JP2005317837A - Method of manufacturing printed wiring - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide the method of manufacturing printed wiring in which there is no possibility of conduction, even if the number of wiring portions is increased and the portions are miniaturized. <P>SOLUTION: There is no possibility of conduction between wiring portions A1 and A2, even if the numbers of wiring portions B1 and B2 are increased and the widths of insulating walls A1 and A2 are decreased, since the insulating walls A1 and A2 of insulant ink are previously formed by curing, and then the wiring portions B1 and B2 of conductive material ink are formed between the insulating walls A1 and A2. Further, there is no possibility of decrease in manufacture efficiency since the insulant ink is cured in a small amount of time by UV or heating. The deterioration of the wiring portions B1 and B2 is prevented since the wiring portions B1 and B2 are covered by insulating layers C1 and C2 constituted by curing the insulant ink. Further, highly efficient printed wiring is formed by forming layered wiring D1 and D2 in a multilayered manner. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for producing printed wiring using ink jet printing.

A technique for forming a thin-film printed wiring on a substrate using ink jet printing is known. In this type of wiring forming method, both the insulating material ink and the conductive material ink are simultaneously ejected onto the surface of the base material by an ink jet method, and both ejected inks are heated and cured. By doing so, the conductive material ink is solidified to form a plurality of wiring portions, and the contact between the wiring portions is a printed wiring that is blocked by the solidified insulating material ink (for example, Patent Document 1). .)
JP 11-163499 A

  However, in such a conventional technique, the insulating material ink and the conductive material ink used in ink jet printing have a relatively low viscosity, and these inks are ejected at the same time. If the width of the insulating material ink decreases and the width of the insulating material ink decreases by that amount, the conductive material inks adjacent to each other through the insulating material ink may break and mix part of the insulating material ink, resulting in a conductive state. Therefore, conventionally, a large number of fine wiring portions cannot be formed.

  The present invention has been made by paying attention to such a conventional technique, and provides a printed wiring manufacturing method that does not have a possibility of conduction even when the number of wiring portions is increased and miniaturized.

  According to the first aspect of the present invention, an insulating material ink is printed on the surface of a substrate by an ink jet method, the printed insulating material ink is cured by UV or heating to form an insulating wall, and an ink jet is provided between the cured insulating walls. A conductive material ink is printed by a method, the printed conductive material ink is cured to form a wiring portion, and a thin layered wiring is formed by the insulating wall and the wiring portion.

  The invention according to claim 2 is characterized in that an insulating material ink is printed on the entire surface of the formed layered wiring by an ink jet method, and the printed insulating material ink is cured to form an insulating layer covering the wiring portion. .

  The invention described in claim 3 is characterized in that the required number of layered wirings and insulating layers are repeatedly formed on the surface of the insulating layer.

  The invention according to claim 4 is characterized in that a via hole portion in which an insulating layer is not formed is set.

  According to the first aspect of the present invention, since the insulating wall made of the insulating material ink is first cured and then the wiring portion made of the conductive material ink is formed between the insulating walls, the number of wiring portions increases. By miniaturization, even if the width of the insulating wall is reduced, there is no possibility that the wiring portions are electrically connected. Further, since the insulating material ink is cured in a short time by UV or heating, the production efficiency is not lowered.

  According to the second aspect of the present invention, since the wiring portion is covered with the insulating layer obtained by curing the insulating material ink, the deterioration of the wiring portion can be prevented.

  According to the third aspect of the present invention, high-performance printed wiring can be formed by forming the layered wiring in multiple layers.

  According to the fourth aspect of the present invention, since the insulating layer is not formed in the via hole portion, when the multilayer is formed, the via hole portion can be used to electrically connect the layers.

  For the purpose of providing a printed wiring manufacturing method that does not cause electrical conduction even when the number of wiring portions is increased and miniaturized, an insulating ink is printed on the surface of the substrate by an inkjet method, and the printed insulating ink is used. Insulating walls are formed by curing by UV or heating, conductive material ink is printed between the cured insulating walls by an inkjet method, and the printed conductive material ink is cured to form a wiring portion. This was realized by forming a thin layered wiring.

  An embodiment of the present invention will be described below with reference to FIGS.

  In this embodiment, a printed wiring 2 formed on the inner surface of an air conditioning duct 1 in an automobile will be described. The duct 1 has a cylindrical shape with its tip branched into three parts, and can be divided into two parts in the vertical direction, and FIG. 1 shows its lower half.

  Each of the ducts 1 divided into three is provided with a thermistor 3 for temperature measurement, and two printed wirings 2 from each thermistor 3 are assembled to the base end portion. The thermistor 3 and the conductive part inside the printed wiring 2 are connected by a conductive adhesive or soldering. A signal from the thermistor 3 is transmitted to a control unit (not shown) via the printed wiring 2.

  The formation of each printed wiring 2 on the inner surface of the duct 1 that is a “base material” utilizes an ink jet printing method. That is, the inkjet nozzle 4 that supports the duct 1 on a gantry of an inkjet printing apparatus (not shown) and moves while maintaining a certain distance from the surface of the duct 1 is used.

  From the inkjet nozzle 4, the insulating material ink and the conductive material ink can be separately discharged. The insulating material ink is mainly composed of a UV curable resin that is cured by being irradiated with ultraviolet rays (UV). The conductive material ink is mainly composed of a thermosetting resin in which silver powder is dispersed.

  The printed wiring 2 has a two-layer structure, and a manufacturing method thereof will be described with reference to FIG. First, using the inkjet nozzle 4, the linear insulating material ink is printed on the back side surface of the duct 1 with a predetermined interval. Then, the insulating material ink is irradiated with UV and cured to form a first insulating wall A1 [FIG. 3 (a)]. Since the insulating material ink is cured with UV in a short time, the production efficiency is good.

  Then, using the inkjet nozzle 4, the conductive material ink is printed between the first insulating walls A1, and is cured by heating to form the first wiring part B1 [FIG. 3 (b)]. The first wiring portion B1 and the first insulating wall A1 form a first layered wiring D1 having a predetermined width. The first layered wiring D1 is formed by first curing the first insulating wall A1 made of the insulating material ink, and then forming the first wiring portion B1 made of the conductive material ink. In addition, even if the width of the first insulating wall A1 is reduced and refined, there is no possibility that the second wiring parts B2 are electrically connected to each other.

  Further, an insulating material ink is printed on the entire surface of the first layered wiring D1 except for the via hole portion 5, and is UV cured to form the first insulating layer C1 [FIG. 3 (c)]. Since the first wiring part B1 is covered with the first insulating layer C1 and does not come into contact with air, it is possible to prevent the first wiring part B1 from being deteriorated.

  Subsequently, a second insulating wall A2 is formed on the surface of the first insulating layer C1 in the same manner as before except for the portion related to the via hole portion 5 ([FIG. 3 (d)]).

  Then, the second wiring part B2 and the interlayer connection wiring part 6 are formed between the second insulating walls A2 ([FIG. 3 (e)]. The interlayer connection wiring part 6 is connected to the first wiring via the via hole part 5. The second wiring layer D2 is formed by the second wiring portion B2 and the interlayer connection wiring portion 6 and the second insulating wall A2.

  Finally, the second insulating layer C2 is formed on the surface of the second layer wiring D2, and the printed wiring 2 having a two-layer structure is completed ([FIG. 3 (f)]. FIG. 3 schematically shows the structure. However, the actual width dimension is sufficiently smaller than that shown in the figure, and the third and fourth layered wirings can be formed following the second layered wiring D2.

  Since the printed wiring 2 of this embodiment is in the form of a thin film, even if it is provided on the inner surface of the duct 1 through which air-conditioned air passes, there is no ventilation resistance. Further, since the insulating material ink and the conductive material ink itself have adhesiveness to the inner surface of the duct 1, the adhesiveness with the duct 1 is maintained without using any adhesive. In addition, since the inkjet method, which is a non-contact printing method, is used, even if the printing surface is curved or has some unevenness, the printing can be reliably performed as long as the ink can be accurately ejected from the inkjet nozzle 4. Yes. Further, by moving the inkjet nozzle 4 in the printing direction and making it movable in the contact / separation direction with respect to the printing surface, it is possible to perform printing corresponding to the shape change.

  In the above embodiment, an example in which the insulating material ink is cured by UV is shown, but a type in which the insulating material ink is cured by heating may be used. Moreover, although the example in which the conductive material ink is cured by heating has been shown, a type that is cured by UV may be used. When the insulating layer is not formed, the conductive material ink may be naturally cured by evaporation drying.

The perspective view which shows the printed wiring formed in the duct which concerns on one Example of this invention. The perspective view which shows the printing method by the inkjet nozzle given to the duct of FIG. (A)-(f) is sectional drawing which shows the manufacturing process of the printed wiring given to the duct shown in FIG. 2, respectively.

Explanation of symbols

1 Duct (base material)
2 Printed wiring 3 Thermistor 4 Inkjet nozzle 5 Via hole portion 6 Interlayer connection wiring portion A1 First insulating wall A2 Second insulating wall B1 First wiring portion B2 Second wiring portion C1 First insulating layer C2 Second insulating layer D1 First Layered wiring D2 Second layered wiring

Claims (4)

Insulating material ink is printed on the surface of the substrate (1) by an inkjet method,
The printed insulating ink is cured by UV or heating to form an insulating wall (A1),
Print conductive material ink between the cured insulating walls (A1) by ink jet method,
The printed conductive material ink is cured to form the wiring part (B1),
A method of manufacturing a printed wiring, wherein a thin layered wiring (D1) is formed by an insulating wall (A1) and a wiring part (B1). It is a manufacturing method of the printed wiring according to claim 1,
Insulating material ink is printed on the entire surface of the formed layered wiring (D1) by an inkjet method,
A method for producing a printed wiring, wherein the printed insulating material ink is cured to form an insulating layer (C1) that covers the wiring portion (B1). It is a manufacturing method of the printed wiring according to claim 2,
A method for producing a printed wiring, comprising repeatedly forming a required number of layered wirings (D2) and insulating layers (C2) on the surface of the insulating layer (C1). It is a manufacturing method of the printed wiring according to claim 3,
A method for manufacturing a printed wiring, characterized in that a via hole portion (5) not forming an insulating layer (C1) is set.

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