JP4500588B2 - Fine powder spraying device - Google Patents

Description

  The present invention relates to a technical field of a fine powder spraying device that discharges a fine powder together with a gas stream from a spray nozzle and sprays the fine powder onto a sprayed object such as a substrate.

  As a fine powder spraying device as described above, a uniform particle size between liquid crystal substrates constituting a liquid crystal display plate used in a liquid crystal display device or the like, for example, between a glass plate and a glass plate or a plastic substrate. As a typical example, there is known a liquid crystal spacer spraying device that sprays a predetermined amount of liquid crystal spacers (spacer beads), which is a fine powder of the above, uniformly in a single layer.

In a liquid crystal display panel such as a liquid crystal display device, between a glass plate and a glass plate constituting a liquid crystal substrate, or between a plastic substrate (such as organic glass) other than the glass plate, or between this plastic substrate and glass In order to form a gap for injecting liquid crystal between the plates (hereinafter, represented by a glass substrate composed of a glass plate and a glass plate and referred to as a glass substrate), the particle diameter is several μm to several tens of μm. Using particles of uniform diameter (spacer beads) as spacers, about 10 to 2000 particles per 1 mm ² are dispersed as uniformly as possible into a single layer. As the liquid crystal spacer, various plastic particles and silica particles are used.

As a device for spraying liquid crystal spacers uniformly and in a predetermined amount in a single layer on a glass substrate as a liquid crystal substrate, the above-described liquid crystal spacer spray device is known. As a liquid crystal spacer spraying device, a device using a gaseous gas such as air or nitrogen gas as disclosed in Patent Document 1, for example, is known.
This spacer spraying device for liquid crystal is used for placing liquid crystal spacers on a gas stream such as air or nitrogen gas, transporting the inside of a thin pipe (transport pipe), and for the liquid crystal together with the air stream from the swinging spray nozzle pipe The spacer particles are discharged on the glass substrate.

  However, as described above, the liquid crystal spacer is easily floated with a fine powder having a particle diameter of several μm to several tens of μm, and the liquid crystal spacer particles are made of various plastic particles or silica particles. Therefore, it is easy to be charged, and it is difficult to spread it on a glass substrate with a constant density with good reproducibility. Therefore, normally, the liquid crystal spacer particles are charged in accordance with their charging polarity (electrostatic polarity), and the glass substrate is grounded (grounded) with a rotating table on which the glass substrate is placed. The liquid crystal spacer particles can be reliably dispersed at a constant density.

  By the way, in recent years, as the liquid crystal display panel is gradually increased in size, a large number of liquid crystal display panels are often manufactured from a single glass substrate, and it is required to disperse liquid crystal spacers in a wider range. It has become to. In order to cope with this, the mounting base (base) of the glass substrate is enlarged, the height of the spraying chamber (chamber) is increased, or the swing angle required for the spraying nozzle tube for spraying the liquid crystal spacer is set. Need to increase.

  Here, if the glass substrate mounting base (base) is made large and the spraying chamber (chamber) height is made high, the spraying device itself becomes large, but the ceiling height of the clean room where the liquid crystal spacers are sprayed is Due to the limitations, the ceiling height of the clean room has to be specially designed and increased, resulting in a problem of increased costs. In particular, when the size of the glass substrate increases and becomes about 1300 mm × 1300 mm, there is a problem that the conventional spraying system cannot enter the current clean room.

  Further, regarding the point of increasing the swing angle required for the spray nozzle tube for spraying the liquid crystal spacer, the conventional swing method of the spray nozzle tube is realized by a crank or an eccentric cam. The nozzle tube does not move at a constant speed, and there is a problem that the moving speed fluctuates significantly at both ends.

  The above-mentioned liquid crystal spacer spraying device disclosed in Patent Document 1 is a device developed to cope with this requirement. That is, in the liquid crystal spacer spraying device disclosed in Patent Document 1, the spray nozzle tube disposed at a predetermined interval from the sprayed object can be tilted in any of two plane directions orthogonal to each other. The swing angle of the spray nozzle tube is conventionally increased without increasing the distance between the spray nozzle tube and the object to be sprayed by synthesizing the swing by the two swing mechanisms described above. The operation is made smoother and the operation is smoother.

Japanese Patent Laid-Open No. 11-276941

  According to the liquid crystal spacer spraying device disclosed in Patent Document 1, the swing angle of the spray nozzle tube is increased from that of the conventional one without increasing the distance between the spray nozzle tube and the object to be sprayed. Although the effect of smoothing the operation can be obtained, another problem has been pointed out also in this apparatus.

  This problem is common to conventional liquid crystal spacer spraying devices including the liquid crystal spacer spraying device disclosed in Patent Document 1, and a part of the particles ejected from the spray nozzle tube is sprayed. Adhering to the vicinity of the particle outlet of the nozzle tube, in particular to a dust-proof cover made of rubber or the like that protects this particle outlet, and if this deposit accumulates to some extent, the aggregates are caused by some reason (for example, vibration of the device). Etc.), and the dispersion uniformity of the liquid crystal spacer particles on the sprayed body is impaired.

  The present invention has been made in view of the above circumstances, and the object of the present invention is to solve the problems in the prior art, without causing the aggregates to fall on the objects to be sprayed. An object of the present invention is to provide a fine powder spraying device capable of spraying a fine powder such as a liquid crystal spacer on a spray body.

In order to achieve the above-mentioned object, the present invention is arranged at a predetermined distance from a chamber and an object to be dispersed in the chamber, and the tip of the fine powder together with an air flow of the gas body with respect to the object to be dispersed. A spraying device for discharging fine powder, a dustproof cover covering the periphery of the spraying nozzle, and a support part for supporting the object to be sprayed in the chamber , further comprising a periphery of the spraying nozzle In order to prevent the fine powder from adhering to the dust-proof cover , the anti-adhesion flow-forming gas supply unit for spraying the anti-adhesion flow-forming gas toward the outer peripheral surface of the dust-proof cover is provided. A fine powder spraying device is provided .

Furthermore, the supply portion of the anti-adhesion flow forming gas, said Ri Na is disposed so as to surround the dust cover, by spraying the adhesion prevention flow forming gas toward the outer peripheral surface of the dust-proof cover, the dustproof It characterized that you form a curtain of the antiadhesive flow forming gas on the outer peripheral surface of the cover. The dustproof cover may be made of a flexible material.

Here, the spray nozzle further includes a swing mechanism that swings the spray nozzle in two orthogonal directions, and the spray nozzle is swung in two orthogonal directions by the swing mechanism, The spray position of the fine powder with respect to the spray body may be changed. Here, the term “movable” includes not only mechanical movement of the nozzle but also aerodynamic movement in which the gas supply direction is changed to change the spraying direction of the fine powder. In the latter case, the dust-proof cover is preferably provided around the spray nozzle or around a hood or the like that supports the spraying direction of the fine powder sprayed from the spray nozzle.

The adhesion preventing flow forming gas supply unit has an adhesion preventing flow forming gas holding portion having an opening substantially corresponding to the movement region of the dust cover and the spray nozzle. It is preferable that the adhesion preventing flow forming gas supplied to the flow forming gas holding portion is ejected from the opening to discharge the dust-proof cover and the fine powder flying around it.
Further, the adhesion preventing flow forming gas holding portion has a box shape and is provided between the ceiling portion of the chamber and the swinging mechanism, and is provided on a side surface of the box shape preventing gas forming portion for forming the adhesion preventing flow. It is preferable to have a gas blowing pipe for forming the adhesion preventing flow.
Further, the opening is provided on each surface of the box-shaped gas holding portion for preventing adhesion flow forming on the ceiling side of the chamber and the swinging mechanism side, An opening substantially corresponding to the opening of the gas holding portion for forming an anti-adhesion flow, and the opening of the gas holding portion for forming an anti-adhesion flow and the opening of the ceiling of the chamber are Larger from the moving mechanism side toward the ceiling portion of the chamber, and is large enough not to interfere with movement of the spray nozzle by the swing mechanism by inserting the spray nozzle and the dustproof cover protruding from the swing mechanism. It is preferable.

As the adhesion preventing flow forming gas, various clean gases including air can be suitably used. Moreover, it is preferable that the flow velocity of the clean air for forming the anti-adhesion flow is 1/10 or less of the flow velocity of the fine powder-containing gas ejection flow from the spray nozzle.
Furthermore, it is preferable to have a blower that collects the fine powder sprayed into the chamber from the spray nozzle and sprayed outside the body to be sprayed by sucking and removing from the chamber through an exhaust pipe.

  According to the present invention, a fine powder spraying device capable of spraying fine powders such as liquid crystal spacers on a large-scale sprayed body without causing agglomerates to fall on the sprayed body is realized. can do.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a cross-sectional view showing a schematic configuration of an example of a fine powder spraying apparatus 10 to which the present invention is preferably applied. The fine powder spraying apparatus 10 according to the present embodiment is usually installed in a clean room (not shown). That is, in the fine powder spraying device 10 according to the present embodiment, the object to be sprayed is placed on the base 14 provided with the rotary table on which the glass substrate is placed on the top, which is disposed in the lower part of the sealed chamber 12. A glass substrate 16 is placed and positioned and fixed. Here, the base 14 may not include the rotary table as described above.

  The base 14 and the glass substrate 16 placed on the base 14 are grounded (grounded) or charged with a voltage having a polarity opposite to that of the charged fine powder, and the liquid crystal spacer particles (hereinafter referred to as “charged fine powder”). This is referred to as a spacer 20 and is reliably attached to the glass substrate 16 grounded through the ground wire 34.

  As for the spray nozzle 18 of the spacer spray mechanism 22 used here, for example, the applicant previously applied Japanese Patent Application No. Hei 4-166258 “Powder Sprayer and Spray Method” (see Japanese Patent Laid-Open No. 6-3679). Although the proposed cam-type spray nozzle swinging mechanism for swinging the spray nozzle in two orthogonal directions (x and y directions) on the glass substrate is provided, the present invention is not limited to this.

  More specifically, the fine-powder spraying apparatus 10 shown in FIG. 1 uses an air flow including a spacer supplied from a spacer supply mechanism 26 having a gas supply source 28 for supplying clean air or the like to a transport pipe. 24 is guided to the spacer spraying mechanism 22, and the spacer 20 is sprayed on the surface of the glass substrate 16 on the base 14 from the spray nozzle 18 controlled to swing in the x and y directions on the glass substrate 16 as described above. To do. Of the dispersed spacer 20, the portion that has not been dispersed on the glass substrate 16, that is, the spacer that has been dispersed outside the glass substrate 16, is suctioned (recovered) by the blower 30 through the exhaust pipe 32. . As described above, a different spacer spraying mechanism may be used.

In FIG. 2, the dispersion | distribution condition of the spacer 20 to the glass substrate 16 surface by the above-mentioned spacer dispersion | distribution mechanism 22 is shown typically. FIG. 2 shows that the spray nozzle 18 of the spray mechanism 22 swings in the x and y directions as described above by the cam mechanism, and thereby the substantially rectangular spray including the surface of the glass substrate 16. This is a situation where spacers are sprayed on the area. Here, the hatched area in FIG. 2 indicates the area outside the glass substrate 16, and the spacers 20 dispersed therein are the targets for suction removal (collection).

  By the way, the feature of the fine powder spraying device according to the present invention corresponds to the sprayed spacer agglomeration prevention mechanism in the vicinity of the spacer spraying mechanism 22 (the “adhesion prevention flow forming gas supply unit” in the claims). , Hereinafter referred to as an anti-agglomeration mechanism). The detailed configuration and function of the aggregation preventing mechanism 40 will be described below with reference to FIGS.

  Here, FIG. 3 is an exploded perspective view showing a situation in which the agglomeration prevention mechanism 40 is disposed between the spacer scattering mechanism 22 and the ceiling 12a of the chamber 12 (above the ceiling 12a of the chamber 12). FIG. 4 is an assembled cross-sectional view illustrating a state in which these are actually assembled, and also explaining the operation thereof.

  As shown in both figures, the spray nozzle 18 is held in a projecting manner on the lower surface of the spacer spray mechanism 22, and a nozzle swing mechanism 22 a (FIG. 4) provided inside the spacer spray mechanism 22. The spacers 20 are dispersed on the surface of the glass substrate 16 while the position is controlled by the reference). In the figure, reference numeral 50 denotes a dust-proof cover for preventing wear debris that may be generated from a mechanism portion such as the above-described nozzle swinging mechanism from falling on the surface of the glass substrate 16, for example, silicon rubber. It is comprised with flexible materials, such as.

  As described above, in the conventional fine powder spraying device, a part of the spacer which is sprayed into the chamber 12 and scattered around the dustproof cover 50 (outer peripheral surface) adheres, The problem is that the glass substrate 16 may fall on the surface of the glass substrate 16 as a trigger, and the present invention is to solve this problem.

  As shown in both figures, the lower surface of the spacer spraying mechanism 22, the anti-aggregation mechanism 40 (upper and lower surfaces), and the ceiling 12 a of the chamber 12 do not hinder the movement of the spray nozzle 18 of the spray mechanism 22. Are provided with rectangular cutouts 22b, 40a, 40a and 12b. It should be noted that the cutout portions 22b, 40a and 12b are preferably configured to be larger in the lower direction according to the swing angle of the spray nozzle 18.

  As is clear from the drawing, the aggregation preventing mechanism 40 is formed in a thin box shape here, and is configured to allow the spray nozzle 18 and the dust cover 50 protruding from the spacer spray mechanism 22 to pass therethrough. An air blowing tube 40b is disposed near the center of each side of the rectangular shape. The four air blowing pipes 40b are supplied with compressed air whose pressure is adjusted from an air source (not shown) through an air supply tube 40c.

  The shape of the anti-agglomeration mechanism 40 is not limited to the rectangular box shape as described above, and is an arbitrary planar shape, and has a configuration having only one of the upper and lower surfaces without being a box shape, It is also possible to have a configuration having only the wall surface. When the bottom surface or the ceiling surface is omitted in this way, it is preferable to arrange an appropriate packing on the surface that contacts the spacer spraying mechanism 22 or the ceiling portion 12a of the chamber 12, respectively.

  Further, the number of air blowing pipes 40b, the mounting positions, and the like are not limited to the above configuration. Further, as will be described later, the amount of air supplied to each of the air blowing pipes 40b described above is the size of the notch 12b of the chamber 12 corresponding to the final air outlet (actually dust-proof from there) In consideration of the area obtained by subtracting the area of the air flow inhibiting portion such as the cover 50, etc., it is determined so that an optimal air outflow speed can be obtained from the notch 12b.

  The fine powder spraying device 10 according to the present embodiment configured as described above generally operates as follows.

  That is, in the anti-aggregation mechanism 40, when the pressure-adjusted air blown from each of the air blow pipes 40b described above is once blown to the outer peripheral surface of the dustproof cover 50, there is a spacer attached thereto. In addition to the action of peeling it, the peeled spacer is discharged to the outside of the aggregation preventing mechanism 40 through the lower notches 40a and 12b. Thereby, the problem that a spacer accumulates on the outer peripheral surface of the dustproof cover 50, and aggregates and falls can be solved.

  More specifically, as shown in FIG. 4, the air blown into the aggregation preventing mechanism 40 from each air blowing tube 40 b of the aggregation preventing mechanism 40 during the dispersion of the spacer 20 is indicated by an arrow A. Then, a kind of air curtain is formed on the outer peripheral surface of the dust-proof cover 50, and the spacer 20 sprinkled up from the spray nozzle 18 is prevented from reaching the outer peripheral surface of the dust-proof cover 50.

Further, since this air advances as shown by arrow A and is blown to the outer peripheral surface of the dust cover 50, if there is a spacer adhering thereto as described above, it is peeled off, and arrow B As shown, it is discharged out of the aggregation prevention mechanism 40.
By these actions, the amount of adhesion of the spacer 20 to the outer peripheral surface of the dust-proof cover 50 that causes the aggregate to fall can be greatly reduced, and the effect of reducing the fall of the aggregate can also be obtained.

  In the description of the above embodiment, the present invention has been described by taking the case where the spray nozzle 18 is positioned directly above the glass substrate 16 as an example, but the present invention is not limited thereto, and the spray nozzle 18 It may be in a position off the glass substrate 16 (base 14), and when it is along the x or y direction with respect to the glass substrate 16 or is inclined from these directions. Or any of them.

  Hereinafter, the result of an experiment for confirming the effect of the aggregation preventing mechanism 40 using the fine powder spraying device provided with the aggregation preventing mechanism 40 shown in the above embodiment will be described.

Experimental conditions:
Three glass substrates (substrate a, substrate b, substrate c: 400 mm × 500 mm each) were arranged on a substrate mounting table (1360 mm × 1760 mm) on a base in a clean room as shown in FIG.
The spray nozzle (nozzle unit) was arranged in the center upper part of the base (hereinafter referred to as the upper part of the substrate).

Other experimental conditions:
The N ₂ gas flow rate from the spray nozzle was 60 l / min (average flow velocity: 80 m / sec).
Spacer used: SP-203 (manufactured by Sekisui Chemical Co., Ltd.) was used.
The nozzle swing angle was 15.5 ° per side (31 ° overall).
Nozzle rocking speed: Reciprocating motion was 90 times / min.

Air outflow speed (average flow speed) from the aggregation preventing mechanism 40: 0.5 m / sec.
After performing preliminary (dummy) spacer spraying (1500 shots (spraying amount: about 30 g)), nozzle swinging (operation) for 100 shots was performed.
The number of rotations of the substrate mounting table was 30 rpm.
The air outflow rate from the aggregation preventing mechanism 40 is preferably about 1/10 or less of the N ₂ gas flow rate from the spray nozzle 18.

Result measurement method: Light for surface observation (made by NICHIDEN) from the lateral direction of the substrate to be measured
A light pitcher outdoor type (300 W) was applied, and bright spots (dust) were observed and counted with a microscope (manufactured by MITUTOYO).
The experiment was repeated twice with different days. The results are shown in Table 1.

  In Table 1, “air purge: yes” means that “air jetting” was performed by the aggregation preventing mechanism 40, and “air purge: no” means that “air jetting” was not done. Means. The average aggregate number, which is an evaluation value, is an average value of the measured values of the three glass substrates described above.

  As is clear from Table 1, the difference in presence or absence of the aggregation preventing mechanism 40 is obvious. From this result, it was proved that the spacers can be smoothly dispersed without generating the aggregates of the spacers by disposing the aggregation preventing mechanism 40 in the fine powder spraying device.

  In addition, when the spray nozzle (nozzle unit) is arranged at a position off the table, it is predicted that the agglomerate will fall on the glass substrate less than when the spray nozzle (nozzle unit) is arranged on the top of the substrate. Is done.

  The above embodiment shows an example of the present invention, and the present invention should not be limited to this, and appropriate modifications or improvements can be made without departing from the scope of the present invention. Needless to say, it is good.

  For example, as the spray nozzle unit that can be used in the fine powder spray device according to the present invention, the one shown in the embodiment (ie, Japanese Patent Application No. 4-166258 “Powder spray device and spray method” (Japanese Patent Laid-Open No. In addition to the one proposed by the Japanese Patent No. 3679), those disclosed in the Japanese Patent Laid-Open No. 11-276941, and those disclosed in the Japanese Patent Laid-Open No. 2002-148635 can be cited. .

It is sectional drawing which shows schematic structure of an example of the spraying apparatus of the fine powder to which this invention is applied suitably. It is a figure which shows typically the dispersion | distribution condition of the spacer to the glass substrate surface by the spacer dispersion | distribution mechanism shown in FIG. It is a disassembled perspective view explaining the structure of the aggregation prevention mechanism of the spacer which concerns on an Example. FIG. 4 is an assembled cross-sectional view for explaining the state in which each part shown in FIG. 3 is actually assembled and its operation. It is a figure which shows the arrangement | positioning condition of the glass substrate used for experiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Fine powder spraying device 12 Chamber 12a Chamber ceiling part 12b, 22b, 40a Notch part 14 Base 16 Glass substrate 18 Spray nozzle 20 Spacer 22 Spacer spray mechanism 22a Nozzle swing mechanism 24 (Spacer) Transport pipe 26 Spacer supply Mechanism 28 Gas supply source 30 Blower 32 Exhaust pipe 34 Ground wire 40 Aggregation prevention mechanism 40b Air blowing pipe 40c Air supply tube 50 Dust cover

Claims (10)

A chamber;
A spray nozzle that is disposed at a predetermined distance from the object to be sprayed disposed in the chamber, and discharges fine powder from the tip of the sprayed object together with a gas stream;
A dustproof cover covering the periphery of the spray nozzle;
In the chamber, a support unit for supporting the object to be sprayed, and a fine powder spraying device,
Further, supply of the anti-adhesion flow forming gas for blowing the anti-adhesion flow forming gas toward the outer peripheral surface of the dust-proof cover in order to prevent the fine powder from adhering to the dust-proof cover around the spray nozzle. A fine powder spraying device characterized by comprising a portion. Supply of the adhesion prevention flow-forming gas, wherein Ri Na is disposed so as to surround the dust cover, by spraying the adhesion prevention flow forming gas toward the outer peripheral surface of the dust-proof cover, the outer periphery of the dust-proof cover spraying devices fine powder according to claim 1, characterized that you form a curtain of the antiadhesive flow forming gas on the surface. 3. The fine powder spraying device according to claim 1, wherein the dustproof cover is made of a flexible material. Furthermore, it has a swing mechanism that swings the spray nozzle in two orthogonal directions,
It said distributing nozzle, the is swung in the two orthogonal directions by swinging mechanism, wherein said any one of claims 1-3, characterized in that to change the spray position of the fine powder with respect to the diaspore Fine powder spraying device. The adhesion preventing flow forming gas supply unit has an adhesion preventing flow forming gas holding unit provided with an opening substantially corresponding to the movement region of the dust cover and the spray nozzle,
The anti-adhesion flow forming gas supplied to the anti-adhesion flow forming gas holding portion has a function of discharging the dust-proof cover and the fine powder flying around the dust-proof cover by ejecting the gas from the opening. The fine powder spraying device according to claim 4 , wherein the fine powder spraying device is provided. The adhesion preventing flow forming gas holding portion has a box shape, and is provided between the ceiling portion of the chamber and the swing mechanism,
6. The fine powder spraying device according to claim 5, further comprising a blow-in pipe for forming the anti-adhesion flow forming gas on a side surface of the box-shaped gas holding portion for forming the anti-adhesion flow. The opening is provided on each surface of the box-shaped gas holding part for forming an anti-adhesion flow on the ceiling side and the swinging mechanism side of the chamber,
The ceiling of the chamber has an opening substantially corresponding to the opening of the gas holding part for preventing adhesion flow formation,
The opening of the gas holding portion for preventing adhesion flow formation and the opening of the ceiling of the chamber are larger from the swing mechanism side toward the ceiling portion of the chamber, and protrude from the swing mechanism. The fine powder spraying device according to claim 6, wherein the spraying nozzle and the dustproof cover are inserted so as not to interfere with movement of the spray nozzle by the swing mechanism. The fine powder spraying device according to any one of claims 1 to 7 , wherein the adhesion preventing flow forming gas is a variety of clean gases including air. Blowing velocity of the anti-adhesion flow forming gas is in any one of claims 1 to 8, wherein less than 1/10 of the flow rate of the fine powder-containing gas ejected flow from the spray nozzle The fine powder dispersion device described. The apparatus further comprises a blower that collects the fine powder sprayed into the chamber from the spray nozzle and sprayed out of the body to be sprayed through the exhaust pipe through the exhaust pipe. The fine powder spraying apparatus according to any one of 1 to 9.

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