JP2012083659A - Method for manufacturing glass substrate for electronic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method which is capable of efficiently manufacturing many glass substrates for electronic devices from one glass base material.SOLUTION: The manufacturing method includes: a first step (ST2) of forming a thin film layer on a front surface and/or a rear surface of a glass substrate divided into a plurality of regions for use; a second step (ST4) of covering the entire glass substrate with a protective film so as to wrap the glass substrate subjected to the first step; a third step (ST5 to ST6) of mechanically cutting the glass substrate covered with the protective film together with the protective film into glass substrates per region for use; a fourth step (ST7) of peeling the protective film from individual glass substrates separated by cutting; and a fifth step (ST8) of bonding a sheet material to a front surface and/or a rear surface of each glass substrate from which the protective film has been peeled.

Description

  The present invention relates to an electronic device having a cover glass and a touch panel, and more particularly to a method of manufacturing a glass substrate for an electronic device that can efficiently manufacture a large number of completed glass substrates from a single glass base material.

  Portable small computer devices such as cellular phones, portable music players, and portable personal computers are becoming widespread. And the cover glass which covers these display apparatuses is not only limited to the use which protects an electronic device, but often exhibits an additional function as a touch panel.

  On the other hand, these portable electronic devices are strongly demanded not only for miniaturization but also for weight reduction, and are also exposed to intense price competition.

  Under such circumstances, in order to manufacture a cover glass and a touch panel, it is conceivable to cut a large number of completed glass substrates from one glass base material. Here, it is conceivable to cut out the glass substrate by chemical polishing, but it is advantageous to cut and separate mechanically in order to reduce the manufacturing cost.

  However, when the mechanical cutting and separating method is adopted, there is a problem that the glass cullet is unavoidably scattered from the glass cutting end face, no matter what care is taken.

  And once the scattered cullet adheres to the glass substrate, it cannot be easily removed in the cleaning process, so when adhering the sheet material to the glass surface, the adhered cullet must be removed manually. There is complexity. In addition, if a scriber or the like is used to remove cullet, the conductive film formed on the glass surface may be damaged.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a method of manufacturing a glass substrate for an electronic device that can efficiently manufacture a large number of finished glass substrates from a single glass base material. To do.

  In order to achieve the above object, a method for manufacturing a glass substrate for an electronic device according to the present invention is a first method in which a thin film layer is formed on one or both of the front and back surfaces of a glass substrate divided into a plurality of use regions. A second step of covering the entire glass substrate with a protective film so as to enclose the glass substrate after the step and the first step, and a plurality of uses of the glass substrate together with the protective film in a state covered with the protective film A third step of mechanically cutting and separating each region, a fourth step of peeling the protective film from each cut and separated glass substrate, and one or both of the front and back surfaces of the glass substrate from which the protective film has been peeled off And a fifth step of sticking the sheet material.

As the thin film layer, a conductive film can be preferably exemplified, and the glass substrate that has finished the first step preferably has translucency with a total light transmittance of 80% or more. Here, the conductive film is not particularly limited, but is preferably formed by applying a conductive polymer. And preferably, it should be comprised so that the resistivity of 300 ohms-3000 Mohm may be exhibited per unit area [cm < ² >] of an application surface. Moreover, the surface pencil hardness of the glass substrate which finished the 1st process should be B-6H. The lower the resistivity, the lower the hardness, and the higher the efficiency, the higher the hardness.

  Here, even if the conductive polymer is applied to the glass substrate, if the flatness of the glass substrate is high, sufficient adhesive strength cannot be exhibited. Therefore, preferably, prior to the first step, surface treatment for roughening the surface of the glass substrate on which the thin film layer is provided should be performed. As the surface treatment, it is preferable to bring the etching solution into contact with the glass surface, and it is simple to immerse the glass substrate in the etching solution in a state where the necessary portions of the glass substrate are sealed.

  In the case of forming a conductive thin film layer, it is conceivable that the conductive thin film layer is formed on both the front and back surfaces of the glass substrate from the antistatic application for protecting the electronic device. However, in consideration of manufacturing cost, it is preferable to form only on one side exposed to the user.

  In the second step of the present invention, the entire glass substrate is covered with a protective film. However, it is preferable not only to cover the glass substrate but also to adhere the protective film to the entire surface of the glass substrate. By adopting such a configuration, even if the glass substrate is mechanically cut in the subsequent third step, the glass cullet is not attached to the glass substrate, and only the protective film is peeled off in the fourth step. The cullet can be removed along with the protective film.

  The adhesive strength between the protective film and the glass substrate (more precisely, the thin film layer of the glass substrate) needs to be set optimally. According to the study of the present inventor, the 180 ° direction in the protective film application area of 25 mm × 25 mm In the peeling test (peeling speed 300 mm / min), it was found that the adhesive strength of the protective film should be set to 1.5 to 3.5 [N].

  Here, if the adhesive force is too strong, the thin film layer of the glass substrate is peeled off when the protective film is peeled off in the fourth step, whereas if the adhesive force is too weak, the glass substrate is cut and separated in the third step, A glass cullet etc. will adhere to a glass substrate because a protective film peels.

  Moreover, since it is necessary to cut | disconnect a protective film and a glass substrate at a stretch at a 3rd process, the film thickness of a protective film should be set to the range of 10-50 micrometers. In the third step, it is preferable to scan the glass surface by rotating the cutter blade of the rotary cutter to cut the protective film and the glass substrate. The contact pressure of the cutter blade should be maintained at a constant pressure based on the internal mechanism of the cutting device used in the third step, and this constant pressure is set to an optimum value within a range of 7N to 10N.

  In any case, the thickness of the protective film is set to 10 to 50 μm and the thickness of the glass substrate is set to 1.0 mm or less so that the glass substrate and the protective film can be easily cut at a pressure of about 7N to 10N. Is preferred.

  The glass substrate may be a single glass substrate or a bonded substrate obtained by bonding two glass substrates. As an example of the latter, a glass substrate constituting the display device can be exemplified, and a laminated glass substrate for a liquid crystal display suitably corresponds to this.

  And when manufacturing the glass substrate for liquid crystal displays, a polarizing sheet material is each affixed on each surface of two glass substrates in a 5th process. In this invention, since a glass cullet will be removed automatically when a protective film is peeled in a 4th process, a 5th process can be provided continuously from a 4th process.

  Although a cleaning process may be provided prior to the fourth process, wet cleaning immersed in the cleaning liquid is not necessary, and a dry cleaning process using an ion blower or ultrasonic cleaning is sufficient. As described above, in the present invention, since no wet cleaning is provided, a drying process is not required, and waste of processing time in the drying process and deterioration of the thin film layer in the drying process can be solved.

  According to the method for manufacturing a glass substrate for an electronic device of the present invention described above, a large number of completed glass substrates can be efficiently manufactured from one glass base material.

It is a flowchart explaining the manufacturing method which concerns on an Example. It is drawing explaining the manufacturing method of FIG.

  Hereinafter, the present invention will be described in detail based on examples. FIG. 1 is a flowchart illustrating a method for manufacturing a glass substrate for an electronic device according to an embodiment. In this embodiment, the laminated glass substrate is packed and transferred to another processing factory. As the glass substrate, a laminated glass substrate constituting a liquid crystal display is exemplified, but both are particularly limited. It is not something.

  Hereinafter, with reference to FIG. 1, in this embodiment, N × M liquid crystal displays are manufactured by processing the glass base material GL. That is, the glass base material GL to be processed is a laminated glass substrate GL in which display cells CEL... CEL of a liquid crystal display are formed vertically and horizontally. The laminated glass substrate GL includes N × M pieces of liquid crystal sealed between a first substrate G1 having a color filter on the inner surface side and a second substrate G2 having a transistor array disposed on the inner surface side. A display cell CEL is configured.

  The bonded glass substrate GL is immersed in an etching solution in a state where the peripheral edges of the first substrate G1 and the second substrate G2 are sealed, and the glass surface is chemically polished. As a result, the glass surface is appropriately roughened (ST1). In addition, the bonded glass substrate GL can be appropriately thinned by the chemical polishing treatment (ST1). The thickness of the laminated glass substrate GL provided for the coating treatment (ST2) is preferably 1.0 mm or less, and more preferably about 0.5 to 0.7 mm.

Next, the conductive polymer LAY is applied to the surface of the first glass substrate G1 using the slit coater for the bonded glass substrate GL that has been subjected to the cleaning of the glass substrate GL and the removal of the sealing material (ST2). : See FIG. 2 (a)). In this embodiment, a polythiophene-based conductive polymer is used, and the total light transmittance of the glass substrate G1 is set to have a light-transmitting property of 80% or more in the dry state after the dry drying process (ST3). . Moreover, per unit area [cm < ² >] of an application surface is set to the optimal resistivity of the range of 300 (ohm) -3000M (ohm) according to a use. Further, the surface pencil hardness of the glass substrate G1 in a dry state is set to be about B to 6H corresponding to the resistivity.

  Subsequently, the laminated glass substrate GL is laminated to cover the pair of protective films Fi1, Fi2 (ST4). The dry cleaning process (ST3) and the laminating process (ST4) are preferably performed in a clean room. Although the raw material of a protective film is not specifically limited, In this Example, what applied the acrylic adhesive to the polyester film is each affixed on the front and back of the bonding glass substrate GL.

  Here, although the adhesive force between the protective film and the glass substrate is a problem, it is a problem if it is too strong or too weak, and an adhesive layer that provides an optimum adhesive force is formed. Specifically, in the state where the protective film Fi1 is adhered to the glass substrate G1, the adhesive strength of the protective film in the 180 ° direction peeling test (peeling speed 300 mm / min) in the pasting area 25 mm × 25 mm of the protective film Fi1. Is set in the range of 1.5 to 3.5 [N / 25 mm].

  The film thickness of the protective films Fi1 and Fi2 is preferably as thin as possible without impairing workability and moisture resistance. Specifically, the film is preferably 50 μm or less, and preferably a film having a film thickness of 10 to 50 μm. Material is used. If the thickness is less than 10 μm, the sticking operation becomes difficult.

  In any case, when the sticking operation (ST4) is finished, a plurality of laminated glass substrates that have been laminated can be packed and shipped to another processing factory. That is, according to the present embodiment, the conductive film that is easily damaged is reliably protected, so that it is not necessary to finish all the processing processes in the same factory, which is also a great advantage. It goes without saying that consistent work at the same factory is not denied.

  Based on this point, the explanation here is based on the premise that the packing and shipping process is performed. However, in other processing factories that have finished receiving work, a plurality of laminated glass substrates GL,. , GL is taken out, and individual display cell regions CEL are cut out by forming scribe lines on the front and back sides of the individual laminated glass substrates GL (ST5 to ST6). FIG. 2B illustrates the scribe line CUT formed vertically and horizontally. After the first scribe line is formed on the first surface, the second scribe line is formed at the corresponding position on the second surface. Thus, the laminated glass substrate GL is cut together with the protective films Fi1 and Fi2.

  In this embodiment, since the glass substrate GL has a thickness of 1.0 mm or less and the protective films Fi1 and Fi2 have a thickness of 50 μm or less, the cutter blade of the rotary cutter is protected with a pressure of about 8N. Each display cell region CEL can be cut out by pressing the film Fi and scanning it.

  When the cutting and separating process is completed in this way, an ion blower process is executed (ST7). Here, the ion blower process removes static electricity that may have been charged on the protective film by blowing ions onto the workpiece CEL (each cut out laminated glass substrate) and removes foreign matters such as dust. It is a process to remove. It should be noted that a glass cullet is temporarily generated in the cutting and separating process, and the remaining glass cullet is merely attached to the protective film, so that no problem occurs.

  When the ion blower treatment is finished, the protective films Fi1 and Fi2 are subsequently peeled off (ST8). Although this peeling process is performed artificially, since the adhesive strength of the protective film Fi1 is set appropriately, it is not particularly difficult to work.

  And finally, if each polarizing sheet is stuck on the front and back surfaces of the work CEL, a liquid crystal display is completed (ST9).

  As mentioned above, although one Example of this invention was described concretely, the concrete description content does not specifically limit this invention.

ST2 First step ST4 Second step ST5 to ST6 Third step ST8 Fourth step ST9 Fifth step

Claims (11)

For a glass substrate divided into a plurality of use regions, a first step of forming a thin film layer on one or both of the front and back surfaces;
A second step of covering the entire glass substrate with a protective film so as to enclose the glass substrate after the first step;
A third step of mechanically cutting and separating the glass substrate together with the protective film for each of a plurality of use areas in a state covered with the protective film;
A fourth step of peeling the protective film from the individual glass substrates cut and separated;
About the glass substrate which peeled the protective film, The 5th process of sticking a sheet material on the one or both of the front and back surfaces, The manufacturing method of the glass substrate for electronic devices comprised.   The manufacturing method of Claim 1 which performs the surface treatment which makes an etching liquid contact the surface of the glass substrate which provides a thin film layer prior to a 1st process.   The manufacturing method according to claim 1 or 2, wherein in the first step, the conductive thin film layer is formed on one surface of the front and back surfaces of the glass substrate.   The manufacturing method according to claim 3, wherein the thin film layer is formed by applying a conductive polymer solution and has a resistivity of 300Ω to 3000 MΩ / □.   The surface pencil hardness of the glass substrate which finished the 1st process is B-6H, The manufacturing method in any one of Claims 1-4.   The manufacturing method according to claim 1, wherein the protective film is adhered to the glass substrate in the second step.   In a state where the protective film is adhered to the glass substrate, the adhesive strength of the protective film is 1.5 to 3.3 in a 180 ° peel test (peel rate 300 mm / min) in a protective film sticking area of 25 mm × 25 mm. The manufacturing method according to claim 5, which is 5 [N].   The manufacturing method according to claim 1, wherein the protective film has a film thickness of 10 to 50 μm.   The manufacturing method according to claim 1, wherein the glass substrate has a thickness of 1.0 mm or less.   The glass substrate is a liquid crystal glass substrate configured by laminating two glass substrates, and the sheet material is a polarizing film material and is adhered to the surfaces of the two glass substrates, respectively. The manufacturing method in any one of 1-9. The glass substrate which finished the 3rd process is a manufacturing method in any one of Claims 1-10 supplied to a 4th process through the dry cleaning process by an ion blower or ultrasonic cleaning.

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