TW201347618A - Three dimensional mask for printing - Google Patents

Abstract

A three dimensional mask for printing provides a substrate, and a printing surface and a PCB surface on both sides of the substrate, said mask has a plurality of patterned openings and a three dimensional structure, said three-dimensional structure includes a raised area on said printing surface and a recessed area on said PCB surface. Said mask has three-dimensional raised and recessed portions, the raised and recessed portions form angles with respect to the surfaces by predetermined angular degrees; the material of said mask material is pure nickel, which has high accuracy and uniformity, good quality surfaces, brightness, no rough spot, no scratch; the openings have good quality, smooth hole walls, no bur; said mask has low production cost and low power consumption, and no complex production technology is necessary.

Description

Three-dimensional mask for printing

The present invention relates to a mask, and more particularly to a three-dimensional mask for printing.

With the rapid development of China's electronics industry, mask printing technology has also been widely used in electronics manufacturing, SMT printing is typical. In order to solder electronic components and PCBs in the manufacturing process of electronic products, it is necessary to place tin on the PCB. There are hundreds of pads on the PCB that need to be tinned, and the positions of each pad correspond to electronic components. The best way to get the tin on the pad that needs to be soldered at once is to print. The method commonly used in the electronics industry is to make a piece of stainless steel with dense holes, each of which corresponds to a pad that needs to be tinned, and then the stainless steel piece is attached to the stretched mesh, and the mesh is attached to the mesh. Print on the underside of the mask frame.

Whether the solder paste of the pad is flat, uniform, and proper dosage will directly affect the effect of the electronic component SMT, especially when there are precision electronic component pads and hot pressing fingers, the printing mask is more demanding.

The printing mask is used to print solder paste molds. Currently, steel mesh is generally used. However, the precision of the steel mold made by the laser cutting technology cannot meet the requirements, and the quality of the layout is not high enough.

The development of the PCB industry is not limited to planar masks. The existing PCBs are developing rapidly. Some locations with specific requirements require concave parts, such as embedded bumps and printed boards to meet the soldering of larger components on the PCB. And does not affect the overall printing effect. The same is true for the convex part. Therefore, the future development trend of the metal mask system corresponding to the uneven shape on the PCB is produced.

Therefore, how to develop a new product that is superior to the printing mask made by ordinary steel mesh, and it is essential to have a precise aspect ratio and a good quality of the opening.

With the increasing availability of printed products, single-plane screen printing has not been able to meet the needs of the existing market. Nowadays, the market demand is increasingly pursuing individuality and fashion. The product has gradually developed from a single plane to a curved surface, high and low countertops, and is equipped with a hollow or raised design. In the field of high-precision manufacturing, even a small concave and convex portion of the surface of the substrate causes a large deviation in positional accuracy and dimensional accuracy during the transfer process and deformation of the mask, resulting in the scrapping of the product and the mask. When the two-dimensional mask is used for transfer, the mask opening at the edge of the surface of the surface of the substrate is accurately aligned due to inability to be in close contact with the substrate, resulting in a shift or misalignment of the transferred material. In the prior art, the printing method is often used for non-planar printing, but the printing method has problems such as small effective printing area and poor printing effect, especially for large-area printing products, and requires equipment investment. Large and costly. Therefore, the traditional printing method can not meet the requirements of today's screen printing for shaped products.

In order to realize the screen printing of special-shaped (stereo) products on existing equipment, the key lies in the production of screen printing boards, that is, the stencil making technology suitable for three-dimensional screen printing must be developed.

In view of the above, an object of the present invention is to provide a three-dimensional mask for printing which is superior in performance to a printing mask produced by a conventional steel mesh and which has a precise aspect ratio and a good opening quality.

To achieve the above and other objects, the present invention provides a three-dimensional mask for printing, comprising a substrate and a printing surface and a PCB surface on both sides of the substrate, the mask having a plurality of graphic openings and a three-dimensional structure. The three-dimensional structure includes a raised area on the printing surface and a recessed area on the PCB surface corresponding to the raised area.

In an embodiment of the present invention, the three-dimensional reticle for printing may have a graphic opening satisfying printing requirements, and the graphic opening on the three-dimensional structure includes an upper opening and a larger opening than the upper opening The lower opening has a taper of 3°~8°.

In an embodiment of the present invention, in the three-dimensional mask for printing, the angle between the recessed region of the mask and the surface of the PCB may be 80° to 90°.

In an embodiment of the present invention, in the three-dimensional mask for printing, the center of the raised area and the recessed area may be disposed on the same line, and the line is perpendicular to the surface of the mask; the recess The area is smaller than the area of the raised area, and the three-dimensional structure is a hollow structure.

In an embodiment of the invention, in the three-dimensional mask for printing described above, the hole wall of the three-dimensional structure is smooth.

In an embodiment of the present invention, in the three-dimensional mask for printing, the height of the raised region may be 0.1 mm to 10 mm.

In an embodiment of the present invention, in the three-dimensional mask for printing, the depth of the recessed region may be 0.1 mm to 10 mm.

In an embodiment of the present invention, in the three-dimensional mask for printing, the thickness of the mask may be 20 um to 100 um.

In an embodiment of the present invention, in the three-dimensional mask for printing, the material of the mask may be pure nickel.

In an embodiment of the present invention, in the three-dimensional mask for printing, the uniformity of COV of the pure nickel metal plating layer of the mask may be less than 5%; the surface brightness of the pure nickel metal plating layer The system can be one level of light.

Based on the above, the present invention provides a three-dimensional mask for printing, comprising a substrate and a printing surface and a PCB surface on both sides of the substrate, the mask having a plurality of graphic openings and a three-dimensional structure, wherein the three-dimensional structure comprises the printing The raised area of the face and the recessed area of the PCB face. The mask has three-dimensional three-dimensional convex and concave portions, and the convex and concave portions have an angle with a predetermined angle of the plate surface; the mask material is pure nickel, the precision is high; the uniformity is high, the plate The surface quality is good, bright, no roughness, scratches, pinholes; the opening quality is good, the hole wall is smooth, no burr; the mask version has low production cost, simple production technology and low energy consumption.

The above described features and advantages of the present invention will be more apparent from the following description.

The embodiments of the present invention are described below by way of specific embodiments, and those skilled in the art can readily appreciate the other advantages and functions of the present invention. The present invention may be embodied or applied in various other specific embodiments, and various modifications and changes may be made without departing from the spirit and scope of the invention.

It is to be understood that the structure, the proportions, the size, and the like of the present invention are only used in conjunction with the disclosure of the specification for the understanding and reading of those skilled in the art, and are not intended to limit the present invention. The qualifications of the implementation are not technically meaningful, and any modification of the structure, change of the proportional relationship or adjustment of the size shall remain in the presence of the effects and the objectives that can be achieved without affecting the invention. The technical content disclosed in the present invention can be covered. In the meantime, the terms "upper, lower", "one" and "bottom" are used in the description for convenience of description, and are not intended to limit the scope of the invention. Changes or adjustments are considered to be within the scope of the invention, without departing from the scope of the invention.

The embodiment of the invention provides a three-dimensional mask for printing, which is applied to the first step of printing the solder paste in the process of SMT surface mount technology, and the uniformity and opening of the mask surface during the printing of the solder paste The quality of the quality directly affects the quality of the tin, that is, the uniformity is good, there will be no phenomenon of poor tin under the thin surface of the board. Generally, the uniformity of the plating layer is improved by adding an anode baffle to the electroforming tank; if the opening quality is good, there will be no undesirable phenomenon such as tin, tin, and tipping. The biggest advantage of electroforming over laser steel mesh is that electroforming is atomic level deposition. As long as the development point is well controlled, the electroporated mask has a smooth hole wall and no burr.

Please refer to FIG. 1 , FIG. 2A , FIG. 2B and FIG. 3 . FIG. 1 is a schematic structural view of a three-dimensional mask for printing according to the present invention; FIG. 2A is a three-dimensional solid region of the three-dimensional mask for printing of the present invention. 2B is a schematic view showing the structure of the AA cross section of FIG. 2A; and FIG. 3 is a schematic view showing an embodiment of the three-dimensional mask for printing according to the present invention. As shown in the figure, the three-dimensional mask 1 for printing includes a substrate and a printing surface 11 and a PCB surface 12 on both sides of the substrate. The mask 1 has a plurality of graphic openings 10 and a three-dimensional structure. The structure includes a raised area 111 on the printing surface 11 and a recessed area 121 on the PCB surface 12 corresponding to the raised area 111.

In this embodiment, the angle between the recessed area 121 of the mask 1 and the PCB surface 12 may be 80° to 90°, for example, 80°, 85°, or 90°. The convex region 111 and the recessed region 121 of the mask 1 are close to a vertical angle with respect to the outside of the plate surface, thereby facilitating the precision of the solder paste under printing, which will be described in detail later.

In this embodiment, the raised area 111 is located on the same line as the center of the recessed area 121, and the line is perpendicular to the plane of the mask 1; the recessed area 121 is smaller than the area of the raised area 111, the three-dimensional The three-dimensional structure is a hollow structure, and the three-dimensional structure has a smooth hole wall and no burr.

In the embodiment, the hole wall of the plurality of pattern openings 10 in the mask plate 1 is smooth and has no burr, which can avoid the occurrence of defects such as collapse of tin, tin, and tip during solder paste printing.

In the embodiment, the height of the convex region 111 of the three-dimensional structure is 0.1 mm to 10 mm, and the depth of the concave region 121 of the three-dimensional structure is 0.1 mm to 10 mm corresponding to the height of the convex region 111. Preferably, the height of the convex region 111 is 0.5 mm to 1 mm, corresponding to the height of the convex region 111, and the depth of the concave region 121 is 0.5 mm to 1 mm.

In this embodiment, the thickness of the mask 1 is 20 um to 100 um, and the material of the reticle 1 is pure nickel. Specifically, the uniformity of the pure nickel metal plating of the reticle 1 is COV ( The coefficient of variation (variation coefficient) is less than 5%; the surface brightness of the pure nickel metal plating layer is first-order bright, no roughness, pinhole.

To further illustrate the principles and effects of the present invention, please refer to the structure drawn in FIG. 3, as shown in the figure, with reference to FIG. 3, the PCB surface 2 of the solder paste to be printed and the PCB surface 12 of the mask 1 Cooperating, so that the convex region 21 of the PCB 2 is matched with the three-dimensional structure of the mask 1. In an actual implementation, the raised region 21 of the PCB 2 is, for example, a PCB to be printed with solder paste. 2 The area of the electronic component is provided. During the printing process, the blade 3 drives the transfer material 4 to move on the printing surface 11 of the mask 1 to complete the solder paste printing.

For the three-dimensional reticle 1 , the problem to be overcome is whether the fabrication of the raised regions 111 and the recessed regions 121 is excellent, especially the positional accuracy. In the actual implementation process, in order to meet the precision requirements of the special position, and the aspect ratio of the convex region 111 and the recessed region 121 and the angle between the convex region 111 or the recessed region 121 and the vertical plate surface direction are strictly required. Therefore, it is particularly important for the selection and fabrication of the core mold, and then the bonding force between the recessed region 121 and the planar plating layer is also the focus of consideration. The convex region 111 and the recessed region 121 are mainly formed by first etching a core mold, forming a recess on the core mold, and then performing electroforming on the core mold, and peeling off after electroforming to obtain three-dimensional solids of different heights and depths. structure.

The three-dimensional nickel metal mask 1 for printing of the invention has high opening precision, and the material of the product can meet the printing requirements, and the thickness of the product can also be controlled within the required range; the 304 stainless steel core mold is used as the cathode substrate, and the plating layer is easy to peel off, and The recessed region 121 and the raised region 111 required for the angle composite are obtained, because the surface of the 304 stainless steel forms a dense oxidized surface film having an amorphous structure, which has a large crystal phase difference with the deposited layer, thereby forming electricity. The "non-bonding" property of the cast layer facilitates the peeling of the recessed regions 121.

In another embodiment, the three-dimensional structure of the three-dimensional reticle 1 for printing of the present invention has a graphic opening 13 satisfying the printing requirement, and the graphic opening on the three-dimensional structure is shown in FIG. 4 and FIG. 13 includes an upper opening and an opening larger than the upper opening (in the state shown in FIG. 5). In an actual implementation process, a soldering copper stage is disposed in a region corresponding to the graphic opening 13 of the PCB board 2. The taper of the pattern opening is 3°~8°. In practical implementations, the taper of the pattern opening may be 4°, 5°, 6° or 7° depending on the application. In other words, the raised regions 111 and the recessed regions 121 of different heights or depths can be obtained by the three-dimensional structure of the differently tapered pattern openings.

In summary, the three-dimensional mask for printing of the present invention has a plurality of pattern openings and a three-dimensional structure including a convex region on the printing surface and a recessed region on the PCB surface. The mask has three-dimensional three-dimensional convex and concave portions, and the convex and concave portions have an angle with a predetermined angle of the plate surface; the mask material is pure nickel, the precision is high; the uniformity is high, the plate The surface quality is good, bright, no rough spots, scratches, pinholes; the opening quality is good, the hole wall is smooth, no burr; the mask version has low production cost, simple technology and low energy consumption. Therefore, the present invention effectively overcomes various shortcomings in the prior art and has high industrial utilization value.

The above embodiments are intended to illustrate the principles of the invention and its effects, and are not intended to limit the invention. Any of the above-described embodiments can be modified by those skilled in the art without departing from the spirit and scope of the invention. Therefore, the scope of the invention should be as set forth in the claims of the invention.

1. . . Mask version

10, 13. . . Graphic development

11. . . Printing surface

111. . . Raised area

12. . . PCB surface

121. . . Sag area

2. . . PCB board

twenty one. . . Raised area of PCB board

3. . . scraper

4. . . Transfer material

5. . . Welding copper table

1 is a schematic view showing the structure of a three-dimensional mask for printing according to the present invention; [FIG. 2A] is a schematic view showing a three-dimensional solid region of the three-dimensional mask for printing of the present invention; [FIG. 2B] is shown as a diagram. 2A is a schematic view of a cross-sectional structure of AA; [Fig. 3] is a schematic view showing a three-dimensional mask for printing according to an embodiment of the present invention; [Fig. 4] is a view showing another embodiment of the three-dimensional mask for printing of the present invention. FIG. 5 is a schematic view showing another embodiment of the three-dimensional mask for printing according to the present invention.

1. . . Mask version

10. . . Graphic development

111. . . Raised area

Claims (10)

A three-dimensional mask for printing, comprising a substrate and a printing surface and a PCB surface on both sides of the substrate, the mask having a plurality of graphic openings and a three-dimensional structure, the three-dimensional structure comprising a protrusion on the printing surface a region and a recessed region on the surface of the PCB corresponding to the raised region. The three-dimensional mask for printing according to claim 1, wherein the three-dimensional structure has a graphic opening satisfying a printing requirement, and the graphic opening on the three-dimensional structure comprises an upper opening and a larger opening than the upper opening The lower opening has a taper of 3°~8°. The three-dimensional mask for printing according to the first aspect of the invention, wherein the recessed area of the mask and the surface of the PCB are 80° to 90°. The three-dimensional mask for printing according to claim 3, wherein the raised area is on the same line as the center of the recessed area, the line is perpendicular to the plane of the mask; the recessed area is smaller than the The area of the raised area, the three-dimensional structure is a hollow structure. The three-dimensional mask for printing according to claim 4, wherein the three-dimensional structure has a smooth hole wall. The three-dimensional mask for printing according to claim 5, wherein the height of the raised region is 0.1 mm to 10 mm. The three-dimensional mask for printing according to the sixth aspect of the invention, wherein the recessed region has a depth of 0.1 mm to 10 mm. The three-dimensional mask for printing according to claim 3, wherein the mask has a substrate thickness of 20 um to 100 um. The three-dimensional mask for printing according to claim 1, wherein the material of the mask is pure nickel. The three-dimensional mask for printing according to claim 9 , wherein: the uniform nickel (CO) coating of the mask has a coefficient of variation (COV) of less than 5%; the surface brightness of the pure nickel metal layer is one level. bright.