JPS5819349B2 - Application roller for partial thickening coating - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an applicator roller for partial thickness coating, and more specifically, the present invention relates to a coating roller for partial thickness coating, and more specifically, for coating a sheet of metal, plastic, etc., film, or foil with a normal thickness and a partial thickness coating. The present invention relates to a coating roller for simultaneously applying a layered coating film by one roller coating.

A coated structure having a partially thickened coating film is particularly desired in fields where a portion of the coated structure is particularly required to have scratch resistance, corrosion resistance, and durability to prevent metal elution.

For example, in the field of iron making, a painted metal material is cut to a certain size as desired, then formed into a cylindrical shape, and the opposing edges of the material are joined by soldering, welding, or metal adhesive. At the same time, both opening edges of the cylindrical body to be formed are bent outward to form a flange, and the flange of the cylindrical body and the can lid (top and bottom lid) are tightened to form the final product. do.

According to the research conducted by the present inventors, the flange part is the most likely to cause metal elution and the most likely to be corroded by the contents of the painted iron. The cause is that the paint film is scratched due to severe processing such as machining and double seaming, and also due to high-speed contact with processing tools, transportation tools, can lids, etc. during the iron making process. Conceivable.

Thus, in the case of such painted metal materials for iron making, if a thick coating of protective paint is applied to the part of the material that will become the flange in advance, it is highly effective in preventing metal elution and improving corrosion resistance. is played.

When performing such partial thickening coating, it is conceivable to paint the entire surface of the metal material to a constant thickness and uniformly, and then apply a second coat only to the thickened areas, but in this case, A two-stage painting operation and a subsequent two-stage baking operation are required, which is unfavorable both in terms of the number of steps and in terms of thermal economy.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an applicator roller for partially thickened coating, which is capable of manufacturing a painted structure having a normal thickness coating film and a partially thickened coating film in a single coating operation. .

Another object of the present invention is to provide a relatively thin coating film with a normal thickness;
For partial thickness coating, which allows relatively thick partial thickness coating to be applied with a single roller application without problems such as paint scattering (misting), inclusion of air bubbles, or uneven thickness. To provide a coating roller.

According to the present invention, in a paint applicator roller having an axis and a circumferential surface for holding paint, the applicator roller surface has a normal thickness and a smooth circumferential surface. and a working surface for thick application consisting of an arch-shaped notch, and more preferably, the arch-shaped notch has a ratio (h/l) of cut depth h)/cut length 1). 0.005 to 0.05, and the surface of the notch has an Hmax of 0.03 mm or more and a pitch of 1.
A coating roller for partial thickening coating is provided, which is characterized by forming a rough surface or an uneven surface of 5 mm or less.

The present invention will be explained in detail below based on specific examples shown in the accompanying drawings.

In FIG. 1 showing an applicator roller of the present invention, this applicator roller consists of a shaft center 1 made of metal, for example, and a circumferential surface 2 for holding the paint to be applied. 2 has a working surface 3 for coating with a normal thickness consisting of a smooth circumferential surface and a working surface 4 for thick coating consisting of a notch.

In Figures 2-A and 2-B for explaining the roller coating process, the paint 11 in the pan (paint reservoir) 10 is applied via a fountain roller 12 and a distribution roller 13. The coating is applied to the surface of a substrate 15 to be coated, such as a metal substrate for iron making, which is supplied to the surface of the coating roller 14 at a constant speed to the circumferential speed of the coating roller 14 .

A paint reservoir 16 is formed on the flow stop side of the contact position (closest position) between the substrate 15 and the application roller 14, and the clearance between the substrate 15 and the application roller 14 at this closest position is defined as Dp. At this time, a paint layer 17 having a thickness of approximately Dp/2 will be formed on the soil of the substrate 15.

In the roller coating process using the roller of the present invention, the coating operation with the smooth circumferential surface, ie the coating working surface 3 of normal thickness, is carried out according to the above principles explained in connection with FIG. 2-A.

The application roller 14 of the present invention is as shown in FIG.

It has an arch-shaped cutout 4, that is, a working surface 4 for thick coating, corresponding to the thick coating of the target painted structure, and partially thick coating according to the principle explained below with respect to Fig. 2-B. will be held.

That is, this cutout portion 4 holds a relatively large amount of paint itself compared to the other peripheral surface portion 3 and comes into contact with the substrate 15 to be coated, and also transfers the paint from the liquid reservoir 16 to the substrate 15 to be coated.
The effect is to apply a larger amount.

Now, if the dimension of the partially thickened coating part is LF, and the gap cross-sectional area of the notch 4 is SF, then the notch 4 of the application roller 14
, approximately, where K is a coefficient depending on the notch shape, paint viscosity, and coating condition that varies between 2 and 20.
8 will be applied.

Thus, when the application roller 14 of the present invention is used, it is possible to apply a uniform coating 17 to the substrate 15 to be coated, and to selectively form a thick coating 18 of paint on the required areas. will be understood.

In the present invention, the shape and dimensions of this arch-shaped notch 4 are determined by the ratio (h) of cutting depth (h)/cutting length (1).
/l) is in the range of 0.005 to 0.05, and the surface may form a rough or uneven surface with Hmax of 0.03 mm or more and pitch of 1.57rLrIL or less, It is particularly desirable to provide the above-mentioned partially thickened coating film without problems such as misting of the paint, entrapment of air bubbles, and uneven thickness.

In FIG. 3-A showing an enlarged view of the arch-shaped notch 4 of a preferred example (A1) of the application roller of the present invention, the cut depth h in this specification refers to the depth h of the arch-shaped notch 4. The cut length 1 means the length of the chord of this arched cutout 4.

This notched surface 5 forms a rough surface or an uneven surface, and its maximum height (roughness Hmax) is 0.03 mm or more, particularly 0.05 mm or more, and its pitch (P) is 1. 57rtrIL or less, especially LOmm or less.

Therefore, the importance of providing the arch-shaped notch 4 and keeping each of the above-mentioned dimensions within the above-mentioned ranges will become clear by referring to Table 1, which will be described later.

That is, this Table 1 describes the application of partial thickening of tin-free steel substrates with epoxy-phenolic resin paints using applicator rollers of various shapes and sizes as shown in Figures 3-A to 3-E. The results of the painting are recorded.

In Table 1, Ll, L2. L3 and L4 are the thickness of the coating film at the four boundary lines of the partially thickened painted area divided into five equal parts.

-d Thick build-up ratio (L) --X 100 In the formula, D represents the thickness of the thick build-up coating film at the above-mentioned portion,
d represents the thickness of the flat thin coating film at a position 2 CrrL away from the edge of the thick coating film, and is expressed as follows.

Also, max, min and average. A total of 10 maximum values, minimum values, and average values are shown for each of the 5 samples.

As shown in Fig. 3-C, with the application roller (A3) provided with groove-like notches without providing arch-like notches 4, the unevenness of the thick coating film is significant, and misting and air bubbles are also caused. However, according to the present invention, application rollers 116.1 (Fig. 3-A), A, 2 (Fig. 3-A), A, 2 (Fig. B
In the cases shown in Fig.) and A5 (Fig. 3-E), the above-mentioned coating film defects can be improved while significantly reducing the variation in film thickness.

In particular, when the thickness of the epoxy-phenol resin paint film is uneven and the film thickness becomes abnormally large, an uneven pattern is formed on one surface due to convection of the paint during baking (called crawling). However, according to the present invention, it can be seen that such drawbacks are also significantly improved.

Further, according to a preferred embodiment of the present invention, when various dimensions such as h/l, Hmax, and P are set within the ranges defined by the present invention, it is possible to apply thick coating with a more uniform coating thickness, and to eliminate coating defects more completely. In particular, high-speed painting work becomes possible.

In the present invention, the shape of the notch part of the application roller can be changed in many ways without departing from the spirit of the present invention. For example, instead of making the shape of the chord part flat, it can be changed to a quadratic curve shape, for example, an inverted shape. It can be formed into various shapes such as an arcuate shape, a wave shape, or an inverted trapezoid shape.

As the application roller, one having a synthetic rubber surface is suitable, and butyl rubber-based and ethylene-propylene rubber-based ones are most suitable.

An applicator roller having such a structure can be manufactured by grinding nine rollers or by casting using a specific mold.

[Brief explanation of the drawing]

FIG. 1 is a perspective view schematically showing the application roller of the present invention, and FIG.
Figure -A is the principle of roller coating, Figure 2-B is an explanatory diagram showing the thickness of partial thickening coating using an arched notch roller, Figure 3-A, Figure 3-B, and Figure 3-C. , 3-D and 3-E are enlarged cross-sectional views showing the arch-shaped cutouts of the various rollers (A1 to A5) shown in Table 1, in which 1 is a shaft;
2 is a circumferential surface, 3 is a working surface for normal painting, and 4 is a working surface for thick coating consisting of an arch-shaped notch.

Claims (1)

[Scope of Claims] 1. A paint applicator roller having an axis and a circumferential surface for holding the paint to be applied, wherein the applicator roller surface has a smooth circumferential surface and has a normal thickness. A coating roller for partial thick coating, characterized in that it has a coating work surface and a thick coating work surface consisting of an arch-shaped notch. 2 The arch-shaped notch has a cutting depth h)/cutting length l) ratio (h/l) of 0.005 to 0.050.
:), and the surface of the cutout portion forms a rough or uneven surface with an Hmax of 0.03 mm or more and a pitch of 1.5 mm or less. The application roller described in item 1.