JPH0784703B2 - Glass cloth processing method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for treating a glass cloth used for a composite material such as a laminate obtained by impregnating a resin and then molding the resin.

(Prior Art) A composite material using glass cloth, in particular, a laminate obtained by impregnating with a resin and then molding is manufactured as follows. First, a glass cloth is surface-treated with an organic silane compound in order to improve the performance of the intended laminated plate, and then a so-called treated glass cloth which is surface-treated with an organic silane compound is selected according to the purpose. The resin thus obtained is impregnated by various methods and then heat-treated to produce a semi-cured prepreg, which is cut into a predetermined shape, and a plurality of the prepregs are stacked and hot pressed.

In addition, in addition, in the case of a copper clad laminate used for a printed wiring board, such as a glass / epoxy copper clad laminate or a glass / polyimide copper clad laminate,
At the time of hot pressing, the copper foil is laminated on one side or both sides and hot pressing is performed.

Conventionally, among the applications using glass cloth, the composite material containing glass cloth used for general structural members has been desired to have improved mechanical properties such as bending strength and impact resistance. In addition, it has been strongly desired for laminated boards for printed wiring boards to have improved heat resistance and dimensional stability. It is also known that the chemical affinity and physical impregnation of the glass cloth and the resin have a great influence on these mechanical properties, thermal properties, dimensional stability and other properties. It was

For example, when the affinity between resin and glass surface is insufficient,
If the resin is not sufficiently impregnated between the yarns of the glass constituting the glass cloth or between filaments, the mechanical properties will deteriorate, and the interface between the glass and resin layer at high temperatures (blister) or It has been known to cause peeling (measling) of the resin layer at the entanglement point of the warp and weft of the yarn.

On the other hand, it is also known that a method of treating glass cloth with a silane coupling agent is effective for uniformly impregnating the glass cloth with the resin and for improving the affinity between the glass cloth and the resin. Attempts have been made to improve the types of silane coupling agents and the formulation conditions.

(Problems to be Solved by the Invention) However, even if the chemical treatment method for the glass surface of the glass cloth is improved as described above, satisfactory results have not yet been obtained, and further improvement is desired. Was there.

The object of the present invention is to eliminate the drawbacks of the prior art.

That is, the first object of the present invention is to provide a glass cloth treating method for producing a glass cloth excellent in resin impregnation property.

A second object of the present invention is to provide a composite material obtained by impregnating a glass cloth with a resin and then molding the composite material.
The purpose of the present invention is to provide a method for treating glass cloth for significantly improving mechanical properties.

(Means for Solving Problems) The inventors of the present invention have conducted extensive studies in order to solve such problems, and as a result, impregnated the glass cloth with a resin having a specific frequency of vibration. The present invention has been achieved by finding that the property is improved.

That is, the gist of the present invention is a method of treating a glass cloth for resin impregnation, which comprises bringing a vibrator vibrating at a frequency of 10 KHz to 70 KHz into contact with the glass cloth.

The present invention will be described in detail below.

The glass component of the glass fiber constituting the glass cloth used in the present invention may be any glass component, but for example, E glass, C glass, S glass and the like are preferable, and are particularly suitable for the glass cloth used for printed wiring boards. As the glass, non-alkali glass E glass is preferable.

As the fiber diameter of the glass fiber constituting the glass cloth used in the present invention, any fiber diameter can be used as long as the glass cloth can be woven, but it is preferably in the range of several microns to several tens of microns.

The glass cloth used in the present invention is obtained by subjecting a glass yarn obtained by combining a plurality of such glass fibers to a warping step and a sizing step, and then weaving.

The woven structure of the glass cloth used in the present invention may be any other than plain weave, twill weave, satin weave, triaxial weave and the like.

The number, thickness, and weight per unit area of the warp and weft of the glass cloth used in the present invention correspond to the Japanese Industrial Standard R-3414 and the US military standard (MIL standard). However, the present invention is not limited thereto, and any one can be used.

The thickness of the glass cloth that meets these standards is about 20 to about 300 μm, and the weight is about 2
It is from 0 g to about 350 / m ² .

Further, as the glass cloth used in the present invention, not only the glass cloth in the range that does not correspond to these standards,
A woven fabric made of glass fibers and fibers other than glass fibers, for example, a mixed weave of glass fibers / carbon fibers, a mixed weave of glass fibers / organic fibers, a cloth made of a mixed weave of glass fibers / ceramic fibers, and the like may be used.

The glass cloth referred to in the present invention includes a glass cloth at a stage where a sizing agent necessary for weaving is adhered (hereinafter referred to as a raw machine), a glass cloth at a stage where the sizing agent is removed by a wet process or a dry process (hereinafter referred to as cleaning). Glass cloth which is surface-treated with organic silane compound (hereinafter referred to as silane-treated cloth), etc.

The sizing agent referred to here is a sizing agent (generally referred to as a primary binder) that is applied in the spinning process that is the process of manufacturing glass fibers, or a warp in the sizing process that is one of the glass cloth manufacturing processes. Examples of sizing agents (generally referred to as secondary binders) applied to glass fibers include starch, surfactants, lubricants, synthetic oils, povals, acrylic polymers, etc. as sizing agents. To be

As a method of removing the sizing agent, there are a method of removing by heating and burning (dry method) and a method of cleaning and removing by smelting (wet method), and the dry method is usually adopted. The conditions of the dry method include conditions in which the glass cloth is continuously passed through a furnace at about 600 ° C, or the glass cloth is treated batchwise for several tens of hours in a furnace at 350 to 400 ° C.

The organic silane compound is represented by the general formula RnSiX _(4-n) . In this formula, X is an arbitrary monovalent hydrolyzable group such as a halogen atom, an alkoxy group or an acyloxy group, and n is 1 to 3. When n is 1 or 2, X's may be the same or different. R is a group having at least one carbon atom, and the hydrogen atom bonded to the carbon atom has reactivity such as an amino group, an epoxy group, a mercapto group, a vinyl group, and an acryl group in addition to an alkyl group and a phenyl group. It may be substituted with a functional group.

The organosilane compound may be used as a mixture of two or more kinds.

Typical organic silane compounds represented by the above general formula include, for example, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β-
(Aminoethyl) -γ-aminopropyltrimethoxysilane, N-β- (N-vinylbenzylaminoethyl) -γ
Examples include -aminopropyltrimethoxysilane, γ- (phenylamino) propyltrimethoxysilane, phenyltrimethoxysilane, and methyltrimethoxysilane.

These organic silane compounds are usually dissolved in an aqueous solution or an organic solvent such as alcohols, ketones, glycol ethers or the like to have a concentration of about 0.01 to 5% by weight and used. As a method of applying such an organic solvent solution of an organic silane compound to a glass cloth as a surface treatment agent,
Any known method such as a dipping method, a spraying method and a gasification method can be adopted.

A commonly used dipping method is to dip glass cloth in an organic solvent solution of an organic silane compound at a temperature close to room temperature for several seconds, squeeze it with a mangle, and then dry-cure at 80 to 180 ° C for several minutes. In the dipping method, the organic silane compound is usually added to 0.01 to 2.
A glass cloth provided with about 0% by weight is obtained.

The glass cloth to which the present invention is applied may or may not contain water or an organic solvent.

In the present invention, the vibrator vibrating at a specific frequency is brought into contact with the glass cloth, but the range of the frequency of the vibrator is 10 to 70 KHz, particularly preferably 15 to 50 KHz, and further preferably 20 to It is 40 KHz.

As a method of vibrating the vibrator, there is a method of transmitting ultrasonic waves generated by an ultrasonic oscillator to the vibrator through a converter. The output of the ultrasonic oscillator in this case is 30 to 7,000 Watts, especially 50 to 5000 Watts, and 150 to 3000 Watts.
Watts are preferred.

As such a device, for example, Seidensha Electronics Co., Ltd.
SONOPET (high-power ultrasonic welder) and Branson 8000 series ultrasonic welding machine.

The shape of the vibrator is preferably such that the surface of the glass cloth is not locally scratched, and for example, a wedge shape having a rounded portion in contact with the glass cloth or a cylindrical shape is desirable.

The material of the vibrator is preferably metal, such as gold,
Silver, titanium and the like are preferable.

The contact pressure at the contact between the vibrator and the glass cloth is
The linear pressure is preferably 0.02 to 70 g / cm, particularly 0.05 to 30 g / cm.

The glass cloth treatment method of the present invention may be either continuous or batch.

For the contact between the vibrator and the glass cloth, the position of the vibrator may be fixed and the glass cloth may be continuously run, or the glass cloth may be fixed and the vibrator may be moved along the glass cloth. .

In any case, the relative velocity between the vibrator and the glass cloth is preferably 0.5 to 100 m / min, particularly 2 to 70 m / min, and especially 5 to 50 m / min.

The atmosphere in which the glass cloth is brought into contact with the vibrator may be the atmosphere or may be under reduced pressure. It can also be carried out in water or an organic solvent solution or a mixed solution thereof.

The time when the glass cloth is brought into contact with the vibrator is not particularly limited. For example, during the step of removing the sizing agent or immediately after removing the sizing agent, or during the treatment with the organic silane compound or immediately after the treatment with the organic silane compound, the squeezing with the mangle is performed. It may be before or after the treatment.

Furthermore, the vibrator and the glass cloth may be contacted with each other a plurality of times in each step of manufacturing the glass cloth.

The temperature at which the vibrator is brought into contact with the glass cloth is not particularly limited. Moreover, the humidity when the vibrator is brought into contact with the glass cloth in the air is not particularly limited.

The glass cloth treating method of the present invention is to bring a vibrator into contact with the glass cloth. However, after the contacting step, the sizing agent of the glass cloth may be removed if necessary, or an organosilane compound may be used. May be processed.

For example, when a glass cloth having a sizing agent attached thereto is used, the sizing agent may be removed after contact with the vibrator and further treated with an organic silane compound. Further, when the vibrator is brought into contact with the glass cloth from which the sizing agent has been removed in advance, it may be subsequently treated with an organic silane compound.

In the method of the present invention, the highest effect tends to be obtained when the vibrator is brought into contact with the glass cloth surface-treated with the organosilane compound. Since an excellent effect can be obtained as compared with the method, the vibrator may be brought into contact with glass cloth at various stages of production, if necessary.

(Examples) The present invention will be described with reference to Examples. Each performance evaluation in the present invention was performed by the following methods.

(1) Dimensional stability; evaluated according to JIS C-6486.

(2) Immersion property; evaluated by light transmittance.

The transmitted light of a glass plate coated with triacetate film is measured. Then, a glass cloth is placed on a glass plate coated with triacetate film, and the intensity of transmitted light is measured 3 minutes after the epoxy resin is placed on the glass cloth.

(3) Heat resistance performance: After the laminated plate is boiled under normal pressure, immersed in a solder bath at 260 ° C for 30 seconds, and then removed from the laminated plate at the interface (blister) and glass cloth yarn entanglement point (mease). Examine the ring). The boiling time at which peeling occurs is defined as the heat resistant holding time. The sample piece shall be 50 mm x 50 mm.

Example 1, Comparative Example 1 Width 250 mm after removing the sizing agent of the glass cloth by heat treatment
Of glass cloth (plain weave, 42 warps / inch, 34 wefts / inch, weight 210 g / m ² ) of epoxy silane 0.2
After immersing in a wt% aqueous solution, squeeze with a mangle so that the amount of the aqueous solution becomes 30 parts by weight with respect to 100 parts by weight of glass cloth, and then dry curing with a hot air dryer at 150 ° C for 3 minutes to obtain a silane-treated glass cloth. .

While running this glass cloth at room temperature and atmospheric pressure at a speed of 10 m / min, a wedge-shaped vibrator made of titanium having a width of 400 mm was brought into contact with the linear pressure of 5 g / cm.

The oscillator frequency is 20 KHz, and the ultrasonic oscillator output is 1
It was 500W.

In order to evaluate the resin impregnation property of the glass cloth, the glass cloth before and after the contact with the vibrator was impregnated with epoxy resin.

As a varnish of epoxy resin, a 50 wt% solution of epoxy resin having FR-4 composition of NEMA standard was used. As shown in Table 1, the glass cloth obtained by the method of the present invention exhibits high impregnation performance.

Next, create a double-sided copper clad laminate for the printed wiring board,
The performance was compared.

Using the same epoxy resin varnish that was used to measure the impregnating property, we made a prepreg consisting of 45 parts by weight of resin and 55 parts by weight of glass cloth.
A 35 μm copper foil was overlaid and pressure-molded at 170 ° C. for 1 hour to prepare a laminate.

Table 1 shows the results of dimensional stability and heat resistance (boiling time).

As a comparative example, a resin was impregnated under the same conditions as those of the examples using a glass cloth not in contact with the vibrator, and then a laminated plate was prepared under the same molding conditions as those of the examples to measure the properties.

As is clear from Table 1, the laminated sheet using the glass cloth according to the method of the present invention has significantly improved heat resistance and dimensional stability as compared with the laminated sheet using the conventional glass cloth.

Example 2, Comparative Example 2 The same cleaned glass cloth used in Example 1 was dipped in a 0.1 wt% aqueous solution of aminosilane, and mangled so that the aqueous solution was 30 parts by weight with respect to 100 parts by weight of the glass cloth. Squeeze and then run this glass cloth at room temperature and atmospheric pressure at 15 m / min for a width of 400 mm at a line pressure of 12 g / cm.
The silver wedge-shaped oscillator of was contacted.

The oscillator frequency is 20 KHz, and the ultrasonic oscillator output is 1
It was 500W.

The obtained glass cloth was dried and cured with a hot air dryer at 150 ° C. for 2 minutes to obtain a treated glass cloth.

In the same manner as in Example 1, the impregnating property of the epoxy resin varnish on the glass cloth was examined. Further, a double-sided copper clad laminate was prepared by the same method as in Example 1 and its heat resistance and dimensional stability were examined.

As a comparative example, a resin was impregnated under the same conditions as those of the examples using a glass cloth not in contact with the vibrator, and then a laminated plate was prepared under the same conditions as those of the examples, and the properties were measured. The results are shown in Table 2.

The laminated sheet made of the glass cloth according to the method of the present invention has obviously improved heat resistance and dimensional stability as compared with the laminated sheet made of the glass cloth according to the conventional method.

Example 3, Comparative Example 3 A glass cloth having a width of 400 mm from which the sizing agent was removed by heat treatment (a plain weave with 44 warps / inch. Wefts 33 / inch, weight 209 g / m ² ) was placed in the atmosphere at room temperature. While traveling at 25 m / min, a wedge-shaped vibrator made of titanium with a width of 500 mm was brought into contact with the linear pressure of 12 g / cm.

The oscillator frequency is 20 KHz, and the ultrasonic oscillator output is 1
It was 000W.

The obtained glass cloth was immersed in a 0.15 wt% aqueous solution of aminosilane, and 100 parts by weight of the glass cloth was treated with an aqueous solution of 30%.
Squeeze with a mangle so that the weight is 14
Drying curing was performed at 0 ° C. for 2 minutes to obtain a treated glass cloth.

The glass cloth treated as described above was impregnated with an epoxy resin and dried at 150 ° C. for 5 minutes to prepare a prepreg.
Eight sheets were stacked and pressure-molded at 170 ° C. for 1 hour to obtain a laminated plate having a glass cloth content of 55% by weight.

The bending strength of the obtained laminated plate was measured according to JIS-K6911. Further, after leaving it in steam at 115 ° C. for 3 hours, the bending strength was measured.

As a comparative example, a glass cloth not in contact with the vibrator was impregnated with the epoxy resin in the same manner as in the example, and then a laminated plate was prepared, and its properties were measured. The test results are shown in Table 3.

Example 4, Comparative Example 4 A glass cloth having a width of 250 mm and having 2% by weight of a sizing agent adhered thereto (a plain weave has 42 warps / inch, wefts 34 / inch, and weight 209 g / m ² ) at room temperature and atmospheric pressure. While traveling at 10 m / min, a wedge-shaped vibrator made of titanium with a line pressure of 8 g / cm and a width of 400 mm was brought into contact.

Then, the glass cloth was subjected to heat treatment at 400 ° C. for 24 hours to remove the sizing agent from the glass cloth, and the surface of the glass cloth was silanized under the same conditions as in Example 3 to obtain a treated glass cloth. Using this, a double-sided copper-clad laminate was obtained under the same conditions as in Example 1.

As a comparative example, heat treatment and silane treatment were carried out in the same manner as in Example 4 using a glass cloth not in contact with the vibrator, and then a double-sided copper clad laminate was obtained. The performance of the laminate is shown in Table 4.

(Effect of the Invention) According to the method of the present invention, the impregnation property of the resin into the glass cloth is improved to a level that cannot be reached by the conventional processing method. Therefore, the performance (mechanical properties, thermal properties, dimensional stability) of the composite material obtained by impregnating the resin with the glass cloth obtained by the method of the present invention and then molding is improved.

[Brief description of drawings]

FIG. 1 is an example of a process of bringing a vibrator into contact with a glass cloth. 1 ... Ultrasonic oscillator, 2 ... Converter, 3 ... Transducer, 4
…… Glass cloth, 5 …… Roll.

Claims (1)

[Claims] 1. A method for treating glass cloth for resin impregnation, comprising bringing a glass cloth into contact with a vibrator vibrating at a frequency of 10 KHz to 70 KHz.