TWI599679B - Method of forming metal line - Google Patents

Description

Method of forming a metal wire

This invention relates to a method of forming metal wires, and more particularly to a method of forming metal wires by electroless plating.

A touch screen is a device that allows a user to control a component by touching the screen; since it provides an effective, natural, and lively human-computer interaction interface, it has been widely used in many electronic products. application.

FIG. 1 is a top view of a conventional touch panel. Referring to FIG. 1, the touch panel 10 includes a substrate 110 that can be divided into a display area 112 and a peripheral area 114. A plurality of sensing electrodes E are disposed in the display region 112, and adjacent sensing electrodes E are electrically connected through the longitudinal or lateral bridge wires C. The traces 130 disposed in the peripheral region 114 connect the series of the sensing electrodes E and the bridge wires C to the connecting portion 130a to be electrically connected to an external circuit (not shown). The bridge wire C may be made of a fine metal wire; the material of the sensing electrode E may be indium tin oxide (ITO), or may be composed of a fine metal wire M, as shown in a partially enlarged view of FIG.

A problem to be overcome with the use of fine metal wires is that, due to the highly reflective nature of the metal material itself, even if the width of the metal wire drops to the tens of microns level, it may be perceived by the user. Therefore, researchers have studied methods for reducing the visibility of metal wires. For example, referring to Figures 2 and 3, these figures illustrate two known techniques for reducing the visibility of metal wires. Figure 2 shows The technique is to first form a metal wire 402 on the substrate 400, and then form a low-reflection layer 404 on the surface of the metal wire 402. The technique shown in FIG. 3 is to first form a low-reflection layer 504 on the cover plate 500, and then in the low-reflection layer. A metal wire 502 is formed on layer 504, both of which are characterized by the placement of a low reflective layer between the metal wire and the observer's position, making the metal wire less noticeable. However, these techniques still have problems such as cumbersome steps and difficulty in controlling the size of the film layer.

The present invention provides a method of forming a metal wire that can reduce the visibility of the metal wire.

The method of forming a metal wire of the present invention comprises the following steps. Applying the photosensitive composition to the substrate; subjecting the photosensitive composition on the substrate to UV light irradiation to form a film layer containing a catalyst pattern; and applying an electroless plating method to form a metal wire; wherein the photosensitive composition Including palladium acetate, a low reflectivity material, a photoinitiator, a photopolymerizable monomer and/or oligomer, and a solvent; and the photopolymerizable monomer and/or oligomer comprises the following two components: N- Vinylpyrrolidone, and photopolymerizable monomers and/or oligomers other than N-vinylpyrrolidone.

In one embodiment, the catalyst layer-containing film layer is formed by photolithography of the photosensitive composition, or is inkjet printing, offset printing, transfer, screen printing of the photosensitive composition. It is formed by photohardening.

In one embodiment, the low reflectivity material is a material having a reflectance to visible light of less than 80%.

In one embodiment, the low reflective material comprises carbon black; a single nitride or monooxide of chromium, titanium or zirconium; or a combination of the foregoing.

In one embodiment, the low reflectivity material comprises azo dyes, anthraquinone dyes, phthalocyanine dyes, quinoneimine dyes, quinoline dyes (quinoline) Dyes), nitro dyes, carbonyl dyes, methine dyes, or combinations thereof.

In one embodiment, the step of forming the metal wire by electroless plating comprises electroless copper plating, electroless silver plating, or a combination of the two.

A method of manufacturing a touch display device of the present invention includes the aforementioned method of forming a metal wire.

The touch display device of the present invention is fabricated by the method of manufacturing the touch display device.

Based on the above, the technical solution of the present invention can produce a metal wire with low visibility through a simple program, so that the touch panel has better performance capability.

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

10‧‧‧Touch panel

100, 110‧‧‧ base

112‧‧‧ display area

114‧‧‧The surrounding area

130‧‧‧Wiring

130a‧‧‧Connecting Department

200‧‧‧Photosensitive composition

201‧‧‧ film layer

301‧‧ ‧ electroless plating

302, 402, 502‧‧‧Metal wires

304‧‧‧Low reflective material

306‧‧‧Other ingredients

404, 504‧‧‧ low reflection layer

C‧‧‧Bridge wiring

E‧‧‧Induction electrode

M‧‧‧Micro metal wire

FIG. 1 is a top view of a conventional touch panel.

Figures 2 and 3 show the combination of two conventional metal wires and a low reflection layer.

4 is a flow chart of forming a metal wire according to a first embodiment of the present invention.

In the present specification, the range represented by "a value to another value" is a schematic representation that avoids enumerating all the values in the range in the specification. Therefore, it is recorded A particular range of values is equivalent to the disclosure of any value in the range of values and the range of values defined by any value in the range of values, as in the specification. same. For example, the description of the range of "10 to 100 μm in size" is equivalent to exposing the range of "20 μm to 50 μm in size", regardless of whether other values are listed in the specification.

Figure 4 illustrates the flow of forming a metal wire. Details of one of the embodiments of the present invention will be described below with reference to FIG.

In this embodiment, the method of forming a metal wire includes the following steps.

First, the photosensitive composition 200 is applied to the substrate 100. Here, the material of the substrate 100 is not particularly limited. For example, in the manufacture of a touch display device, any transparent material suitable for the purpose, such as a glass or a plastic material, wherein the plastic material is polyethylene terephthalate (PET) or polynaphthalene. Examples of polyethylene naphthalate (PEN) and polycarbonate (polycarbonate). Further, the substrate 100 may be a rigid substrate or may have flexibility.

The photosensitive composition 200 is a composition which can be cured by irradiation of UV light and in which a catalyst for electroless plating is formed; and it is preferred to convert its contents into a catalyst by irradiation of UV light. Compositions. In this regard, the photosensitive composition 200 includes palladium acetate (chemical formula Pd(O ₂ CCH ₃ ) ₂ , or Pd(OAc) ₂ ), a photoinitiator, a photopolymerizable monomer and/or an oligomer, and a solvent. .

Palladium acetate may be added to the photosensitive composition 200 in any form, for example, palladium acetate in a state of a powder or a colloidal particle.

The photoinitiator is not particularly limited as long as it has the ability to initiate polymerization of the photopolymerizable compound, and examples thereof include: Ciba's product Darocur 1173 (2-hydroxy-2-methyl-1-phenyl-propan-1) -one, 2-hydroxy-2-methyl-1-phenyl-1-propene Ketone); product of Irfaacure 184 (1-hydroxy-cyclohexyl-phenyl-ketone, 1-hydroxycyclohexyl phenyl ketone), Irgacure 369 (2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)- 1-butanone, 2-benzyl-2-dimethylamino-1-(4-morpholinylphenyl)butanone, Irgacure 651 (2,2-dimethoxy-1,2-diphenylethan-1-one, benzoin Dimethyl ether), Irgacure 2959 (1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propane-1-one, 2-hydroxy-4'-(2-hydroxyethyl) Oxy)-2-methylpropiophenone), Irgacure 819 (phenyl bis(2,4,6-trimethylbenzoyl)phosphine oxide, phenylbis(2,4,6-trimethylbenzylidene)phosphine oxide) Irgacure 1700 (25% bis(2,6-dimethoxybenzylidene) (2,4,4-trimethylpentyl)phosphine oxide and 75% 2-hydroxy-2-methyl- Mixture of 1-phenyl-1-propanone; Mixture of 25% bis(2,6-dimethoxybenzoyl)-(2,4,4-trimethyl pentyl)phosphineoxide and 75% 2-hydroxy-2-methyl-1-phenyl- Propan-1-one)), Irgacure TPO (diphenyl(2,4,6-trimethylbenzoyl)-phosphineoxide, (2,4,6-trimethylbenzylidene)diphenylphosphine oxide). A photoinitiator may be used alone or in combination of two or more photoinitiators.

The photopolymerizable monomer and/or oligomer comprises the following two components: the first component is N-vinylpyrrolidone, and the second component comprises a photopolymerizable monomer and/or oligomer other than N-vinylpyrrolidone.

When the photosensitive composition 200 is hardened by UV light, the first component and the second component are subjected to polymerization under the action of a photoinitiator, and the two together constitute a photohardening product (film layer 201, see FIG. 4 and The polymer matrix of the initial description of 0030, in which the catalyst is interspersed, has a UV energy density of 1500-10000 J/cm ² .

The second component may be a monomer and/or an oligomer which is subjected to polymerization by a photocatalyst, and the material may be a photopolymerizable monomer known in the art to which the present invention pertains. And/or oligomers, and not belonging to N-vinylpyrrolidone, such as monofunctional, difunctional, trifunctional, tetrafunctional or hexafunctional compounds. Monofunctional compounds such as Isobornylacrylate (IBOA, such as SR506D from Sartomer), Octyl decyl acrylate (ODA, such as Sartomer's SR484), Caprolactone acrylatem (Sartomer's SR495) ) or Lauryl acrylate (such as Sartomer's SR335). Bifunctional compounds such as Tripropylene glycol diacrylate (TPGDA, such as Actilane 424 from AKZO Nobel Resins), 1,6-hexanediol diacrylate (HDDA), such as AKZO Nobel Resins Actilane 425), Dipropylene glycol diacrylate (DPGDA, such as Sartomer's SR508), Propoxylated (2) neopentyl glycol diacrylate (PONPGDA, such as Sartomer's SR9003) , Tricyclodecanedimethanol diacrylate (TCDDMDA, such as Sartomer's SR833S) or polyethylene glycol (400) diacrylate (PEG400DA, such as Sartomer's SR344). Trifunctional compounds such as trimethylol propane triacrylate (TMPTA, such as Actilane 431 of AKZO Nobel Resins), ethoxylated (3) trimethylol propane triacrylate, Such as Sartomer's SR454) or ethoxylated (6) trimethylol propane triacrylate (such as Sartomer's SR499). Tetrafunctional compounds, such as tetrafunctional polyester acrylate oligomers (such as Actilane 505 from AKZO Nobel Resins), ethoxylated pentaerythritol tetraacrylate (PPTTA, such as Actilane 440 from AKZO Nobel Resins) Or ditrimethylolpropane tetraacrylate (di TMPTA, such as Actilane 44 from AKZO Nobel Resins). Hexafunctional compound Dipentaerythritol hexaacrylate (DPHA, such as Actilane 450 from AKZO Nobel Resins).

The solvent is not particularly limited, and may be any solvent suitable for dispersing and dissolving various components of the photosensitive composition 200, such as methylethylketone, acetonitrile, ethyl acetate, chloroform, and the like, which are known in the art to which the present invention pertains. Diacetone alcohol, 3-methoxy propanol, toluene, ethyl lactate, methylcellosolve, ethylcellosolve ), propylcellosolve, ethylene glycol dimethylether, ethylene glycol diethylether, ethylene glycol methylethylether, propylene glycol dimethyl ether Propylene glycol dimethylether), propylglycol diethylether, propylene glycol methylethylether, 2-ethoxypropanol, 2-methoxypropanol, 3- 3-methoxybutanol, cyclopentanone, cyclohexanone, propyleneglycol methylether acetate, PGMEA), propyleneglycol ethylether acetate, 3-methoxybutyl acetate, ethoxyethylpropionate (EEP), ethyl 3-B Ethyl 3-ethoxy propionate, ethyl cellosolve acetate, methyl cellosolve acetate, butyl acetate or dipropylene glycol Dipropylene glycol monomethylether. One solvent may be used alone or two or more solvents may be used in combination.

In addition to the foregoing components, the photosensitive composition 200 further includes a low reflectance material. The "low reflectance" material means a material having a reflectance of visible light of 80% or less, which may be an inorganic or organic material such as carbon black; a mono-nitride or a mono-oxide of chromium, titanium or zirconium; azo Azo dyes; anthraquinone dyes; phthalocyanine dyes; quinoneimine dyes; quinoline dyes; nitro dyes; carbonyl dyes Carbonyl dyes); methine dyes or combinations thereof.

The ratio of the various components in the photosensitive composition 200 is not particularly limited in principle. When the photosensitive composition 200 is prepared, the relative proportions thereof may be adjusted according to the following factors, such as the solvent dispersing ability of each component, and the light initiation. The trade-off between the ability of the photopolymerizable monomer and/or oligomer to polymerize, the adhesion of the film layer 201 to the substrate 100, and the catalytic ability of the catalyst to subsequent electroless plating, and the like.

As shown in FIG. 4, the photosensitive composition 200 on the substrate 100 is then photocured to form a film layer 201 containing a catalyst pattern. The photosensitive composition 200 may also be baked before photocuring.

The palladium acetate present as the catalyst precursor in the photosensitive composition 200 can be reduced to metallic palladium under irradiation of UV light, and serves as a catalyst in the next electroless plating step.

In addition, it should be noted that FIG. 4 illustrates the photosensitive composition 200 as a patterned state, and this embodiment may be through inkjet printing, offset printing, transfer, screen printing photosensitive composition. 200 to carry out. After the photosensitive composition 200 is applied, the film layer 201 is formed as long as it is cured by UV light. In this embodiment, the photosensitive composition 200 may have a width of between 0.5 μm and 50 μm when initially coated on the substrate 100. Of course, the present invention can also be realized by other embodiments, for example, coating a photosensitive composition that completely covers the surface of the substrate 100, and then performing a photolithography step such as exposure, development, etc., to form the patterned film layer 201.

As shown in FIG. 4, an electroless plating method is then applied to form a film layer 301 including metal wires 302. Specifically, for example, the substrate 100 having the film layer 201 formed on the surface thereof is immersed in a plating solution containing a metal salt, and the metal ions are reduced in the film layer 201 by the action of the catalyst. Palladium position. In the present embodiment, the electroless plating step may be electroless copper plating, electroless silver plating, or a combination of the two, in other words, the resulting metal wire 302 may be a copper wire, a silver wire, or a wire having a copper-silver multilayer film structure. For details on the conditions of electroless silver plating, reference is made to the contents of European Patent Publication No. EP 0292087; for detailed conditions of electroless copper plating, reference is made to the content of International Patent Publication No. WO 2012140428, which also relates to the composition of photosensitive compositions, the reader Can be referred to together. The Applicant hereby incorporates the entire contents of the foregoing two examples, which are hereby incorporated by reference.

The film layer 301 has a thickness of between 100 nm and 2 μm and a width of between 0.5 μm and 50 μm.

Specifically, the film layer 301 includes a metal wire 302 and a low reflection material 304. Wherein, the metal wire 302 is a metal deposited by electroless plating, and the low reflection material 304 is one of the low reflection materials described in paragraph 0028. Of course, other components 306, such as photopolymerizable products remaining on the substrate 100, may also be included in the film layer 301. As described above, when the photosensitive composition 200 is irradiated with UV light, the contained first component and second component undergo polymerization to form a polymer matrix of the film layer 201. However, the first component (N-vinylpyrrolidone) is hydrophilic, so that the film layer 201 swells when electroless plating is performed, and some space communicating with the outside is generated in the film layer 201, so that the plating solution can enter the film layer 201. Internally, it contacts the catalyst and deposits metal.

In addition, the low-reflection material 304 can reduce the visibility of the metal lead 302 obtained. Therefore, the method for forming the metal wire in the embodiment is suitable for the production of the touch display device, and the display quality of the touch display device can be improved. For this reason, the present invention also relates to a method of manufacturing a touch display device and a touch display device obtained by the method.

The method of manufacturing a touch display device according to the present invention is characterized in that the method of forming a metal wire in the first embodiment is used, and other steps and materials can be arbitrarily selected from known techniques. In short, a method of manufacturing a touch display device includes forming a transparent substrate Forming a metal wire, forming a metal wire on the transparent protective layer (at least one of the two steps uses the method of the first embodiment), and bonding the transparent protective layer and the transparent substrate by an insulating adhesive layer.

In summary, the present invention provides a method of forming a metal wire, a method of manufacturing the touch display device using the same, and a touch display device obtained thereby, which can produce a metal wire with low visibility through a simple program. To make the touch panel have better performance.

Although the present invention has been described above by way of examples, it is not intended to limit the invention. Any changes and modifications may be made without departing from the spirit and scope of the invention. Therefore, the scope of protection of this application is subject to the definition of the scope of the patent application attached.

100‧‧‧Base

200‧‧‧Photosensitive composition

201‧‧‧ film layer

301‧‧ ‧ electroless plating

302‧‧‧Metal wire

304‧‧‧Low reflective material

306‧‧‧Other ingredients

Claims (8)

A method of forming a metal wire comprising: applying a photosensitive composition to a substrate; subjecting the photosensitive composition on the substrate to UV light curing to form a film layer containing a catalyst pattern; and applying an electroless plating method to form a metal a wire; wherein the photosensitive composition comprises Palladium acetate, a low reflectivity material, a photoinitiator, a photopolymerizable monomer and/or an oligomer, and a solvent, and the photopolymerizable monomer and/or Or the oligomer comprises: N-vinylpyrrolidone, and a photopolymerizable monomer and/or oligomer other than N-vinylpyrrolidone, wherein the catalyst in the catalyst layer-containing film layer is palladium and is UV light It is formed by irradiating palladium acetate. The method of claim 1, wherein the film layer containing the catalyst pattern is formed by photolithography of the photosensitive composition, or by inkjet printing, offset printing, transfer printing, screen printing. The photosensitive composition is formed by UV-curing. The method of claim 1, wherein the low reflectance material is a material having a reflectance of visible light of 80% or less. The method of claim 1, wherein the low reflective material comprises carbon black; a single nitride or monooxide of chromium, titanium or zirconium; or a combination of the foregoing. The method of claim 1, wherein the low reflectivity material comprises azo dyes, anthraquinone dyes, phthalocyanine dyes, quinoneimine dyes. ), quinoline dyes, nitro dyes, carbonyl dyes, methine dyes, or combinations thereof. The method of claim 1, wherein the forming is performed by electroless plating The steps of the metal wires include electroless copper plating, electroless silver plating, or a combination of the two. A method of manufacturing a touch display device, comprising the method of forming a metal wire according to any one of claims 1 to 6. A touch display device is manufactured by the method for manufacturing a touch display device according to claim 7.