JP2009186645A - Member for display substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a member for display substrate which can endure chemicals treatment and high-temperature treatment in a display manufacturing process, has high gas barrier performance after the manufacturing thereof, leaves no silicone resin layer in the final product and is suitable for manufacturing a display having features such as being thin, light in weight, bendable and flexible. <P>SOLUTION: In the member for display substrate, a glass plate having a thickness of 10-75 μm, a silicone resin layer having a thickness of 1-500 μm and a support are layered in the order, wherein the support is a metal sheet or a plastic sheet. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a thin display substrate member such as a liquid crystal display, an organic EL display, and electronic paper.

  Thin and lightweight displays are increasingly used in applications such as televisions, personal computers, mobile phones, portable audiovisual devices, PDAs (Personal Digital Assistants), and electronic paper. Expected. Furthermore, the market formation of thin displays with increased added value such as flexible and bendable is also expected.

  In order to realize a flexible display, in addition to being flexible in the substrate, it depends on the durability required by the display method and application, but it has a gas barrier property against water vapor, oxygen, etc. for suppressing deterioration of the display material. Desired. In addition, the substrate material is required to have heat resistance and chemical resistance as resistance to the manufacturing process.

In order to meet the above requirements, a material in which a gas barrier layer is formed on a transparent plastic film such as a polycarbonate film or a polyester film has been proposed (see Patent Documents 1 and 2). With such materials, flexibility can be easily obtained, but it is difficult to achieve a water vapor transmission rate of 10 ⁻⁶ g / m ² / day required for an organic EL display or the like. There is a problem that it is difficult to withstand a process at a substrate temperature of about 220 ° C. in order to sufficiently reduce the resistivity of ITO that is formed and used as a transparent electrode. A technique for forming a polymer has been proposed (see Patent Document 3). With such a material, it is considered that a display substrate that can achieve any of flexibility, gas barrier property, and heat resistance can be obtained depending on conditions and material selection. However, with this technology, the silicone polymer layer cannot be removed from the substrate. Therefore, when the silicone polymer layer surface is used as the inner surface of the display, it is difficult to form a wiring layer on the silicone polymer layer. Is used as the display outer surface (atmosphere side), there is a problem that it is difficult to provide an optical film or a hard coat layer due to the low adhesion of the silicone polymer surface. In addition, even when the silicone resin layer is left in the final product, the glass and silicone resin composite is so soft that it is difficult to handle in the element formation process on the glass, and the position system during microfabrication is difficult to appear. There are challenges.

Moreover, the technique of patent document 4 is known as a technique which uses a glass plate as a support body and forms a silicone resin layer on it. Also in this technique, since the glass plate is used as a support, the silicone resin layer cannot be removed.
JP 2000-338901 A (Claims) JP 2007-268711 A (Claims) JP-T-2002-534305 Publication (Claims) JP 2007-67382 A (Claims)

  The present invention provides a substrate member suitable for a thin display that is lightweight, flexible, heat resistant, and has high gas barrier properties.

  That is, the present invention is a display substrate member in which a glass plate having a thickness of 10 μm to 75 μm, a silicone resin layer having a thickness of 1 μm to 500 μm, and a support are laminated in this order, and the support is a metal sheet or a plastic sheet. .

  According to the present invention, the display manufacturing process can withstand chemical treatment and high-temperature processing, has high gas barrier properties after manufacturing, and does not leave a silicone resin layer in the final product, and is thin, light, bendable, flexible It is possible to provide a display substrate member suitable for manufacturing a display having the above characteristics.

  The member for a display substrate of the present invention is a glass plate having a thickness of 10 μm or more and 75 μm or less, a silicone resin layer having a thickness of 1 μm or more and 500 μm or less, and a support laminated in this order, and the support is a metal sheet or a plastic sheet. is there.

  The display substrate member of the present invention is used when manufacturing thin displays such as a liquid crystal display, an organic EL display, a plasma panel display, and electronic paper, and is laminated on a support via a silicone resin layer. On a thin glass plate, transparent electrode formation, TFT formation, color filter processing, and the like, which are normal flat panel manufacturing processes, can be performed. Lightweight, flexible, high gas barrier property, and transparent made of thin glass plate by peeling the support and silicone resin layer from the thin glass plate according to the process after final processing or between multiple processing A display substrate having characteristics can be realized.

  The metal sheet used in the present invention may be either a thin foil with a flexible shape, or a plate with no flexibility. When having flexibility, when peeling a metal sheet from a glass plate, for example, it is possible to peel off the sticker from the release paper, so the sheet surface while bending the metal sheet without applying too much bending stress to the thin glass plate There is an advantage that it can be peeled off in a direction having a component perpendicular to. The higher the flexibility of the metal sheet, the smaller the stress applied to the thin glass plate during peeling. Moreover, since it is rich in flexibility as a member for a substrate, there is an advantage that it can correspond to the production of roll-to-roll. On the other hand, when the metal sheet is not very flexible, there are advantages in that the handling of the substrate is easy in the flat panel manufacturing process, the dimensional stability as the substrate member is high, and the fine processing is easy to apply. When peeling a metal sheet that is not very flexible, the stress applied to the thin glass plate at the time of peeling can be reduced by performing a treatment such as swelling the silicone resin layer with a solvent to weaken the adhesive force. In addition, it is also possible to remove the metal sheet by dissolving it with a chemical solution.

  Although the material of the metal sheet used for this invention is not specifically limited, For example, copper, aluminum, iron, zinc, nickel, chromium, gold | metal | money, silver, these alloys, stainless steel etc. can be used preferably. It can be appropriately selected from the viewpoint of required characteristics such as strength, linear expansion coefficient, chemical resistance, and cost.

  The thickness of the metal sheet used for this invention is not specifically limited. In order to enhance flexibility, the thickness is preferably 100 μm or less, and in order to ensure strength, it is preferably 1 μm or more.

  The plastic sheet used in the present invention may be either a thin film having a flexible shape, or a plate having no flexibility. If it has flexibility, when peeling the plastic sheet from the glass plate, for example, it can be peeled off to remove the sticker from the release paper, so the sheet surface while bending the plastic sheet without applying too much bending stress to the thin glass plate There is an advantage that it can be peeled off in a direction having a component perpendicular to. The higher the flexibility of the plastic sheet, the smaller the stress applied to the thin glass plate during peeling. Moreover, since it is rich in flexibility as a member for a substrate, there is an advantage that it can correspond to the production of roll-to-roll. On the other hand, when the plastic sheet is not very flexible, there is an advantage that the handling of the substrate is easy in the flat panel manufacturing process, the dimensional stability as the substrate member is relatively high, and the fine processing is easily applied. When peeling a plastic sheet that is not very flexible, the stress applied to the thin glass plate at the time of peeling can be reduced by performing a treatment such as swelling the silicone resin layer with a solvent to weaken the adhesive force. In addition, it is also possible to remove the plastic sheet by dissolving it with a chemical solution. In addition, when a transparent material is used for the plastic sheet, the thin glass plate can be seen through the plastic sheet, and there is an advantage that alignment recognition and inspection can be performed using this in the flat panel manufacturing process. is there.

  The material of the plastic sheet used in the present invention is not particularly limited. Polycarbonate, polyethylene terephthalate, polyethylene naphthalate, polyethersulfone, polyimide, epoxy resin, phenol resin, melamine resin, polyurethane, polyurea, polyethylene, polypropylene, nylon resin, polyvinyl chloride, acrylic resin, polystyrene, acrylonitrile butadiene styrene resin, Acrylonitrile styrene resin, polyvinylidene chloride and the like can be used.

  The thickness of the plastic sheet used in the present invention is not particularly limited. In order to enhance flexibility, the thickness is preferably 500 μm or less, in order to ensure strength, it is preferably 1 μm or more, and more preferably 25 μm or more in view of ease of handling.

  The thin glass plate used in the present invention has a thickness of 10 μm or more and 75 μm or less. When the thickness is 10 μm or more, it is easy to obtain strength exceeding the practical level. When the thickness is 75 μm or less, the flexibility becomes remarkable, and the usability as a bendable display or a flexible display substrate increases. Such a thin glass plate can be obtained as a commercial product as a thin glass plate such as D263T or AF45 manufactured by SCHOTT AG. Non-alkali glass is preferably used as the glass material for display.

  A transparent electrode for pixel driving of the display can be formed on the surface of the thin glass plate where the silicone resin layer is not formed. The transparent electrode can be formed by sputtering of an ordinary ITO layer and chemical pattern etching.

  When the silicone resin layer is removed from the thin glass together with the metal sheet or plastic sheet, the adhesive force between the silicone resin layer and the metal sheet or plastic sheet may be set larger than the adhesive force between the silicone resin and the thin glass. As a result, when the metal sheet or plastic sheet is peeled, the peeling interface is between the thin glass and the silicone resin layer, and the silicone resin is peeled from the thin glass substrate together with the metal sheet or plastic sheet. When the silicone resin remains on the glass substrate surface after the silicone resin layer is peeled off at a molecular level, the silicone resin can be completely removed by performing oxygen plasma treatment or the like as necessary.

  Since the fully cured silicone resin surface is generally difficult to obtain adhesion with other materials, if the silicone resin layer is not used as the outermost surface, after removing the silicone resin layer from the thin glass surface, Preferably the material is formed. In such a case, the optical functional layer can be formed directly on the surface of the thin glass as required by coating or film bonding.

  When leaving the silicone resin layer on the thin glass and peeling the metal sheet or plastic sheet, the adhesive force between the silicone resin layer and the metal sheet or plastic sheet should be less than the adhesive force between the silicone resin and the thin glass. That's fine. As a result, when the metal sheet or plastic sheet is peeled off, the peeling interface is between the silicone resin layer and the metal sheet or plastic sheet, the silicone resin layer remains on the thin glass, and the metal sheet or plastic sheet is peeled off. The

  When the interface to be peeled is a silicone resin layer and a plastic sheet or a metal sheet, the adhesive force at the peeling interface is 0.01 N / cm or more and 3 N / cm or less in both cases of silicone resin and thin glass. Is preferred. If this interfacial adhesive strength is 0.01 N / cm or more, unintentional peeling is unlikely to occur during the flat panel manufacturing process, and if this interfacial adhesive strength is 3 N / cm or less, the thin glass is damaged during peeling. It becomes difficult to give. The adhesive force here refers to the stress when the conductor layer is peeled from the support and the cured silicone resin layer at a rate of 50 mm / min in the direction of 90 degrees, and the measuring method is 5.7 peel of JIS-C6481. Strength, 5.7.3 (1) Complies with measurement under normal conditions.

  The silicone resin layer used in the present invention is obtained by curing a silicone resin as a main component. The following two types (1) and (2) of the silicone resin constituting the silicone resin layer are excellent in heat resistance and chemical resistance necessary for producing a multilayer wiring layer on a wiring board forming carrier. It is preferable in terms of excellent peelability from the produced multilayer wiring layer.

(1) Silicone resin obtained by condensation reaction As a method for forming such a condensation-type silicone resin, a molecular weight of several thousands represented by the following general formula [1] having a hydroxyl group or a vinyl group in the main chain or at the end of the main chain A method of crosslinking ˜hundreds of thousands of linear organic polysiloxane with a crosslinking agent is common.

n is an integer of 2 or ^more, R 1, ^{R 2} is a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or non-4-50 carbon atoms At least one selected from the group of substituted aryl groups, which may be the same or different. It is preferable that 40% or less of R ¹ and R ² are vinyl, phenyl, vinyl halide, and phenyl halide, and 60% or more of the whole is a methyl group.

  Such a linear organic polysiloxane can be made into a further crosslinked silicone resin by adding an organic peroxide and subjecting it to a heat treatment. Such a linear organic polysiloxane can be cross-linked by adding a cross-linking agent as represented by the general formula [2].

q is an integer of 0 to 2, and R ³ represents an alkyl group, an alkenyl group, an aryl group, or a combination thereof, which includes a halogen atom, an amino group, a hydroxyl group, an alkoxy group, an aryloxy group, ( It may have a functional group such as a (meth) acryloxy group or a thiol group as a substituent. Z is a hydrogen atom, a hydroxyl group, an alkoxy group, an acyloxy group, a ketoxime group, an amide group, an aminooxy group, an amino group, a glycidyl group, a methacryl group, an allyl group, a vinyl group, etc., acetoxysilane, ketoximesilane, alkoxysilane, Amino silane, amido silane and the like can be mentioned, but not limited thereto.

  In the synthesis of such a condensation-type silicone resin, it is optional to add a compound containing a metal such as tin, zinc, lead, calcium, manganese or the like as a catalyst.

(2) Silicone resin obtained by addition reaction As a method for forming an addition-type silicone resin, a polysiloxane compound having two or more ethylenically unsaturated bonds in the molecule is reacted with a polyvalent hydrogen polysiloxane compound. The method is common. Examples of the polysiloxane compound having two or more ethylenically unsaturated bonds in the molecule include α, ω-divinylpolydimethylsiloxane, (methylvinylsiloxane) (dimethylsiloxane) copolymer having methyl groups at both ends. Examples of the polyvalent hydrogen polysiloxane compound include α, ω-dimethylpolymethylhydrogensiloxane, (methylpolymethylhydrogensiloxane) (dimethylsiloxane) copolymer having methyl groups at both terminals. To such an addition type silicone resin, platinum alone, platinum chloride, olefin coordinated platinum or the like is added as a catalyst.

  When an addition type silicone resin is formed on a support, in order to obtain a strong adhesion between the support and the cured addition type silicone resin layer, the support should be a support that does not contain phosphorus atoms, nitrogen atoms, or sulfur atoms. It is preferable to use it. When phosphorus atoms, nitrogen atoms, and sulfur atoms are present on the support, the addition-type silicone resin is likely to be poorly cured, and a long curing time may be required.

  The silicone resin layer used in the present invention has a thickness of 1 μm to 500 μm, more preferably 3 μm to 100 μm. If the silicone resin layer has a thickness of 1 μm or more, it becomes easy to produce a continuous film of the silicone resin layer, and if it is 3 μm or more, sufficient adhesion between the metal sheet or plastic sheet and the silicone resin layer, and the silicone resin layer and glass This is preferable because sufficient adhesive strength between the plates can be easily obtained. When the silicone resin layer is 500 μm or less, warping after forming the silicone resin layer on the support is less likely to occur, and when it is 100 μm or less, the drying time of the silicone resin layer is preferably shortened.

  Further, the silicone resin layer used in the present invention has a property of absorbing and swelling an organic solvent after curing. By this swelling, the thin glass plate formed on the support via the silicone resin layer can be easily peeled off. The swelling ratio of the silicone resin layer is preferably in the range of 10% by weight to 500% by weight. More preferably, it is the range of 50 weight% or more and 500 weight% or less. When the swelling ratio is 10% by weight or more, the thin glass plate formed on the support through the silicone resin layer can be peeled off in a short time. When the swelling ratio is 500% by weight or less, the problem that the silicone resin layer remains on the wiring board is less likely to occur.

  The organic solvent for swelling the silicone resin layer is not particularly limited as long as it allows the silicone resin layer to fall within the range of the swelling rate. However, hydrocarbon solvents having 5 or more carbon atoms, alcohol solvents, ethers. Solvents such as solvents, glycol ether solvents, and olefin hydrocarbon solvents having an unsaturated double bond group can be used. Examples of the hydrocarbon solvent having 5 or more carbon atoms include pentane, 2-methylbutane, heptane, 2-methylhexane, octane and 2-methylheptane. Moreover, what added water to the organic solvent may be used. In addition, a surfactant or an antifoaming agent may be added.

  Since the adhesive force between the support and the silicone resin layer used in the present invention is important, the surface for obtaining sufficient adhesion between the support and the silicone resin layer before applying the silicone resin on the support. The surface treatment method may include low temperature plasma treatment or providing a primer layer on the surface of the support.

  The primer layer is not particularly limited as long as it improves the adhesive force between the support and the silicone resin layer. For example, a coupling agent such as a silane coupling agent or a titanium coupling agent, a phenol resin type, an acrylic type, a polyamide type, a polyimide type, a polyester type, an ultraviolet curable resin type, or a urethane type material can be preferably used. Since it is excellent in heat resistance especially, a silane coupling agent, a phenol type, and a polyimide type are used more preferably. As the silane coupling agent, an aminosilane-based agent can be preferably used from the viewpoint of obtaining high adhesive strength.

Moreover, you may use what carried out the low-temperature plasma process beforehand on the support body surface which provides a primer layer. As the low temperature plasma treatment, for example, an aluminum electrode is used as the discharge electrode, and the support is subjected to corona discharge treatment under the condition of an electrode density of 250 (W · min / m ² ).

  The display substrate member of the present invention is manufactured, for example, as follows. First, a reverse coater, a calender roll coater, a knife coater, and a Mayer coater are used to form a composition solution to be formed as a silicone resin layer on a support whose surface has been subjected to primer treatment or low-temperature plasma treatment to improve adhesion as necessary. Apply using an ordinary coater such as a rotary coater such as a hoera and dry. Drying is usually performed by heat treatment at a temperature of 60 to 180 ° C. for several minutes.

  Next, a thin glass plate is overlaid on the cured silicone resin layer of the display substrate member obtained in this manner, and is pressed by a press, a roll laminator or the like. Conditions such as temperature and pressure can be arbitrarily selected. In this way, a flexible display substrate member having excellent gas barrier properties can be obtained.

  The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

The gas barrier property was evaluated by the water vapor transmission rate. For the water vapor transmission rate, a metal calcium film having a thickness of 100 nm was formed by vapor deposition on the glass surface of the display substrate member, and then a metal aluminum film having a thickness of 300 nm was formed by vapor deposition so as to cover the end surface of the calcium film. Next, it was taken out from the vacuum deposition apparatus, and the Al surface side was molded with resin so as to cover the end surface of the display substrate. This was used as a measurement sample, placed in an environment of 40 ° C. and 90% relative humidity, and the time change of the calcium film was photographed with a CCD camera using a microscope from the surface opposite to the calcium deposition surface of the display substrate member. The reaction between calcium and water is Ca + 2H ₂ O → Ca (OH) ₂ + H ₂ , and 1 mol of calsim reacts with 2 mol of water to produce calcium hydroxide. When metallic calcium changes to calcium hydroxide, the reflectance decreases, so the amount of change can be quantified by observing the calcium film surface. Specifically, first, the image photographed by the CCD is binarized, the black part is defined as a region where the metal calcium is changed to calcium hydroxide, and the volume of calcium hydroxide is determined from the thickness of the calcium film with the area of the black part. Calculated. Subsequently, the weight of calcium hydroxide was calculated | required by specific gravity calculation, and the permeated water content was calculated | required using this.

Example 1
A 50 μm thick polyester film (manufactured by Toray Industries, Inc .: “Lumirror”) is used as a support, and a primer layer having the following composition is applied to the surface so that the film thickness after curing is 2 μm. After drying at 2 ° C. for 2 minutes, the film was exposed and cured at an illuminance of 15 mW / cm ² for 5 minutes with a UV meter (Oak Manufacturing Light Major Type UV365) using a 3 kW ultra high pressure mercury lamp (manufactured by Oak Manufacturing).

  The primer layer composition was 100 parts by weight of a copolymer of 2-hydroxyethyl methacrylate / 2-hydroxylethyl acrylate / methyl methacrylate / methyl acrylate = 20/20/30/30, 250 parts by weight of N-dimethylformamide, 650 tetrahydrofuran. It was prepared by mixing parts by weight.

Subsequently, a silicone resin layer having the following composition was applied on the primer layer so that the film thickness after drying was 5 μm, and heat-treated at 140 ° C. for 2 minutes. The silicone resin is 100 parts by weight of polydimethylsiloxane (average molecular weight 50,000) having both vinyl groups, (CH ₃ ) ₃ SiO ((Si (CH ₃ ) ₂ O) _30- (SiH (CH ₃ ) O). ₁₀ ) 6 parts by weight of Si (CH ₃ ) ₃ , 0.3 part by weight of chloroplatinic acid / methylvinyl cyclic complex, and 450 parts by weight of hexane were mixed.

  On the silicone resin layer, a thin glass plate having a thickness of 50 μm (manufactured by SHOTTT AG, a product having a thickness of 50 μm in microsheet # 100) was superimposed to obtain a member for a display substrate.

  When this display substrate member was bent at a radius of 30 mm with the thin glass surface facing outside, no cracks or cracks occurred in any place.

The water vapor transmission rate of the substrate member for display was measured under an environment of 40 ° C. and a relative humidity of 90% and found to be 1 × 10 ⁻⁵ g / m ² / day or less.

  Moreover, the interface adhesive force of the member for display substrates produced above was evaluated as follows. It is cut into a width of 25 mm and a length of 300 mm, and this is fixed to a stainless steel plate having a thickness of 2 mm using a double-sided adhesive tape. At this time, the thin glass plate surface is adhered to the adhesive surface of the double-sided adhesive tape. Next, the polyester film was peeled off at a speed of 200 mm / min in the direction of 90 degrees, and the adhesive force was measured. The adhesive force was 1 N / cm, and the peeling interface was an interface between a thin glass plate and a silicone resin. From this, it was determined that the interfacial adhesive force between the polyester film and the thin glass plate was larger than the adhesive force at the interface between the thin glass plate and the silicone resin.

Example 2
Example 1 except that a silicone resin layer was directly formed without forming a primer layer on the glossy surface of 12 μm thick electrolytic copper foil (manufactured by Furukawa Circuit Foil Co., Ltd .: model number F0-WS) as a support. A display substrate member was produced in the same manner as described above.

  When this display substrate member was bent at a radius of 30 mm with the thin glass surface facing outside, no cracks or cracks occurred in any place.

  When the interface adhesive force of the display substrate member was evaluated in the same manner as in Example 1, the adhesive force was 1 N / cm, and the peeling interface was an interface between a thin glass plate and a silicone resin. Moreover, it was judged from this that the interface adhesive force between the copper foil and the thin glass plate was larger than the adhesive force at the interface between the thin glass plate and the silicone resin.

An ITO film having a thickness of 150 nm was deposited on the thin glass surface of the display substrate member at a substrate temperature of 240 ° C. The sheet resistance of the ITO film measured by the 4-terminal method was 10Ω / □. Subsequently, a mask was prepared on the ITO film by a lithography process using a normal photoresist and etched with a mixed aqueous solution of ferric chloride and hydrochloric acid to obtain an ITO pattern of line and space = 20 μm / 20 μm. When the water vapor transmission rate of this sample was measured under an environment of 40 ° C. and a relative humidity of 90%, it was 1 × 10 ⁻⁵ g / m ² / day or less.

Comparative Example 1
A display substrate member was produced in the same manner as in Example 1 except that a thin glass plate having a thickness of 100 μm (manufactured by SHOTTT AG, microsheet # 100 having a thickness of 100 μm) was used.

  When this display substrate member was bent at a radius of 30 mm with the thin glass surface facing outside, cracks occurred in the thin glass plate.

The water vapor transmission rate of the substrate member for display was measured under an environment of 40 ° C. and a relative humidity of 90% and found to be 1 × 10 ⁻⁵ g / m ² / day or less.

Claims (3)

A display substrate member in which a glass plate having a thickness of 10 μm to 75 μm, a silicone resin layer having a thickness of 1 μm to 500 μm, and a support are laminated in this order, and the support is a metal sheet or a plastic sheet. 2. The display substrate member according to claim 1, wherein an adhesive force between the metal sheet or plastic sheet and the silicone resin layer is larger than an adhesive force between the silicone resin layer and the glass plate. 2. The display substrate member according to claim 1, wherein a transparent electrode layer is formed on a glass surface opposite to the glass surface on which the silicone resin layer is formed.