JPS6022445B2 - Laminated mica material and laminated mica prepreg material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a composite mica material and a composite mica prepreg material.

Conventionally, laminated mica is produced by heating muscovite to around 800°C to swell it, and then crushing it in water by wading in water or using a jet stream to obtain a particle size of about 0.2 mm. Mica foil, which is made from slurry of mica flakes as small as a proboscis, using a fourdrinier machine commonly used for paper making, is commonly used as calcined laminated mica, and phlogopite is also used in water. The slurry is made by grinding mica flakes into small mica particles with a particle size of about 2 ribs, and is made into a mica foil using a reami-type paper machine, which is generally used for paper making. Ta.

It is not possible to industrially grind fired mica thinly into 5 to IQ cape angles, and fine cracks are generated within the mica flakes when the crystal water of fired mica is released. The strength of the piece is low, the effect as a reinforcing material is small, and the density of fired laminated mica foil is 1.
3-1. Hina/There are a lot of voids in the mica foil.For example, in order to make a prepreg material, a large amount of thermosetting resin is required. It contained a large amount of resin and had poor mechanical and electrical properties. On the other hand, although phlogopite has slightly better heat resistance than muscovite, its electrical properties are inferior, so it cannot be used for insulation in high-voltage equipment such as generators.

On the other hand, unfired mica that has been crushed into smaller pieces can reduce the amount of thermosetting resin composition when processed into a laminated mica product compared to finely crushed fired laminated mica, but the mechanical and electrical properties are Insufficient compared to peelable mica products.

In order to solve these shortcomings, U.S. Samica Corporation (U.S.
S. SAMICA Corporation),
An unfired laminated mica called Micaniteo has been developed. Micaite 0' is obtained by crushing unfired muscovite flakes in water using ultrasonic energy, and its particle size distribution is shown in Table 1 along with the values of commonly used aggregate mica. . Table 1 Particle size distribution of Micanaite U and aggregate mica (general) *1 The numbers in the table are expressed as weight percentages.

*2 Source, U. S. SAMICA Corporation
on's catalog Mica Nite D is an unfired laminated mica, but it has a strong tensile strength of 0.7 to 1.3 k9f/ground without using any thermosetting resin composition. Although the density is high and excellent at 1.6 to 1.7 g/, it has a drawback due to the particle size distribution shown in Table 1.

Since Micaite Kawama uses large mica flakes, the reinforcing effect of the mica flakes is large, and the mechanical properties of mica products processed with this are improved, but on the other hand, large mica flakes alone cannot fill the technical details. However, after long-term deterioration, it had the disadvantage that its properties, especially its electrical properties, were inferior to those of peelable mica products. Peeled mica products are pieces of mica that are peeled off by hand and have a diameter of about 5 mm or more and a thickness of 30 to 50 m. Because of their large size, they must be made using a wet paper machine like laminated mica. It cannot be applied by hand or manufactured by semi-automated machines.

Peelable mica products are more expensive than laminated mica products because peelable mica is expensive and difficult to mass produce through mechanization. Peelable mica products use larger mica pieces than conventional laminated mica, so even after the thermosetting resin composition has deteriorated, the large mica pieces act as an insulator, so they are excellent even after long-term deterioration. In order to take advantage of the features of both peel-off mica products and laminated mica products, it has been devised to use them in combination.For example, as in JP-A-53-5050, a laminated mica material is laminated on both sides of the peel-off mica material. Although the thickness accuracy of the peel-off mica product is better than that of the peel-off mica product, its properties are lower than peel-off mica alone, especially after long-term deterioration, and it cannot be superior to either of the two.

The present invention overcomes these drawbacks. In the present invention, 2 to 25 parts by weight of mica flakes having a particle size of 1.7 or more and an aspect ratio of 150 or more obtained by crushing unfired mica are used. 20 to 6 parts by weight of mica lime chips with a size of more than 1.7 ribs and an aspect ratio of 150 or more, particle size of 0.25 or more 1. Less than the proboscis and the aspect ratio is 1
20 to 40 parts by weight of mica lime chips with a particle size of 0 or more and a particle size of 0
．． A laminated mica material obtained by adhering a laminated mica obtained by sanding a slurry containing 10 to 3 parts by weight of mica scale pieces having less than 25 ribs and an aspect ratio of 100 or more to bag batting material, and unfired mica and pulverization. Two or more pieces of mica lime with a grain size of 1.7 feet or more and an aspect ratio of 150 or more obtained by
25 parts by weight, 20 to 6 parts by weight of mica flakes with a particle size of 1.0 to 1.7 ribs and an aspect ratio of 150 or more, 1. A slurry containing 20 to 4 parts by weight of mica flakes having an aspect ratio of 100 or more and less than 0.25 grain size and 10 to 3 parts by weight of mica flakes having a grain size of less than 0.25 and an aspect ratio of 100 or more. The present invention relates to a mica pre-preg material obtained by impregnating or coating a thermosetting resin composition on mica obtained by paper-making, adhering it to a hair batting material as needed, and semi-curing it.

In the present invention, the aspect ratio refers to the diameter of the mica flakes and the thickness of the mica flakes, and the particle size distribution was calculated by wet classification using a standard analytical sieve and then measuring the weight after drying. .

As a pulverizing method for pulverizing the unfired mica to the particle size distribution and aspect ratio of the present invention, methods such as those disclosed in Tokko 1984-So9 No. 9 and Tsubaki Kai 1983-39 Ban 4 are adopted.

These methods are excellent methods in which a large aspect ratio and a desired particle size distribution can be easily obtained. Particle size 1.7
If the proportion of mica flakes with an aspect ratio of 150 or more above the ribs exceeds 25 parts by weight, the reinforcing effect of the mica flakes will be large and the mechanical properties will improve, but there will be variations in electrical properties, especially variations in dielectric breakdown voltage. growing.

Furthermore, when the content is 2 parts by weight, the mechanical properties are lower than those using peelable mica.

Furthermore, mica flakes having a particle size of 1.7 or more and an aspect ratio of less than 150 have poor mechanical properties and electrical properties.

Also, the particle size is 1. If the amount of mica flakes with an aspect ratio of less than 1.7 and an aspect ratio of 150 or more exceeds 6 parts by weight, the electrical properties of the insulating layer will vary, and if it is less than 2 parts by weight, the reinforcing effect of the mica flakes will be small. Furthermore, if the aspect ratio is less than 150, the sheet strength of the unfired laminated mica made without using a thermosetting resin composition will be low, making it difficult to handle the unfired laminated mica. Become.

Particle size 1. The aspect ratio of the mica limestone of Keiman is 10.
At zero heat, the sheet strength of the unfired laminated mica made without using a thermosetting resin composition becomes low, making it difficult to handle the unfired laminated mica, and also causing dielectric breakdown among electrical properties. Voltage drops. Particle size 0.25 skin or more 1.
If the amount of mica flakes with an aspect ratio of 100 or more exceeds 4 parts by weight, the mechanical properties will deteriorate, and if it is less than 2 parts by weight, the electrical properties, especially the dielectric breakdown voltage, will decrease. Less than 0.25 side and aspect ratio is 10
If the amount of mica flakes exceeds 3 parts by weight, the mechanical properties will deteriorate, and if the content is 1 part by weight, not only will the long-term deterioration characteristics among electrical properties deteriorate, but also the voids in the mica flakes will deteriorate. A large amount of thermosetting resin composition is required to fill the area.

The backing material used in the present invention is not particularly limited, and woven fabrics, nonwoven fabrics, films, etc. made of organic or inorganic materials such as polyester, polyamide, glass, etc. may be used in combination if necessary, and these may be used in combination with glass yarn, polyester, etc. There is no problem in combining fiber yarn, etc.

The method of impregnating or coating a thermosetting resin composition is to melt the thermosetting resin composition by heating, or dissolve it in a solvent such as methyl ethyl ketone, acetone, or methanol, and apply it using a spray nozzle, brush coating machine, etc. Although it is done using a general coating machine, there is no particular restriction.

The semi-cured composite mica prepreg material of the present invention may be provided with a backing material if necessary, but may not have a backing material.

Normal conditions are used for semi-curing after impregnation or coating, and there are no particular restrictions.

Unfired mica refers to mica that is not subjected to firing treatment, as well as paper contained in mica such as scrap mica and cut mica.
This refers to mica in which organic components such as wood and fibers have been completely removed by combustion in the air at a temperature that does not dehydrate mica crystal water (approximately 600 qo or less) to a temperature that dehydrates mica crystal water below 1/a.

If fired mica is used instead of unfired mica, mechanical properties such as bending strength and bending elastic modulus are undesirably reduced.

There are no particular restrictions on the method for forming mica flakes into a composite mica, and the method is usually to form a slurry of 0.5 to 2% by weight, and then use a fourdrinier type, round silk type, or other paper machine.

The thermosetting resin composition in the present invention includes a curing agent,
Epoxy resin compositions, unsaturated polyester resin compositions, etc. containing surfactants, solvents, reactive solvents, etc. are used, and there are no particular limitations.

The present invention will be explained below with reference to Examples.

Example 1 Table 2 *All sheet weights were 20 mm.** The above mica assembly was obtained by making a 1% by weight mica slurry in which mica flakes were dispersed in water using a remesh paper machine.

Table 3: Epoxy resin composition The epoxy resin composition shown in Table 3 heated to 60 oo of laminated mica 1 shown in Table 2 was coated at 10 coats per second, and the glass cloth WE05 manufactured by Nitto Boseki ■ (3 herons/final) was coated. The pieces were bonded together as a sheet of rhombus, heated at 80 o'clock for 1 hour, and semi-cured to obtain a laminated mica prepreg material.

After cutting this into a tape of 3 broadside width, 9.5 legs x 3
6.5 skin x length 1000 Wrap it around the side conductor (made of copper) 8 times, overlapping half of it, heat it to 100 ° C., press it, and raise it to 170 qo while flowing the above epoxy resin composition in the laminated mica prepreg material. The coil was heated and cured (for 3 hours) to produce a coil with an insulating layer of thickness 3. Four coils were manufactured, two were tested under normal conditions, and a thermal deterioration test (130qo
After 1 hour), two tests were performed. In the test, the dielectric breakdown voltage was measured at a heating rate of V/sec, followed by a four-point bending test (outer span: 550 ribs, inner span: 25 bowers, test speed: 5 ribs/min). The insulating layer was heated at 60,000 for 2 hours to determine the amount of epoxy resin composition. The results are shown in Table 4 as average values. Example 2 Ten coats of the epoxy resin composition shown in Table 3 heated to 600° were applied to laminated mica 2 shown in Table 2, and glass cloth (3 acids/me) was laminated as a rhombus material and the mixture was heated to 8000°C. It was heated for a period of time and semi-cured to form a laminated mica prepreg material.

Using this, four coils were manufactured using the method described in Example 1, and the results were measured under the same conditions as Example 1. The average values are shown in Table 4.
It was shown to. Example 3 Ten coats of the epoxy resin composition shown in Table 3 heated to 60°C were applied to Laminated Mica 3 shown in Table 2, and glass cloth (3 spots/pillow) was laminated as a backing material with 8 pins. It was heated for 1 hour and semi-cured to obtain a composite mica prepreg material.

Using this, four coils were manufactured using the method described in Example 1, and the results were measured under the same conditions as Example 1. The average values are shown in Table 4.
It was shown to. Comparative example 1 60q for laminated mica 4 listed in Table 2
10 coats of the epoxy resin composition listed in Table 3 heated to 800° C., mixed with glass cloth (3 thin/thin) as a hair dressing material, heated at 800° C. for 1 hour, semi-cured, and made into mica. It was made into a prepreg material.

Using this, four coils were manufactured by the method described in Example 1 and measured under the same conditions as in Example 1, and the results are shown in Table 4 as average values. Comparative Example 2 Sheet 5 shown in Table 2 was coated with 10 coats of the epoxy resin composition shown in Table 3 heated to 60°C, and glass cloth (W
E05) (3beard/fu) is pasted as a backing material 800
0 for 1 hour and semi-cured to obtain a mica prepreg material. Using this material, 4 coils were made by the method described in Example 1.
This was manufactured and measured under the same conditions as in Example 1, and the results are shown in Table 4 as average values.

Table 4 Coil characteristics Example 4 Two strings of the epoxy resin composition shown in Table 3 heated to 6000 were applied to the assembled mica shown in Table 2, and glass cloth (WE05) (35 g/〆) was used as a hair dressing material. They were laminated together at 80 mils and semi-cured at 0 heat for 1 minute to form a laminated mica material.

After cutting this into a tape with a width of 3 cm, 9.5 skin x 3
It was wrapped around a 6.5 willow x 1,000 skin conductor (made of copper) 8 times, half overlapping, and then the taped part was pressure molded to a thickness of 3 columns. This white coil was degassed in a vacuum container at a pressure of 1 x 10-2 Hg for 30 minutes, and then the epoxy resin composition shown in Table 3 heated to 80 qo was injected to immerse the white coil. After 1 hour, the vacuum container was brought to normal pressure with the bond still in place, and the white coil was removed and heated to 170℃.
It was cured at ℃ for 3 hours to produce a coil with an insulating layer 3 times thick. Four coils were manufactured and measured under the same conditions as in Example 1, and the results are shown in Table 5 as average values. Example 5 Mica laminated 2 shown in Table 2 was processed into mica laminated under the same conditions as in Example 4.

Four coils were manufactured under the same conditions as in Example 4 and measured under the same conditions as in Example 1, and the results are shown in Table 5 as average values.

Comparative Example 3 Mica laminated 4 shown in Table 2 was processed into mica laminated under the same conditions as in Example 4.

Four coils were manufactured under the same conditions as in Example 4 and measured under the same conditions as in Example 1, and the results are shown in Table 5 as average values.

Table 5 Characteristics of coils Coils that do not contain mica particles with a wind strength of less than 1 have poor electrical properties, and furthermore, their electrical properties deteriorate significantly due to long-term thermal deterioration. has poor mechanical properties and cannot significantly exceed those using conventional fired laminated mica.

Claims (1)

[Claims] 1. 2 to 2 pieces of mica flakes with a particle size of 1.7 mm or more and an aspect ratio of 150 or more obtained by crushing uncalcined mica.
5 parts by weight, 20 to 60 mica flakes with a particle size of 1.0 mm or more but less than 1.7 mm and an aspect ratio of 150 or more.
20 to 40 parts by weight of mica flakes with a particle size of 0.25 mm or more and less than 1.0 mm and an aspect ratio of 100 or more and a particle size of less than 0.25 mm and an aspect ratio of 1.
A laminated mica material obtained by bonding laminated mica obtained by paper-making a slurry containing 10 to 30 parts by weight of mica scale pieces of 0.00 or more to a backing material. 2. 2 to 2 pieces of mica flakes with a particle size of 1.7 mm or more and an aspect ratio of 150 or more obtained by crushing unfired mica.
5 parts by weight, 20 to 60 parts by weight of mica flakes with a particle size of 1.0 mm or more and less than 1.7 mm and an aspect ratio of 150 or more, and 20 to 60 parts by weight of mica flakes with a particle size of 0.25 mm or more and less than 1.0 mm and an aspect ratio of 100 or more. 20 to 40 parts by weight of mica flakes with a particle size of less than 0.25 mm and an aspect ratio of 10
A composite mica obtained by paper-making a slurry containing 10 to 30 parts by weight of 0 or more mica scale pieces, impregnated or coated with a thermosetting resin composition, adhered to a backing material as necessary, and semi-cured. Mica prepreg material.