JPH0843832A - PARTICLE SPRAYING METHOD AND PARTICLE SPRAYING APPARATUS - Google Patents

Abstract

(57) [Abstract] [Purpose] Even if a dusting material powder that is originally aggregated due to moisture absorption or static electricity is used, it is possible to spray fine particles uniformly without being spread as a nodule on the material to be spread. Provided are a fine particle spraying method and a fine particle spraying device. [Constitution] In the dry spray method, the fine particles 5 are filtered by
When it is passed through, the particles are first physically decomposed into individual fine particles 5. Moreover, during this decomposition, the fine particles 5 are charged depending on the material of the filter 4, and the fine particles 5 are further charged by the charger. At this time, charging is performed with the same polarity so that the fine particles 5 are not reaggregated by using the electric repulsion force. Alternatively, in order to avoid re-aggregation due to difference in positive or negative charge between the charged fine particles 5,
Electrically neutralize.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fine particle spraying method and a fine particle spraying apparatus.

[0002]

2. Description of the Related Art Conventionally, generally used spraying methods include a dry spraying method (electrostatic spraying method) in which static electricity of the same polarity is charged on fine particles and spraying, and a spraying method in which fine particles are mixed with a quick-drying solvent. There is a wet spraying method.

What is important in fine particle application is that the application density is uniform in the surface and that a large particle mass cannot be formed. Also, ease of spraying work is important.

Looking at the conventional fine particle spraying technology from these viewpoints, the wet spraying method requires the work of mixing and mixing the solvent and the fine particles. The good and bad influences the state of spraying.

However, this wet spraying method has a problem that the fine particles are re-agglomerated in the solvent during the mixing and mixing operations of the solvent and the fine particles to cause nodules.

On the other hand, in the dry spraying method (electrostatic spraying method), the fine particles are charged to the same polarity and dispersed by preventing the particles from aggregating due to the electrostatic repulsion force.

However, when the fine particles (so-called spraying material powder) before electrostatic spraying are aggregated by moisture absorption to form a nodule, the nodules are directly formed on the object to be scattered (for example, in the case of a liquid crystal display device). On the array substrate, etc.). Therefore, there is a case where an operation of drying the spray material powder in advance is added, which causes a problem that the process is complicated.

[0008]

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and its purpose is to obtain a powder of a spraying material which has already agglomerated before the spraying step is introduced due to moisture absorption or static electricity. It is an object of the present invention to provide a fine particle spraying method and a fine particle spraying device for performing the uniform spraying of fine particles even if they are used as a lump, without being sprayed on the object to be sprayed.

[0009]

The method for spraying fine particles of the present invention comprises the steps of ejecting fine particles together with gas from an outlet, and passing the fine particles through the holes of a filter having at least one hole, Of the fine particles, a step of separating the fine particles that have been aggregated into an agglomerate into individual fine particles,
Charging the fine particles to the same polarity and holding the fine particles in a separated state by the charged charges having the same polarity; and a step of spraying the charged fine particles on the object to be spread. Is a method for spraying fine particles.

Further, the step of ejecting the fine particle powder together with the gas from the air outlet and the fine particles are passed through the holes of the filter having at least one hole, and the fine particles are aggregated into a nodule. Separating the particles into individual particles and charging the particles to the same polarity; and further charging the particles to the same polarity and holding the particles in a separated state by the charged charges of the same polarity. A method for spraying fine particles, comprising: a step; and a step of spraying the charged fine particles on an object to be sprayed.

Further, a step of ejecting fine particles together with a gas from a blowout port, and passing the fine particles through the holes of a filter having at least one hole, to remove the fine particles that have been aggregated into agglomerates among the fine particles. Separating the individual fine particles and charging the fine particles to the same polarity, and holding the fine particles in a separated state by the charged electric charges of the same polarity; and the fine particles charged by the filter on the sprayed body. And a step of spraying on the fine particles.

[0012] Further, a step of ejecting fine particles together with a gas from the outlet, and passing the fine particles through the holes of a filter having at least one hole to remove the fine particles that have been aggregated in a nodule. Characterized in that it includes a step of separating the particles into individual particles, a step of removing the charge of the particles to maintain the particles in a separated state, and a step of spraying the charged particles on the object to be dispersed. This is a method for spraying fine particles.

Further, in the method for spraying fine particles according to any one of the above, as the filter, a filter having a hole having a size capable of passing one to three fine particles at a time is used. Is a method for spraying fine particles.

Further, in the method for spraying fine particles according to any one of the above, as the filter, a filter made of a material having a positive charging order with respect to the fine particles and making the charge polarity of the fine particles negative by passing through the filter. Is used, and the fine particles are further negatively charged by a charging device.

Further, in the method for spraying fine particles according to any one of the above, the filter is made of a material having a negative charging order with respect to the fine particles and making the charge polarity of the fine particles positive by passing through the filter. Is used and the fine particles are further positively charged by a charging device.

Further, in the fine particle spraying apparatus of the present invention, at least an outlet for ejecting the fine particles together with the gas, and at the time of passing the fine particles, the fine particles that have been aggregated in the agglomerate form are separated into individual fine particles. A fine particle spraying device comprising a filter having one hole, a charger for charging the fine particles to the same polarity, and a mounting table on which a sprayed body on which the fine particles are sprayed is placed. Is.

Further, a blowout port for ejecting the fine particles together with the gas and the fine particles, which are aggregated in the agglomerate of the fine particles when passing through the fine particles, are separated into individual fine particles and the fine particles are charged to the same polarity. at least
A fine particle spraying device comprising a filter having one hole, a charger for charging the fine particles to the same polarity, and a mounting table on which a sprayed body on which the fine particles are sprayed is placed. Is. Also, at least one of an outlet for ejecting fine particles together with gas and at least one for separating the fine particles that have been aggregated into aggregates among the fine particles when passing through the fine particles into individual fine particles and charging the fine particles to the same polarity A fine particle spraying device comprising: a filter having holes; and a mounting table on which a sprayed body on which fine particles charged by the filter are sprayed is mounted.

Further, there is provided a blowout port for ejecting fine particles together with the gas, and a filter having at least one hole for separating the fine particles, which are aggregated in the agglomerate of the fine particles when passing through the fine particles, into individual fine particles. And a static eliminator for neutralizing the charge of the fine particles, and a mounting table on which a material to be dispersed on which the fine particles are dispersed are mounted.

In the fine particle spraying device according to any one of the above, the fine particles 1 may be used as the filter.
A fine particle spraying device comprising a filter having a plurality of holes each having a size capable of passing one to three at a time.

In the fine particle spraying device according to any one of the above, as the filter, a filter made of a material having a negative charging order with respect to the fine particles and positively charging the fine particles by passing through the filter is used. Is a fine particle spraying device.

Further, in the fine particle spraying device according to any one of the above, as the filter, a filter made of a material having a positive charging order for the fine particles and making the charge polarity of the fine particles negative by passing through the filter. A fine particle spraying device characterized by being used.

The planar shape of the outer circumference of the holes of the filter may be circular or regular polygonal, for example. Alternatively, it may have a mesh shape.

[0023]

In the present invention, in the dry spraying method, when the fine particles are passed through the filter, they are first physically decomposed into individual fine particles. Moreover, during this decomposition, fine particles are charged depending on the material of the filter, and the fine particles are further charged by a charger. At this time, the electric charges are charged to the same polarity, and the electric repulsive force is used to prevent re-aggregation of the fine particles. Alternatively, the particles are electrically neutralized so as not to reaggregate due to a difference in positive or negative charge between charged fine particles. In this way, the respective fine particles are dispersed and sprayed onto the spray target. Therefore, it is possible to uniformly disperse the fine particles on the object to be dispersed without agglomerating them into aggregates.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a fine particle spraying method and a fine particle spraying apparatus according to the present invention will be described below in detail with reference to the drawings.

(Embodiment 1) Hereinafter, the method for spraying fine powder according to the present invention will be described with reference to the case where spacers are sprayed as fine particles on a liquid crystal cell substrate of a liquid crystal display device.

FIG. 1 is a sectional view showing the outline of the structure of a fine particle spraying device according to the present invention.

A substrate 2 which is an object to be scattered is placed under the spraying tank 1, and a spraying nozzle 3 is arranged almost directly above the substrate 2.

An ionizer is incorporated in the spray nozzle 3. Note that this ionizer is not necessarily required. In the present embodiment, a mesh-like filter 4 having a fine mesh is provided in a cylindrical shape so as to surround the spray nozzle 3, and a material for depositing the material powder of the fine particles 5 for spraying is placed directly below the spray nozzle 3 inside the filter 4. The powder plate 6 was placed. An ionizer 7 is arranged near the filter 4.

The fine particles 5 blown off by the spraying nozzle 3 pass through the filter 4 and are blown out into the spraying tank 1 and fall naturally onto the substrate 2 which is the sprayed object. At this time, the size of the fine particles 5 passing therethrough is limited in accordance with the mesh size of the filter 4 (that is, the size of the opening of the hole). do not do. Since these nodules are not strongly bonded, they are separated from each other when they collide with the mesh of the filter 4 and pass as individual particles.

In the present embodiment, as the fine particles 5, spherical spacers made of a resin material used as a spacer of a liquid crystal display device and having a particle diameter of 5 μm were used. The roughness of the mesh of the filter 4 is about 1.8 times the particle diameter of the fine particles 5, that is, 9
The thing with a micrometer was used.

The particle diameter of the fine particles according to the present invention is preferably 1 μm to 20 μm in the case of a spacer used in a liquid crystal display device like the fine particles 5 described above. However, more generally, the particle size of the fine particles according to the present invention can be 20 μm or more. As for the upper limit, in the case of a sphere, generally, as the particle size increases, the influence of the electrostatic attraction force between the spheres on the same amount of charge becomes extremely small compared to the volume thereof, so there is no theoretical limit. In consideration of these, the present invention can be applied to fine particles having a particle size of 20 μm to 1 mm.

FIG. 2 is a diagram showing the effect of the present invention. This is the correlation between the spray density and the frequency of occurrence of fine particle lumps. In the above embodiment, the roughness of the mesh of the filter 4 is set to the fine particles 5.
However, as a result of experiments by changing the roughness of the mesh, the occurrence rate of fine particle lumps is reduced by increasing the roughness of the mesh from 1 to 3 times the particle diameter. I found out what to do.
It goes without saying that as the coarseness of the mesh increases, the rate of occurrence of the nodule increases, but the roughness of the mesh (that is, the size of the pores of the filter 4) should be set according to the permissible value of the nodule. You can For example, in order to disperse the individual fine particles 5 without forming nodules at all, a filter in which pores having a mesh size, that is, a size having a margin of the size tolerance of the fine particles 5 is provided. 4 is used.

(Embodiment 2) The present inventors examined the charging polarity of the fine particles 5 after passing through the filter 4.

As the fine particles 5 to be sprayed, those whose main component is divinylbenzene were used. As the filter 4, a filter having a mesh made of stainless steel was used. Then, the generation rate of the nodule of the fine particles was examined when the negative ions were applied to the fine particles 5 after passing through the mesh of the filter 4 by the ionizer 7 as a charger and when the positive ions were applied.

As a result, when negative ions are applied, 3
The incidence of nodules formed by agglomeration of individual fine particles was 0.5%, and 0.9% when positive ions were applied.

We have found that this difference is due to the following reasons. That is, when the charge of the fine particles 5 passing through the mesh of the filter 4 was examined, it was found that they were negatively charged. This is due to the triboelectrification order of stainless steel, which is the material for forming the filter 4, and divinylbenzene, which is the material for forming the fine particles 5.

Therefore, when the negative ions are applied to the fine particles 5 after passing through the mesh of the filter 4, the electrostatic repulsion force (repulsion) between the fine particles 5 becomes stronger and the nodule generation rate becomes smaller. Understandable.

In the above embodiment, the filter 4
Stainless steel was used for the fine particles 5 and divinylbenzene was used for the fine particles 5. However, when silica is used for the fine particles 5, the fine particles 5 after passing through the filter 4 are positively charged according to the charging order. It is preferable to apply positive ions to the subsequent fine particles 5.

In addition, the material of the filter 4 and the fine particles 5
The polarity of the ionizer 7 after passing through the filter 4 may be changed according to the material of the. That is, when the fine particles 5 are positively charged after passing through the filter 4, in order to further charge the fine particles 5 and disperse them by the electrostatic repulsion force, the fine particles 5 are further positively charged after passing through the filter 4. Positive ions are applied from the ionizer 7 so as to be charged. When the fine particles 5 are negatively charged after passing through the filter 4, negative ions are applied from the ionizer 7.

(Embodiment 3) In the first embodiment, an example in which the fine particles 5 are charged to the same polarity by the ionizer 7 was introduced, but the same apparatus as described above is used to pass through the filter 4 to decompose the particles. A method of electrostatically neutralizing the fine particles 5 charged by friction or the like and spraying the fine particles 5 is also possible. In this case, contrary to the first embodiment described above, charging is performed with the same degree of charge as the polarity opposite to that of the particles 5 when they pass through the filter 4. That is, when the fine particles 5 are positively charged when they pass through the filter 4, negative ions are applied to the fine particles 5 from the ionizer 7 and the negative charges (negative charge) of the negative ions are applied to the fine particles 5.
Neutralize the positive charge of. By electrostatically neutralizing the fine particles 5 as described above, the generation of nodules due to electrostatic attraction due to the variation in the charging of the individual fine particles 5 is eliminated, and the uniform fine particles 5 having no nodules are formed. Can be sprayed. In the case of such static elimination, for example, when the substrate to be dispersed is a substrate such as a TFT array substrate of an active matrix type liquid crystal display device, when the charged fine particles 5 are dispersed on the substrate, the charge is transferred to the TFT array substrate side. Since it may move to cause electrostatic breakdown of the TFT, it is extremely effective in preventing such a bad influence on the substrate to be scattered by static electricity.

(Embodiment 4) In the first embodiment, an example in which a nodule of fine particles 5 is decomposed by using a mesh made of stainless steel as the filter 4 was introduced. However, the filter 4 was replaced with a gas permeable porous metal. By using this as an ion charge electrode, it is possible to effectively achieve the ion charge while individually decomposing the nodules of the fine particles 5, that is, an experiment using the filter 4 made of such a permeable porous metal material. Confirmed by the inventors.

In each of the above embodiments, the present invention has been described in the case where spacers such as microbeads are dispersed on the liquid crystal cell substrate of the liquid crystal display device. Is not limited to this. In addition to this, for example, it can be applied to a case where fine particles are scattered to form a reflector used for a road sign or the like. That is, by using the technique of the present invention, it is possible to uniformly disperse the fine particles for realizing the reflection function of the reflection plate without forming an agglomerate. As a result, it is possible to avoid the generation of unsightly reflection bright spot defects and the like that have occurred due to the particles becoming agglomerated. Conventionally, when forming a reflector used for road signs as described above,
The fine particles for realizing the reflection function are mixed in the paint and well stirred to avoid the formation of nodule. However, for example, when fine particles are mixed in a petroleum-based paint and stirred, the fine particles may be charged with static electricity and aggregate in a nodule shape. However, if the present invention is applied to this, the fine particles can be uniformly dispersed without forming a cluster.

The planar shape of the outer periphery of the holes of the filter may be a mesh shape as described above, but may be, for example, a circular shape or a regular polygonal shape.

In each of the above embodiments, the fine particles 5 are used.
When the spraying nozzle 3 blows out the particles 5 just below the nozzle.
However, it is needless to say that the structure and method of the device of the present invention are not limited to the above-mentioned embodiment. In addition to this, it goes without saying that the present invention can be applied to, for example, a method of pressure-feeding the fine particles 5 from the outside of the spraying tank 1.

Needless to say, the conditions such as the distance between the spray nozzle 3 and the filter 4 and the blowing amount can be changed.

In the above embodiment, the gas used for blowing out the fine particles 5 is N ₂ (dry nitrogen).
A general gas used for blowing out the fine particles 5 such as air or air can be used.

[0047]

As is clear from the detailed description above, according to the present invention, even when the spraying material powder originally agglomerated by moisture absorption, static electricity or the like is used, it is formed as a nodule on the object to be sprayed. It is possible to provide a fine particle spraying method and a fine particle spraying apparatus that can uniformly spray fine particles without being sprayed.

[Brief description of drawings]

FIG. 1 is a diagram showing an outline of a structure of a fine particle spraying device according to the present invention.

FIG. 2 is a diagram showing an effect of the present invention.

[Explanation of symbols]

 1 ... Spreading tank 2 ... Substrate which is the object to be spread 3 ... Spraying nozzle 4 ... Filter 5 ... Fine particles 6 ... Material powder loading plate 7 ... Ionizer

Claims (14)

[Claims] 1. A step of ejecting fine particles together with a gas from a blow-out port; and passing the fine particles through the holes of a filter having at least one hole, so that the fine particles aggregated in a nodule among the fine particles are removed. Separating the individual fine particles, charging the fine particles to the same polarity, and holding the fine particles in a separated state by the charged electric charge of the same polarity, the charged fine particles on the sprayed body A method for spraying fine particles, which comprises: 2. A step of ejecting a fine particle powder together with a gas from an outlet, and passing the fine particles through the holes of a filter having at least one hole, so that the fine particles are aggregated in a nodule shape. Separating the fine particles into individual fine particles and charging the fine particles to the same polarity; further charging the fine particles to the same polarity and holding the fine particles in a separated state by the charged electric charges of the same polarity. A method for spraying fine particles, comprising: a step; and a step of spraying the charged fine particles on an object to be sprayed. 3. A step of ejecting fine particles together with a gas from a blow-out port; and passing the fine particles through the holes of a filter having at least one hole, so that the fine particles aggregated in a nodule among the fine particles are removed. Separating the individual fine particles and charging the fine particles to the same polarity, and holding the fine particles in a separated state by the charged electric charges of the same polarity; and the fine particles charged by the filter on the object to be scattered. A method for spraying fine particles, which comprises: 4. A step of ejecting fine particles together with a gas from a blowout port; and passing the fine particles through the holes of a filter having at least one hole, to remove the fine particles that have been aggregated in the agglomerates. A step of separating each of the fine particles, a step of removing the charge of the fine particles, holding the fine particles in a separated state, and a step of spraying the charged fine particles on the object to be dispersed. A method of spraying fine particles. 5. The method for spraying fine particles according to claim 1, wherein the filter is provided with holes each having a size capable of passing one to three particles at a time. A method of spraying fine particles, characterized by using a filter. 6. The method for spraying fine particles according to any one of claims 1 to 3 and 5, wherein the filter has a positive charging order with respect to the fine particles, and the particles have a negative charge polarity when passing through the filter. A method for spraying fine particles, characterized in that the fine particles are further negatively charged by a charger while using a filter made of the material described above. 7. The method for spraying fine particles according to claim 1, wherein the filter has a negative charging order with respect to the fine particles, and the positive polarity of the fine particles is positive by passing through the filter. A fine particle spraying method, characterized in that the fine particles are further positively charged by a charger while using a filter made of the material described above. 8. A filter having an air outlet for ejecting fine particles together with a gas and at least one hole for separating fine particles, which are aggregated in agglomerates among the fine particles when passing through the fine particles, into individual fine particles. A charger for charging the fine particles to the same polarity, and a mounting table on which the object to be dispersed on which the fine particles are dispersed is placed,
A fine particle spraying device comprising: 9. An outlet for ejecting fine particles together with a gas, and fine particles that have aggregated in agglomerates among the fine particles when the fine particles pass through are separated into individual fine particles and the fine particles are charged to the same polarity. A filter in which at least one hole is opened, a charger that charges the fine particles to the same polarity, and a mounting table on which a sprayed body to which the fine particles are dispersed is mounted.
A fine particle spraying device comprising: 10. An outlet for ejecting fine particles together with a gas, and separates the fine particles, which have been aggregated in agglomerates when the fine particles pass through, into individual fine particles and charges the fine particles to the same polarity. A fine particle spraying device comprising: a filter having at least one hole formed therein; and a mounting table on which a sprayed body on which fine particles charged by the filter are sprayed is mounted. 11. A filter having an air outlet for ejecting fine particles together with a gas, and at least one hole for separating the fine particles that have been aggregated into aggregates into fine particles when the fine particles pass through. A static eliminator for removing static electricity of the fine particles, and a mounting table for mounting the sprayed body on which the fine particles are scattered,
A fine particle spraying device comprising: 12. The fine particle spraying device according to claim 8, wherein the filter is a filter having a plurality of holes each having a size capable of passing one to three fine particles at a time. A fine particle spraying device comprising: 13. The fine particle spraying device according to claim 8, wherein the filter has a negative charging order with respect to the fine particles, and the positive polarity of the fine particles is made positive by passing through the filter. A fine particle spraying device characterized by using a filter consisting of. 14. The fine particle spraying device according to claim 8, wherein the filter has a positive charging order with respect to the fine particles, and the negative polarity of the fine particles is caused by passing through the filter. A fine particle spraying device characterized by using a filter consisting of.