be used and the object to be treated, the die is used. And / or a lubricant powder such as graphite, boron nitride, mica, molybdenum disulfide, or fluororesin having a releasing property or a lubricating property is adhered to the surface of the object to be treated as a releasing agent or a lubricant. As a method of applying these lubricating powders most easily and allowing them to adhere uniformly,
A method is employed in which a spray can is enclosed in a spray can together with a dispersion medium mainly composed of CFC and a propellant, and sprayed as an aerosol.

(Problems to be Solved by the Invention) However, as the production of CFCs is being regulated due to fear of environmental damage, various compositions for aerosols using a dispersion medium and a propellant instead of CFCs are being studied. Is the dispersibility of the lubricating powder in the dispersion medium, the sprayability during spraying, the drying speed of the coating film formed by spraying and the homogeneity of the coating film, and the adhesion of the lubricating powder to the coating surface. In terms of properties and storage stability, there has not yet been obtained a composition showing satisfactory performance as an aerosol composition for spraying a lubricating powder.

The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, found that an aerosol composition having a specific composition exhibits excellent performance, and arrived at the present invention.

That is, an object of the present invention is to provide an aerosol composition which satisfies the performance required for spraying a lubricating powder in a well-balanced manner such as dispersibility of the lubricating powder in a dispersion medium and sprayability during spraying. It is in.

(Means for Solving the Problems) However, the object of the present invention is to provide an aerosol composition containing a dispersion medium, a lubricating powder, a propellant and an additive, wherein isopropyl alcohol and 1, 1,1
Easily achieved by an aerosol composition characterized in that it comprises trichloroethane, dimethyl ether and / or LPG as the propellant and an anionic surfactant as the additive.

(Operation) Hereinafter, the present invention will be described in detail.

Examples of the lubricating powder used in the present invention include powders such as graphite, boron nitride, mica, molybdenum disulfide, fluororesin and talc, alone or in combination. The particle size of these powders may basically be selected from a wide range as long as they can be used for spraying, but in consideration of jettability, adhesiveness to the coating surface, homogeneity of the coating film, etc. It is preferable to use a powder having a maximum particle size of 15 μm or less, that is, a substantially total amount of the particles having a particle size of 15 μm or less, more preferably 8 μm or less. In addition, if fine powder is used, the surface of the coated object such as metal will not be roughened.

The content of the above-mentioned lubricating powder is 2 with respect to the undiluted solution (hereinafter, simply referred to as "undiluted solution") excluding the propellant that is gaseous at room temperature and pressure from the entire composition for aerosol of the present invention. ~ 20wt
%, More preferably 3 to 10% by weight, a sufficient amount of the lubricating powder can be uniformly applied by a single spray, which is preferable.

The composition for an aerosol of the present invention has one characteristic that it contains both isopropyl alcohol and 1,1,1-trichloroethane as a dispersion medium. Among them, isopropyl alcohol can disperse the lubricating powder well, , 1,1
-Trichloroethane is excellent in terms of dryness of the coating film,
Isopropyl alcohol may be contained in the stock solution in an amount of 6 to 32 wt%, preferably 8 to 25 wt%, and trichloroethane in an amount of 48 to 96 wt%, preferably 55 to 95 wt%. Further, other dispersion mediums may be contained as long as the preferable effects of these two dispersion media are not impaired, and the content ratio of the whole dispersion medium in the stock solution is 70 to 98 wt%, more preferably 80% by weight.
It is preferably about 96 wt%.

In the case of an aerosol composition, it is desirable to stably maintain the colloidal state regardless of the polarity and nonpolarity of the colloidal particles and the polarity / nonpolarity of the fraction medium. As a component of the composition for aerosol of the present invention, it has been found that an anionic surfactant has a great effect of stably maintaining the colloidal state. It can be said that there are numerous types of anionic surfactants, but in the present invention, sulfonic acid type, phosphoric acid ester type,
Carboxylic acid and the like are preferable, and sodium alkyl sulfonate,
Examples include alkylphenol phosphate ester, allyl phosphate ester, and rosin acid soap, which are effective.
The amount added to the stock solution depends on the type of powder, solvent, etc., but is preferably 0.3 to 7 wt%, more preferably 0.5 to 4 wt%.

The stock solution obtained as described above is supplied for spraying by being enclosed in a spray can together with a propellant, but the propellant is compatible with the dispersion medium in the stock solution, has a strong spraying power, and does not agglomerate colloid particles. Is required.

In the case of the aerosol composition of the present invention, dimethyl ether,
The use of LPG or a mixture thereof can meet the above requirements well.

The amount of the propellant to be used needs to be changed to some extent depending on the composition of the stock solution, but a weight ratio of 35 to 220, preferably about 45 to 140, relative to 100 of the stock solution is suitable.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples unless the gist thereof is exceeded.

In addition, hereinafter, simply "parts" means "parts by weight".

(Example) 7 parts of ultrafine pulverized graphite powder having a maximum particle size of 8 μm was added to 89 parts of a dispersion medium formed by mixing 14 parts of isopropyl alcohol and 75 parts of 1,1,1-trichloroethane, and further acrylic resin (reaction Chemical industry "Plus size CB-2" 3 parts and alkylphenol type phosphoric acid ester (Toho Chemical Industry "Gafa
c RE-610 ") was added and stirred to thoroughly disperse the graphite powder to obtain a stock solution.

100 parts of the stock solution was enclosed in a spray can together with 70 parts of dimethyl ether to obtain a composition for aerosol.

Table 2 shows various properties of the aerosol composition. The evaluation method of the characteristic is as follows.

Dispersible spray the composition for aerosol from a spray can to a glass plate,
The presence or absence and presence or absence of aggregates of the lubricating powder in the formed coating film were observed.

Sprayability Spray the composition for aerosol from a spray can onto a glass plate,
The force of spray and the presence or absence of clogging of the injection port were observed.

Drying composition for aerosol is sprayed from a spray can onto a glass plate,
The time required for the formed coating film to dry was measured.

Uniformity of coating film Spray the composition for aerosol from a spray can onto a glass plate,
In addition to observing coating unevenness of the coating film formed, homogeneity was evaluated using a crush gauge consisting of a stainless steel flat plate and a square bar.

Adhesion of coating film Spray the composition for aerosol from a spray can to a glass plate,
After drying, the formed coating film was peeled off by hand to check the degree of adhesion strength.

Storage stability At room temperature or with the aerosol composition enclosed in a spray can.
After storage for 1 month, 3 months or 6 months at each temperature of 45 ° C., the storage stability was comprehensively evaluated from the above-mentioned test results of dispersibility and jettability and the presence or absence of corrosion of the can.

(Comparative Examples 1 and 2) An aerosol composition was produced in exactly the same manner as in the above Examples except that the raw materials used and the amounts thereof were changed as shown in Table 1, and the characteristics thereof were exactly the same as in the above Examples. The evaluation results are shown in Table 2.

(Comparative Example 3) Graphite powder having a maximum particle size of about 10 μm, Freon 113 and Freon 12
Table 2 shows the results of evaluation of a commercially available aerosol-containing composition containing the same as in the above Examples.

(Effects) The composition for aerosol of the present invention has a dispersibility in a dispersion medium of a lubricating powder, a jetting property at the time of spraying, a drying speed of a coating film formed by spraying, although it does not contain any CFCs. And a composition for an aerosol in which various performances required for spraying of a lubricating powder such as homogeneity of the coating film, adhesion of the lubricating powder to a coated surface, and storage stability are obtained by using a conventional CFC. The above is the same as, and provides a great industrial benefit.

Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display area // (C10M 169/04 103: 02 Z 105: 04 105: 18 105: 12 137: 04 105: 52) C10N 40:24 A 40:36 50:04 50:08

Claims (1)

[Claims] 1. A composition for aerosol containing a dispersion medium, a lubricating powder, a propellant and an additive, which contains isopropyl alcohol and 1,1,1-trichloroethane as the dispersion medium and dimethyl ether and / or as a propellant. An aerosol composition comprising LPG and an anionic surfactant as the additive.