JPS5949917B2 - Printing method for objects with complex shapes - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrostatic screen printing method, in particular:
This paper relates to printing methods not only for flat surfaces but also for complex side surfaces having surfaces that are perpendicular to the flat surface or at angles close to the right angle.

Conventionally, most commonly known printing methods involve contact printing on a flat surface, such as lithographic printing, letterpress printing,
Intaglio printing methods, screen printing methods, etc. are known.

However, all of these printing methods are suitable for supplementing a plane, and are not suitable for printing on a cross section perpendicular to a plane or a surface having an angle close to a right angle. The so-called spray painting method, in which parts other than the printed part are masked and the paint is sprayed, is used to print right-angled cross sections, etc., but this method requires cleaning of the mask, etc., and is structurally complicated. However, it is not suitable for mass production.

The purpose of the present invention is to apply the above-mentioned known technology to form a uniform coating not only on flat surfaces but also on surfaces with complex shapes such as surfaces perpendicular to the flat surface or surfaces having an angle close to a right angle. The object of the present invention is to provide a printing method that eliminates the existing drawbacks.

In order to achieve the above-mentioned object, according to the present invention, a printing material having a complex-shaped surface such as a plane, a surface perpendicular to the plane, or a surface at an angle close to a right angle is placed on a metal plate, and the printing material is placed on a metal plate. A screen with openings is placed apart from the printed matter, a direct current voltage is applied between the metal plate and the screen, and powdered ink is placed on the screen in this state to charge it. In the electrostatic screen printing method in which the charged powder ink is splashed onto the printing material through the apertures of a screen, the screen apertures are the apertures facing the flat surface of the printed area of the printing material. and an aperture portion that is continuous with the aperture portion and has a size that corresponds at least to the surface area of the printing location on the side surface of the printing medium having a complicated shape.

Hereinafter, the present invention will be explained in detail using the accompanying drawings.

FIG. 1 is a diagram illustrating the principle of electrostatic screen printing used in the method of the present invention. 1 is metal/plate.

A printing material A is placed on a metal plate 1, a screen 2 is placed a few inches apart from the printing material A, and a DC voltage (several KV) is applied between the metal plate 1 and the screen 2. Furthermore, when the powder ink 3 is placed on the screen 2 in this state and the powder ink 3 is moved on the screen using the brush 4, the powder ink 3 is charged, and the charged powder ink 3 The powder ink flies onto the printing material A through the opening 5 of the screen 2 (the flying powder ink is 3'
Indicated by ) Print substrate A. In the present invention, the printing material has a shape as shown in FIG. 2, for example. This is represented as A in FIG. That is, the printing substrate N used in the present invention has a flat surface 11, a surface 12 perpendicular to the flat surface, or a surface 12 at an angle close to a right angle, and a complex side surface B in the shape of a locus, as shown in the second figure. FIG. 3 shows an example in which such printing material N is applied to the electrostatic screen printing method shown in FIG. 1, that is, a specific example according to the method of the present invention.

FIG. 3 is an explanatory diagram of a specific example for carrying out the method of the present invention. In FIG. 3, the shape of the aperture 5 of the screen 2 is adjusted to suit the surface of the printing medium N. That is, among the openings 5 of the screen 2, a portion 5a is adjusted to correspond to the plane 11 of the printing medium N, and therefore, this portion 5a corresponds to the plane 1.
It is used for printing one part, and the aperture part 5b is adjusted so that the aperture part 5b has a size corresponding to the surface area of the right-angled surface 12 of the printing substrate A'. 5b is used for printing on the right-angled surface 12. In this way, the present invention can reduce the flight force of charged powder ink due to electrostatic force even on the side surfaces of a printing substrate with a complicated shape, such as a surface with surface force, a surface perpendicular to a plane, or a surface with an angle close to a right angle. It is a printing method that is extremely useful in practice because it enables uniform printing.

[Brief explanation of drawings]

FIG. 1 shows an explanatory diagram for explaining the principle of the electrostatic screen printing method used in the method of the present invention, FIG. 2 shows a specific example of the printing substrate used in the method of the present invention, and FIG. 1 shows a specific explanatory diagram for carrying out the method of the present invention. 1...Metal plate, 2...Screen, 3
, 3t...Powder ink, 4...Brush,
5, 5a, 5b... Screen opening W) s1
1... Plane, 12... Surface perpendicular to the foreground,
13...Face with angle close to right angle, A, N...
・・Printing substrate, B・・・・・・A surface with a complex shape.

Claims (1)

[Claims] 1. A printing material having a complex-shaped surface such as a flat surface, a surface perpendicular to the plane, or a surface at an angle close to a right angle is placed on a metal plate, and a screen having an opening is placed at a gap from the printing material. Then, a DC voltage is applied between the metal plate and the screen, and in this state, powder ink is placed on the screen to charge it, and the charged powder ink is passed through the openings of the screen. In the electrostatic screen printing method in which the screen is splashed onto the printing material through the screen, the screen aperture includes an aperture portion that faces the flat surface of the printed area of the printing material, and a hole that is continuous with the aperture portion. ,
1. A printing method for a material having a side surface having a complicated shape, the method comprising: having an aperture portion of a size corresponding at least to the surface area of a printing location on the side surface of a printing material having a complicated shape.