JPS6331265B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus that is incorporated into the process of molding or manufacturing synthetic resin or metal veneers or plywood, and which applies a primer to the surface of a traveling elongated plate.

In order to improve the appearance, corrosion resistance, coating adhesion, etc. of the surface of a plate-shaped body, it is known to coat it with various primers. This method (1) eliminates the need for a powerful water washing process and allows the equipment to be made more compact. (2)
Does not cause wastewater pollution. (3) When applying a top coat, the range of paints that can be used expands. (Four)
It has advantages such as high rust prevention effect and is widely used. In addition, the conventional surface treatment using this method is
This is carried out in a separate process from the above-mentioned plate-shaped body forming or manufacturing process, and there is no known method that is incorporated into or connected to the above-mentioned process to enable consistent continuous processing.

In the present invention, a primer application device is incorporated into the process of molding or manufacturing synthetic resin or metal veneers or plywood, and is connected to the process so that consistent continuous processing can be performed. Alternatively, many manufacturing plants are not usually explosion-proof facilities, and it is desirable to avoid using organic solvents as primers. Therefore, a water-based primer such as an aqueous solution or aqueous dispersion is used. However, if these primers are applied directly to a hot plate, extreme film thickness unevenness may occur due to gelation of the primer, or the primer may Due to poor compatibility between the plate-shaped bodies, uneven film thickness may occur.

The present invention was made to solve this problem, and includes a water-washing zone prior to the zone where the water-based primer liquid is applied, and both zones are separated by a roller that rolls in contact with a plate-like body. The plate should not come into contact with the uncooled plate or be diluted by cooling water, and the plate should be cooled in the washing zone and sent wet to the next primer coating zone. It is made to be easily compatible with aqueous primer liquid. That is, the present invention consists of a washing zone A, a primer coat zone B where an aqueous type primer liquid is applied, and a drying zone, and of each zone A, B, and C, at least between the washing zone A and the primer coat zone B. A roller 3 that rolls in contact with the plate-shaped body 2 separates both zones A and B, and the hot and dry plate-shaped body 2 is first washed with water in the washing zone A, cooled, and its surface is wetted with water. A running elongated plate characterized in that it is incorporated in a process of forming or manufacturing a elongated plate-like body, in which a water-based primer liquid is applied in a subsequent primer coat zone B, and then dried in a drying zone C. The present invention relates to an apparatus for applying a primer to the surface of a shaped body.

The long plate-shaped articles to which the present invention is applied include various metals such as aluminum, iron, copper, and zinc, alloys containing these metals as main components, and synthetic resins such as polyethylene, polypropylene, polyvinyl chloride, and polyethylene terephthalate. There are veneers and plywood in any shape, such as plate-like strips or coils, made of aluminum. This also applies to three-layer laminates that serve as the outer layer.

The water-based primer used in the present invention includes various primer liquids in the form of an aqueous solution or water dispersion, and is usually a composition in which a film-forming polymer and metal ions are dissolved or dispersed in water. be.

Most commonly used organic polymers can be used as film-forming polymers, including vinyl acetate, vinylidene chloride, their copolymers, acrylic acid, methacrylic acid, acrylic esters, and hydroxyl. Acrylics such as acrylic acid and hydroxymethyl methacrylic acid, and their copolymers, alkyds, epoxys, fluorine-based, urethane-based, polyester-based, styrene-based,
It is one type or a mixture of two or more types of water-soluble or water-dispersible resins and rubbers such as synthetic rubbers such as olefins and their copolymers butadiene, and natural polymers. The proportion of the polymer in the primer liquid is preferably 0.1 to 60% by weight in terms of solid content, depending on the type, viscosity, and thickness of the film formed, from the viewpoint of work efficiency.

Metal ions include titanium ions, zirconium ions, iron ions, etc., and sources of these metal ions include K ₂ TiF ₆ , (NH ₄ ) ₂ TiF ₆ , TiF ₆ ,
Titanium compounds such as TiO ₃ O ₄ , Ti(SO ₄ ) ₂ , Ti(OH) ₄
Li ₂ ZrF ₆ , No ₂ ZrF ₆ , H ₂ ZrF ₆ , (NH ₄ ) ₂ ZrF ₆ ,
ZrOsO ₄ , Zr(SO ₄ ) ₂ , zirconium compounds such as zirconium acetate FeSO ₄ , Fe ₂ (SO ₄ ) ₃ , FeCl ₂ ,
_FeCl3 , Fe(OH) ₂ , Fe(OH) ₃ , _FeF2 , _FeF3 , Fe
( _NO3 ) ₂ , Fe( _NO3 ) ₃ , _FeCO3 , FeS, _FS2 , FeO,
There are iron compounds such as Fe ₂ O ₃ and iron organic chelate compounds, and one or more of them may be used as necessary. The concentration of these metal source compounds in the primer solution is 0.1 to 10 g/in terms of titanium zirconium or iron, especially 0.3 to 3 g/
Preferable in terms of coating film performance.

It is desirable to further add the following additives to the primer liquid in order to further improve its coating film adhesion, corrosion resistance, etc.

That is, other additives include tannins or tannic acid, which may include partially decomposed hydrolyzable tannins or condensed tannins, such as depside, Chinese tannic acid,
Examples include hamamelitannic acid, maple tannic acid, chebulic acid, sumac tannin fivefold tannin, ellagate tannin, catechin, catechin tannic acid, kepratiyotannic acid, etc.
It is usually added to the primer liquid in a range of 0.1 to 20% by weight. If the amount added is less than 0.1% by weight, the effect of forming a passivation film is small and it is not practical;
The solubility of tannins or tannic acid exceeds
It is disadvantageous in terms of workability and economy.

Other preferred additives include 2 to 6 linked phosphate esters of myo-inositol and water-soluble salts in which one or more of the hydroxyl groups is substituted with an alkali metal or alkaline earth metal; For example, myo-inositol diphosphate, myo-inositol triphosphate, myo-inositol tetraphosphate, myo-inositol pentaphosphate, etc. Furthermore, the hydroxyl group of these bonded phosphate esters may be Na, K, Li, Mg,
Water-soluble salts substituted with metals such as Ca, Sr, and Ba. Myo-inositol hexaphosphate ester is commonly known as phytic acid, and since the other phosphoric esters mentioned above are mainly obtained by hydrolyzing phytic acid, phytic acid is industrially the most useful. The concentration of compounds obtained from phytic acid, including these phytic acids, in the primer solution is preferably 0.1 to 10 g/particularly 0.3 to 3 g/. If the amount is less than 0.1 g/l, the effect of improving corrosion resistance and film adhesion cannot be obtained. Even if it exceeds 10g/, the performance will not change, but it will impair economic efficiency.

The primer solution used in the present invention contains inorganic acids and their salts such as phosphoric acid, nitric acid, hydrofluoric acid, hydrochloric acid, boric acid, oxalic acid, citric acid, malic acid, etc., as necessary to adjust the pH. , organic acids such as maleic acid, phthalic acid, lactic acid, tartaric acid, chloroacetic acid, acrylic acid, methacrylic acid and their salts; alkaline substances such as caustic soda, caustic potash, alkali salts, ammonia, ethylamine,
Amines such as diethylamine, triethylamine, and ethanolamine can be added, and other coloring agents and the like can also be added.

Next, the present invention will be explained in more detail based on the accompanying drawings.

FIG. 1 is a schematic diagram showing a primer coating apparatus of the present invention. This equipment can be used in conjunction with a line of forming equipment for various plate-shaped objects.In other words, a line that forms laminates in which aluminum foil is crimped onto both outsides of thermoplastic resin with or without adhesive. In order to incorporate the thermoplastic resin into a plate, a pressure roll is installed downstream of an extruder that melts and extrudes the thermoplastic resin into a plate shape, and a pressure roll is installed to press the thermoplastic resin plate and the aluminum foil, and the primer application device of the present invention is installed downstream of the extruder. If provided, the primer-coated laminates can be continuously obtained in a continuous line in a long shape.

Primer coating on the plate-shaped body is performed on one or both sides of the outer surface, and the case where it is applied on both sides will be described below.

The primer coating device consists of a water cooling zone A, a primer coating zone B, and a drying zone C as shown in the figure. Of these, water cooling zone A and primer coat zone B are in the same casing 1.
It is desirable to make it more compact by arranging it inside.

Each zone will be explained in turn below.

In the water cooling zone A, a pair of water stopper rolls 3, 3, which sandwich the plate-like body 2 from above and below, are installed at appropriate intervals along the running line of the plate-like body.
Showers 4, 4 are arranged vertically between the rolls 3, 3, and the water is sprayed in the form of a spray.
It may be in the form of water droplets or any other form. The cooling water supplied to the plate-shaped body is horizontally stopped by the roll, and after dripping from the plate-shaped body 2, it is poured into the casing 1.
It is discharged to the outside from the drain port 5 at the bottom. Here, since the primer liquid has a tendency to rapidly gel from around 50°C, the plate-like body is cooled to about 40°C and completely wetted with water. After passing through the water cooling zone A, the plate-shaped body 2 is sent to the primer coat zone 2 with its surface uniformly wet.

Primer coat zone B is the roll 3, 3 above.
Similarly, a pair of squeezing rolls 7, 7 that sandwich the plate-shaped body from above and below are supported on the casing 1, and the primer liquid sent from the primer tank 8 through the pump 9 is transferred onto the upper squeezing roll 7 on the plate-shaped body 2. A spray 11 is installed below the plate to directly spray the bottom surface of the plate, and the primer is coated using a method similar to a roll coater. In order to avoid bridging (adhesion) of the primer at both ends of the plate-shaped body, it is preferable to provide the primers at an eccentric amount δ in the horizontal direction. The amount of primer liquid supplied to the upper roll 7 may be smaller than the amount sprayed to the lower surface of the laminate, but up to the weir by the cloth 12 provided in front of the roll 7,
Alternatively, if the cloth 12 is not provided, it is desirable to create a pool of liquid up to the water stopper roll 3 and to keep the amount of overcrow from the side edge as small as possible. In order to prevent unevenness in film thickness caused by this, it is preferable to provide a wet cloth 13 that reaches the upper squeezing roll 7. Primer liquid overcrowded from the above side edge and spray 1
The surplus of the primer liquid sprayed onto the lower surface of the laminate in step 1 is collected in a liquid receiving part 15 and then returned to the primer tank 8. After the squeezing roll 7, a nozzle 16 is installed to suck up the liquid accumulated on the side edge of the plate. The intake air is preferably separated by a cyclone 17 and then recycled into the casing 1. This keeps the relative humidity inside the casing saturated and the primer roll 7
Helps prevent local dryness on the skin. Reference numeral 18 is an exhaust hole provided at the top of the casing.The primer liquid supplied onto the plate is squeezed by a squeezing roll 7, forms a uniform primer layer on the plate, and then passes through the drying zone. It is sent to C and dried. It was confirmed that the corrosion resistance of the primer formed on the plate-shaped body improved as the film thickness increased. The film thickness can be increased or decreased by changing the concentration of the primer solution. The film thickness is usually 0.01μ or more, preferably about 0.05μ to 10μ.

In the drying zone C, an infrared heater 21 is provided in the casing 20, and the air sucked in by the blower 22 is heated by the heater 21 and then blown onto the plate-shaped body,
Consisting of a dryer that discharges water through a drainage hole 23,
Dry the wet primer on the plate. If the surface condition of the plate is poor, there may be areas with a large amount of primer liquid, which may not be completely dried. In that case, it adheres to the take-up roll (not shown) and causes contamination of the surface of the plate during the night. As a countermeasure against this problem, in addition to providing a dryer with a sufficient drying capacity, it is preferable to provide a nozzle 25 in front of the take-up roll for blowing out air when necessary. Since the above phenomenon occurs only on the upper surface of the laminate, the nozzle 25 may be installed only on the upper surface of the laminate.

As described above, the present invention relates to an apparatus that is connected to the process of forming or manufacturing a long plate-like body and applies a primer liquid to the surface of a running long plate-like body, in which a water-based primer liquid is applied to the washing zone A. It consists of a primer coat zone B for coating and a drying zone C, and among each zone A, B, and C, a roller 3 that rolls in contact with the plate-shaped body 2 is arranged between at least the washing zone A and the primer coat zone B. The hot and dry plate-like material 2 is first washed with water in washing zone A, cooled down, and its surface is wetted with water and then dried in the next primer coating zone B. I made it to
It is possible to perform consistent continuous processing by being connected to the molding or manufacturing process, it is possible to make the plant non-explosion-proof by using a water-based primer liquid, and it is easy to handle and store. A roller placed between the primer coat zone and the primer coating zone separates the two zones and drains the water, preventing the primer liquid from coming into contact with an uncooled plate or being diluted by cooling water, and making it possible to apply the primer liquid. It is possible to cool down the dried high-temperature plate-like body by washing with water prior to the process, and also to make the plate-like body surface wet with water so that it is easily adapted to the primer liquid.
The roller has the functions of separating and draining both zones, cooling with water, and keeping the plate surface wet in the primer coat zone, which simplifies the structure of the device compared to performing each function separately. It has the following effects:

[Brief explanation of the drawing]

The figure is a schematic diagram of a primer coating device according to the present invention. 1... Casing, 2... Plate body, 3... Water stop roll, 4... Shower, 7... Squeezing roll,
10...Nozzle, 11...Spray, 20...Casing, 21...Infrared heater, 22...Blower.

Claims (1)

[Scope of Claims] 1. In an apparatus that is connected to the process of forming or manufacturing a long plate-like body and applies a primer liquid to the surface of a running long plate-like body, a water-washing zone A applies a water-based primer liquid. It consists of a primer coat zone B and a drying zone C, and of each zone A, B, and C, a roller 3 that rolls in contact with the plate-shaped body 2 is arranged between at least the washing zone A and the primer coat zone B. Both zones A and B
The high temperature and dry plate-shaped body 2 is separated into
It is characterized in that it is first washed with water in washing zone A and cooled, the surface is wetted with water, then a water-based primer liquid is applied in primer coat zone B, and then it is dried in drying zone C. Primer coating equipment. 2. The primer coating device according to claim 1, wherein the water used in the washing zone A is purified water. 3. The primer coat zone B is provided with primer liquid supply devices 10 and 11 disposed on at least one side of the plate-like body 2, and a pair of squeezing rolls 7 that sandwich the plate-like body 2 from both sides. The primer coating device according to scope 1. 4 The supply device includes a wet cloth 1 that reaches the squeezing roll 7.
3. The primer coating device according to claim 3, further comprising: 3. 5. The primer coating device according to claim 3, wherein the pair of squeezing rolls 7 are eccentric in the traveling direction of the plate-like body.