Coated flake-like glass and resin composition

Abstract

To provide coated flaky glass that is used as a filler for reinforcing a resin molding and suitable for suppressing the degradation of matrix resin while maintaining its functionality as a filler, and also to inhibit the degradation of matrix resin in a resin molding.SOLUTION: Coated flaky glass includes flaky glass, and a surface treatment agent that covers at least part of the surface of flaky glass. In the coated flaky glass, the content of the surface treatment agent is 5 mass% or more and less than 10 mass%. A resin composition includes matrix resin and the coated flaky glass.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to coated flaky glass and a resin composition.

Background Art

[0002] It is generally known that in resin molded articles, flaky base materials such as glass fibers, carbon fibers, glass beads, flaky glass, mica, talc and the like are blended as fillers into a matrix resin for the purposes of reducing warpage and deformation and / or improving mechanical strength, etc.

[0003] For example, Patent Document 1 proposes a glass-reinforced resin composition comprising a thermoplastic resin, glass flakes having an average thickness of 0.2 to 0.7 µm, and a surface treatment deactivator, wherein the amount of the surface treatment agent for the glass flakes is 1.5 to 5 parts by weight relative to 100 parts by weight of the glass flakes. In addition, Patent Document 2 discloses a granular flaky glass comprising flaky glass having an average thickness of 0.1 to 2.0 µm and an average particle diameter of 10 to 2000 µm, and a binder that granulates the flaky glass, wherein the solid content mass ratio of the binder in the granular flaky glass is in the range of 1.0 mass% to 5.0 mass%, and the binder contains a coupling agent in a range of 9 mass% or less. Said granular flaky glass and a resin composition using the same are proposed.

Prior Art Literature

Patent Literature

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problem to be Solved by the Invention

[0005] Some resins, particularly thermoplastic resins, are susceptible to decomposition by alkaline components. When such resins are used as the matrix resin for molded products, the alkaline components in the flake-like glass can cause the resin to decompose, leading to a decrease in the mechanical properties and appearance of the molded product. To suppress the decomposition of the matrix resin, methods involving the addition of stabilizers or antioxidants have been proposed. Examples of stabilizers include phosphorus-based and lactone-based stabilizers. Examples of antioxidants include hindered phenol compounds and phosphite compounds. However, adding too much stabilizer or antioxidant can degrade the mechanical properties of the molded product. Furthermore, the stabilizer or antioxidant may migrate to the surface of the matrix resin, resulting in so-called blooming or bleeding.

[0006] One of the objectives of the present invention is to provide a coated flake-like glass suitable for suppressing the decomposition of the matrix resin while maintaining its function as a filler when used as a filler to reinforce a resin molded product. Another objective of the present invention is to suppress the decomposition of the matrix resin in a resin molded product. [Means for solving the problem]

[0007] From one aspect, the present invention, Flake-shaped glass and, A surface treatment agent that covers at least a portion of the surface of the flake-like glass, A coated flake-like glass containing, The content ratio of the surface treatment agent in the coated flake-like glass is 5% by mass or more and less than 10% by mass. We provide coated flake-like glass.

[0008] From another aspect, the present invention Matrix resin and The above-mentioned coated flake-like glass of the present invention, including, A resin composition is provided. [Effects of the Invention]

[0009] According to the present invention, when used as a filler to reinforce a resin molded product, it is possible to provide a coated flake-like glass suitable for suppressing the decomposition of the matrix resin while maintaining its function as a filler, and furthermore, it is possible to suppress the decomposition of the matrix resin in the resin molded product. [Brief explanation of the drawing]

[0010] [Figure 1] This is a schematic diagram illustrating an example of a manufacturing apparatus for flake-shaped glass. [Figure 2] This is a schematic diagram illustrating another example of a manufacturing apparatus for flake glass. [Modes for carrying out the invention]

[0011] The following describes specific embodiments of the coated flake glass and resin composition of the present invention, but the following description is not intended to limit the present invention to any particular embodiment.

[0012] [Coated flake-like glass] The coated flake glass of this embodiment comprises flake glass and a surface treatment agent that covers at least a portion of the surface of the flake glass. The content of the surface treatment agent in the coated flake glass of this embodiment is 5% by mass or more and less than 10% by mass.

[0013] The coated flake glass of this embodiment contains a surface treatment agent that covers at least a portion of the surface of the flake glass as described above. The content of the surface treatment agent in the coated flake glass is 5% by mass or more and less than 10% by mass. A surface treatment agent content of 5% by mass or more provides sufficient suppression of the decomposition of the matrix resin. A surface treatment agent content of less than 10% by mass avoids a decrease in the dispersibility of the flake glass due to excessive surface treatment agent. Therefore, because the surface treatment agent content of the coated flake glass of this embodiment is within the above range, when used as a filler to reinforce a resin molded product, it can suppress the decomposition of the matrix resin while maintaining its function as a filler. As a result, it is also possible to reduce the amount of stabilizers or antioxidants added. Thus, the coated flake glass of this embodiment can suppress the deterioration of the mechanical properties and appearance of the resulting resin molded product.

[0014] The content ratio of the surface treatment agent in the coated flake-shaped glass of this embodiment may be 5% by mass or more and 8% by mass or less.

[0015] The flake-like glass contained in the coated flake-like glass of this embodiment may have an average thickness of 0.1 to 1.0 μm and an average particle size of 0.1 to 2000 μm.

[0016] The average thickness of the flake glass contained in the coated flake glass of this embodiment may be in the range of 0.1 to 1.0 μm, as described above. The average thickness may also be in the range of 0.5 to 1.0 μm. In this specification, the average thickness of the flake glass can be calculated, for example, by measuring the thickness of 100 or more flake glass pieces using a scanning electron microscope (SEM) and dividing the total thickness by the number of pieces measured.

[0017] The average particle diameter of the flaky glass contained in the coated flaky glass of the present embodiment may be within the range of 0.1 to 2000 µm as described above. The average particle diameter may be 1.0 µm or more, 10 µm or more, further 100 µm or more, for example, within the range of 100 to 300 µm. The average particle diameter may be 200 µm or less. In the present specification, the average particle diameter of flaky glass refers to the particle diameter (D50) corresponding to 50% cumulative volume from the smaller particle diameter side in the particle size distribution of flaky glass measured based on the laser diffraction / scattering method.

[0018] The surface treatment agent contained in the coated flaky glass of the present embodiment includes, for example, at least one selected from the group consisting of a binder component and a silane coupling agent.

[0019] The binder component contained in the surface treatment agent is not particularly limited, and any known binder component used for surface treatment of flaky glass can be appropriately used. Examples of organic binder components include methyl cellulose, carboxymethyl cellulose, starch, carboxymethyl starch, hydroxyethyl cellulose, hydroxypropyl cellulose, polyvinyl alcohol, acrylic resins, epoxy resins, epoxy-modified polyolefin resins, phenolic resins, vinyl acetate, urethane resins, and the like. Examples of inorganic binder components include water glass, colloidal silica, colloidal alumina, and the like.

[0020] Furthermore, for example, when a resin having a glycidyl group, that is, a so-called epoxy resin, is used as the binder component, examples of the epoxy resin include bisphenol A type epoxy resins, phenol novolak type epoxy resins, O-cresol novolak type epoxy resins, bisphenol F type epoxy resins, biphenyl type epoxy resins, alicyclic epoxy resins, and hydrogenated bisphenol A type epoxy resins. Epoxy resins may be used alone, or two or more types may be used in combination.

[0021] Examples of silane coupling agents include γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-ureidopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, vinyltriethoxysilane, and γ-methacryloxypropyltrimethoxysilane. Among these, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-ureidopropyltriethoxysilane, and γ-glycidoxypropyltrimethoxysilane are preferably used. In addition to silane coupling agents, titanium-based coupling agents, aluminum-based coupling agents, zirconia-based coupling agents, etc., can also be used.

[0022] The surface treatment agent may contain other components as needed, in addition to the binder component and silane coupling agent described above. The surface treatment agent may further contain a crosslinking agent.

[0023] In addition to the above components, the surface treatment agent may further contain other components as needed, such as urethane resin, surfactants and / or defoamers.

[0024] The method for coating the surface of flake glass with a surface treatment agent is not particularly limited, and known methods can be used. For example, by adding a solution of the surface treatment agent to flake glass, stirring, and drying, it is possible to form flake glass in which at least a portion of the surface is coated with the surface treatment agent. The specific methods for adding, stirring, and drying the solution of the surface treatment agent are not particularly limited, but examples are described below.

[0025] For example, in a mixing machine such as a rotary disc mixer or a Henschel mixer equipped with a rotary blade in the mixing container, a predetermined amount of binder is added by spray or the like while the flake glass is flowing, and then mixed and stirred. Next, the flake glass is dried while being stirred in the mixer, or the flake glass is removed from the mixer and dried. By this method, coated flake glass coated with a surface treatment agent can be obtained.

[0026] As another example, flake-shaped glass coated with a surface treatment agent can also be produced using a rolling granulation method as described in Japanese Patent Publication No. 2-124732. That is, flake-shaped glass may be placed in a horizontal vibrating granulator equipped with stirring blades, and a solution of the surface treatment agent may be sprayed onto it for granulation.

[0027] In addition to the methods mentioned above, flake-shaped glass coated with a surface treatment agent can be produced by applying known methods generally known as stirring granulation, fluidized bed granulation, jet granulation, and rotary granulation.

[0028] The drying process is carried out, for example, by heating the flake-shaped glass coated with the surface treatment agent to a temperature above the boiling point of the solvent used in the surface treatment agent solution, and drying it until the solvent evaporates.

[0029] The proportion of surface treatment agent in coated flake glass can be controlled by adjusting the concentration of the surface treatment agent in the surface treatment agent solution that is added or sprayed. That is, by adding or spraying a predetermined amount of surface treatment agent solution to a predetermined amount of flake glass so that the surface treatment agent is present in a predetermined amount, coated flake glass can be produced in which the proportion of the coating film made of surface treatment agent is a predetermined value.

[0030] The composition of the flake-like glass contained in the coated flake-like glass of this embodiment can be any composition of glass that is generally known. Specifically, glass with low alkali metal oxide content, such as E glass, for example, glass in which the total content of Na2O and K2O by mass is 2% or less, can be suitably used.

[0031] The composition of the flake glass contained in the coated flake glass of this embodiment may be within the range of E glass. When used as a filler to reinforce a resin molded product, trace amounts of alkali metal components contained in the E glass may promote the decomposition of the matrix resin.

[0032] The following is a typical composition of E glass. The units of the compositions below are in mass percent. That is, the flake glass contained in the coated flake glass of this embodiment is expressed in mass percent as follows: 52 ≤ SiO2 ≤ 56 12 ≤ Al2O3 ≤ 16 16 ≤ CaO ≤ 25 0 ≤ MgO ≤ 6 0 ≤ (Na2O + K2O) ≤ 2 5 ≤ B2O3 ≤ 13 0 ≤ F2 ≤ 0.5 It may contain the following components: (Na2O+K2O) preferably satisfies 0 ≤ (Na2O+K2O) ≤ 0.8.

[0033] Also, as another type of glass with low alkali metal oxide content, expressed in mass percent, 59 ≤ SiO2 ≤ 65 8 ≤ Al2O3 ≤ 15 47 ≤ (SiO2 - Al2O3) ≤ 57 1 ≤ MgO ≤ 5 20 ≤ CaO ≤ 30 0 < (Li2O + Na2O + K2O) < 2 0 ≤ TiO2 ≤ 5 A glass composition can be used that contains the components of and substantially does not contain B2O3, F, ZnO, BaO, SrO, and ZrO2. This glass composition is disclosed by the applicant in International Publication 2006 / 068255. Glass having this glass composition is called "TA-1 glass". "Substantially does not contain" means that these components are intentionally omitted, except in cases where they are inevitably mixed in by industrial raw materials, for example. Specifically, this means that the content of each of B2O3, F, ZnO, BaO, SrO, and ZrO2 is less than 0.1% by mass (preferably less than 0.05% by mass, more preferably less than 0.03% by mass).

[0034] Furthermore, as another type of glass, expressed in mass%, 60 ≤ SiO2 ≤ 75 5 <Al2O3≦15 3 ≤ CaO ≤ 20 6 ≤ Na₂O ≤ 20 9 ≤ (Li2O + Na2O + K2O) ≤ 20 The following glass composition can also be used. This glass composition is disclosed by the applicant in International Publication 2010 / 024283. Glass having this glass composition is called "TA-2 glass".

[0035] The composition of the flake glass is not limited to the glass compositions of E glass, TA-1 glass, and TA-2 glass described above. For example, the glass compositions of C glass, A glass, ECR glass, and S glass can also be used. The glass compositions of low-dielectric glass disclosed by the applicant (see, for example, Japanese Patent No. 6505950, Japanese Patent No. 6775159, International Publication No. 2020 / 255396, International Publication No. 2020 / 256142, International Publication No. 2020 / 256143, and International Publication No. 2021 / 049581) can also be used.

[0036] Flake-shaped glass can be produced, for example, by the so-called blow method disclosed in Japanese Patent Publication No. 41-17148 and Japanese Patent Publication No. 45-3541, or by the so-called rotary method disclosed in Japanese Patent Publication No. 59-21533 and Japanese Patent Publication No. 2-503669.

[0037] In the blow glass method, the glass manufacturing apparatus shown in Figure 1 can be used. This glass manufacturing apparatus is equipped with a refractory kiln tank 12, a blow nozzle 15, and a pressure roll 17. The glass substrate 11, melted in the refractory kiln tank 12 (melting tank), is inflated into a balloon shape by gas supplied to the blow nozzle 15, forming a hollow glass film 16. The hollow glass film 16 is crushed by the pressure roll 17 to obtain flake glass 1. The thickness of the flake glass 1 can be controlled by adjusting the tensile speed of the hollow glass film 16, the flow rate of gas supplied from the blow nozzle 15, etc.

[0038] In the rotary method, the glass manufacturing apparatus shown in Figure 2 can be used. This glass manufacturing apparatus comprises a pipe 21, a rotating cup 22, a set of annular plates 23, and an annular cyclone-type collector 24. The molten glass substrate 11 is poured from the pipe 21 into the rotating cup 22, flows out radially from the upper edge of the rotating cup 22 by centrifugal force, is sucked in by an airflow through the annular plates 23, and introduced into the annular cyclone-type collector 24. As it passes through the annular plates 23, the glass cools and solidifies in the form of a thin film, and is further crushed into minute pieces to obtain flake-like glass 1. The thickness of the flake-like glass 1 can be controlled by adjusting the spacing of the annular plates 23, the speed of the airflow, etc.

[0039] The coated flake-shaped glass of this embodiment, when used as a filler to reinforce a resin molded product as described above, can suppress the decomposition of the matrix resin while maintaining its function as a filler. In other words, the coated flake-shaped glass of this embodiment may be used as a filler to reinforce a resin molded product. The resin molded product may contain polycarbonate as the matrix resin. Polycarbonate is known to be susceptible to alkaline components. When the carbonate bonds contained in polycarbonate come into contact with alkaline components, the decomposition of the resin progresses. The coated flake-shaped glass of this embodiment, when used as a filler to reinforce a resin molded product containing polycarbonate as the matrix resin, can particularly suppress the decomposition of the matrix resin in the resin molded product.

[0040] [Resin composition] Next, the resin composition of this embodiment will be described. The resin composition of this embodiment includes a matrix resin and the coated flake-shaped glass of this embodiment described above. By including the coated flake-shaped glass of this embodiment having the above characteristics as a filler, the resin composition of this embodiment can suppress the decomposition of the matrix resin in the resin molded product. As a result, the deterioration of the mechanical properties and appearance of the resin molded product is suppressed.

[0041] The average particle size of the flake glass contained in the resin composition of this embodiment satisfies the same numerical range as the average particle size of the flake glass of this embodiment described above. However, the average particle size of the flake glass may be affected by the influence of dispersion in the resin composition, specifically by extrusion molding to obtain the resin composition containing coated flake glass and / or injection molding to mold the resin composition and obtain a resin molded product. Therefore, the average particle size of the flake glass in the resin composition is not necessarily the same as the average particle size of the flake glass contained in the coated flake glass before dispersion in the resin composition.

[0042] The average particle size of the flake-like glass contained in the resin composition of this embodiment was measured by heating the resin composition in an atmosphere of 625°C, removing components other than the flake-like glass, and then dispersing the extracted flake-like glass in water.

[0043] The matrix resin may be, for example, a thermoplastic resin. The thermoplastic resin may be at least one selected from the group consisting of polypropylene, polyethylene, polybutylene terephthalate, polyethylene terephthalate, polycarbonate, polystyrene-based resins, styrene-acrylonitrile copolymer resins, polyacrylate, styrene-butadiene-acrylonitrile copolymer resins, polyarylene sulfide, polyphenylene sulfide, polyacetal, polyamide, polyamide-imide, liquid crystal polymer, polyetheretherketone, and polyetherimide.

[0044] The thermoplastic resin may be polycarbonate. Polycarbonate is known to be susceptible to alkaline components. When the carbonate bonds contained in polycarbonate come into contact with alkaline components, the resin decomposes. With the coated flake-like glass of this embodiment described above, even when polycarbonate is used as the matrix resin, the decomposition of the matrix resin in the molded resin product can be suppressed.

[0045] The content of flake glass in the resin composition is preferably 3 to 70% by mass. A content of 3% by mass or more allows the flake glass to fully exhibit its function as a reinforcing material. On the other hand, a content of 70% by mass or less allows the flake glass to be uniformly dispersed in the resin composition. To further reduce the molding shrinkage rate, a flake glass content of 10% by mass or more and 50% by mass or less is more preferable.

[0046] The resin composition may contain other components besides the matrix resin and coated flake glass. These other components may include, for example, fillers such as carbon black. 、 Examples include thermoplastic elastomers, stabilizers, antioxidants, and flame retardants. Examples of stabilizers include phosphorus-based and lactone-based stabilizers. Examples of antioxidants include hindered phenol compounds and phosphite compounds. Examples of flame retardants include bromine-based, phosphorus-based, and silicone-based flame retardants. Two or more of these can be used in combination.

[0047] In resin molded products made using the resin composition of this embodiment, the deterioration of mechanical properties and appearance is suppressed due to the effect of suppressing the decomposition of the matrix resin by the coating flake-like glass. [Examples]

[0048] The present invention will be described in more detail below with reference to examples. However, the present invention is not limited to the following examples.

[0049] [Coated flake glass] The molding, crushing / classification, and surface treatment processes used to produce the coated flake-shaped glass were carried out by the methods described below.

[0050] <Molding> Using E glass having the composition shown in Table 1, flake-shaped glass was produced by the blowing method described with reference to Figure 1. Specifically, E glass was placed in a melting bath heated to over 1200°C and melted. Thin glass was produced by blowing air through a nozzle, and this thin glass was continuously drawn out with rollers. By adjusting the amount of air blown in and the roller rotation speed, flake-shaped glass with an average thickness of 0.7 μm was obtained.

[0051] [Table 1]

[0052] The average thickness of the flake-shaped glass was calculated by measuring the thickness of 100 glass substrates using a scanning electron microscope (SEM), dividing the total thickness by the number of substrates measured, and rounding the result to two decimal places.

[0053] <Crushing and Classification> After crushing the flake-shaped glass using a ball mill, classification was performed to obtain flake-shaped glass with an average particle size of 160 μm.

[0054] Furthermore, since the flake-shaped glass does not break in the thickness direction, i.e., the perpendicular direction, there was no difference in the average thickness of the glass before and after crushing.

[0055] Ball mills that can be used include rolling ball mills (pot mills, tube mills, conical mills, etc.), vibratory ball mills (circular vibration type vibratory mills, orbital vibration type vibratory mills, centrifugal mills, etc.), and planetary mills.

[0056] In this embodiment, grinding was performed using a ball mill, but the grinding method is not limited to this, and grinding may be performed by other grinding methods, whether wet or dry. For example, an impact crusher, gyratory crusher, cone crusher, jaw crusher, roll crusher, cutter mill, self-grinding mill, stamp mill, stone mill, smelting mill, ring mill, roller mill, jet mill, hammer mill, pin mill, rotary mill, vibratory mill, planetary mill, attritor, or bead mill can be used individually. These methods may be used in combination as appropriate.

[0057] The classification was performed by sieving. Sieving may be performed in multiple stages, rather than just once.

[0058] For sieving and classification, for example, a dry vibrating sieve can be used. For instance, by using a sieve with a mesh size of a predetermined size or larger to remove particularly large particles, and then using a sieve with a mesh size of a predetermined size or smaller to further remove the next largest particles, flake-shaped glass with the target D50 can be obtained. The mesh size of the sieve used here should be appropriately selected according to the particle size of the particles before sieving and the desired D50 of the flake-shaped glass.

[0059] In this embodiment, classification was performed using a sieve, but the classification method is not limited to this. The target D50 can be achieved by other classification methods, whether wet or dry. For example, in gravity field classification, horizontal flow and vertical upward flow (wet, air-tube type, fluidized bed type, multi-stage bend type) can be used. In inertial force field classification, linear type, curved type (impactor type), and inclined type (louver type, Coanda effect type) can be used. In centrifugal force field classification, natural vortex type and forced vortex type can be used.

[0060] The average particle size (D50) of the flake-shaped glass was measured by dispersing the flake-shaped glass in water using a laser diffraction particle size distribution analyzer (Microtrac-Bell Co., Ltd., model: MT3300EX, measurement mode: HRA).

[0061] <Surface treatment> For surface treatment, either surface treatment A or B was adopted.

[0062] (Surface treatment A) 5 kg of flake glass was placed in a Henschel mixer and mixed and stirred for 15 minutes while adding the surface treatment solution by spray. The surface treatment solution was prepared using water as the solvent, with an emulsion of bisphenol A type epoxy resin as the binder component and hydrolyzed solutions of γ-glycidoxypropyltrimethoxysilane and γ-aminopropyltriethoxysilane as silane coupling agents. The silane coupling agents were added so that the mass ratio of γ-glycidoxypropyltrimethoxysilane and γ-aminopropyltriethoxysilane after drying was 1:1. After that, the undried flake glass was removed from the mixer and dried in a dryer at 125°C for 8 hours to obtain coated flake glass in which at least a portion of the surface was covered with the surface treatment agent.

[0063] (Surface treatment B) Except for using a phenol novolac-type epoxy resin emulsion as the binder component and using only γ-aminopropyltriethoxysilane as the silane coupling agent, coated flake-like glass with at least a portion of its surface covered with the surface treatment agent was obtained by the same method as surface treatment A.

[0064] <Calculation of silane coupling agent content> The calculated silane coupling agent content was determined for coated flake-shaped glass after surface treatment A or B was applied and then dried.

[0065] <Calculation of binder content> The calculated binder content was determined for coated flake-shaped glass that had undergone surface treatment A or B and then dried.

[0066] <Calculation of surface treatment agent adhesion rate> The adhesion rate of the surface treatment agent was evaluated by the ignition loss method. In this embodiment, the adhesion rate of the surface treatment agent is the proportion of the coating film consisting of the surface treatment agent in the coated flake glass. Specifically, an appropriate amount of coated flake glass was dried at 110°C, then heated in an atmosphere of 625°C to remove the surface treatment agent from the surface of the coated flake glass, and the adhesion rate of the surface treatment agent in the coated flake glass was calculated from the difference between the mass of the coated flake glass before heating and the mass of the flake glass after heating.

[0067] [Examples 1-2, Comparative Examples 1-3] The measured values ​​and calculated values ​​for the coated flake-like glass in Examples 1-2 and Comparative Examples 1-3 are shown in Table 2.

[0068] [Reference examples 1~3] Table 3 shows the measured and calculated values ​​for each of the coated flake-like glass samples in Reference Examples 1-3.

[0069] [Table 2]

[0070] [Table 3]

[0071] [Resin molded product] [Examples 1-2, Comparative Examples 1-3] The resin molded articles of Examples 1-2 and Comparative Examples 1-3 were molded using the following method. Polycarbonate (Yupilon S3000F, manufactured by Mitsubishi Engineering Plastics Corporation) was used as the matrix resin. Coated flake glass and polycarbonate were uniformly mixed in the desired proportions. For example, in Example 1, they were uniformly mixed to be 40% by mass and 60% by mass, respectively. The resulting mixture was kneaded in an extrusion molding machine (Technovel Corporation, KZW15-30MG, molding temperature: 265-270°C) under molding conditions for polycarbonate to obtain a resin composition containing polycarbonate as the matrix resin and coated flake glass as a reinforcing filler. No stabilizers or antioxidants were added. This resin composition was molded in an injection molding machine (Nissei Plastic Industrial Co., Ltd., HM7) to obtain resin molded articles.

[0072] [Reference examples 1~3] Except for using polyamide 66 (Amiran 3001N, manufactured by Toray Industries, Inc.), which is less susceptible to decomposition by alkaline components than polycarbonate, as the matrix resin, and modifying the molding conditions for polyamide 66, the resin molded products of Reference Examples 1 to 3 were obtained by the same method as in Examples 1 to 2 and Comparative Examples 1 to 3.

[0073] <Calculation of the content of flake-like glass in resin compositions> The flake glass content in the resin composition was evaluated by the ignition loss method. Specifically, an appropriate amount of the molded resin product was heated in an atmosphere of 625°C to remove components other than the flake glass, and the flake glass content in the resin composition was calculated from the difference between the mass of the molded resin product before heating and the mass of the residue (flake glass) after heating.

[0074] <Measurement of particle size distribution using laser diffraction and scattering methods> The particle size distribution was measured using laser diffraction and scattering methods on the flake glass residue generated during the calculation of the flake glass content in the resin composition. Specifically, a laser diffraction particle size distribution analyzer (Microtrac-Bell Co., Ltd., model: MT3300EX, measurement mode: HRA) was used to disperse each flake glass in water and measure its particle size distribution. From the measurement results, the D50 value of the flake glass in the resin composition was read. In the particle size distribution, D50 was defined as the particle size at which the volume accumulation from the smallest particle size side corresponds to 50%. The results are shown in Tables 2 and 3.

[0075] <Evaluation of the degree of degradation of matrix resin> The degree of decomposition of the matrix resin in resin molded products was evaluated by measuring the melt flow rate (MFR) of the resin composition. MFR is known as a parameter that represents a measure of the molecular weight of the resin. Generally, molten resin is held in a cylinder, an appropriate load is applied to the resin, and the amount of resin that flows out of the orifice in 10 minutes is expressed as MFR. MFR is an indicator of the viscosity of the molten resin, but it is also related to the molecular weight. That is, as the molecular weight of the resin increases, the MFR decreases, and as the molecular weight decreases, the MFR increases. As the molecular weight of the resin increases, the strength of the resin molded product tends to increase. Here, MFR was measured in accordance with JIS K 7210 under conditions of a temperature of 270°C and a load of 2.16 kg. The results are shown in Tables 2 and 3.

[0076] <Measurement of characteristic values ​​of resin molded products> The maximum tensile strength of the resin molded product was measured according to JIS K 7113. The results are shown in Tables 2 and 3.

[0077] As shown in Table 3, in Reference Examples 1-3, where polyamide 66, which is less decomposed by alkaline components than polycarbonate, was used as the matrix resin, a general trend was observed where the MFR decreased as the content of coated flake-like glass in the resin composition increased. In contrast, as shown in Comparative Examples 1-2 in Table 2, when polycarbonate, which is easily decomposed by alkaline components, was used as the matrix resin, the MFR tended to increase as the content of coated flake-like glass in the resin composition increased. Although omitted in Table 2, resin compositions with a lower content of flake-like glass in the resin composition than Comparative Example 1 (e.g., 20% by mass) showed a lower MFR than Comparative Example 1.

[0078] As shown in Table 2, Examples 1-2 and Comparative Examples 2-3 all had a high content of coated flake-like glass in the resin composition (40% by mass), creating conditions conducive to resin decomposition. Nevertheless, Examples 1-2 showed a lower MFR compared to Comparative Example 2. This is presumed to be because, in Examples 1-2, the adhesion rate of the surface treatment agent to the coated flake-like glass was 5% by mass or more, which suppressed the decomposition of the polycarbonate matrix resin. In fact, Examples 1-2 showed superior maximum tensile strength of the resin molded product compared to Comparative Example 2. In contrast, in Comparative Example 2, it is presumed that when the polycarbonate and coated flake-like glass were kneaded at high temperature during extrusion molding, the decomposition of the polycarbonate progressed due to trace amounts of alkali metal contained in the flake-like glass, which is the E-glass. Furthermore, in Comparative Example 3, the resin did not sag, making MFR measurement impossible. This is presumed to be because, in Comparative Example 3, when the resin was held at a high temperature at which the polycarbonate melted, the excess binder component present on the coated flake-like glass melted, flowed out near the adhesive interface with the polycarbonate, and excessively reacted with the polycarbonate, causing a viscosity increase that was impossible to measure under MFR measurement conditions. Furthermore, in Comparative Example 3, the adhesion rate of the surface treatment agent on the coated flake-like glass was too high at 13.0 mass%, resulting in excessively strong bonding between the coated flake-like glass particles, which reduced the dispersibility of the coated flake-like glass during extrusion molding. In addition, the excessive amount of surface treatment agent adhesion hindered adhesion, leading to a decrease in mechanical properties. In contrast, in Examples 1 and 2, the adhesion rate of the surface treatment agent on the coated flake-like glass was less than 10 mass%, which is presumed to have suppressed the decrease in dispersibility of the coated flake-like glass and maintained mechanical properties. In fact, Examples 1 and 2 showed superior maximum tensile strength of the resin molded products compared to Comparative Example 3.

[0079] Although not shown in Table 2, in Examples 1 and 2, the maximum bending strength and flexural modulus of the resin molded products measured according to JIS K7171 were good values. The maximum bending strength of the resin molded product in Example 1 was 164 MPa, and the maximum bending strength of the resin molded product in Example 2 was 154 MPa. The flexural modulus of the resin molded product in Example 1 was 7910 MPa, and the flexural modulus of the resin molded product in Example 2 was 7860 MPa. [Industrial applicability]

[0080] The flake-shaped glass of the present invention, when used as a filler to reinforce resin molded products, can suppress the decomposition of the matrix resin while maintaining its function as a filler, thereby improving the mechanical properties and appearance of the resin molded products, and is therefore applicable to a wide range of uses. For example, a resin composition containing the coated flake-shaped glass of the present invention and a thermoplastic resin is suitably used in fields such as automobiles and electrical / electronic components. More specifically, by using polycarbonate or the like as the thermoplastic resin, it can be applied to engineering components. [Explanation of symbols]

[0081] 1. Flake-shaped glass 11. Molten glass substrate 12 Fireproof kiln tank 15 Blow nozzle 16 Hollow glass film 17 Pressure Roll 21 pipes 22 Rotating Cups 23 A set of ring plates 24. Annular cyclone type collection device

Claims

1. Flake-shaped glass and, A coating film consisting of a surface treatment agent that covers at least a portion of the surface of the flake-shaped glass, A coated flake-like glass containing, The content ratio of the surface treatment agent in the coated flake-like glass is 5.4% by mass or more and less than 10% by mass. The aforementioned flake-like glass has an average thickness of 0.1 to 1.0 μm and an average particle size of 0.1 to 2000 μm. The aforementioned flake-like glass is expressed in mass%, 52≦SiO 2 ≦56 12≦Al 2 O 3 ≦16 16 ≤ CaO ≤ 25 0 ≤ MgO ≤ 6, 0≦(Na 2 O+K 2 O)≦2 5≦B 2 O 3 ≦13 0≦F 2 ≦0.5 Contains the following ingredients: Coated flake-like glass.

2. It is used as a filler to reinforce resin molded products containing polycarbonate as the matrix resin. The coated flake-like glass according to claim 1.

3. Matrix resin and A coated flake-like glass according to claim 1 or 2, including, Resin composition.

4. The matrix resin is a thermoplastic resin. The resin composition according to claim 3.

5. The thermoplastic resin is polycarbonate. The resin composition according to claim 4.

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