JP2023158687A - Coated flaky glass and resin composition - Google Patents

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

The present invention relates to coated glass flakes and resin compositions.

In resin molded products, glass fiber, carbon fiber, etc., glass beads, and flaky base materials such as glass flakes, mica, and talc are used to reduce warpage and deformation and/or improve mechanical strength. It is generally known that it is blended into matrix resin as a filler.

For example, in Patent Document 1, the glass flakes contain a thermoplastic resin, glass flakes with an average thickness of 0.2 to 0.7 μm, and a surface treatment deactivator, and the amount of the surface treatment agent on the glass flakes is 100 μm. Glass-reinforced resin compositions have been proposed that are 1.5 to 5 parts by weight. Further, Patent Document 2 discloses a granular flake glass containing flake glass having an average thickness of 0.1 to 2.0 μm and an average particle size of 10 to 2000 μm, and a binder for granulating the glass flake. Granule flakes, wherein the solid content mass ratio of the binder in the glass granules is in the range of 1.0% by mass to 5.0% by mass, and the binder contains a coupling agent in the range of 9% by mass or less. Glasses and resin compositions using them have been proposed.

Japanese Patent Application Publication No. 2012-207075 International Publication No. 2013/121756

Some resins, especially thermoplastic resins, are easily decomposed by alkaline components. When such a resin is used as a matrix resin for a resin molded article, the resin may be decomposed due to the alkaline component contained in the glass flakes, resulting in deterioration of the mechanical properties and appearance of the resin molded article. In order to suppress the decomposition of matrix resins, methods of adding stabilizers or antioxidants have been proposed. Examples of the stabilizer include phosphorus-based stabilizers, lactone-based stabilizers, and the like. Examples of the antioxidant include antioxidants such as hindered phenol compounds and phosphite compounds. However, if the amount of stabilizer or antioxidant added is too large, the mechanical properties of the resin molded article will deteriorate. Also, so-called bloom or bleed may occur, in which the stabilizer or antioxidant migrates to the surface of the matrix resin.

One of the objects of the present invention is to provide a coated glass flake suitable for suppressing decomposition of a matrix resin while maintaining the function as a filler when used as a filler for reinforcing a resin molded product. Another object of the present invention is to suppress decomposition of matrix resin in resin molded articles.

From one aspect of the present invention,
flaky glass,
a surface treatment agent that covers at least a portion of the surface of the glass flake;
A coated flake glass comprising:
The content ratio of the surface treatment agent in the coated flaky glass is 5% by mass or more and less than 10% by mass,
A coated flake glass is provided.

From another aspect of the present invention,
matrix resin;
The coated flake glass of the present invention,
including,
A resin composition is provided.

According to the present invention, there is provided a coated glass flake suitable for suppressing the decomposition of matrix resin while maintaining the function as a filler when used as a filler for reinforcing a resin molded product, and further, Decomposition of the matrix resin in the molded product can be suppressed.

FIG. 1 is a schematic diagram illustrating an example of an apparatus for producing glass flakes. It is a schematic diagram explaining another example of a manufacturing apparatus of flaky glass.

Hereinafter, embodiments of the coated flaky glass and resin composition of the present invention will be described in detail, but the following description is not intended to limit the present invention to specific embodiments.

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

The coated glass flakes of this embodiment contain a surface treatment agent that covers at least a portion of the surface of the glass flakes as described above. The content of the surface treatment agent in the coated flaky glass is 5% by mass or more and less than 10% by mass. When the content of the surface treatment agent is 5% by mass or more, a sufficient effect of suppressing the decomposition of the matrix resin can be obtained. When the content of the surface treatment agent is less than 10% by mass, it is possible to avoid deterioration in the dispersibility of the glass flakes due to an excessive amount of the surface treatment agent. Therefore, since the coated flake glass of this embodiment has a surface treatment agent content in the above range, when it is used as a filler to reinforce a resin molded product, it maintains its function as a filler while maintaining its function as a filler. Decomposition of matrix resin can be suppressed. Therefore, it is also possible to suppress the amount of stabilizer or antioxidant added. Thus, according to the coated flaky glass of the present embodiment, it is possible to suppress deterioration in mechanical properties and deterioration in appearance of the resulting resin molded product.

The content of the surface treatment agent in the coated flaky glass of this embodiment may be 5% by mass or more and 8% by mass or less.

The glass flakes included in the coated glass flakes 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.

As described above, the average thickness of the glass flakes included in the coated glass flakes of this embodiment may be within the range of 0.1 to 1.0 μm. The average thickness may be within the range of 0.5-1.0 μm. In this specification, the average thickness of glass flakes is defined as, for example, the thickness of 100 or more pieces of glass flakes is measured using a scanning electron microscope (SEM), and the total thickness is calculated by the number of sheets measured. It can be calculated as the divided value.

The average particle size of the glass flakes included in the coated glass flakes of this embodiment may be within the range of 0.1 to 2000 μm as described above. The average particle size may be 1.0 μm or more, 10 μm or more, or even 100 μm or more, for example, within the range of 100 to 300 μm. The average particle size may be 200 μm or less. In addition, in this specification, the average particle size of flaky glass corresponds to the volume accumulation from the small particle size side of 50% in the particle size distribution of flaky glass measured based on the laser diffraction/scattering method. The particle size (D50) is

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

The binder component contained in the surface treatment agent is not particularly limited, and any known binder component used for surface treatment of glass flakes can be used as appropriate. For example, organic binder components include methylcellulose, carboxymethylcellulose, starch, carboxymethylstarch, hydroxyethylcellulose, hydroxypropylcellulose, polyvinyl alcohol, acrylic resin, epoxy resin, epoxy-modified polyolefin resin, phenolic resin, vinyl acetate, and urethane resin. etc. Examples of the inorganic binder component include water glass, colloidal silica, and colloidal alumina.

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

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

In addition to the binder component and silane coupling agent described above, the surface treatment agent may contain other components as necessary. The surface treatment agent may further contain a crosslinking agent.

In addition to the above-mentioned components, the surface treatment agent may further contain other components such as a urethane resin, a surfactant, and/or an antifoaming agent, if necessary.

The method of coating the surface of the glass flakes with the surface treatment agent is not particularly limited, and any known method can be used. For example, by adding a solution of the surface treatment agent to glass flakes, stirring and drying, it is possible to form glass flakes in which at least a portion of the surface is coated with the surface treatment agent. Specific methods for adding, stirring and drying the solution of the surface treatment agent are not particularly limited, but examples thereof will be explained below.

For example, in a mixer such as a rotating disk mixer or a Henschel mixer equipped with a rotary blade in a mixing container, a predetermined amount of the binder is added by spraying or the like while the glass flakes are flowing, and mixed and stirred. Next, the glass flakes are dried while stirring in a mixer, or the glass flakes are taken out from the mixer and dried. By this method, coated glass flakes coated with a surface treatment agent can be obtained.

Further, as another example, glass flakes coated with a surface treatment agent can also be produced using a rolling granulation method as described in JP-A-2-124732. That is, glass flakes may be placed in a horizontal vibration type granulator equipped with stirring blades, and a solution of the surface treatment agent may be sprayed onto the glass flakes to form granules.

In addition to the above, glass flakes coated with a surface treatment agent can be produced by applying known methods generally called agitation granulation, fluidized bed granulation, jet granulation, and rotary granulation. can.

The drying step is performed, for example, by heating the glass flakes coated with the surface treatment agent to a temperature equal to or higher than the boiling point of the solvent used in the surface treatment agent solution and drying the glass flakes until the solvent evaporates.

The content ratio of the surface treatment agent in the coated glass flakes can be controlled by adjusting the concentration of the surface treatment agent in the surface treatment agent solution to be added or sprayed. That is, by adding or spraying a predetermined amount of surface treatment agent solution to a predetermined amount of glass flakes so that the surface treatment agent becomes a predetermined amount, the content ratio of the coating film made of the surface treatment agent is adjusted to a predetermined value. It is possible to produce coated glass flakes with a high value.

As the composition of the glass flakes included in the coated glass flakes of this embodiment, commonly known glass compositions can be used. Specifically, a glass containing a small amount of alkali metal oxide such as E-glass, for example a glass in which the total content of Na ₂ O and K ₂ O is 2% or less on a mass basis, can be suitably used.

The composition of the glass flakes included in the coated glass flakes of this embodiment may be in the range of E glass. When used as a filler for reinforcing resin molded products, trace amounts of alkali metal components contained in E-glass can promote decomposition of the matrix resin.

A typical composition of E-glass is shown below. The units of the following compositions are mass %. That is, the flaky glass contained in the coated flaky glass of this embodiment is expressed in mass %,
52≦ _SiO2 ≦56
12≦Al ₂ O ₃ ≦16
16≦CaO≦25
0≦MgO≦6
0≦( _Na2O + _K2O )≦2
5≦B ₂ O ₃ ≦13
0≦ _F2 ≦0.5
It may contain the following ingredients. (Na ₂ O+K ₂ O) preferably satisfies 0≦(Na ₂ O+K ₂ O)≦0.8.

In addition, as another glass with less alkali metal oxide, expressed in mass%,
59≦ _SiO2 ≦65
8≦Al ₂ O ₃ ≦15
47≦(SiO ₂ -Al ₂ O ₃ )≦57
1≦MgO≦5
20≦CaO≦30
0<( _Li2O + _Na2O + _K2O )<2
0≦ _TiO2 ≦5
A glass composition containing the following components and substantially free of B ₂ O ₃ , F, ZnO, BaO, SrO, and ZrO ₂ can be used. The glass composition is disclosed by the applicant in WO 2006/068255. Glass having this glass composition is called "TA-1 glass." Note that "substantially not containing" means that it is not intentionally included, unless it is unavoidably mixed, for example, by industrial raw materials. Specifically, the content of each of B ₂ O ₃ , F, ZnO, BaO, SrO and ZrO ₂ is less than 0.1% by mass (preferably less than 0.05% by mass, more preferably 0.03% by mass). less than).

Furthermore, as another glass, expressed in mass %,
60≦SiO ₂ ≦75
5<Al ₂ O ₃ ≦15
3≦CaO≦20
6≦Na ₂ O≦20
9≦( _Li2O + _Na2O + _K2O )≦20
Other glass compositions can also be used. The glass composition is disclosed by the applicant in WO 2010/024283. Glass having this glass composition is called "TA-2 glass."

The composition of the glass flakes is not limited to the glass compositions of E glass, TA-1 glass, and TA-2 glass shown above. For example, glass compositions of C glass, A glass, ECR glass, and S glass can also be used. Low dielectric glasses disclosed by the present applicant (for example, Patent No. 6505950, Patent No. 6775159, International Publication No. 2020/255396, International Publication No. 2020/256142, International Publication No. 2020/256143, International Publication 2021/049581) can also be used.

Flake glass can be produced, for example, by the so-called blow method disclosed in Japanese Patent Publications No. 41-17148 and Japanese Patent Publication No. 45-3541, and Japanese Patent Application Laid-open No. 59-21533 and Japanese Patent Application Publication No. 2-503669. It can be produced by the so-called rotary method disclosed in .

In the blowing method, a glass manufacturing apparatus shown in FIG. 1 can be used. This glass manufacturing apparatus includes a fireproof kiln tank 12, a blow nozzle 15, and a pressure roll 17. The glass base 11 melted in the refractory kiln tank 12 (melting tank) is blown up into a balloon shape by the gas sent into the blow nozzle 15, and becomes a hollow glass film 16. The hollow glass membrane 16 is crushed by a press roll 17 to obtain glass flakes 1. The thickness of the glass flakes 1 can be controlled by adjusting the pulling speed of the hollow glass membrane 16, the flow rate of the gas sent from the blow nozzle 15, and the like.

In the rotary method, a glass manufacturing apparatus shown in FIG. 2 can be used. This glass manufacturing apparatus includes a pipe 21, a rotary cup 22, a set of annular plates 23, and an annular cyclone collector 24. The molten glass base 11 is poured into the rotating cup 22 from the pipe 21, flows out radially from the upper edge of the rotating cup 22 due to centrifugal force, passes between the annular plates 23, is sucked by the air flow, and is passed through the annular cyclone type trap. It is introduced into the collector 24. While passing through the annular plate 23, the glass cools and solidifies in the form of a thin film, and is further crushed into minute pieces, thereby obtaining the glass flakes 1. The thickness of the glass flakes 1 can be controlled by adjusting the spacing between the annular plates 23, the speed of the air flow, and the like.

When the coated flaky glass of this embodiment is used as a filler for reinforcing a resin molded product as described above, it can suppress the decomposition of the matrix resin while maintaining its function as a filler. That is, the coated flaky glass of this embodiment may be used as a filler for reinforcing a resin molded product. The resin molded article may contain polycarbonate as a matrix resin. Polycarbonate is known to be sensitive to alkaline components. When carbonate bonds contained in polycarbonate come into contact with an alkali component, decomposition of the resin progresses. The coated flaky glass of the present embodiment described above can particularly suppress decomposition of the matrix resin in the resin molded product when used as a filler for reinforcing a resin molded product containing polycarbonate as the matrix resin.

[Resin composition]
Next, the resin composition of this embodiment will be explained. The resin composition of this embodiment includes a matrix resin and the coated flaky glass of this embodiment described above. The resin composition of the present embodiment can suppress decomposition of the matrix resin in the resin molded product by containing the coated flaky glass of the present embodiment having the above characteristics as a filler. As a result, deterioration in mechanical properties and appearance of the resin molded product is suppressed.

The value of the average particle diameter of the glass flakes contained in the resin composition of this embodiment satisfies the same numerical range as the average particle diameter of the glass flakes of this embodiment described above. However, the average particle size of the glass flakes is affected by the dispersion into the resin composition, specifically by extrusion molding to obtain a resin composition containing coated glass flakes and/or by molding the resin composition into a resin. May be affected by injection molding to obtain molded parts. Therefore, the average particle size of the glass flakes in the resin composition is not necessarily the same as the average particle size of the glass flakes contained in the coated glass flakes before being dispersed in the resin composition.

The average particle diameter of the glass flakes contained in the resin composition of this embodiment is determined by heating the resin composition in an atmosphere of 625°C and removing components other than glass flakes. This is a value measured by dispersing it in water.

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

The thermoplastic resin may be polycarbonate. Polycarbonate is known to be sensitive to alkaline components. When carbonate bonds contained in polycarbonate come into contact with an alkali component, decomposition of the resin progresses. According to the coated flaky glass of the present embodiment described above, even when polycarbonate is used as the matrix resin, decomposition of the matrix resin in the resin molded product can be suppressed.

The content of flaky glass in the resin composition is preferably 3 to 70% by mass. By setting it as 3 mass % or more, the function as a reinforcing material of glass flakes can be fully exhibited. On the other hand, by setting the content to 70% by mass or less, glass flakes can be uniformly dispersed in the resin composition. In order to suppress the molding shrinkage rate to a lower level, it is more preferable that the content of the glass flakes is 10% by mass or more and 50% by mass or less.

The resin composition may contain components other than the matrix resin and the coated glass flakes. Examples of other components include fillers such as carbon black , thermoplastic elastomers, stabilizers, antioxidants, flame retardants, and the like. Examples of the stabilizer include phosphorus-based stabilizers, lactone-based stabilizers, and the like. Examples of the antioxidant include antioxidants such as hindered phenol compounds and phosphite compounds. Examples of the flame retardant include bromine-based, phosphorus-based, and silicone-based flame retardants. Two or more of these can also be used in combination.

In the resin molded article produced using the resin composition of the present embodiment, deterioration in mechanical properties and deterioration in appearance are suppressed due to the suppressing effect of the covering flake glass on decomposition of the matrix resin.

Hereinafter, the present invention will be explained in more detail using Examples. However, the present invention is not limited to the following examples.

[Coated flake glass]
Molding, crushing/classification, surface treatment, etc. in producing the coated glass flakes were performed by the methods shown below.

<Molding>
Using E glass having the composition shown in Table 1, glass flakes were produced by the blowing method described with reference to FIG. Specifically, E glass was placed in a melting tank heated to 1200° C. or higher and melted. Thin glass was prepared by blowing air through a nozzle, and this thin glass was continuously pulled out with a roller. The amount of air blown and the number of rotations of the rollers were adjusted to obtain glass flakes with an average thickness of 0.7 μm.

The average thickness of the glass flakes was calculated by measuring the thickness of 100 glass substrates using a SEM, dividing the total thickness by the number of sheets measured, and rounding off the value to the second decimal place.

<Crushing/Classification>
After the glass flakes were crushed using a ball mill, they were classified to obtain glass flakes with an average particle size of 160 μm.

Note that since glass flakes do not break in the thickness direction, that is, in the vertical direction, there was no difference in the average thickness of the glass before and after crushing.

As the ball mill, a rolling ball mill (pot mill, tube mill, conical mill, etc.), a vibrating ball mill (circular vibrating vibrating mill, orbiting vibrating mill, centrifugal mill, etc.), a planetary mill, etc. can be used.

In this example, pulverization was performed using a ball mill, but the pulverization method is not limited to this, and pulverization may be performed by other pulverization methods, whether wet or dry. For example, impact crusher, gyratory crusher, cone crusher, jaw crusher, roll crusher, cutter mill, autogenous crusher, stamp mill, stone mill, mill, ring mill, roller mill, jet mill, hammer mill, pin mill, rotary mill. A mill, vibratory mill, planetary mill, attritor, or bead mill can be used alone. These methods may be used in combination as appropriate.

Classification was performed by sieving and classification. The sieving and classification may be performed not only once but also in multiple times.

For sieving and classification, for example, a dry vibrating sieve can be used. For example, a sieve with apertures larger than a predetermined size is used to remove particularly large particles, and then a sieve with apertures smaller than a predetermined size is used to remove the next largest particles. By removing it, flaky glass having the target D50 can be obtained. Note that the opening size of the sieve used here may be appropriately selected depending on the particle size of the particles before sieving and the D50 of the glass flakes to be obtained.

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

The average particle diameter (D50) of the glass flakes is measured by dispersing the glass flakes in water using a laser diffraction particle size distribution measuring device (manufactured by Microtrac Bell Co., Ltd., model: MT3300EX, measurement mode: HRA). did.

<Surface treatment>
As the surface treatment, the following surface treatment A or B was adopted.

(Surface treatment A)
5 kg of glass flakes were placed in a Henschel mixer, and mixed and stirred for 15 minutes while spraying a surface treatment agent solution thereon. The surface treatment agent solution uses water as a solvent and contains an emulsion of bisphenol A type epoxy resin as a binder component and γ-glycidoxypropyltrimethoxysilane and γ-aminopropyltriethoxysilane as silane coupling agents. It was prepared by adding a hydrolyzate. The silane coupling agent was added so that the mass ratio of γ-glycidoxypropyltrimethoxysilane and γ-aminopropyltriethoxysilane after drying was 1:1. Thereafter, the undried glass flakes were taken out of the mixer and dried in a dryer at 125° C. for 8 hours to obtain coated glass flakes in which at least a portion of the surface was covered with a surface treatment agent.

(Surface treatment B)
At least a portion of the surface was treated with the surface treatment agent using the same method as surface treatment A, except that an emulsion of a phenol novolac type epoxy resin was used as the binder component and only γ-aminopropyltriethoxysilane was used as the silane coupling agent. A coated glass flake was obtained.

<Calculation of silane coupling agent content>
The calculated content of the silane coupling agent was calculated for the coated glass flakes that had been subjected to surface treatment A or B and dried.

<Calculation of binder content>
The calculated binder content was calculated for the coated glass flakes that had been subjected to surface treatment A or B and dried.

<Calculation of adhesion rate of surface treatment agent>
The adhesion rate of the surface treatment agent was evaluated by the ignition loss method. In the present embodiment, the adhesion rate of the surface treatment agent is the content ratio of the coating film made of the surface treatment agent in the coated flake glass. Specifically, after drying an appropriate amount of coated glass flakes at 110°C, the surface treatment agent is removed from the surface of the coated glass flakes by heating in an atmosphere of 625°C. The adhesion rate of the surface treatment agent on the coated glass flakes was calculated from the difference between the mass and the mass of the glass flakes after heating.

[Examples 1-2, Comparative Examples 1-3]
Table 2 shows the measured values and calculated values for the coated glass flakes of Examples 1 to 2 and Comparative Examples 1 to 3.

[Reference examples 1 to 3]
Measured values and calculated values for the coated flaky glasses of Reference Examples 1 to 3 are shown in Table 3.

[Resin molded product]
[Examples 1-2, Comparative Examples 1-3]
The resin molded products of Examples 1 to 2 and Comparative Examples 1 to 3 were molded by the following method. Polycarbonate (Iupilon S3000F, manufactured by Mitsubishi Engineering Plastics Co., Ltd.) was used as the matrix resin. The coated glass flakes and polycarbonate were uniformly mixed in the desired proportions. For example, in Example 1, they were uniformly mixed so that the amounts were 40% by mass and 60% by mass, respectively. The obtained mixture was kneaded using an extrusion molding machine (KZW15-30MG, manufactured by Technovel Co., Ltd., molding temperature: 265 to 270°C) under molding conditions for polycarbonate, and was coated with polycarbonate as a matrix resin and as a reinforcing filler. A resin composition containing flaky glass was obtained. Note that no stabilizer or antioxidant was added. This resin composition was molded using an injection molding machine (manufactured by Nissei Jushi Kogyo Co., Ltd., HM7) to obtain a resin molded product.

[Reference examples 1 to 3]
Examples 1 to 2 and Comparative Examples 1 to 3, except that polyamide 66 (manufactured by Toray Industries, Inc., Amilan 3001N), which is more difficult to decompose with alkali components than polycarbonate, was used as the matrix resin, and the molding conditions were changed to polyamide 66. Resin molded products of Reference Examples 1 to 3 were obtained in the same manner as in the above.

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

<Measurement of particle size distribution by laser diffraction/scattering method>
Measurement of particle size distribution by laser diffraction/scattering method was performed on the residual glass flakes generated when calculating the content of glass flakes in the resin composition. Specifically, each glass flake was dispersed in water and the particle size distribution was measured using a laser diffraction particle size distribution measuring device (manufactured by Microtrac Bell Co., Ltd., model: MT3300EX, measurement mode: HRA). From the measurement results, the D50 value of the glass flakes in the resin composition was read. In addition, in the particle size distribution, the particle size corresponding to a volume accumulation of 50% from the smaller particle size side was defined as D50. The results are shown in Tables 2 and 3.

<Evaluation of the degree of decomposition of matrix resin>
The degree of decomposition of the matrix resin in the resin molded product was evaluated by measuring the melt flow rate (MFR) of the resin composition. MFR is known as a parameter representing a measure of the molecular weight of a resin. Generally, MFR is expressed as the amount of resin that flows out from an orifice in 10 minutes when melted resin is held in a cylinder and an appropriate load is applied to the resin. MFR is a measure of the viscosity of the molten resin, but is also related to 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, the MFR was measured according to JIS K 7210 at a temperature of 270° C. and a load of 2.16 kg. The results are shown in Tables 2 and 3.

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

As shown in Table 3, in Reference Examples 1 to 3 in which polyamide 66, which is more difficult to decompose with alkali components than polycarbonate, was used as the matrix resin, the MFR increased as the content of coated glass flakes in the resin composition increased. It showed a general trend of decreasing. On the other hand, as shown in Comparative Examples 1 and 2 in Table 2, when polycarbonate, which is easily decomposed by alkaline components, is used as the matrix resin, the content of coated glass flakes in the resin composition increases. The MFR showed a tendency to increase as time progressed. Although omitted in Table 2, a resin composition with a lower content of flaky glass in the resin composition than Comparative Example 1 (for example, 20% by mass) showed a lower MFR than Comparative Example 1.

As shown in Table 2, in Examples 1 to 2 and Comparative Examples 2 to 3, the content of the coated flake glass in the resin composition was as high as 40% by mass, and the resin composition was under conditions that easily caused decomposition. Ta. Nevertheless, Examples 1 and 2 had lower MFRs than Comparative Example 2. This is presumed to be because in Examples 1 and 2, the adhesion rate of the surface treatment agent on the coated glass flakes was 5% by mass or more, which suppressed the decomposition of the polycarbonate as the matrix resin. In fact, in Examples 1 and 2, the maximum tensile strength of the resin molded product was superior to that in Comparative Example 2. On the other hand, in Comparative Example 2, when the polycarbonate and the coated flake glass were kneaded under high temperature during extrusion molding, the decomposition of the polycarbonate was caused by the trace amount of alkali metal contained in the flake glass, which is E glass. It is assumed that it has progressed. Furthermore, in Comparative Example 3, the resin did not sag, making it impossible to measure MFR. This is because in Comparative Example 3, when the resin was held at a high temperature where the polycarbonate melted, the excess binder component present on the coated glass flakes melted and flowed out near the adhesive interface with the polycarbonate, causing the polycarbonate to melt. It is presumed that this is because the excessive reaction caused an increase in viscosity that could not be measured under the MFR measurement conditions. In addition, in Comparative Example 3, the adhesion rate of the surface treatment agent on the coated glass flakes was too high at 13.0% by mass, so the bond between the coated glass flakes became too strong, and as a result, the coated flakes were bonded to each other during extrusion molding. The dispersibility of the glass was reduced. In addition, excessive adhesion of the surface treatment agent inhibited adhesion and deteriorated mechanical properties. On the other hand, in Examples 1 and 2, since the adhesion rate of the surface treatment agent on the coated glass flakes was less than 10% by mass, the decrease in the dispersibility of the coated glass flakes was suppressed, and the mechanical properties is assumed to have been maintained. In fact, in Examples 1 and 2, the maximum tensile strength of the resin molded product was superior to that in Comparative Example 3.

Although omitted in Table 2, in Examples 1 and 2, the maximum bending strength and bending elastic modulus of the resin molded products measured according to JIS K7171 were good values. The maximum bending strength of the resin molded product of Example 1 was 164 MPa, and the maximum bending strength of the resin molded product of Example 2 was 154 MPa. The flexural modulus of the resin molded product of Example 1 was 7910 MPa, and the flexural modulus of the resin molded product of Example 2 was 7860 MPa.

When the flaky glass of the present invention is 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, and improve the mechanical properties and appearance of the resin molded product. It can be applied to a variety of applications. For example, the resin composition containing the coated flaky glass of the present invention and a thermoplastic resin is suitably used in the fields of automobiles, electrical machinery and electronic parts, and the like. More specifically, by using polycarbonate or the like as the thermoplastic resin, it can be applied to engineering parts.

1 Flake glass 11 Molten glass base 12 Fireproof kiln tank 15 Blow nozzle 16 Hollow glass membrane 17 Press roll 21 Pipe 22 Rotating cup 23 1 set of annular plates 24 Annular cyclone collector

Claims (7)

flaky glass,
a surface treatment agent that covers at least a portion of the surface of the glass flake;
A coated flake glass comprising:
The content ratio of the surface treatment agent in the coated flaky glass is 5% by mass or more and less than 10% by mass,
Coated flake glass. The flaky glass has an average thickness of 0.1 to 1.0 μm and an average particle size of 0.1 to 2000 μm,
The coated glass flake according to claim 1. The flaky glass is expressed in mass%,
52≦ _SiO2 ≦56
12≦Al ₂ O ₃ ≦16
16≦CaO≦25
0≦MgO≦6,
0≦( _Na2O + _K2O )≦2
5≦B ₂ O ₃ ≦13
0≦ _F2 ≦0.5
Contains the ingredients of
The coated glass flake according to claim 1. Used as a filler to reinforce resin molded products containing polycarbonate as a matrix resin.
The coated glass flake according to claim 1. matrix resin;
The coated flake glass according to any one of claims 1 to 4,
including,
Resin composition. the matrix resin is a thermoplastic resin;
The resin composition according to claim 5. the thermoplastic resin is polycarbonate;
The resin composition according to claim 6.

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