Production method of gelatinized material-containing coating

Abstract

To provide a production method of a gelatinized material-containing coating which can inexpensively produce a coating including a thin gelatinized material, with good productivity.SOLUTION: A production method of a gelatinized material-containing coating comprises: a step 1 for bringing an emulsion solution immediately after passing through a nozzle on which slits are formed, into contact with a gelatinization solution, for acquiring a fluid dispersion in which the gelatinized material is dispersed; and a step 2 for crushing by a crusher 10, the gelatinized material in the acquired fluid dispersion. The crusher 10 comprises: an input part casing 31 with a raw material supply hole 32; a screw 33 which is provided in the input part casing 31, and pushes forward, the fluid dispersion input from the raw material supply hole 32; and an outlet cutter 52 and a porous plate 54 which are sequentially provided in front of the screw 33.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a method for producing a gelled product-containing paint.

Background Art

[0002] In many cases, painting for the purpose of protection, decoration, etc. is applied to the surface of an object such as a wall material. As the paint used for painting, a paint in which gelled colored particles obtained by encapsulating an emulsion paint with a gelled film are dispersed in a dispersion medium is used. Emulsion paints belong to water-based paints and have high environmental compatibility compared to conventional solvent-based paints. Further, by encapsulating the emulsion paint with a gelled film, the colored particles are stably dispersed in the dispersion medium. Therefore, if several types of emulsion paints are used, a multicolor pattern paint in which colored particles having different color tones are mixed can be obtained, and a multicolor pattern coating film can be formed.

[0003] As a method for producing a paint containing gelled colored particles, for example, in Patent Document 1, an emulsion paint containing a resin emulsion, a coloring pigment, and a hydrophilic colloid-forming substance is added to a dispersion medium containing a gelling agent, and after gelling the surface of the emulsion paint, while stirring with a disperser such as a dissolver, an emulsion paint (gelled product) having a gelled surface is subdivided to produce gelled colored particles.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The gel-like colored particles are basically granular although amorphous, and have a certain three-dimensional shape. Therefore, it also contributes to the improvement of the design of the coating film coated therewith. However, having a three-dimensional shape means a large volume, which is one of the causes of high cost. Particularly, when gel-like colored particles of each color were mixed to form a multicolored pattern paint, high cost was likely to occur.

[0006] For cost reduction, it is desirable that the gel-like colored particles be flat and thin. However, as in Patent Document 1, it was difficult to obtain flat gel-like colored particles by a method of subdividing a gelled product while stirring with a blade rotating by a dissolver or the like. Therefore, an object of the present invention is to provide a method for producing a gelled product-containing paint that can produce a paint containing a thin gelled product with high productivity and at low cost.

Means for Solving the Problems

[0007] In order to solve the above problems, the present invention employs the following configuration. [1] Step 1 of obtaining a dispersion liquid in which a gelled product is dispersed by bringing an emulsion solution immediately after passing through a slit into contact with a gelling agent solution; Step 2 of crushing the gelled product in the obtained dispersion liquid with a crushing device, and The gelling agent solution contains at least a gelling agent, The emulsion solution contains at least a colloid-forming substance and a resin, The crushing device includes a casing having a raw material supply port, a screw provided inside the casing for pushing the dispersion liquid introduced from the raw material supply port forward, and a rotary cutter and a perforated plate sequentially provided in front of the screw, a method for producing a gelled product-containing paint. [2] The method for producing a gelled product-containing paint according to [1], wherein Step 1 is performed in a state where the end of the slit is disposed directly above the gelling agent solution. [3] The method for producing a gelled product-containing paint according to [1] or [2], wherein the emulsion solution contains at least one selected from colored pigments, pearlescent pigments, aggregates, and matting agents. [4] The method for producing a gelled product-containing paint according to any one of [1] to [3], wherein the width of the slit is 0.05 mm to 0.5 mm.

Advantages of the Invention

[0008] According to the method for producing a gelled product-containing paint of the present invention, a paint containing a gelled product with a thin thickness can be produced with high productivity and at low cost.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0010] In this specification and the claims, "~" indicating a numerical range means including the numerical values described before and after it as the lower limit value and the upper limit value. In addition, the term "flake-shaped" means a flat and thin shape having a first surface and a second surface facing each other and an aspect ratio of 2 or more. The aspect ratio can be obtained by (major axis ÷ thickness). The major axis in the case of a flake shape means the longer of the distances between the two most separated points on the outer periphery of the first surface and the distances between the two most separated points on the outer periphery of the second surface. The thickness in the case of a flake shape means the distance between the most separated parts of the first surface and the second surface.

[0011] The manufacturing method of the gelled product-containing paint of this aspect includes Step 1 of bringing the emulsion solution immediately after passing through a slit into contact with a gelling agent solution to obtain a dispersion liquid in which the gelled product is dispersed, and Step 2 of crushing the gelled product in the obtained dispersion liquid with a crushing device.

[0012] <Step 1> Step 1 is a step of bringing the emulsion solution immediately after passing through a slit into contact with a gelling agent solution to obtain a dispersion liquid in which the gelled product is dispersed. Bringing the emulsion solution immediately after passing through a slit into contact with the gelling agent solution means that the emulsion solution comes into contact with the gelling agent solution at the moment when it is discharged from the slit.

[0013] The emulsion solution comes into contact with the gelling agent solution at the moment when it is discharged from the slit, and the surface gels to become a gelled product. A dispersion liquid in which the gelled product is dispersed in the gelling agent solution is obtained. The gelled product in the obtained dispersion liquid is in the form of a strip because the surface of the emulsion solution discharged from the slit gels.

[0014] [Dispersion liquid preparation device] Fig. 1 shows a dispersion liquid preparation device 1 as an example of the device used in Step 1. The dispersion liquid preparation device 1 in Fig. 1 includes a nozzle 2, a storage tank 3 storing the emulsion solution, a recovery tank 4 storing the gelling agent solution, a pipe 5 for supplying the emulsion solution stored in the storage tank 3 to the nozzle 2, and a pump 6 provided in the middle of the pipe 5.

[0015] A slit is formed in the nozzle 2, and its tip is arranged above the gelling agent solution stored in the recovery tank 4. By operating the pump 6, the emulsion solution stored in the storage tank 3 passes through the slit of the nozzle 2. Since the tip of the nozzle 2, that is, the end of the slit, is arranged directly above the gelling agent solution, the emulsion solution comes into contact with the gelling agent solution immediately after passing through the slit of the nozzle 2. As a result, a strip-shaped gelled product is extruded and dispersed in the gelling agent solution.

[0016] The thickness of the strip-shaped gelled product is defined by the slit width of nozzle 2. The specific slit width of nozzle 2 may be appropriately adjusted according to the thickness of the gelled product in the gelled product-containing paint obtained in this embodiment, but it is preferably 0.05 to 0.5 mm, and more preferably 0.1 to 0.3 mm. Note that since the gelled product in the dispersion obtained in step 1 is crushed in the subsequent step 2, the thickness of the gelled product in the gelled product-containing paint obtained in this embodiment is slightly thinner than the slit width of nozzle 2.

[0017] The width of the strip-shaped gelled product is defined by the length of the slit of nozzle 2 (the length at the outlet). There is no particular limitation on the length of the slit, but considering the convenience of handling the dispersion liquid, etc., it is preferably 30 to 150 mm, and more preferably 50 to 100 mm. Note that since the gelled product in the dispersion obtained in step 1 is crushed in the subsequent step 2, the major axis of the gelled product in the gelled product-containing paint obtained in this embodiment is much smaller than the length of the slit of nozzle 2.

[0018] Nozzle 2 is not particularly limited in its specific shape as long as at least a slit is formed at the outlet. However, since it is easy to stably pass a slit of a desired width, it is preferable that a slit having a length along the discharge direction is formed. The length along the discharge direction is preferably 10 to 100 mm, and more preferably 30 to 80 mm. If the length along the discharge direction is equal to or greater than the lower limit value of the preferable range, it is easy to stably pass a slit of a desired width. If it is equal to or less than the upper limit value of the preferable range, it can be discharged from the slit without applying high pressure to the emulsion solution.

[0019] A nozzle having a slit with a length along the ejection direction can be configured, for example, by using the gap between two metal plates as the slit and hermetically joining both ends using a gasket or the like. Alternatively, it can be configured by using the gap between the bent portions of a single metal plate as the slit and hermetically joining one end. Examples of a nozzle having a slit only at the outlet include a configuration in which an outlet plate having a slit is provided at the tip of a flat nozzle.

[0020] There may be a plurality of slits formed in the nozzle 2. By arranging a plurality of slits in proximity and supplying emulsion solutions of different colors to each slit, paints of a plurality of colors are laminated, and a band-shaped gelled product having a complex color tone can be obtained. The pump 6 may be operated continuously or intermittently. Also, a shut-off cock may be provided in the middle of the pipe 5. By operating the pump 6 intermittently or opening and closing the shut-off cock, it is possible to avoid the band-shaped gelled product from becoming too long.

[0021] The dispersion preparation device used in Step 1 is not limited to the dispersion preparation device 1 shown in FIG. 1. For example, like the device disclosed as FIG. 1 of Japanese Patent Application No. 2015-81283, a double nozzle may be used to eject an emulsion solution from the inner nozzle (the one having a slit) and eject a gelling agent solution from the outer nozzle so that the two liquids come into contact immediately after being ejected from the nozzles.

[0022] [Emulsion solution] The emulsion solution used in Step 1 contains at least a colloid-forming substance and a resin. Moreover, it preferably contains at least one selected from coloring pigments, pearlescent pigments, aggregates, and matting agents.

[0023] The colloidal forming substance may be any substance that can react with the gelling agent to form a gelling film. Examples of the colloidal forming substance include, for example, aqueous solutions containing cellulose derivatives; polyethylene oxide; polyvinyl alcohol; natural polymers such as casein, starch, galactomannan, guar gum, locust bean gum, etc. Among them, an aqueous solution of guar gum is preferred. When using an aqueous solution of guar gum, the concentration of the aqueous solution is preferably 0.5 to 5% by mass, more preferably 1.0 to 3% by mass.

[0024] These colloidal forming substances may be used alone or in combination of two or more. The content (dry solid) of the colloidal forming substance is preferably 0.05 to 5 parts by mass, more preferably 0.1 to 3.0 parts by mass with respect to 100 parts by mass of the resin emulsion. If the content of the colloidal forming substance is within the above range, a stable gelling film can be easily obtained.

[0025] Examples of the resin include polyvinyl acetate, acrylic resin, polystyrene, acrylonitrile, veova (vinyl ester of branched fatty acid), natural or synthetic rubber, and copolymers thereof. Generally, resins commercially available as resin emulsions can be used. Among them, acrylic resin is preferred. Since the emulsion solution contains resin, a gelled product with a shape that is not easily deformed during coating can be obtained.

[0026] By containing at least one selected from coloring pigments, lustrous pigments, aggregates, and matting agents, the emulsion solution can exhibit design properties such as coloring and glossiness. Examples of the coloring pigment include inorganic pigments such as carbon black, titanium oxide, iron oxide, lead chromate, cadmium yellow, cadmium red, etc.; organic pigments such as phthalocyanine blue, phthalocyanine green, quinacridone red, etc. These coloring pigments may be used alone or in combination of two or more.

[0027] The average particle diameter of the coloring pigment is preferably 40 μm or less, more preferably 20 μm or less. When the average particle diameter of the coloring pigment is below the upper limit value, it is easy to stably disperse in the dispersion medium, and the emulsion solution is smoothly discharged from the slit. The average particle diameter of the coloring pigment is the value of the median diameter (50% cumulative particle diameter) calculated from the volume average diameter measured by the laser diffraction / scattering method.

[0028] Examples of the bright pigment include pearl pigment, mica pigment, mica-coated pearl pigment, aluminum powder, stainless steel powder, and the like. The average particle diameter of the bright pigment is preferably 80% or less of the slit thickness, more preferably 60% or less. If the average particle diameter of the bright pigment exceeds the preferable upper limit value, the bright pigment may clog the slit. When the average particle diameter of the bright pigment is below the upper limit value, the emulsion solution is smoothly discharged from the slit. The average particle diameter of the bright pigment is the value of the median diameter (50% cumulative particle diameter) calculated from the volume average diameter measured by the laser diffraction / scattering method.

[0029] The content of at least one selected from the coloring pigment, bright pigment, aggregate, and matting agent is not particularly limited, but is preferably 0.01 to 50% by mass, more preferably 0.1 to 30% by mass, based on the total amount of the emulsion solution. The emulsion solution may optionally contain extender pigments and known additives (such as thickeners, dispersants, defoamers, preservatives, leveling agents, etc.) as optional components.

[0030] Extender pigments are a general term for achromatic pigments used in paints. Examples of extender pigments include kaolin, barium sulfate, hydrated magnesium silicate, calcium carbonate, and the like. These extender pigments may be used alone or in combination of two or more. The content of the extender pigment is preferably 0 to 30% by mass, more preferably 0 to 20% by mass, in 100% by mass of the emulsion solution.

[0031] The dispersion medium of the emulsion solution is only water or an aqueous medium obtained by adding a solvent compatible with water to water. The proportion of water in the aqueous medium is preferably 50% by mass or more, more preferably 70% by mass or more, and even more preferably 90% by mass or more. As the water, ion-exchanged water, tap water, etc. can be used. Examples of the solvent compatible with water include alcohols such as ethanol and isopropyl alcohol, and ethylene glycol.

[0032] The emulsion solution is obtained by adding a colloidal forming substance to the emulsion of the above resin, stirring and mixing, and then adding a coloring pigment, etc. and an aqueous medium and further stirring and mixing. The content of the aqueous medium is preferably 40 - 90% by mass, more preferably 50 - 80% by mass in 100% by mass of the emulsion solution.

[0033] [Gelling agent solution] The gelling agent solution used in Step 1 contains at least a gelling agent. The gelling agent forms a gelled film containing a three-dimensional network structure by reacting with and crosslinking the colloidal forming substance.

[0034] Examples of the gelling agent include aqueous solutions containing magnesium montmorillonite clay, sodium pentachlorophenol, borate, tannic acid, titanium lactate, calcium chloride, sodium hydroxide, etc. Among them, an aqueous solution of borate is preferred. These gelling agents may be used alone or in combination of two or more.

[0035] The content of the gelling agent (dry solid content) is not particularly limited, but in the case of borate, it is preferably 0.05 - 10% by mass, more preferably 0.05 - 8% by mass in 100% by mass of the gelling agent solution. In the case of calcium chloride, it is preferably 0.1 - 10% by mass, more preferably 0.5 - 8% by mass in 100% by mass of the gelling agent solution. If the content of the gelling agent is within the above range, a stable gelled film is likely to be obtained.

[0036] The gelling agent solution may contain, as optional components, extender pigments, water-soluble polymer compounds, and known additives, as necessary. Examples of extender pigments include those exemplified above in the description of emulsion paints. Among them, magnesium metasilicate hydrate is preferable. The extender pigment may be used alone or in combination of two or more. The content of the extender pigment is preferably 0.05 to 10% by mass, more preferably 0.1 to 5% by mass, in 100% by mass of the gelling agent solution.

[0037] Examples of water-soluble polymer compounds include aqueous solutions containing hydroxyethyl cellulose, carboxymethyl cellulose, methyl cellulose, polyvinyl alcohol, and the like. Among them, an aqueous solution of carboxymethyl cellulose or methyl cellulose is preferable. These water-soluble polymer compounds may be used alone or in combination of two or more. The content of the water-soluble polymer compound is preferably 0.05 to 3% by mass, more preferably 0.1 to 2% by mass, in 100% by mass of the gelling agent solution.

[0038] Examples of additives include those exemplified above in the description of emulsion paints. As the dispersion medium of the gelling agent solution, water or an aqueous medium in which a solvent compatible with water is added to water can be used, similar to the dispersion medium in emulsion paints.

[0039] The gelling agent solution is obtained by adding water to a stirred mixture of an aqueous solution containing a gelling agent, a dispersion liquid containing an extender pigment as necessary, an aqueous solution containing a water-soluble polymer compound, etc., for dilution. The content of the aqueous medium is preferably 20 to 80% by mass, more preferably 30 to 70% by mass, in 100% by mass of the gelling agent solution.

[0040] <Step 2> Step 2 is a step of crushing the gelled product in the dispersion obtained in Step 1 with a crushing device. The gelled product in the dispersion obtained in Step 1 is in a strip shape, but by being crushed in Step 2, it becomes a flaky (which can also be described as scaly, flat, plate-shaped, or sheet-like) gelled product.

[0041] [Crushing device] Fig. 2 shows a crushing device 10 as an example of the device used in Step 2. The crushing device 10 in Fig. 2 is generally composed of a drive unit 20, a feeding unit 30, a crushing unit 40, and a transfer unit 50. A support 61 is provided at a position supporting near the starting ends of the drive unit 20 and the feeding unit 30, a support 62 is provided on the terminal side of the feeding unit 30, a support 63 is provided on the terminal side of the crushing unit 40, and a support 64 is provided on the terminal side of the transfer unit 50, respectively.

[0042] The drive unit 20 has a rotation motor 21, a main drive shaft 22 that rotates as the rotation motor 21 rotates, and an eccentric drive shaft 23 connected to the tip of the main drive shaft 22. The main drive shaft 22 is inserted from the feeding unit 30 to the terminal side of the crushing unit 40. Also, the eccentric drive shaft 23 is inserted from the terminal side of the crushing unit 40 to the terminal side of the transfer unit 50. That is, the feeding unit 30, the crushing unit 40, and the transfer unit 50 communicate with each other.

[0043] The feeding unit 30 has a feeding unit casing 31, a screw 33, and a filter 34. The feeding unit casing 31 is generally composed of a substantially semi-cylindrical casing body 31a, a square tube portion 31b continuing from the upper side thereof, and a flange portion 31c provided around the upper end of the square tube portion 31b. At the upper end of the square tube portion 31b, a rectangular raw material supply port 32 is open. The cross-section of the feeding unit casing 31 seen from the left side in the figure is U-shaped. At the terminal end (left end in the figure) of the feeding unit casing 31, a circular opening (not shown in detail) communicating with the crushing unit 40 is formed.

[0044] The filter 34 is disposed at the boundary portion with the crushing section 40 so as to close an opening formed at the end of the input section casing 31. A through hole (not shown) through which the main drive shaft 22 passes is provided at the center of the filter 34, and this portion serves as a bearing for the main drive shaft 22. Also, a plurality of communication holes (not shown) for allowing the object to be processed to pass from the input section 30 to the crushing section 40 side are formed around the through hole serving as the bearing.

[0045] The screw 33 is fixed to the main drive shaft 22 inside the input section casing 31, and rotates as the rotation motor 21 rotates, so as to send the object to be processed input to the input section casing 31 to the end side (left side in the figure). In this embodiment, the end of the screw 33 is in contact with the filter 34.

[0046] The crushing section 40 is in front of the input section 30 and has a crushing section casing 41 and a crushing cutter 42. The crushing section casing 41 is cylindrical, and a communication hole 43 is formed at the center of the end side thereof to allow the eccentric drive shaft 23 to be inserted therethrough and to allow the object to be processed to pass to the transfer section 50 side. The eccentric drive shaft 23 is connected to the main drive shaft 22 at a slightly rear end side (right side in the figure) of the communication hole 43.

[0047] The crushing cutter 42 is fixed to the main drive shaft 22 near the input section 30, and rotates as the rotation motor 21 rotates, so as to roughly cut the object to be processed extruded from the input section 30. The mode of the crushing cutter 42 is not particularly limited. For example, the outlet cutter 52 described later with a slightly larger size can be used.

[0048] The transfer section 50 is further in front of the crushing section 40 and has a transfer section casing 51, an outlet cutter 52, and a perforated plate 54. The transfer section casing 51 is cylindrical with a smaller diameter than the crushing section casing 41. The perforated plate 54 is attached to the end of the transfer section casing 51.

[0049] The outlet cutter 52 is attached to the end of the eccentric drive shaft 23. That is, in front of the screw 33 of the input section 30, the outlet cutter 52 and the perforated plate 54 are sequentially provided. The outlet cutter 52 is a rotary cutter that rotates eccentrically as the rotary motor 21 rotates. The outlet cutter 52 contacts the perforated plate 54 and rotates while rubbing against the perforated plate 54.

[0050] There is no particular limitation on the specific form of the outlet cutter 52. For example, as shown in FIG. 3, it can be a cross cutter having four cutter blades 53. There is no particular limitation on the specific form of the perforated plate 54. For example, as shown in FIG. 4, a perforated plate having a large number of gel extrusion holes 55 formed in the portion where the outlet cutter 52 contacts can be used. As shown in FIG. 4, a packing 56 is provided around the periphery where the gel extrusion holes 55 of the perforated plate 54 are formed, and the perforated plate 54 is attached to the end of the transfer section casing 51 in a watertight manner.

[0051] The diameter of the gel extrusion hole 55 may be appropriately set in consideration of the major axis length of the gelled product in the gelled product-containing paint obtained in this embodiment, but it is preferably 1 to 10 mm, and more preferably 2 to 8 mm. The major axis length of the gelled product in the gelled product-containing paint obtained in this embodiment is substantially equal to the diameter of the gel extrusion hole 55.

[0052] In addition, if the gelled product (strip-shaped) in the dispersion liquid obtained in Step 1 is short, the crushing cutter 42 in the crushing section 40 can be omitted. Further, the tip of the screw 33 of the input section 30 does not have to contact the filter 34. A plurality of crushing cutters 42 in the crushing section 40 may be provided as necessary.

[0053] In addition, in this embodiment, the outlet cutter 52 is eccentrically rotated using the eccentric drive shaft 23, but eccentric rotation is not essential. Further, although the outlet cutter 52 preferably contacts the perforated plate 54 as in the present embodiment, it may be somewhat spaced apart.

[0054] [Crushing] Step 2 is performed by introducing the dispersion obtained in Step 1 from the raw material supply port 32 of the crushing device 10 and subjecting it to a crushing process by the crushing device 10. When the dispersion is introduced into the charging section 30 from the raw material supply port 32, the screw 33 in the charging section 30 transfers the dispersion forward (left side in the figure) together with the gelled material being dispersed.

[0055] The transferred dispersion is pushed out from the charging section 30 to the crushing section 40 through the communication holes of the filter 34. At this time, since the tip of the screw 33 contacts the filter 34, the strip-shaped gelled material is pushed out while being sandwiched between the screw 33 and the filter 34, and is cut to some extent.

[0056] The gelled material pushed into the crushing section 40 is further roughly cut by the crushing cutter 42. Therefore, even if the gelled material (strip-shaped) in the dispersion obtained in Step 1 is long, it can be smoothly transferred to the end of the transfer section 50.

[0057] When the transferred dispersion reaches the end of the transfer section 50, the outlet cutter 52 cuts while pressing the gelled material in the dispersion against the perforated plate 54, and pushes it out from the gel extrusion holes 55 of the perforated plate 54. Therefore, there is no entanglement such that the strip-shaped gelled material winds around the rotating shaft as in the case of using a disperser with only a blade attached to the rotating shaft, and a paint containing a gelled material can be produced with high productivity. In addition, since the gelled material in the dispersion is already in a flat strip shape before crushing, by being crushed in Step 2, it becomes a thin flake-shaped gelled material instead of a three-dimensional granular shape. The paint containing the gelled material in which the flake-shaped gelled material is dispersed is recovered from the gel extrusion holes 55.

[0058] In step 2, a plurality of gelled products with different color tones may be charged at once and subdivided together, or they may be subdivided separately for each color and then mixed. Also, after step 2, any component may be further added as long as the effects of the present invention are not impaired.

[0059] <Paint containing gelled product> The paint containing gelled product obtained by the production method of the present embodiment is a paint in which flaky gelled products are dispersed in a dispersion medium. The average value of the major axis of the gelled product contained in the paint containing gelled product is preferably 500 μm or more, more preferably 1,000 μm or more. Also, it is preferably 10 mm or less, more preferably 8 mm or less.

[0060] The average value of the thickness of the gelled product contained in the paint containing gelled product is preferably 5 μm or more, more preferably 50 μm or more, and most preferably 100 μm or more. Also, it is preferably 1,000 μm or less, more preferably 500 μm or less, and most preferably 300 μm or less.

[0061] The average value of the aspect ratio (average value of the major axis ÷ average value of the thickness) of the gelled product contained in the paint containing gelled product is 2 or more, preferably 2 to 500, and more preferably 5 to 200. When the average value of the aspect ratio is equal to or greater than the preferred lower limit value, the adhesion of the gel-like particles to the substrate is improved, and the color possessed by the gel-like particles is likely to be reflected in a wide range of coating films. When the average value of the aspect ratio is equal to or less than the preferred upper limit value, the strength of the flaky gelled product can be ensured.

[0062] The average value of the major axis and the average value of the thickness of the gelled product are values obtained by randomly taking out 20 gelled products in the aqueous paint and calculating the arithmetic mean of each measured value measured with a ruler or a microscope. The shape of the gelled product in plan view is not particularly limited, but according to the production method of this embodiment, it is likely to be amorphous.

Examples

[0063] Hereinafter, the present invention will be described more specifically based on examples, but the present invention is not limited to these examples. In the examples, "parts" means "parts by mass" and "%" means "% by mass".

[0064] <Production of Emulsion Solution> 38 parts of an acrylic resin emulsion (manufactured by Nippon Acrylic Chemical Co., Ltd., "Primal (registered trademark) AC-38") and 28.5 parts of a 1.5% aqueous solution of a nonionic guar gum derivative (solid content 0.43 part) were mixed to prepare a mixed solution (a). Separately, 10 parts of titanium white as a coloring pigment, 1 part of an anionic polymer dispersant (manufactured by Nippon Acrylic Chemical Co., Ltd., "Orotan (registered trademark) 731"), and 22.5 parts of water were mixed to prepare a mixed solution (b). The mixed solution (b) was added to the mixed solution (a) and stirred to obtain an emulsion paint.

[0065] <Production of Gelator Solution> To 25 parts of a 4% aqueous dispersion of magnesium silicate hydrate (solid content 1 part), 5 parts of a 5% aqueous solution of ammonium borate (solid content 0.25 part) and 25 parts of a 1% aqueous solution of sodium carboxymethyl cellulose (solid content 0.25 part) were added and stirred and mixed, and then 45 parts of water was added for dilution to obtain a dispersion medium.

[0066] <Dispersion Preparation Apparatus> A dispersion preparation apparatus having the same configuration as the dispersion preparation apparatus 1 in schematic diagram 1 was used. As the nozzle 2, a metal plate with a length of 10 cm in the discharge direction was folded, and a slit with a width of 0.5 mm and a length of 100 mm was formed in the folded gap. This nozzle 2 was set so that the tip was disposed directly above the gelator solution in the recovery tank 4.

[0067] <Crushing Device> For the crushing treatment, an apparatus equivalent to that in FIG. 2 was used. The dimensions of each part of the used crushing device are as follows. Inner diameter of the charging part casing 31: 7 cm. Inner length of the charging part casing 31: 33 cm. Inner diameter of the crushing section casing 41: 7 cm. Length inside the crushing section casing 41: 30 cm. Inner diameter of the transfer section casing 51: 5 cm. Length inside the transfer section casing 51: 30 cm. Diameter of the communication holes of the filter 34: 1.5 cm. Number of the communication holes of the filter 34: 8. Diameter of the gel extrusion holes 55 of the perforated plate 54: 0.5 cm.

[0068] <Disperser> A high-shear type stirrer manufactured by Asada Iron Works Co., Ltd. was used.

[0069] <Example 1> Using the dispersion liquid preparation device, the emulsion solution prepared above was discharged into 20 L of the gelling agent solution prepared above at a flow rate of 1 kg / min for 5 minutes to obtain a dispersion liquid. The total amount of the obtained dispersion liquid was put into the crushing device for crushing treatment, and the paint discharged from the perforated plate 54 was used as the paint of Example 1.

[0070] <Example 2> The total amount of the paint recovered in the same manner as in Example 1 was put into the crushing device again for crushing treatment, and the paint discharged from the perforated plate 54 was used as the paint of Example 2.

[0071] <Example 3> The total amount of the paint recovered in the same manner as in Example 2 was put into the crushing device again for crushing treatment, and the paint discharged from the perforated plate 54 was used as the paint of Example 3.

[0072] <Comparative Example 1> The total amount of the dispersion liquid obtained in the same manner as in Example 1 was treated with a disperser for 10 minutes, and the obtained paint was used as the paint of Comparative Example 1.

[0073] <Comparative Example 2> The total amount of the dispersion liquid obtained in the same manner as in Example 1 was treated with a disperser for 20 minutes, and the obtained paint was used as the paint of Comparative Example 2.

[0074] <Comparative Example 3> 12 L of the emulsion solution prepared above and 8 L of the gelling agent solution prepared above were mixed and treated with a disperser for 20 minutes, and the resulting paint was used as the paint of Comparative Example 3.

[0075] Fifteen gelated products were randomly taken out from the paints of each example. The taken-out particles were each dried on a release paper, encapsulated with an epoxy resin, polished along the thickness direction with a polishing machine, and the cross-section was observed with a microscope, and the thickness and major diameter were measured. Table 1 shows the maximum and minimum values of the thickness and major diameter of the 15 gelated products, as well as the averaged results, for each example.

[0076] [Table 1]

[0077] As shown in Table 1, in each example, thin flaky gelated products were obtained. In particular, the thickness could be reduced as the number of crushing treatments in Step 2 was increased. Also, there were no particular problems with the paint productivity. On the other hand, in the comparative examples using a disperser, belt-shaped gelated products were entangled around the rotation axis, resulting in poor productivity, and the gelated products in the obtained paint were not so finely divided. In Comparative Example 3 where subdivision was directly performed with a disperser without passing through a slit, thick and three-dimensional gelated products were obtained, which was disadvantageous in terms of cost reduction. [Explanation of Signs]

[0078] 1 Dispersion preparation device 2 Nozzle 3 Storage tank 4 Recovery tank 5 Pipe 6 Pump 10 Crushing device 20 Driving unit 21 Rotation motor 22 Main drive shaft 23 Eccentric drive shaft 30 Input section 31 Input section casing 32 Raw material supply port 33 Screw 34 Filter 40 Crushing section 41 Crushing section casing 42 Crushing cutter 50 Transfer section 51 Transfer section casing 52 Outlet cutter 53 Cutter blade 54 Perforated plate 55 Gel extrusion hole 56 Packing

Claims

1. Step 1 of obtaining a dispersion liquid in which a gelled product is dispersed by bringing an emulsion solution immediately after passing through a slit into contact with a gelling agent solution; Step 2 of crushing the gelled product in the obtained dispersion liquid with a crushing device; The gelling agent solution contains at least a gelling agent; The emulsion solution contains at least a colloid-forming substance and a resin; The crushing device includes a casing having a raw material supply port, a screw provided inside the casing for pushing forward the dispersion liquid introduced from the raw material supply port, and a rotary cutter and a perforated plate sequentially provided in front of the screw, and is a method for producing a paint containing a gelled product.

2. The method for producing a paint containing a gelled product according to Claim 1, wherein Step 1 is performed in a state where the end of the slit is disposed directly above the gelling agent solution.

3. The method for producing a paint containing a gelled product according to Claim 1 or 2, wherein the emulsion solution contains at least one selected from a coloring pigment, a pearlescent pigment, an aggregate, and a matting agent.

4. The method for producing a paint containing a gelled product according to Claim 1 or 2, wherein the width of the slit is 0.05 mm to 0.5 mm.

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