CN111752017A - ITO pattern etching process for LCD production - Google Patents

ITO pattern etching process for LCD production Download PDF

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Publication number
CN111752017A
CN111752017A CN201910245745.7A CN201910245745A CN111752017A CN 111752017 A CN111752017 A CN 111752017A CN 201910245745 A CN201910245745 A CN 201910245745A CN 111752017 A CN111752017 A CN 111752017A
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glass
ito
treatment
photoresist
etching
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Chinese (zh)
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赵旭
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Hefei Precise Display Co ltd
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Hefei Precise Display Co ltd
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Priority to CN201910245745.7A priority Critical patent/CN111752017A/en
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    • GPHYSICS
    • G02OPTICS
    • G02FOPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/1303Apparatus specially adapted to the manufacture of LCDs
    • GPHYSICS
    • G03PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03FPHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
    • G03F7/00Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor

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  • Physics & Mathematics (AREA)
  • Nonlinear Science (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Optics & Photonics (AREA)
  • Surface Treatment Of Glass (AREA)
  • Liquid Crystal (AREA)
  • Photosensitive Polymer And Photoresist Processing (AREA)

Abstract

The invention relates to an LCD production process, and discloses an ITO pattern etching process for LCD production, which comprises the following process steps: the method comprises the following steps of ITO glass input, glass cleaning and drying treatment, photoresist coating treatment, pre-baking treatment, exposure treatment, developing treatment, film hardening treatment, etching treatment, film removing treatment and cleaning and drying treatment. The invention can be used in the production of LCD display screen, the pixel distance of the obtained product is shorter than that of the traditional LCD display screen, thereby obtaining large-area high-resolution liquid crystal display, and the contrast of the display panel is more extreme than that of the common product, the service life of the display panel is basically consistent with that of the common product, but the LCD display screen has simple processing technology and low production cost, can effectively control the heat dissipation capacity to the maximum extent, can directly integrate the corresponding functional module, has stronger later expandability, has better display effect of the obtained LCD display screen, and is worthy of popularization and use.

Description

ITO pattern etching process for LCD production
Technical Field
The invention relates to an LCD production process, in particular to an ITO pattern etching process for LCD production.
Background
The LCD is short for liquid crystal display, and is constructed by placing liquid crystal box between two parallel glass substrates, arranging TFT (thin film transistor) on the lower substrate glass, arranging color filter on the upper substrate glass, and controlling the rotation direction of liquid crystal molecules by changing signal and voltage on the TFT, so as to control whether polarized light of each pixel point is emitted or not to achieve the display purpose.
Now, LCDs have become the mainstream of replacements for CRTs, and the price has also dropped a lot and has become sufficiently popular.
Chinese patent (publication No. CN102708759) discloses a display screen processing technology, wherein the display screen comprises a display panel and a glass plate which is arranged on the outer side of the front face of the display panel and used for protecting the display panel, the display screen also comprises an optical film which is arranged between the display panel and the glass plate and is hermetically connected with the display panel and the glass plate through hot pressing treatment, the technology adopts the technical means of laminating the display panel and the glass plate and heating the optical film, so that the display panel and the glass plate are completely attached and sealed, but the technology does not design the step of a graph etching technology in the LCD production process, and the process step influences the final brightness, pixel point distribution and heat dissipation effect of the display screen.
Disclosure of Invention
The invention aims to provide an ITO pattern etching process for LCD production, which aims to solve the problems in the background technology.
In order to achieve the purpose, the invention provides the following technical scheme:
an ITO pattern etching process for LCD production comprises the following process steps:
(1) inputting ITO glass: selecting ITO glass to be loaded into a transfer basket;
(2) glass cleaning and drying treatment: cleaning the ITO glass obtained in the step (1) with a cleaning agent and deionized water, cleaning impurities and oil stains on the surface of the ITO glass, and finally taking out the ITO glass and drying the ITO glass;
(3) coating photoresist for treatment: uniformly coating a layer of photoresist on the surface of the conductive layer of the ITO glass obtained in the step (2);
(4) pre-baking treatment: drying the glass obtained in the step (3) for 10-15 min;
(5) and (3) exposure treatment: irradiating ultraviolet light on the surface of the glass photoresist obtained in the step (4) through a prefabricated spot pole pattern mask for 30-50 min;
(6) and (3) developing treatment: treating the glass surface obtained in the step (5) by using a developing solution, removing the photoresist layer decomposed by illumination, and reserving the photoresist of the unexposed part;
(7) hardening treatment: carrying out high-temperature treatment on the glass obtained in the step (6) at 200-250 ℃ for the second time;
(8) etching treatment: etching off the ITO film without the photoresist cover on the glass obtained in the step (7) by using an acid etching solution;
(9) and (3) stripping treatment: stripping the residual photoresist on the glass obtained in the step (8) by using a high-concentration stripping liquid;
(10) cleaning and drying: and (4) washing the glass obtained in the step (9) with high-purity water.
As a further scheme of the invention: in the step (1), the ITO layer faces upwards and is inserted into the basket.
As a still further scheme of the invention: in the step (4), the solvent in the photoresist needs to be completely volatilized.
As a still further scheme of the invention: and (5) covering a photoetching mask plate on the glass coated with the photoresist.
As a still further scheme of the invention: and (5) illuminating the adhesive under an ultraviolet lamp for selective exposure.
As a still further scheme of the invention: in the step (6), the part of the photoresist irradiated by the UV light is chemically dissolved in the developing solution.
As a still further scheme of the invention: in the step (9), an ITO pattern completely consistent with the pattern of the photoetching mask is required to be formed on the ITO glass.
As a still further scheme of the invention: in the step (10), the residual alkali liquor, the residual photoresist and other impurities on the glass need to be removed.
Compared with the prior art, the invention has the beneficial effects that:
the invention can be used in the production of LCD display screen, the pixel distance of the obtained product is shorter than that of the traditional LCD display screen, thereby obtaining large-area high-resolution liquid crystal display, and the contrast of the display panel is more extreme than that of the common product, the service life of the display panel is basically consistent with that of the common product, but the LCD display screen has simple processing technology and low production cost, can effectively control the heat dissipation capacity to the maximum extent, can directly integrate the corresponding functional module, has stronger later expandability, has better display effect of the obtained LCD display screen, and is worthy of popularization and use.
Drawings
FIG. 1 is a flow chart of a process for etching an ITO pattern produced by an LCD.
FIG. 2 is a schematic view of an ITO glass structure in an ITO pattern etching process for LCD production.
FIG. 3 is a schematic diagram of a photoresist structure on ITO glass in an ITO pattern etching process for LCD production.
FIG. 4 is a schematic diagram of the structure of an exposure step in an etching process of an ITO pattern produced by an LCD.
FIG. 5 is a schematic structural view of a development step in an ITO pattern etching process for LCD production.
FIG. 6 is a schematic diagram of the structure of an etching step in an etching process of an ITO pattern produced by an LCD.
FIG. 7 is a schematic diagram of the structure of an etching step in an etching process of an ITO pattern produced by an LCD.
Detailed Description
The technical solution of the present patent will be described in further detail with reference to the following embodiments.
Example one
Referring to fig. 1-7, an etching process of ITO pattern for LCD production includes the following steps:
(1) inputting ITO glass: selecting ITO glass to be loaded into a transfer basket tool, and inserting the ITO layer into the basket tool with the ITO layer facing upwards;
(2) glass cleaning and drying treatment: cleaning the ITO glass obtained in the step (1) with a cleaning agent and deionized water, cleaning impurities and oil stains on the surface of the ITO glass, and finally taking out the ITO glass and drying the ITO glass;
(3) coating photoresist for treatment: uniformly coating a layer of photoresist on the surface of the conductive layer of the ITO glass obtained in the step (2);
(4) pre-baking treatment: drying the glass obtained in the step (3) for 10min, wherein the solvent in the photoresist needs to be completely volatilized, so that the adhesion with the surface of the glass is increased;
(5) and (3) exposure treatment: irradiating ultraviolet light on the surface of the glass photoresist obtained in the step (4) through a prefabricated dot pole pattern mask for 30min, covering a photoetching mask on the glass coated with the photoresist, and selectively exposing the photoresist under an ultraviolet lamp;
(6) and (3) developing treatment: treating the glass surface obtained in the step (5) with a developing solution, removing the photoresist layer decomposed by illumination, reserving the photoresist of the unexposed part, and chemically dissolving the photoresist of the part irradiated by the UV light in the developing solution;
(7) hardening treatment: carrying out high-temperature treatment on the glass obtained in the step (6) at 200 ℃;
(8) etching treatment: etching off the ITO film without the photoresist cover on the glass obtained in the step (7) by using an acid etching solution;
(9) and (3) stripping treatment: stripping the residual photoresist on the glass obtained in the step (8) by using a high-concentration stripping liquid, and forming an ITO pattern which is completely consistent with the pattern of the photoetching mask on the ITO glass;
(10) cleaning and drying: and (4) washing the glass obtained in the step (9) with high-purity water, wherein residual alkali liquor, residual photoresist and other impurities on the glass need to be removed completely.
Example two
Referring to fig. 1-7, an etching process of ITO pattern for LCD production includes the following steps:
(1) inputting ITO glass: selecting ITO glass to be loaded into a transfer basket tool, and inserting the ITO layer into the basket tool with the ITO layer facing upwards;
(2) glass cleaning and drying treatment: cleaning the ITO glass obtained in the step (1) with a cleaning agent and deionized water, cleaning impurities and oil stains on the surface of the ITO glass, and finally taking out the ITO glass and drying the ITO glass;
(3) coating photoresist for treatment: uniformly coating a layer of photoresist on the surface of the conductive layer of the ITO glass obtained in the step (2);
(4) pre-baking treatment: drying the glass obtained in the step (3) for 12min, wherein the solvent in the photoresist needs to be completely volatilized, so that the adhesion with the surface of the glass is increased;
(5) and (3) exposure treatment: irradiating ultraviolet light on the surface of the glass photoresist obtained in the step (4) through a prefabricated dot pole pattern mask for 40min, covering a photoetching mask on the glass coated with the photoresist, and selectively exposing the photoresist under an ultraviolet lamp;
(6) and (3) developing treatment: treating the glass surface obtained in the step (5) with a developing solution, removing the photoresist layer decomposed by illumination, reserving the photoresist of the unexposed part, and chemically dissolving the photoresist of the part irradiated by the UV light in the developing solution;
(7) hardening treatment: carrying out high-temperature treatment on the glass obtained in the step (6) at 225 ℃;
(8) etching treatment: etching off the ITO film without the photoresist cover on the glass obtained in the step (7) by using an acid etching solution;
(9) and (3) stripping treatment: stripping the residual photoresist on the glass obtained in the step (8) by using a high-concentration stripping liquid, and forming an ITO pattern which is completely consistent with the pattern of the photoetching mask on the ITO glass;
(10) cleaning and drying: and (4) washing the glass obtained in the step (9) with high-purity water, wherein residual alkali liquor, residual photoresist and other impurities on the glass need to be removed completely.
EXAMPLE III
Referring to fig. 1-7, an etching process of ITO pattern for LCD production includes the following steps:
(1) inputting ITO glass: selecting ITO glass to be loaded into a transfer basket tool, and inserting the ITO layer into the basket tool with the ITO layer facing upwards;
(2) glass cleaning and drying treatment: cleaning the ITO glass obtained in the step (1) with a cleaning agent and deionized water, cleaning impurities and oil stains on the surface of the ITO glass, and finally taking out the ITO glass and drying the ITO glass;
(3) coating photoresist for treatment: uniformly coating a layer of photoresist on the surface of the conductive layer of the ITO glass obtained in the step (2);
(4) pre-baking treatment: drying the glass obtained in the step (3) for 15min, wherein the solvent in the photoresist needs to be completely volatilized, so that the adhesion with the surface of the glass is increased;
(5) and (3) exposure treatment: irradiating ultraviolet light on the surface of the glass photoresist obtained in the step (4) through a prefabricated dot pole pattern mask for 50min, covering a photoetching mask on the glass coated with the photoresist, and selectively exposing the photoresist under an ultraviolet lamp;
(6) and (3) developing treatment: treating the glass surface obtained in the step (5) with a developing solution, removing the photoresist layer decomposed by illumination, reserving the photoresist of the unexposed part, and chemically dissolving the photoresist of the part irradiated by the UV light in the developing solution;
(7) hardening treatment: carrying out high-temperature treatment on the glass obtained in the step (6) at 250 ℃;
(8) etching treatment: etching off the ITO film without the photoresist cover on the glass obtained in the step (7) by using an acid etching solution;
(9) and (3) stripping treatment: stripping the residual photoresist on the glass obtained in the step (8) by using a high-concentration stripping liquid, and forming an ITO pattern which is completely consistent with the pattern of the photoetching mask on the ITO glass;
(10) cleaning and drying: and (4) washing the glass obtained in the step (9) with high-purity water, wherein residual alkali liquor, residual photoresist and other impurities on the glass need to be removed completely.
Although the preferred embodiments of the present patent have been described in detail, the present patent is not limited to the above embodiments, and various changes can be made without departing from the spirit of the present patent within the knowledge of those skilled in the art.

Claims (8)

1. An ITO pattern etching process for LCD production is characterized by comprising the following process steps:
(1) inputting ITO glass: selecting ITO glass to be loaded into a transfer basket;
(2) glass cleaning and drying treatment: cleaning the ITO glass obtained in the step (1) with a cleaning agent and deionized water, cleaning impurities and oil stains on the surface of the ITO glass, and finally taking out the ITO glass and drying the ITO glass;
(3) coating photoresist for treatment: uniformly coating a layer of photoresist on the surface of the conductive layer of the ITO glass obtained in the step (2);
(4) pre-baking treatment: drying the glass obtained in the step (3) for 10-15 min;
(5) and (3) exposure treatment: irradiating ultraviolet light on the surface of the glass photoresist obtained in the step (4) through a prefabricated spot pole pattern mask for 30-50 min;
(6) and (3) developing treatment: treating the glass surface obtained in the step (5) by using a developing solution, removing the photoresist layer decomposed by illumination, and reserving the photoresist of the unexposed part;
(7) hardening treatment: carrying out high-temperature treatment on the glass obtained in the step (6) at 200-250 ℃ for the second time;
(8) etching treatment: etching off the ITO film without the photoresist cover on the glass obtained in the step (7) by using an acid etching solution;
(9) and (3) stripping treatment: stripping the residual photoresist on the glass obtained in the step (8) by using a high-concentration stripping liquid;
(10) cleaning and drying: and (4) washing the glass obtained in the step (9) with high-purity water.
2. The process of claim 1, wherein in step (1), the ITO layer is inserted into the basket in an upward direction.
3. The etching process for etching ITO pattern of LCD according to claim 1, wherein in step (4), the solvent in the photoresist needs to be completely volatilized.
4. The etching process of ITO pattern for LCD production according to claim 1, wherein in step (5), a photo-etching mask is coated on the glass coated with photoresist.
5. The etching process for ITO patterns produced by LCD according to claim 1 or 4, wherein in step (5), the photoresist is selectively exposed under an ultraviolet lamp.
6. An etching process of ITO pattern for LCD production according to claim 1, wherein in said step (6), the photo-etching solution of the portion irradiated by UV light is chemically dissolved in the developing solution.
7. The etching process of the ITO pattern produced by LCD according to claim 1, wherein in step (9), an ITO pattern completely consistent with the pattern of the photolithographic mask is formed on the ITO glass.
8. The etching process of ITO pattern produced by LCD according to claim 1, wherein in step (10), the residual alkali solution, residual photoresist and other impurities on the glass need to be removed.
CN201910245745.7A 2019-03-28 2019-03-28 ITO pattern etching process for LCD production Pending CN111752017A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114236889A (en) * 2021-12-27 2022-03-25 安徽金视界光电科技有限公司 Preparation method of LCD
CN116540438A (en) * 2023-04-25 2023-08-04 苏州润博希电子科技有限公司 LCD display screen processing method
CN117250783A (en) * 2023-10-26 2023-12-19 湖北欧雷登显示科技有限公司 Integrated forming production process and application of liquid crystal display module

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US20150085219A1 (en) * 2013-09-24 2015-03-26 Shenzhen China Star Optoelectronics Technology Co., Ltd. TFT-LCD Array Substrate Manufacturing Method and LCD Panel/Device Produced by the Same
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CN107329378A (en) * 2017-09-01 2017-11-07 东莞通华液晶有限公司 A kind of high-precision ITO photoetching processes
CN108037644A (en) * 2017-12-29 2018-05-15 河源市力友显示技术有限公司 A kind of ultra-thin ito glass production line and production method
CN109445139A (en) * 2018-12-26 2019-03-08 山水电子(中国)有限公司 A kind of manufacturing process of novel liquid crystal display screen

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US20150085219A1 (en) * 2013-09-24 2015-03-26 Shenzhen China Star Optoelectronics Technology Co., Ltd. TFT-LCD Array Substrate Manufacturing Method and LCD Panel/Device Produced by the Same
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CN106773561A (en) * 2016-12-09 2017-05-31 曾周 A kind of etch process of LCD productions
CN106980199A (en) * 2017-03-14 2017-07-25 上海金硙电子有限公司 A kind of transparent display and its manufacturing process
CN107329378A (en) * 2017-09-01 2017-11-07 东莞通华液晶有限公司 A kind of high-precision ITO photoetching processes
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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114236889A (en) * 2021-12-27 2022-03-25 安徽金视界光电科技有限公司 Preparation method of LCD
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CN116540438A (en) * 2023-04-25 2023-08-04 苏州润博希电子科技有限公司 LCD display screen processing method
CN116540438B (en) * 2023-04-25 2023-10-27 苏州润博希电子科技有限公司 LCD display screen processing method
CN117250783A (en) * 2023-10-26 2023-12-19 湖北欧雷登显示科技有限公司 Integrated forming production process and application of liquid crystal display module
CN117250783B (en) * 2023-10-26 2024-06-11 湖北欧雷登显示科技有限公司 Integrated forming production process and application of liquid crystal display module

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