JP2000340106A - Manufacture of substrate for plasma display panel and forming die used therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a substrate for a PDP and a forming die therefor, allowing the forming die to be repeatedly used while preventing a base body and ribs from being damaged, and further to provide a manufacturing method of the substrate for a PDP dispensing with a removal process of a rib molding or precursor in peripheral parts of the base body. SOLUTION: This manufacturing method for a plasma display panel substrate installs ribs on a base body. A rib precursor, including a first photo-curing initiator with a first absorption edge and a first photo-curing constituent, is stuck fast to the base body, and a second photo-curing constituent is photo-cured in the existence of a second photo-curing initiator with a second adsorption edge of a wavelength shorter than the wavelength corresponding to the first absorption edge of the first photo-curing initiator. A forming die so obtained is filled with the rib precursor, the rib precursor is cured by being irradiated with light of a wavelength shorter than the wavelength corresponding to the second absorption edge, and the forming die is removed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for manufacturing a substrate for a plasma display panel (hereinafter, also simply referred to as "PDP") and a mold used therefor.

[0002]

2. Description of the Related Art PDPs are expected as thin large-screen display devices. Generally, a PDP includes a so-called PDP substrate. In a typical PDP substrate, a pair of glass flat plates are configured to face each other via a rib having a predetermined dimension (also referred to as a barrier rib, a partition, or a barrier).
In this case, such ribs hermetically partition the space between the pair of glass plates to define a plurality of discharge display cells for accommodating a discharge gas such as neon, helium or xenon.

Various methods have been proposed for producing and arranging ribs. For example, a method using a molding die is known.
In general, according to this method, a liquid molded product filled in a molding die is converted into a rib molded product that can be transferred to a flat substrate by a thermal or optical action. Also, at the same time that the mold is removed from the ribs, the production and placement of the ribs can be performed substantially continuously with relatively high accuracy.

In a general PDP substrate, a base or rib made of glass or ceramic is used.
On the other hand, a typical mold for a PDP substrate is made of metal, glass or ceramic as disclosed in Japanese Patent Application Laid-Open No. 9-12336, for example. Therefore, the base and the rib have a hardness equal to or less than that of the mold, and as a result, when the mold is removed from the rib, the base or the rib may be damaged, or the mold itself may be damaged. Or Such damage is described in Japanese Patent Application Laid-Open No. 9-2830.
As disclosed in Japanese Patent Publication No. 17-174, it is remarkable when a rib is formed by pressing using a mold made of glass, ceramic or metal. The mold is used repeatedly for mass production. It is not preferable to leave broken ribs in the mold. This is because the mold needs to be cleaned every time the ribs are manufactured, which reduces productivity.

Japanese Patent Application Laid-Open No. 9-134676 also discloses the use of a mold made of a silicone resin having a lower hardness than glass or ceramic. However, silicone resins are generally brittle. Therefore, it cannot be expected that a mold made of a silicone resin will be repeatedly used for mass production.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method of manufacturing a PDP substrate in which a mold can be repeatedly used while avoiding breakage of a substrate or a rib, and
An object of the present invention is to provide a molding die for use in the method.

[0007]

According to the present invention, a step of adhering a rib precursor composition containing a first photocurable initiator having a first absorption edge and a first photocurable component to a substrate, Photocuring the second photocurable component in the presence of a second photocuring initiator having a second absorption edge with a shorter wavelength than the wavelength corresponding to the first absorption edge of the first photocuring initiator A step of filling the rib precursor composition into the molding die obtained by allowing the rib precursor composition to be irradiated with light having a wavelength longer than the wavelength corresponding to the second absorption edge. Curing the rib precursor composition to form a rib on a substrate, and removing the mold from the resulting rib-formed substrate rib.
A method for manufacturing a substrate for a plasma display panel is provided. Either the step of bringing the rib precursor composition into close contact with the substrate or the step of filling the rib precursor composition may be performed first. That is, the rib precursor composition may be filled in the mold, and thereafter, they may be brought into close contact with the substrate.

According to the present invention, there is provided a rib precursor composition comprising a substrate, a first photocuring initiator having a first absorption end provided on the substrate, and a first photocurable component. A mold for a plasma display panel substrate comprising: a formed rib, wherein the mold has a shorter wavelength than a wavelength corresponding to the first absorption edge of the first photocuring initiator. A mold obtained by photo-curing the second photo-curable component in the presence of a second photo-curing initiator having an absorption edge of

Further, in the above method, light having a wavelength shorter than the wavelength corresponding to the second absorption edge is irradiated to the rib precursor composition filled in the mold at the peripheral portion of the base, and the rib precursor is irradiated with the light. A manufacturing method is provided, further comprising a step of curing the precursor composition. According to such a method,
As described in detail below, the rib molded body is fixed to the mold by a light curing reaction between the unreacted second curable component in the mold and the first curable component in the rib precursor composition. Thus, in the step of removing the forming die, the rib forming body at the peripheral edge of the base is removed integrally with the forming die, so that the step of removing the rib forming body at the peripheral part of the base is not required.

As used herein, the term “absorption edge”
Is a wavelength portion in a continuous absorption spectrum of light, in which the absorptance decreases sharply as the wavelength becomes longer, and changes to substantially transparent.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in accordance with embodiments, but it is easily understood by those skilled in the art that the present invention is not limited thereto. In the drawings, the same or corresponding portions are denoted by the same reference numerals.

FIG. 1 is a partially exploded perspective view showing a PD of the present invention.
One embodiment of a P substrate is schematically illustrated. The illustrated PDP substrate 10 is used for a so-called AC type PDP, but is not limited to this, and can be applied to a DC type PDP substrate. The PDP substrate 10 is provided with transparent and opposed flat plates, preferably made of soda lime glass, which are easily available. A plurality of ribs 16 having a predetermined size are provided between the back plate 12 and the front plate 14 so as to partition a space between them so that a plurality of discharge display cells 18 can be defined. Has become.

The illustrated ribs 16 are formed from a photosensitive paste (rib precursor composition) 32. Desirable photosensitive pastes include a first photocurable component as a binder component, a photocurable initiator having a first absorption edge, a ceramic powder, and optionally a glass powder. The ceramic powder is used to give a certain shape to the ribs, and is preferably made of alumina, silica, titania or walnite (wollastonite) having high strength.

The first photocurable component is photopolymerized in the presence of a first photocuring initiator having a first absorption edge, and the ribs 16
Can be maintained. The first photocurable component is not particularly limited, but an acrylic resin is preferred. The acrylic resin is formed from, for example, an acrylic monomer or oligomer or a silane coupling agent having a methacryl group. In particular, as the acrylic monomer or oligomer, HEMA (hydroxyethyl methacrylate), HEA (hydroxyethyl acrylate),
Monomers or oligomers such as BisGMA (bisphenol A diglycidyl ether methacryl oxide) and triethylene glycol dimethacrylate are preferably used.

In particular, when the first photocurable component is a silane coupling agent having a methacrylic group, a network structure is formed by photopolymerization of the methacrylic group, so that the ceramic powder can be accommodated and held. it can. In addition, the first photocurable component of the silane coupling agent generates high molecular weight silicon dioxide having a high melting point by firing. This network structure formed by the silane coupling agent is substantially maintained at a relatively high temperature by the silicon dioxide even after the sintering, so that the ceramic powder or the glass powder can be retained. Such a silane coupling agent is preferably γ-methacryloxypropylmethyltrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropyltriethoxysilane having a molecular weight of 232 to 290 in consideration of availability. It is preferably silane or γ-methacryloxypropylmethyldiethoxysilane.

Glass powder is used to give a rib a dense structure to increase its strength. Basically, the glass powder need only fill the small gaps between the network of silicon dioxide and the ceramic powder surrounded by it. In the absence of a network structure, the glass powder does not need to fill large gaps between the ceramic powders. as a result,
A relatively small amount of glass powder can increase the strength of the rib. Even if the glass powder mainly contains lead having a high mass absorption coefficient, it hardly affects the photocuring speed. Further, the use of glass powder made of expensive low-melting glass can be suppressed. Basically, the glass powder is 10 to 70% by volume based on the volume of the rib precursor composition.
include. Preferably the glass powder is 20-50% by volume
Included to further increase the strength of the ribs.

Further, when the network structure receives heat together with the glass powder, the network structure is maintained as long as the melting point of the silicon dioxide constituting the network is not reached, and the volume does not substantially change. Even if there is a change in volume, it is slight.

The front plate 14 or the rear plate 12 is, for example, 550
When it is made of glass having a slow cooling point of ° C., it is desirable that the glass powder has a lower softening point of 450 to 550 ° C. The glass powder having such a softening point is heated together with the front plate or the back plate of the glass and flows into the gap, so that even if the powder enters the gap,
2 can be prevented from being thermally deformed. As the glass powder has the above softening point, basically, lead glass containing a predetermined amount of boron, zinc, phosphoric acid, lead, titanium or a combination thereof, aluminum phosphate glass,
It is made of boron titanium glass, bismuth glass or zinc glass. In order to reduce the photocuring time of the rib precursor composition without considering a high mass absorption coefficient,
Preferably, it contains boron, zinc, phosphoric acid or or titanium or a combination thereof. At this time, their respective compositions are not particularly limited. However, the glass powder preferably has a softening point higher than the firing temperature of the first curable component. When the glass powder having such a softening point is used, the glass powder does not dissolve before the removal of the first curable component by firing, so that the glass component surrounds the first curable component. Thus, the possibility that the first curable component remains can be avoided.

The photosensitive paste 32 may contain an oxidation catalyst if necessary. Usually, the oxidation catalyst is chromium (C
r), manganese (Mn), iron (Fe), cobalt (Co), nickel (N
i), copper (Cu), zinc (Zn), indium (In) or tin (Sn), ruthenium (Ru), rhodium (Rh), palladium (Pd), silver (A
g), an oxide, salt or complex of iridium (Ir), platinum (Pt), gold (Au) or cerium (Ce), which can reduce the energy required for firing the first photocurable component. . Specifically, the firing temperature is reduced from about 500-550 ° C. by 50-90 ° C. so that the first photocurable component causing outgassing undesired for plasma discharge is completely removed from the ribs at relatively low temperatures. Can be removed. In particular, when it is required that the glass powder has a softening point higher than the firing temperature of the first photocurable component as described above, the firing temperature is lowered by using an oxidation catalyst, thereby reducing the glass powder. The required minimum softening point of the body is reduced, and consequently the choice of glass components is increased.

Further, such a reduction in the firing temperature can effectively suppress the thermal deformation (for example, warping, bending or shrinkage) of the glass plate. For example, 5mm width and 2.8m
137 g when a glass slab having a thickness of m 2 is formed by readily available soda-lime glass.
At 550 ° C. and 500 ° C.
While bending by 5 μm and 5 μm respectively, 46
It is known that it hardly bends at 0 ° C. The isotropic thermal shrinkage of the glass plate is 550 ° C., 5 ° C.
At 00 ° C and 460 ° C, 400 ppm,
It is also known to be 225 ppm and 125 ppm. On the other hand, when the above-mentioned glass plate is formed of high strain point glass commercially available from Asahi Glass Co., Ltd. under the trade name PD200, at 200, 75 and 30 ppm at 550 ° C., 500 ° C. and 460 ° C., respectively.
It is also well known that heat contraction isotropically by pm. In the absence of an oxidation catalyst, the first photocurable component can be removed at a firing temperature of at least about 500 ° C. or higher,
When the calcination temperature is reduced by 50-90 ° C. by the oxidation catalyst as described above, such deflection and thermal shrinkage are reduced.

Each discharge display cell 18 has an address electrode 2
0 is arranged on the back plate 12 along the rib 16,
A transparent bus electrode 22 made of indium tin oxide (ITO) is disposed on the front plate 14 perpendicular to the rib 16. Further, a discharge gas such as neon, helium, or xenon can be accommodated between the address electrode 20 and the bus electrode 22 to enable light emission by discharge. A fluorescent layer 24 may be provided on each address electrode 20 in a predetermined order to enable color display. Further, a transparent dielectric layer 26 is provided on the front plate 14 and the bus electrode 22 to cover the bus electrode 22, and the PDP is formed by suppressing sputtering of the bus electrode 22.
May be extended.

Next, the formation and installation of the ribs will be described in detail with reference to the cross-sectional views of the steps of manufacturing the PDP substrate shown in FIG.

First, a mold 30 having a concave portion 28 corresponding to the shape of a rib is prepared (see FIG. 2A). Although not shown, the concave portion 28 may have a trapezoidal cross section.
Although not shown, a release agent may be applied to the surface of the concave portion to impart release properties to the mold.

The molding die 30 can be obtained by photo-curing the second photo-curable component in the presence of a second photo-curing initiator having a second absorption edge. An acrylic monomer or oligomer can be used as the second photocurable component. In particular, as the acrylic monomer or oligomer, Henkel's “Photomer 601”
An aliphatic urethane acrylate commercially available under the trade name of "0", for example, 1,6 hexanediol diacrylate commercially available from Shin-Nakamura Chemical is suitably used. Since the molding die is molded by photopolymerization, it is not necessary to perform a cutting process each time the molding die 30 is manufactured. In addition, since photopolymerization proceeds relatively quickly, the mold 30 can be easily obtained in a short time.

Further, such a mold 30 has a lower hardness than general glass or ceramics, and can prevent breakage of the ribs and the base when the mold is removed from the substrate. As a result, the mold is repeatedly used without being washed.

As described above, the photopolymerization of the second photocurable component is carried out by the second light having a second absorption edge having a shorter wavelength than the wavelength corresponding to the first absorption edge of the first photocuring initiator. Performed in the presence of a curing initiator. Such a second photocuring initiator cannot absorb light having a wavelength longer than the wavelength corresponding to the second absorption edge. In contrast, the first photo-curing initiator can absorb such light. As a result, when the rib precursor composition is cured with light having a wavelength longer than the wavelength corresponding to the second absorption edge, even if the unreacted second photocurable component remains in the mold 30. Also, it can be avoided that only the first photocurable component is photopolymerized and cured, and the second photocurable component is further photopolymerized at the same time. Preferred photocuring initiators are aminoketone (400 to 430 nm), bisacylphosphine oxide (440 nm), camphorquinone (500
nm), metallocene hydroxyketone (500 nm) and benzyl dimethyl ketal (380 nm), which are available from Ciba-Geigy, Inc. (380nm)
, Irgacure 651 (390 nm), Irgacure 907
(400 nm), Irgacure 149 (420 nm), Irgacure 1700 (440 nm), Irgacure 1850 (440 nm), Irgacure 819 (450 nm), Irgacure 369 (480 n
m) and Irgacure 784 (500 nm). According to the present invention, the determination of the first photo-curing initiator and the second photo-curing initiator is performed by appropriately selecting two types of photo-curing initiators having different absorption edges as exemplified above. For example, the combination of the first photo-curing initiator and the second curing photo-initiator includes Darocure 1173 having an absorption edge corresponding to a wavelength of 380 nm, Irgacure 819 having an absorption edge corresponding to a wavelength of 440 to 450 nm, and Irgacure 170.
0 and Irgacure 1850.

Next, the photosensitive paste 32 is applied to the mold 30 while filling the recesses 28 (see FIG. 2B). 1 × 10 ³ to 1 × 10 ⁵ cps for photosensitive paste 32
It is preferable that the viscosity is given. This is because by having such a viscosity, the photosensitive paste can be filled with high accuracy. For adjusting the viscosity of the paste, a surfactant may be added. Preferred surfactants are lauryl betaine, polyoxyethylene sorbitan monolaurate, polyoxyethylene octyl phenyl ether, polyoxyethylene nonyl phenyl ether, phosphate alkyl polyol, which are respectively Ambitol 24B and Rheodol TW- from Kao Corporation. L-106, Emulgen 840S, Emulgen 909,
And sold by Imation under the trade name POCAII.

The photosensitive paste containing a silane coupling agent as the first photocurable component contains a mineral acid such as hydrochloric acid or nitric acid and hydrolyzes the silane coupling agent to form a sol photosensitive paste. May be provided. Such a photosensitive paste can disperse ceramic powder and glass powder without gelling even when dried. Also, the viscosity does not depend on the amount of water.

Thereafter, the back plate 12 is coated with the photosensitive paste 32.
(See FIG. 2 (C)). The above-mentioned second photocurable component can impart flexibility to the mold 30 by photopolymerization. In such a case, the photosensitive paste 32 can be contacted from one end of the back plate 12 by bending the mold 30. Therefore, the air between the back plate 12 and the photosensitive paste 32 is efficiently removed to the outside, and the intrusion of air into the photosensitive paste 32 is also avoided. Alternatively, the photosensitive paste 32 may be applied to the back plate 12 first, and then may be bonded while bending the mold 30 so that the photosensitive paste 32 is filled between the concave portion 28 and the back plate 12. Also in this case, the air is efficiently removed to the outside, and the intrusion of the air into the photosensitive paste 32 is also avoided. Further, an antifoaming agent can be added to prevent rib defects due to bubbles. Examples of the antifoaming agent include Dappo SN series manufactured by San Nopco. The defoamer is 1 to 5 based on the weight of the first curable component.
% Can be used.

Next, a light ray (hν) having a wavelength longer than the second absorption edge of the second photocuring initiator is applied to the photosensitive paste 32.
To polymerize the first photo-curable component to form a rib molding 3
4 (see FIG. 2C). In this case, the polymerization is basically carried out only by light, and heat management which is difficult to control is basically unnecessary. In addition, the second photocurable component of the present embodiment can also impart transparency to the mold 30 when photopolymerized. When the mold 30 is transparent, alignment of the mold 30 on the back plate 12 is easy. Irradiation of the light beam to the photosensitive paste 32 can be performed not only via the back plate 12 but also from both sides simultaneously via the mold 30. As a result, the light beam can sufficiently reach the first photocurable initiator and the first photocurable component located deep in the concave portion 28, and the unreacted first photocurable component can Will not remain. The molded body 34 is given substantially uniform mechanical strength.

In order to form ribs without defects, sufficient light intensity is required. If the light intensity is low, the cured molded body 34 cracks during the firing process. For example, when Philips 40 W straight tube fluorescent lamps are arranged on a plane at an interval of 7 cm, at least 3 mm from the plane.
It is necessary to arrange the back plate 12 at a distance shorter than 0 cm and irradiate light. The ribs 16 formed by irradiating light at a longer distance than this will show many cracks after firing.

The amount of the first photo-curing initiator is also an important condition for forming ribs without defects. If the amount of the first curing initiator is too small, the molded body 34 cracks during the firing process. The amount of the first photocuring initiator is 0.1% or more, preferably 0.5%, based on the weight of the first curable component.
% Or more.

The irradiated light beam has a relatively long wavelength, is absorbed only by the first photocuring initiator, is not substantially absorbed by the second photocuring initiator, and Only the polymerization is started to obtain a molded body 34. As a result, even if the unreacted second photocurable component remains in the mold 30, it can be suppressed from reacting with the first photocurable component. That is, the molding 34 is formed by photopolymerization.
Sticking to zero can be avoided.

Next, the molded body 34 is removed from the molding die 30, and the molded body 34 is integrally transferred to the back plate 12 (see FIG. 2D). As described above, the fixation of the molded body 34 to the molding die 30 is avoided. Therefore, the rear plate 12 or the molded body 34 or the free end thereof is not damaged and remains in the molding die 30, and such removal can be easily performed. As a result, the mold 3
0 can be used repeatedly without being cleaned, and the productivity of the PDP substrate can be improved.

Then, the molded body 34 is placed together with the back plate 12 in a firing furnace (not shown), and fired at a predetermined temperature to obtain the ribs 16 (see FIG. 2E). Before and after the firing, the above-mentioned network structure is substantially maintained, and the shrinkage of the molded body is reduced. Therefore, a rib according to the shape of the concave portion can be accurately manufactured.

If necessary, an address electrode may be formed between the ribs on the back plate, and a fluorescent layer may be provided on the address electrode. Thereafter, a transparent front plate on which bus electrodes are formed in advance may be arranged via a rib so as to face the rear plate. Next, the peripheral edges of the front plate and the back plate may be hermetically sealed using a sealing material (not shown) to form a discharge display cell between the front plate and the back plate. Then, after the discharge display cell is evacuated to a reduced pressure, a discharge gas may be introduced into the discharge cell to produce a PDP substrate.

When the address electrodes are formed between the ribs on the rear plate, the pitch of the address electrodes on the rear plate must match the pitch of the concave portions for forming the ribs of the mold. The coefficient of thermal expansion of the mold 30 of the present invention is generally 1.5 × 10
^{−5 to} 3.5 × 10 ⁻⁵ / ° C., while the coefficient of thermal expansion of the back plate is generally 0.8 × 10 ^{−5 to} 0.9 × 10 ⁻⁵ / ° C. For this reason, when the two pitches are different at room temperature, the two pitches can be matched by controlling the temperature using the difference in the coefficient of thermal expansion between the two.

FIG. 3 is a process sectional view showing a second embodiment of the method for manufacturing a PDP substrate of the present invention. In the figure, the details of the rib forming recesses on the mold 30 are omitted.
According to the present embodiment, before irradiating the rib precursor composition 32 with light having a wavelength longer than the wavelength corresponding to the second absorption edge, the rib 16 is turned on as shown by an arrow in FIG. Light (hν ₁ ) having a shorter wavelength than the wavelength corresponding to the second absorption edge is irradiated on the rib precursor composition 32 filled in the peripheral portion of the back plate 12 which is not required. According to the present embodiment, the rib molding 34 adheres to the molding die 30 by the photocuring reaction between the unreacted second curing component in the molding die 30 and the first curing component in the rib precursor composition 32. , Thereby forming the mold 3
In the step of removing 0, the rib molded body 34 at the peripheral edge of the back plate 12 is removed integrally with the molding die 30, so that the step of removing the rib molded body 34 at the peripheral edge of the back plate 12 is not required. The light irradiation is desirably performed from the mold 30 side. This is because, when the process is performed from the back plate 12 side, the rib molded body 34 may adhere not only to the mold 30 but also to the back plate 12. For light irradiation, if necessary, a light-shielding mask 40 may be used to prevent light irradiation on the central portion of the mold 30.

As described above, when the unreacted second photocurable component remains at the peripheral portion of the mold 30, the irradiation of the light (hν ₁ ) causes the second photocuring initiator to react with the second photocurable component. In order to absorb light, a curing reaction between the second curable component in the mold 30 and the first photocurable component in the rib precursor composition 32 is caused. That is, at the peripheral portion of the back plate 12 irradiated with such light (hν ₁ ), the molded body 34 and the molding die 30 are fixed at the peripheral portion by photopolymerization.
For this reason, the rib molding 34 filled in the peripheral portion of the back plate 12 can be easily removed from the back plate 12 integrally with the molding die 30. In order to prevent the light irradiated through the mold 30 from being reflected on the back plate 12 and irradiating the rib precursor composition 32 from the back plate 12 side, the back plate 1
A paint and a film that absorb such light (hν ₁ ) may be attached to the back surface of 2.

Subsequently, light (h) having a wavelength longer than the wavelength corresponding to the second absorption edge is applied to the rib precursor composition 32 filled in the center of the back plate 12 where the rib 16 is required.
ν ₂ ) is subsequently irradiated as shown in FIG. The mold 30 is provided with transparency by photopolymerization of a photo-curing component, and enables irradiation of light to the rib precursor composition 32 from both sides not only through the back plate 12 but also through the mold 30. I do. As a result, the light beam can sufficiently reach the first curable component and the first photocuring initiator deep in the concave portion 28, and the molded body 34 is provided with substantially uniform mechanical strength. You.

The preferred light beam to be irradiated has a relatively long wavelength, is absorbed only by the first photo-curing initiator in the rib precursor composition 32, and is irradiated by the second photo-curing initiator of the mold 30. Is preferably not substantially absorbed. In this case, even if the unreacted second curable component remains in the mold 30, it does not react with the first curable component in the rib precursor composition 32. Therefore, the molded body 34 can be prevented from sticking to the mold 30 by photopolymerization. At this time, the light (hν ₂ ) may be applied to the rib molded body 34 filled in the peripheral portion of the back plate 12. This is because this portion has already been cured by the irradiation of (hν ₁ ). After that, when the molding die 30 is removed from the back plate 12, when the molded body 34 is removed, as shown in FIG. The ribs 16 are integrally removed from the rear plate 12, and the ribs 16 are formed integrally with the rear plate 12 only at the center thereof.

It is desirable that the molded body 34 is not fixed to the peripheral portion of the back plate 12. A sealing agent is usually applied to the peripheral portion of the back plate 12 so that the front plate 14 and the back plate 12 are coated.
(Not shown). Alternatively, although not shown, an electrode terminal may be provided on a peripheral portion of the back plate 12 for electrical connection to the outside. Therefore, the rib precursor composition 32 is applied to the back plate 1 by the above method.
In the case where the molded body 34 is formed so as to protrude to the peripheral edge portion 2, the molded body 34 needs to be removed. Usually, a scraper is used to scrape off the molded body 34 at the peripheral edge of the back plate 12. However, in this case, the electrode terminals there may be damaged. Further, the rib precursor composition 32 filled in the peripheral portion of the molding die 30
Can be removed without curing. However, the uncured rib precursor composition 32 may flow when the mold 30 is removed, and may come into contact with the molded body 34.

However, in this embodiment, the molding die 30 cannot be used repeatedly. However, as described above, the removal of the molding 34 formed on the peripheral edge of the back plate 12 may damage the electrode terminals or cause the electrode terminals to be damaged. The cured rib precursor composition was formed into a molded product 3
4 can be carried out efficiently without contacting them.

[0044]

Example 1 In this example, a photosensitive paste was prepared as follows. First, a first photocurable component was prepared by mixing 10 g of bisphenol A diglycidyl ether methacrylic acid adduct (manufactured by Kyoeisha Chemical Co., Ltd.) and 10 g of triethylene glycol dimethacrylate (manufactured by Wako Pure Chemical Industries, Ltd.). . Next, this first photocurable component was used as a bis (2, 4, 6, 6) commercially available from Ciba-Geigy under the trade name Irgacure 819.
-Trimethylbenzoyl) -phenylphosphine oxide, 0.2 g of first photocuring initiator, 20 g of 1,3 butanediol as diluent, and 0.1 g of surfactant as surfactant.
2 g of phosphate propoxyl alkyl polyol (POC
A), 0.1 g of Dappo SN357 (San Nopco) was added as an antifoaming agent. The solution of lead glass which is commercially available from Asahi Glass (PbO-B2O3-SiO ₂₎ and a mixed powder (RFW-030) 80g of the inorganic oxide is dispersed. After dispersion, put the paste in a glass container and depressurize with a vacuum pump.
Bubbles in the paste were removed. In this case, paste 6
When heated to about 0 ° C., bubbles could be efficiently removed. Next, a mold having a concave portion corresponding to the shape of the rib was prepared. The mold was formed from the second photocurable component in the presence of 1% by weight of the second photocurable initiator. As the second photocurable component, Photomer 6010 from Henkel
An aliphatic urethane acrylate oligomer which is commercially available under the trade name is used. As the second photo-curing initiator, 2-hydroxy-2-methyl-1 commercially available from Ciba-Geigy under the trade name Darocure 1173
-Phenyl-propan-1-one was used. This is 38
It has an absorption edge corresponding to a wavelength of 0 nm. The photopolymerization of the second photocurable component was carried out by irradiation with light having a wavelength of 300 to 400 nm using a fluorescent lamp manufactured by Mitsubishi Electric OSRAM. Next, this photosensitive paste was filled between the concave portion and the back plate of the mold prepared as described above. Then
400-500 nm using a Philips fluorescent lamp
Of the first photocurable component was irradiated for 3 minutes. This light irradiation was performed simultaneously from both sides of the transparent mold and the transparent substrate (back plate). Thereafter, the molded body was removed from the mold integrally with the back plate. At this time, the molded article was easily removed from the mold without damaging the molded article or the back plate. In addition, no damage to the mold or the residual of the molded body in the mold was observed, and it was found that the mold could be used repeatedly.

Example 2 In this example, a photosensitive paste was prepared as follows. First, a first photocurable component was prepared by mixing 10 g of bisphenol A diglycidyl ether methacrylic acid adduct (manufactured by Kyoeisha Chemical Co., Ltd.) and 10 g of triethylene glycol dimethacrylate (manufactured by Wako Pure Chemical Industries, Ltd.). . Next, this first photocurable component was used as a bis (2, 4, 6, 6) commercially available from Ciba-Geigy under the trade name Irgacure 819.
-Trimethylbenzoyl) -phenylphosphine oxide, 0.2 g of first photocuring initiator, 20 g of 1,3 butanediol as diluent, and 0.1 g of surfactant as surfactant.
2 g of phosphate propoxyl alkyl polyol (POC
A), 0.1 g of Dappo SN357 (San Nopco) was added as an antifoaming agent. The mixed powder of lead glass which is commercially available in the solution from Asahi Glass (PbO-B2O3-SiO ₂₎ and an inorganic oxide (RFW-030) was dispersed powder mixture of 80g (RFW-030). After the dispersion, the paste was placed in a glass container, and the pressure in the paste was reduced to remove bubbles in the paste.
In this case, when the paste was heated to about 60 ° C., bubbles could be efficiently removed. Next, this photosensitive paste was filled between the concave portion of the mold prepared in Example 1 and the back plate. Next, after covering the central part of the mold with a light-shielding mask, light having a wavelength of 300 to 400 nm is applied to the peripheral part of the mold through a mold using a fluorescent lamp manufactured by Mitsubishi Electric OSRAM. The filled photosensitive paste was irradiated for 2 minutes. Next, the light-shielding mask was removed, and then, using a fluorescent lamp manufactured by Philips, 400 to 50
Light having a wavelength of 0 nm was irradiated for 1 minute to perform photopolymerization of the first photocurable component. This light irradiation was performed simultaneously from both sides of the transparent mold and the transparent substrate (back plate). Thereafter, the molded body was removed from the mold integrally with the back plate.
At this time, the compact was transferred to the center of the back plate. On the other hand, the molded body was not transferred to the peripheral edge of the back plate, and was fixed to the peripheral edge of the molding die. That is, the molded body at the peripheral edge of the back plate could be removed from the back plate integrally with the molding die.

Example 3 A photosensitive paste was prepared as follows. First, 24 g of γ-methacryloxypropylmethyldimethoxysilane (manufactured by Nippon Unicar) was prepared as a first photocurable component.
Further, after mixing 6 g of a mixed solution of 0.01 N nitric acid aqueous solution and ethanol having a molar ratio of 2: 1 and sufficiently stirring,
The reaction was maintained at 70 ° C. for 12 hours. Thereafter, the reaction product was dried at 70 ° C., and water and alcohol were removed by evaporation. Next, 8 g of methacrylic acid 2 was added to this liquid.
Hydroxyethyl (Wako Pure Chemical Industries, Ltd.) was added to obtain a first curable component. Further, 8 g of 1,3-butanediol (Wako Pure Chemical Industries, Ltd.) was used as a diluent, and 0.3 g of Irgacure 819 manufactured by Ciba Geigy was used as a first photocuring initiator.
And 0.2 g of POCA (phosphate propoxyl alkyl polyol) as a surfactant and 0.1 g of Dappo SN357 (San Nopco) as an antifoaming agent. Further, 70 g of α-alumina (AL-45-2, manufactured by Showa Denko KK) having an average particle size of 2.1 μm was dispersed in this solution to obtain a photosensitive paste. Further, bubbles were removed in the same manner as in Example 1. Next, this photosensitive paste was filled between the concave portion of the mold prepared in Example 1 and the back plate. Then, after covering the center of the mold with a light-shielding mask, using a fluorescent lamp manufactured by Mitsubishi Electric OSRAM, 300
Light having a wavelength of .about.400 nm was irradiated to the photosensitive paste filled in the peripheral portion of the mold through the mold for 2 minutes. Next, the light-shielding mask was removed, and then light having a wavelength of 400 to 500 nm was irradiated for 1 minute using a fluorescent lamp manufactured by Philips to photopolymerize the first photocurable component. This light irradiation was performed simultaneously from both sides of the transparent mold and the transparent substrate (back plate). Thereafter, the molded body was removed from the mold integrally with the back plate. At this time, the compact was transferred to the center of the back plate. On the other hand, the molded body was not transferred to the peripheral edge of the back plate, and was fixed to the peripheral edge of the molding die. That is, the molded body at the peripheral edge of the back plate could be removed from the back plate integrally with the molding die.

Comparative Example 1 In this example, the same photosensitive paste and mold as in Example 1 were used. However, the photopolymerization of the first photocurable component is
Instead of the fluorescent lamp manufactured by Philips, the above-described fluorescent lamp manufactured by Mitsubishi Electric OSRAM was used to irradiate the mold with light having a wavelength of 300 to 400 nm through the back plate. As a result, the adhesion between the mold and the molded body was strong, and the molded body could not be removed from the mold integrally with the back plate.
When the molded body was forcibly removed from the mold, the molded body was damaged.

COMPARATIVE EXAMPLE 2 In this example, light having a wavelength of 300 to 400 nm was applied to the periphery of the mold using a fluorescent lamp manufactured by Mitsubishi Electric OSRAM, not through the mold, but only on the back plate. After a molded body was produced in the same manner as in Example 2 except that irradiation was performed through the mold, the molding die was removed. At this time, at the center of the back plate, the molded body was separated from the mold and transferred to the substrate (back plate).
On the other hand, at the peripheral portion of the back plate, the molded body was fixed to both the mold and the substrate, and did not peel off well, or even if it peeled, it was damaged. That is,
It was not possible to remove the molded body at the peripheral edge of the back plate integrally with the molding die.

[0049]

According to the method for manufacturing a PDP substrate of the present invention, damage to the base and the ribs can be avoided, and the mold can be used repeatedly. In the method of manufacturing a PDP substrate according to the present invention, the rib precursor composition is irradiated with light having a wavelength shorter than the wavelength corresponding to the second absorption edge to form a rib molded body or a rib precursor composition at the peripheral portion of the base. This eliminates the need for an object removal step.

[Brief description of the drawings]

FIG. 1 is a partially exploded perspective view showing one embodiment of a PDP substrate.

FIG. 2 is a process chart showing a first embodiment of a method for manufacturing a PDP substrate of the present invention.

FIG. 3 is a process chart showing a second embodiment of the method for manufacturing a PDP substrate of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... PDP board 12 ... Back plate 14 ... Front plate 16 ... Rib 18 ... Discharge display cell 20 ... Address electrode 22 ... Bus electrode 24 ... Fluorescent layer 26 ... Dielectric layer 28 ... Concave part 30 ... Forming mold 32 ... Photosensitive paste (Rib precursor composition) 34: Rib molded body 36: Rib required area 38: Rib unnecessary area 40: Light shielding mask

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Akira Yoda 3-8-8 Minamihashimoto, Sagamihara-shi, Kanagawa F-term in Sumitomo 3M Limited (Reference) 5C027 AA09 5C040 FA01 FA04 GB03 GB14 GF02 GF19 JA19 KA08 KA16 MA23

Claims (10)

[Claims] A step of bringing a rib precursor composition including a first photocuring initiator having a first absorption edge and a first photocurable component into close contact with a substrate; In a mold obtained by photocuring the second photocurable component in the presence of a second photocuring initiator having a second absorption edge having a shorter wavelength than the wavelength corresponding to the first absorption edge. Filling the rib precursor composition, irradiating the rib precursor composition with light having a wavelength longer than the wavelength corresponding to the second absorption edge, and curing the rib precursor composition To form a rib on the substrate,
And a step of removing the mold from the substrate on which the obtained ribs are formed, a method for manufacturing a substrate for a plasma display panel. 2. A method of irradiating a light having a wavelength shorter than a wavelength corresponding to the second absorption edge to the rib precursor composition filled in the mold at a peripheral portion of a base, thereby forming the rib precursor composition The method according to claim 1, further comprising a step of curing the object. 3. The method according to claim 1, wherein the base and the mold are transparent, and irradiation of the rib precursor composition with light is performed through the base and the mold.
Production method described in 1. 4. The method according to claim 1, wherein the mold has flexibility. 5. The method according to claim 1, wherein the first photocuring initiator has the first absorption edge corresponding to a wavelength of 400 to 500 nm, and the second photocuring initiator corresponds to a wavelength of 300 to 400 nm. Claim 1 characterized by having a second absorption edge.
5. The production method according to any one of 4. 6. The method according to claim 1, wherein the first photocurable component and the second photocurable component are made of an acrylic resin. 7. The method according to claim 1, wherein the rib precursor composition contains a ceramic powder, and if necessary, a glass powder. . 8. A substrate formed from a rib precursor composition including a first photocurable initiator having a first absorption end and a first photocurable component, the rib being provided on the substrate. A mold for a plasma display panel substrate, comprising: a mold having a second absorption edge having a shorter wavelength than a wavelength corresponding to the first absorption edge of the first photocuring initiator. A mold obtained by photocuring the second photocurable component in the presence of the second photocuring initiator. 9. The mold according to claim 8, which has flexibility. 10. The method according to claim 8, wherein the transparent material is transparent.
Or the mold according to 9.