JPH07328523A - Method for forming putty coating-film on outer sheet of railroad vehicle - Google Patents

Abstract

PURPOSE:To form a putty coating-film with a thick thickness on the surface of an outer sheet by a simple operation by a method wherein a curing agent component and a compressed air are homogeneously mixed by means of a static mixer provided inside of a spray gun and the obtd. homogeneous mixture is ejected while it and the main agent component are jointed and mixed to perform spray coating. CONSTITUTION:A compressed air and a curing agent component are homogeneously mixed by providing a static mixer 6 in a sprag gun 3 and the obtd. homogeneously mixture is ejected while it is jointed and mixed with a main agent component preheated at 30-50 deg.C and transferred under a pressure being suitable for spray coating at the apex of the spray gun 3 to perform spray coating. As this result, a homogeneous putty coating film is formed. Namely, more homogeneous mixing can be done in the case wherein the homogeneous mixture of compressed air and the curing agent component is brought into contact with and mixed with the main agent component for mixing than in the case wherein the curing agent component alone is brought into contact with and mixed with the main agent component. In addition, compressed air is also useful for support for spray pressure of an air spray.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a putty coating film on the surface of a railroad vehicle outer plate having excellent coating workability.

[0002]

2. Description of the Related Art The surface of a railroad car skin is usually coated with a primer in order to give it a beautiful appearance and to prevent corrosion, and then putty (putty) is applied to smooth the surface. However, it is finished by top coating.

By the way, the primer coating, the surfacer coating and the top coating are usually carried out by using a spray coating method.
Since it is necessary to make a thick film of about 10 mm, it is putty with a metal spatula.

[0004]

However, a railroad vehicle has a very large outer skin surface area as compared with a road vehicle, and in addition, in order to correct the strain (waviness) of the outer skin of the railcar to smooth it. Usually, about 3 to 6 times, putty work by manpower is required. Therefore, the method of putting on putty with a spatula not only takes a lot of work time, but also requires skill and there is a problem that workability is very poor. It was

The present invention solves the above-mentioned problems of the prior art. A thick putty coating film is formed on the outer surface of a railroad vehicle in a short time and with a simple operation without requiring skill. The purpose is to provide a method of doing.

[0006]

[Means for Solving the Problems] That is, according to the present invention, a main component containing an unsaturated polyester resin, a vinyl monomer and a filler as essential components, an organic peroxide curing agent and a plasticizer are provided on the outer surface of a railroad vehicle. In a method of forming a putty coating film by spray-coating a solventless putty composition comprising a curing agent component having an agent as an essential component, it was preheated to 30 to 50 ° C. and pressure-fed at a pressure suitable for spray coating. The main agent component, the curing agent component and the compressed air fed by compressed air are separately introduced into a spray gun, and the curing agent component and the compressed air are homogeneously mixed by a static mixer provided inside the spray gun. Characterized in that the obtained homogeneous mixture is discharged and spray-coated while being mixed and mixed with the main component at the tip of the spray gun. It relates a method of forming the Te coating.

The present invention is described in detail below: The putty composition used in the present invention is a solventless two-part putty composition comprising a main component and a curing agent component. The main component is composed of unsaturated polyester resin, vinyl monomer and filler as essential components, and if necessary, various additives such as curing accelerator, stabilizer, etc., modified resin, plasticizer and the like. It

As the unsaturated polyester resin, an unsaturated polyester resin used in a usual putty composition can be used. In the present invention, (a) α, β is particularly preferable as the unsaturated polyester resin. A polybasic acid component 30 consisting of a mixture of unsaturated polybasic acids and saturated polybasic acids in a molar ratio of 9: 1 to 3: 7, preferably 8: 2 to 4: 6.
〜60% by weight, and (b) polyhydric alcohol component 10-40
An acid value of 70 or less and a number average molecular weight of 10 obtained by reacting 3% to 30% by weight of (c) an allyl compound having an iodine value of 40 or more and / or an animal or vegetable oil with 3 to 30% by weight.
When an unsaturated polyester resin of 00 to 4000 is used,
It is preferable because a putty coating film having excellent dryness, less likely to cause cracks, and excellent in polishing property can be obtained.

Examples of α, β-unsaturated polybasic acids include maleic acid, maleic anhydride, fumaric acid, itaconic acid and citraconic acid. As the saturated polybasic acid, there are adipic acid, azelaic acid, sebacic acid, phthalic anhydride, phthalic acid, isophthalic acid, tetrahydrophthalic anhydride, etc. It is preferable to mainly use a system. In the polybasic acid component, when the molar ratio of the α, β-unsaturated polybasic acid and the saturated polybasic acid is out of the above range, the dryness, polishing property, crack resistance, etc. of the putty coating film may be reduced. Since either of them may be insufficient, it is preferable to set the value within the above range.

Examples of the polyhydric alcohol component include ethylene glycol, propylene glycol, diethylene glycol, water-added bisphenol A, and ethylene oxide or propylene oxide derivatives of bisphenol A.

The air-drying component is used for improving the polishing property of the putty coating film, and for that purpose, the air-drying component is preferably an allyl compound having an iodine value of 40 or more and / or animal or vegetable oil. Examples include allyl compounds such as allyl glycidyl ether, allyl glycol, glycerin (di or mono) allyl ether and trimethylolpropane diallyl ether; soybean oil, linseed oil, dehydrated castor oil, tung oil, fish oil or transesterified oils thereof. , And animal and vegetable oils such as fatty acids.

In addition to the above-mentioned components, components such as alkyl glucidyl ester and dicyclopentadiene may be used as a reaction component in the unsaturated polyester resin component in order to improve durability and adhesion of the putty coating film against expansion and contraction. It is possible.

In the unsaturated polyester resin used in the present invention, the relative amounts of the polybasic acid component, the polyhydric alcohol component and the air-drying component are not strictly limited, but based on their total weight. 30-60 each
Appropriately, wt%, 10-40 wt% and 3-30 wt%.

Such an unsaturated polyester resin is produced by a conventional method, for example, a polycondensation reaction of a polybasic acid component, a polyhydric alcohol component and an air-drying component at 150 to 250 ° C., or all of the polybasic acid component is carried out. Or, after reacting a part of the polyhydric alcohol component at 120 to 220 ° C, the remaining polybasic acid component and air-drying component are added, and 120 to 220 ° C is added.
It is obtained by reacting with. The unsaturated polyester resin having a number average molecular weight of 1,000 to 4,000 and an acid value of 70 or less is suitable from the viewpoint of workability and water resistance of the putty composition.

Examples of vinyl monomers include styrene, α-methylstyrene, chlorostyrene, vinyltoluene, t-butylstyrene, divinylbenzene, methyl (meth) acrylate, ethyl (meth) acrylate, glycidyl (meth) acrylate. , 2-ethylhexyl (meth) acrylate, vinyl acetate, acrylonitrile, diacryl phthalate and the like are mentioned as typical ones.

As the filler, extender pigments such as calcium carbonate, barium sulfate, talc, clay, kaolin, mica and silica, inorganic or organic color pigments such as titanium oxide, red iron oxide, carbon black, iron oxide and cyanine blue, Other typical examples include glass fibers, glass balloons, plastic balloons and the like.

As additives to be added as required, metal salt compounds of metals such as cobalt, manganese and calcium and organic acids such as naphthenic acid and octylic acid, hardening accelerators such as tertiary amines; hydroquinone Typical examples thereof include stabilizers and the like.

Examples of the modified resin include cellulose acetate butyrate and cyclopentadiene oil.

Regarding the blending ratio of each component in the main component, the weight ratio of unsaturated polyester resin to vinyl monomer is 30:70 to 80:20, preferably 45: 5.
It is preferably 5 to 65:35. Incidentally, if the former is less than the above range, the curability and the meat properties of the putty coating tend to deteriorate, while if it is more than the above range, the hardness of the putty coating will decrease, and scratches will occur during polishing. It tends to be easier.

The filler is 50 to 40 relative to 100 parts by weight of the mixture of unsaturated polyester resin and vinyl monomer.
0 parts by weight, preferably 100 to 250 parts by weight, the curing accelerator is 0 to 10 parts by weight, preferably 1 to 5 parts by weight, and the stabilizer is 0 to 10 parts by weight, preferably 1 to 5 parts by weight. Is appropriate.

On the other hand, the curing agent component is composed of an organic peroxide curing agent and a plasticizer as essential components, and if necessary, the additives and color pigments described above are added.

As the organic peroxide curing agent, methyl ethyl ketone peroxide, benzoin peroxide,
Representative examples include acetyl peroxide, cumene hydroperoxide, ditertiary butyl peroxide, cyclohexanone peroxide and the like.

As the plasticizer, phthalic acid esters such as phthalic acid dimethyl ester, phthalic acid diethyl ester and phthalic acid dioctyl ester; aliphatic dibasic acid esters such as adipic acid dioctyl ester and sebacic acid dibutyl ester; diethylene glycol diester Typical examples thereof include glycol esters such as benzoate.

The mixing ratio of the organic peroxide curing agent and the plasticizer is 3: 7 to 8: 2, preferably 5: 5 to 7: by weight.
A value of 3 is suitable.

The mixing ratio of the main component and the curing agent component is 100 in terms of the weight ratio of the total amount of the unsaturated polyester resin and the vinyl monomer in the main component component and the amount of the organic peroxide in the curing agent component. : 0.5 to 100: 5, preferably 1
It is suitable that the ratio is from 00: 1 to 100: 3.

Next, the method for forming a putty coating film on the surface of a rail vehicle skin of the present invention will be specifically described with reference to the drawings. FIG. 1 is a schematic configuration diagram of a coating means showing an embodiment of the present invention, and FIG. 2 is a side sectional view of a spray gun. Reference numeral 1 is a pressure tank for the main component, and reference numeral 2 is a pressure tank for the curing agent component. The main ingredient in the pressure tank 1 is sent to the airless coating machine 4 at a pressure of about 0.5 to 3 Kg / cm ² .

The airless coating machine 4 is provided with a heater 5 and has a viscosity of about 90 to 150 poise (Rion viscometer rotor so that the main component is heated to about 30 to 50 ° C. to enable spray coating. No. 2).

The main component component whose viscosity has been reduced is about 90 to 110K by the pump mechanism equipped in the airless coating machine 4.
It is supplied to the spray gun 3 at a pressure of g / cm ² . On the other hand, the curing agent component in the pressure tank 2 is sent to the spray gun 3 at a pressure of about 1 to 3 kg / cm ² . At the same time, compressed air is also supplied to the spray gun 3 at a pressure of about ^{2 to 4} kg / cm ² .

The curing agent component and compressed air supplied to the spray gun 3 are uniformly mixed by a static mixer 6 provided inside the spray gun 3. The homogeneous mixture of the hardener component and compressed air that was homogeneously mixed by the static mixer is mixed with the main component at the spray gun tip, that is, inside and outside the gun tip, and then mixed toward the outer surface of the railcar. Discharged to form a putty coating film on the outer surface of the railroad car skin. In the present invention, the static mixer 6 is provided in the spray gun 3 to uniformly mix the compressed air and the hardener component, so that the main component and the hardener component can be uniformly contact-mixed when airless spraying the main component. As a result, a uniform putty coating film is formed. That is, the case of contact-mixing a homogeneous mixture of compressed air and a curing agent component with the main agent component is more homogeneously mixed than the case of contact-mixing the curing agent component alone and the main agent component, and as a result, the main agent The components and hardener components are uniformly contact mixed. The compressed air also serves as a supplement to the spray pressure of the airless spray.

The putty composition consisting of the main component and the curing agent component is opened / closed by operating the trigger 7 of the spray gun 3 to supply / block the putty.

The putty coating is formed by spray painting the putty composition until the strain on the railroad vehicle body structure can be corrected, curing, and then optionally conventional paper / sander polishing.

[0032]

EXAMPLES The present invention will be described in more detail below with reference to examples. In the examples, "parts" and "%" are "parts by weight", respectively.
And "% by weight".

Example 1 A main component (viscosity 400 poise / 20 ° C.) having the following composition was prepared: unsaturated polyester resin varnish 33% styrene 8% titanium oxide 5% talc 52% hydroquinone 1% cobalt naphthenate 1% The unsaturated polyester resin varnish is a polybasic acid component consisting of maleic anhydride / adipic acid / phthalic anhydride = 50/30/20 (molar ratio), a polyhydric alcohol component consisting of diethylene glycol, and an empty space consisting of trimethylolpropane diallyl ether. Unsaturated polyester resin obtained by reacting with a dry component (acid value 10, number average molecular weight 180
It is a 65% styrene solution of 0, air-drying component ratio of 7.5%).

A hardener component having the following composition was prepared: methyl ethyl ketone peroxide 55% dimethyl phthalate 44% azo yellow pigment 1% two-pack epoxy resin primer coated steel plate (10
00 × 200 cm) with the coating means of the configuration diagram shown in FIG.
A solventless putty composition comprising the main component and the curing agent component was spray coated on the entire surface under the following spray coating conditions so that the average film thickness was about 3 mm. The coating was completed in a short time of 120 seconds. If you use putty with a spatula, 3
It took 0 minutes. Spray coating conditions: Mixing ratio of main agent component and curing agent component = 100: 3; Feeding pressure of main agent component from pressure tank to airless coating machine = 1 Kg / cm ² ; Temperature and viscosity of main agent component in airless coating machine = 40 ° C,
120 poise; pressure of the main component from the airless coating machine to the spray gun = 100 kg / cm ² ; pressure of the hardener component to the spray gun = 2 kg / cm
² ； Pressure pressure of compressed air to spray gun = 3.5Kg / c
m ² .

Examples 2 to 5 In order to evaluate the performance of the putty coating film obtained from the solventless putty composition used in Example 1, a putty coating film was formed under the same conditions as in Example 1, and Each test of the putty coating film for polishing property, heat cycle property, water adhesion resistance, tensile strength, and elongation was carried out. The test methods were as follows: Abrasiveness: After spray coating (thickness 3 mm) of a putty composition on a polished steel plate (150 × 70 × 0.8 mm) coated with a two-pack type epoxy resin primer, Leave at room temperature for 4 hours,
The water-resistant paper # 150 was used for manual polishing to evaluate the easiness of polishing (Example 2); Heat cycle property: After the putty composition was spray-coated (thickness: 3 mm) on the above-mentioned polished steel plate, at room temperature. It was left for 1 day, then put in a dryer at 80 ° C. for 2 hours, immediately put in a freezer at −10 ° C. for 2 hours, and this was repeated 4 times, and then the surface of the putty coating film was visually evaluated (Example 3); Water-resistant adhesion: After the putty composition was spray-coated (film thickness 1 mm) on the above-mentioned polished steel plate, it was left at room temperature for 1 day, and then 6
The dried test plate was immersed in warm water at 0 ° C. for 4 hours, bent at 90 degrees, and examined for peeling (Example 4). Tensile strength and elongation: A plastic plate was spray coated with the putty composition (film). After the thickness was 1 mm), the putty coating film was peeled off by standing at room temperature for 1 day. This putty coating film was cut into 10 × 50 mm, and the test piece was pulled at a pulling speed of 5 with a tensile tester.
The tensile strength and elongation were measured in mm / min (Example 5).

The results are shown in Table 1.
The putty coating film obtained had good coating workability as described in Example 1 and could be applied in a short time, and as shown in Table 1, the putty coating film had excellent performance.

[0037]

[Table 1]

[0038]

The method of forming a putty coating film on the surface of a railcar skin of the present invention is simple and requires no skill in any of new coating, repainting or repair coating of the railcar skin surface. It is possible to form a thick putty coating film by simple operation in a short time, and since the main component and the curing agent component are mixed at the tip of the spray gun, there is no problem such as pot life. Since a putty coating film is formed in a state of being homogeneously mixed, a uniform putty coating film excellent in original physical and chemical properties can be obtained.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a coating means showing an embodiment of the present invention.

FIG. 2 is a side sectional view of a spray gun.

[Explanation of symbols]

 1 Pressure tank for main component 2 Pressure tank for curing agent 3 Spray gun 4 Airless coating machine 5 Heater 6 Static mixer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takanari Suzuki 1382-12 Shimoishigami, Otawara-shi, Tochigi Dainippon Paint Co., Ltd. Nasu factory (72) Inventor Kazuo Tomizawa 1382-12 Shimoishigami, Otawara-shi, Tochigi Prefecture Dai Nippon (72) Inventor Takeshi Ishikawa 1382-12 Shimoishigami, Otawara-shi, Tochigi Dainippon Coating Co., Ltd. Nasu factory

Claims (3)

[Claims] 1. A main agent component having an unsaturated polyester resin, a vinyl monomer and a filler as essential components, and a curing agent component having an organic peroxide curing agent and a plasticizer as essential components, on the surface of a railroad vehicle outer plate. A method for forming a putty coating film by spray-coating a solventless putty composition comprising
The main ingredient component preheated to 50 ° C. and pressure-fed at a pressure suitable for spray coating, the hardener component pressure-fed by compressed air, and compressed air were separately introduced into the spray gun and provided inside the spray gun. Characterized in that the curing agent component and the compressed air are homogeneously mixed by a static mixer, and the resulting homogeneous mixture is discharged and spray-coated while being mixed and mixed with the main component at the tip of a spray gun. A method for forming a putty coating film on a vehicle outer plate. 2. The unsaturated polyester resin is (a) α,
Molar ratio of β-unsaturated polybasic acid to saturated polybasic acid 9: 1 to
30 to 60% by weight of polybasic acid component consisting of 3: 7 mixture
And (b) 10 to 40% by weight of a polyhydric alcohol component,
(C) Acid value 70 or less, number average molecular weight 1000 to 40 obtained by reacting with an air-drying component consisting of an allyl compound having an iodine value of 40 or more and / or animal or vegetable oil 3 to 30% by weight.
2. The method for forming a putty coating film on a rail vehicle outer plate according to claim 1, wherein the putty coating film is 00 unsaturated polyester resin. Wherein the main agent component, hardener component and respectively the compressed air ^{90~110Kg / cm 2, 1~3Kg / cm} 2
And a pressure of ^{2 to 4} Kg / cm ² are introduced into the spray gun, and the method for forming a putty coating film on the outer panel of a railway vehicle according to claim 1 or 2.