JP2022063290A - Glass cloth, prepreg, and printed wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a glass cloth with reduced bending while maintaining a thickness of 16 μm or less, and provide a prepreg and a printed wiring board in which the difference in signal propagation speed of a plurality of transmission lines is reduced.

SOLUTION: In a glass cloth with the thickness of 8 μm or more and 16 μm or less, which is made by weaving glass threads composed of multiple glass filaments as warps and wefts, an abundance ratio Y of the warp and weft in the longitudinal direction determined by the formula (1) of Y=F/(25000/G)×100 is 75% or more and 90% or less, and the sum of the thread width of warp and the thread width of weft is 380 μm or more and 500 μm or less (in the formula, F is the thread width (μm) of the weft, and G is the weft density (book/25 mm) of the weft).

SELECTED DRAWING: None

COPYRIGHT: (C)2022,JPO&INPIT

Description

The present invention relates to glass cloths, prepregs, and printed wiring boards.

In many printed wiring boards, a transmission line is formed of copper foil in an insulator layer composed of a glass cloth and a matrix resin composition.
The glass cloth used for the printed wiring board is formed by plain weaving glass threads in the warp and weft directions. Therefore, in the insulator layer composed of the glass cloth and the resin composition, the abundance ratio of the glass is high at the portion where the threads intersect, and the abundance ratio of the resin is high at the portion where the threads do not overlap or where there is no thread. Become.
Usually, there is a difference between the dielectric constant of the glass of the glass cloth and the dielectric constant of the resin composition. Therefore, it is known that there is a difference between the signal propagation speed in the transmission line passing through the portion where the abundance ratio of the glass is high and the signal propagation speed in the transmission line passing through the portion where the abundance ratio of the resin composition is high. Has been done. Therefore, in an electronic circuit that needs to synchronize a plurality of signals, there is a possibility that signal processing will be inconvenient when the arrival times of the signals are deviated.

With the development of the information and communication society in recent years, data communication and / or signal processing has come to be performed at high speed with a large capacity, and the speed of transmitted signals is increasing. Signal speed is 10 Gbps
The speed is increasing in the giga region such as 28 Gbps and 56 Gbps, and the higher the speed of the signal, the greater the influence of the above signal propagation speed difference, and the demand for reducing the signal propagation speed difference is increasing. There is.
Here, when a pair of wirings are formed on the same insulator layer, the signal propagation speed transmitted through each wiring is the dielectric between the portion where the abundance ratio of glass is high and the portion where the abundance ratio of resin is high as described above. Since the rates are different, it is known that the positional relationship between the transmission line and the glass cloth is affected. Therefore, Patent Documents 1 to 3 propose techniques for reducing changes in propagation speed caused by the positional relationship between the glass cloth and the transmission line.
Specifically, Patent Document 1 discloses a technique for adjusting the line width to 75% to 95% of the spacing between the threads of the glass cloth.
Patent Document 2 discloses a technique for matching the spacing between glass threads and the spacing between signal lines.
Patent Document 3 discloses a technique for reducing the distance between glass threads and the distance between wiring widths to 50%.

On the other hand, in order to increase the functionality, size and weight of digital devices in recent years, the printed wiring boards used are also required to be further reduced in size, thickness and density. As a method of miniaturization, thinning, and high density, the glass cloth used as a base material may be made thinner and the number of layers of the multilayer printed wiring board may be increased. Here, the thickness of the glass cloth is
In order to achieve high functionality, small size and light weight of the most advanced smartphones and wearable devices, it is required to be as thin as 16 μm or less, for example. Patent Documents 4 to 6 disclose a glass cloth having a thin thickness.

Japanese Unexamined Patent Publication No. 2014-130860 International Publication No. 2016/11320 International Publication No. 2017/159649 Japanese Patent No. 3756066 Japanese Patent No. 4446754 Japanese Patent No. 5936726

The glass thread constituting the glass cloth has a property that can cause bending. In particular, in a thin glass cloth, since a thinner glass thread is used as compared with a thick glass cloth, the thread widths of the warp and weft are generally narrow, and the warp and weft at the intersection of the warp and weft The contact area is small. Therefore, the mutual binding force between the warp and the weft becomes weak, and for example, in the process of manufacturing the glass cloth or the process of manufacturing the prepreg using the glass cloth, the parallelism of the rolls carrying the glass cloth is slightly deviated. If there is, there is a difference in the tension acting on the warp in the width direction, that is, in the CD direction. As a result, while the warp and weft originally intersect at a right angle, there is a problem that the weft is likely to be bent or bent.
In addition, in the process of manufacturing the prepreg, the load acts non-uniformly in the width direction on the glass cloth in the process of passing through a narrow slit to control the amount of resin adhered when the resin is impregnated and coated. , Has a problem that bending is likely to occur.

The bending becomes more remarkable as the thickness of the glass cloth becomes thinner and the number of filaments of the threads constituting the glass cloth decreases.
Therefore, as disclosed in Patent Documents 1 to 3, in the method of trying to reduce the signal propagation speed difference by the transmission line considering the arrangement of the glass threads, the positional relationship between the transmission line and the glass thread is caused by the bending of the glass thread. There is a problem that it is difficult to precisely control the signal propagation speed due to deviation and / or variation.

The glass cloth specifically disclosed in Examples 1 to 4 of Patent Document 4 is 100 m.
It is a glass cloth having an average value of 3 to 5 mm and a thickness of 10 to 12 μm, which is measured at 10 points every 10 m of a long glass cloth. Patent Document 4 discloses that the average value of the bending amount is small. However, since the amount of bending usually varies, if there is a part with large bending, a transmission line in which the signal propagation speed fluctuates greatly occurs, and there is a problem in signal processing in electronic circuits that need to synchronize multiple signals. Occurs.

The glass cloth specifically disclosed in Examples 1 to 5 of Patent Document 5 is 100 m.
The average value of the amount of bending of a long glass cloth measured every 10 m is 1 to 3 mm, and the thickness is 17 to 2.
It is a 1 μm glass cloth. In the glass cloth described in Patent Document 5, in order to improve the workability of small holes, adjacent threads are practically arranged without gaps. Therefore, it is necessary to use a glass thread having a large number of filaments, and it is difficult to reduce the thickness of the glass cloth.

The glass cloth specifically disclosed in the examples of Patent Document 6 is a thin glass yarn (BC3000, BC3750) having a mass of 1.65 × 10 ^-6 kg / m or less for both warp and weft.
, BC5000, lighter than BC6000) is used, and the yarn widths of the warp and weft are also narrow. Therefore, the mutual binding force at the intersection of the warp and weft is weak, and bending is likely to occur as in the conventional glass cloth.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a glass cloth in which bending is suppressed while maintaining a thickness of 16 μm or less.
Another object of the present invention is to provide a prepreg and a printed wiring board using the above glass cloth in which the difference in signal propagation speed of a plurality of transmission lines is reduced.

As a result of diligent studies to solve the above problems, the present inventors have determined the abundance ratio of warp and weft in the longitudinal direction.
Further, they have found that the glass cloth satisfying that the sum of the yarn width of the warp and the yarn width of the weft is within a specific range can suppress the occurrence of bending while maintaining the thickness at 16 μm or less. It came to be completed.
Further, the present inventors consider that the glass cloth is a printed wiring plate in which the abundance ratio of the warp and weft in the longitudinal direction is in a specific range and the bending amount of the warp and the spacing of the warp satisfy a specific relationship. In addition, it was found that the fluctuation of the signal propagation speed can be reduced because the distance in which the change in the abundance rate of glass in the insulator layer through which the transmission line arranged so as to be parallel to the warp and weft passes can be suppressed to be small. , The present invention has been completed.

That is, the present invention is as follows.
[1]
A glass cloth having a thickness of 8 μm or more and 16 μm or less, which is made by weaving a glass thread composed of a plurality of glass filaments as a warp and a weft.
Equation (1);
Y = F / (25000 / G) x 100 ... (1)
(In the formula, F is the thread width (μm) of the weft, and G is the weft density (book / 25 mm) of the weft.)
The abundance ratio Y of the warp and weft in the longitudinal direction, which is obtained in the above, is 75% or more and 90% or less.
A glass cloth in which the sum of the yarn width of the warp and the yarn width of the weft is 380 μm or more and 500 μm or less.
[2]
The elongation rate in the warp direction generated when a load of 5 N per 25 mm width is applied in the warp direction, and the width 2
The sum with the elongation rate in the warp and weft direction generated when a load of 5N per 5 mm is applied in the warp and weft direction is 0.
The glass cloth according to [1], which is 50% or less.
[3]
A glass cloth having a thickness of 8 μm or more and 16 μm or less, which is made by weaving a glass thread composed of a plurality of glass filaments as a warp and a weft.
Equation (1);
Y = F / (25000 / G) x 100 ... (1)
(In the formula, F is the thread width (μm) of the weft, and G is the weft density (book / 25 mm) of the weft.)
The abundance ratio Y of the warp and weft in the longitudinal direction, which is obtained in the above, is 75% or more and 90% or less.
A glass cloth in which the amount of warp bending is equal to or less than a value obtained by dividing a value of 10 times the weft spacing (mm) by 500 mm.
[4]
The glass cloth according to [3], wherein the amount of warp bending is equal to or less than a value obtained by dividing a value of 5 times the weft spacing (mm) by 500 mm.
[5]
The glass cloth according to [3], wherein the amount of warp bending is equal to or less than a value obtained by dividing a value 2.5 times the weft spacing (mm) by 500 mm.
[6]
The glass cloth according to [3], wherein the amount of warp bending is equal to or less than a value obtained by dividing a value of 1.0 times the weft spacing (mm) by 500 mm.
[7]
The sum of the yarn width of the warp and the yarn width of the warp is 380 μm or more and 500 μm or less, [3] to [
6] The glass cloth according to any one of.
[8]
The elongation rate in the warp direction generated when a load of 5 N per 25 mm width is applied in the warp direction, and the width 2
The sum with the elongation rate in the warp and weft direction generated when a load of 5N per 5 mm is applied in the warp and weft direction is 0.
The glass cloth according to [7], which is 50% or less.
[9]
The ratio of the cross-sectional height in the warp direction to the cross-sectional height in the weft direction is 90% or more and 110% or less.
The glass cloth according to [1] or [2].
[10]
The sum of the yarn width of the warp and the yarn width of the warp is 380 μm or more and 500 μm or less.
The ratio of the cross-sectional height in the warp direction to the cross-sectional height in the weft direction is 90% or more and 110% or less.
The glass cloth according to any one of [3] to [6].
[11]
The average mass per unit length of the warp is 1.4 x 10 ^-6 kg / m or more 1.8 x 10 ^-6 kg
Less than / m
The average mass per unit length of the weft is 1.8 x 10 ^-6 kg / m or more 4.0 x 10 ^-6 kg
/ M or less and
Any of [1] to [10], wherein the ratio of the average mass per unit length of the warp (weft / warp ratio) to the average mass per unit length of the warp is greater than 1.20 and 1.80 or less. The glass cloth described in Crab.
[12]
The average number of filaments of the warp and weft is substantially the same, and
The average filament diameter of the warp is 3.7 μm or more and 4.3 μm or less.
The average filament diameter of the weft is 4.2 μm or more and 5.3 μm or less.
The glass cloth according to any one of [1] to [10], wherein the ratio of the average filament diameter of the weft to the average filament diameter of the warp (weft / warp ratio) is 1.07 or more and 1.40 or less.
[13]
The average filament diameters of the warp and weft are substantially the same, and
The average number of warp filaments is 45 or more and 70 or less.
The average number of weft filaments is 55 or more and 80 or less.
The glass cloth according to any one of [1] to [10], wherein the ratio of the average number of filaments of the weft to the average number of filaments of the warp (weft / warp ratio) is larger than 1.25 and 1.50 or less.
[14]
A prepreg composed of the glass cloth according to any one of [1] to [13] and a matrix resin.
[15]
The prepreg according to [14], wherein the difference between the dielectric constant of the glass constituting the glass cloth at 10 GHz and the dielectric constant of the cured product of the matrix resin at 10 GHz is 3 or less.
[16]
The prepreg according to [14], wherein the difference between the dielectric constant of the glass constituting the glass cloth at 10 GHz and the dielectric constant of the cured product of the matrix resin at 10 GHz is 2 or less.
[17]
The prepreg according to [14], wherein the difference between the dielectric constant of the glass constituting the glass cloth at 10 GHz and the dielectric constant of the cured product of the matrix resin at 10 GHz is 1 or less.
[18]
A printed wiring board produced by using the prepreg according to any one of [14] to [17].

According to the present invention, it is possible to provide a glass cloth in which bending is suppressed while maintaining a thickness of 16 μm or less. When the glass cloth of the present invention is used as a printed wiring board, the deviation of the positional relationship between the glass thread and the transmission line can be reduced. Further, according to the present invention, it is possible to provide a prepreg and a printed wiring board having a small difference in signal propagation speed between a plurality of transmission lines.

It is a figure which shows the load-elongation curve which is the result of the elongation amount measurement of the 1017 style glass cloth, that is, the glass cloth with a thickness of 14 μm. It is a figure which shows the load-elongation curve of the glass cloth E obtained in Example 5. It is a schematic diagram which shows the thread width of the weft, and the spacing of the weft in the glass cloth of this embodiment. It is a schematic diagram which shows one form of the glass cloth of this embodiment, and is the figure which shows one form of a warp and weft. It is a schematic diagram which shows one form of the glass cloth of this embodiment, and is the figure which shows one form of a warp and weft. It is a schematic diagram which shows one form of the glass cloth of this embodiment, and is the figure which shows one form of a warp and weft.

Hereinafter, embodiments of the present invention (hereinafter referred to as “the present embodiment”) will be described in detail, but the present invention is not limited thereto, and various modifications can be made without departing from the gist thereof. Is.
Further, the dielectric constant in the present embodiment indicates a value measured in the 10 GHz band by the cavity resonator perturbation method (perturbation method cavity resonator / manufactured by Kanto Denshi Applied Development Co., Ltd.).

<Glass cloth>
(thickness)
The glass cloth of the present embodiment is a glass cloth having a thickness of 8 μm or more and 16 μm or less, which is made by weaving glass threads composed of a plurality of glass filaments as warps and wefts.
When the thickness is 16 μm or less, it is possible to increase the number of layers of the multilayer printed wiring board, and it is possible to increase the density of the transmission line while maintaining the thickness of the multilayer printed wiring board. It is preferable that the thickness of the glass cloth is thin, but as the thickness becomes thin, it is necessary to make the glass thread to be a thin thread, and the strength of the glass cloth is lowered and the bending of the eyes is likely to occur. When the thickness is 8 μm or more, the strength of the glass cloth can be maintained and the occurrence of bending can be suppressed.

(Warp occupancy rate)
In the glass cloth of the present embodiment, the presence ratio of the warp and weft in the longitudinal direction is 75% or more and 90% or less. The abundance ratio of the warp and weft in the longitudinal direction is also referred to as the warp and weft occupancy rate, which is a value Y obtained from the equation (1) and obtained by dividing the warp and weft yarn width by the weft spacing.
Y = F / (25000 / G) x 100 ... (1)
(In the formula, F is the thread width (μm) of the weft, and G is the weft density (book / 25 mm) of the weft.)
The thread width of the weft is an average value obtained by observing a glass cloth sample having a size of 100 mm × 100 mm from the surface with a microscope, determining the widths of all the wefts, and dividing the total by the total number of the wefts. At this time, if the thread width of the weft fluctuates within the sample, the width of the portion having the widest width is taken as the thread width of the weft.

One of the present embodiments is a glass cloth having a thickness of 8 μm or more and 16 μm or less, which is made by weaving a glass thread composed of a plurality of glass filaments as a warp and a weft.
Equation (1);
Y = F / (25000 / G) x 100 ... (1)
(In the formula, F is the thread width (μm) of the weft, and G is the weft density (book / 25 mm) of the weft.)
The abundance ratio Y of the warp and weft in the longitudinal direction, which is obtained in the above, is 75% or more and 90% or less.
A glass cloth in which the sum of the yarn width of the warp and the yarn width of the weft is 380 μm or more and 500 μm or less.
The glass cloth is also referred to as a glass cloth P.

(The sum of the thread width of the warp and the thread width of the weft)
In the glass cloth P of the present embodiment, the sum of the yarn width of the warp and the yarn width of the weft is 380 μm.
It is 500 μm or less, preferably 380 μm or more and 480 μm or less, and more preferably 400 μm or more and 480 μm or less.
When the sum of the thread width of the warp and the thread width of the weft is 380 μm or more, the contact area between the warp and the weft becomes large at the intersection of the warp and the weft, the friction area becomes large, and the mutual binding force becomes large. Becomes stronger and the bending of the eyes is suppressed.
When the sum of the warp width and the weft width is 500 μm or less, the mutual binding force between the warp and the weft at the intersection of the warp and the weft does not become too strong, and the warp and the weft become appropriate. Since there is room for movement, in a thin glass cloth having a thickness of 16 μm or less, when stress is applied, the warp and weft move from the intersection point as a base point, so that the stress is relaxed and the generation and breakage of wrinkles are suppressed.

Further, since the line width generally used for a multilayer wiring board or the like is about 0.1 mm, a transmission line arranged so as to be parallel to the weft in a glass cloth having a weft occupancy of 75% or more and 90% or less. Since the thread width of the weft is preferably 300 μm or less in order to suppress the change in the abundance rate of the glass of the insulator layer through which the warp passes, the sum of the thread width of the warp and the thread width of the weft is 500 μm.
It is preferably m or less.
When the sum of the yarn width of the warp and the yarn width of the weft is 380 μm or more and 500 μm or less, a glass cloth having no wrinkles or bending and excellent handleability can be obtained.

(Sum of growth rate)
The glass cloth of the present embodiment has an elongation rate in the warp direction generated when a load of 5 N per 25 mm width is applied in the warp direction and an elongation rate in the warp direction generated when a load of 5 N per 25 mm width is applied in the weft direction. The sum is preferably 0.50% or less.
The sum of the elongation rates is more preferably 0.48 or less, and the still more preferable range is 0.45 or less.
Here, the elongation rate of the glass cloth is a value obtained as follows.

The amount of elongation when tension is applied to the glass cloth in the warp direction or the weft direction is determined by JIS R342.
The glass test of 0 is measured by applying the general test method and the method described in the section of 7.4 tensile strength mutatis mutandis. In the method specified by JIS, a test piece having a width of about 30 mm and a length of about 250 mm is taken from the warp and weft directions of the woven fabric, and the threads at both ends of the test piece are loosened to a width of about 25 mm, and the width is about 150 m.
It is attached to the grip portion with a grip interval of m secured, and it is pulled at a pulling speed of about 200 mm / min to obtain the load at the time of breakage. In the present embodiment, the tensile test is performed under the same conditions as the above JIS specified method except that the tensile speed is set to about 10 mm / min and the width of the test piece to be collected is set to about 35 mm in order to improve the measurement accuracy. Do, the width of the glass cloth is 25 mm
The amount of displacement when a hit load acts of 5N is obtained, and the value obtained using the following equation (2) is defined as the "elongation rate of the glass cloth".
Elongation rate = {(interval under load-interval under no load) / interval under no load} x 100 (2)

As a result of investigating the relationship between the woven structure of the glass cloth and the susceptibility to bending, the present inventors have found that the "elongation amount in the initial deformation region" and the susceptibility to bending when tensile tension is applied. It was found that there is a correlation between them, and that when the "elongation amount in the initial deformation region" is made smaller than the specific range, the occurrence of bending is remarkably suppressed in the normal handling of glass cloth.

As shown in FIG. 1, 10 is often used for printed wiring boards as a conventional thin glass cloth.
The load-elongation curve which is the result of the elongation amount measurement of 17 styles, that is, the glass cloth with a thickness of 14 μm is shown.
The load-elongation curve of the 1017 style glass cloth is characterized by a larger elongation of the warp than the warp, with a low slope up to around 0-0.2% displacement and then gradually higher up to about 0.4%. After 0.4%, it swings up and becomes a constant inclination.
In the region where the inclination is low, there is a gap between the warp and the warp at the intersection of the warp and the warp, and the warp and the warp are not in sufficient contact with each other. It is reflected that it is pulled greatly until it becomes. The region where the next slope gradually increases is the region where the crimp unraveling of the warp is progressing with the increase in the crimp of the warp. After that, the region where the weft swings up and the inclination becomes constant is the region where the weft itself is stretched and elastically deformed.

As described above, the warp and weft of the 1017 cloth has an initial deformation region before elastic deformation in a very weak tensile tension range of up to 5N per 25 mm, and the amount of elongation in the initial deformation region is large.
Compared with the conventional glass cloth such as 1017 style, the glass cloth of this embodiment has a smaller amount of elongation in the initial deformation region. FIG. 2 shows the load-elongation curve of the glass cloth E obtained in Example 5. The glass cloth E of the present invention has a small elongation amount up to 5N even in the warp and weft direction.
The amount of elongation in the initial deformation region is kept small. This suggests that the warp and weft have a strong mutual binding force at the intersection of the warp and weft.
Thin glass cloth, especially glass cloth with a thickness of 16 μm or less, usually uses a thin glass thread having a filament diameter of 4.0 μm or less and a number of filaments of 50 or less in order to express the thickness. , Mutual binding force at the intersection of warp and weft is weak and it is easy to bend, but the sum of the elongation rates in the glass cloth is 0.50% or less.
It tends to be a glass cloth in which the occurrence of bending is suppressed by increasing the mutual binding force at the intersection of the warp and weft.

As described above, the sum of the elongation rate in the warp direction generated when a load of 5 N per 25 mm width is applied in the warp direction and the elongation rate in the warp direction generated when a load of 5 N per 25 mm width is applied in the warp direction is 0. By setting the content to 50% or less, the mutual binding force at the intersection of the warp and weft becomes high, and the glass cloth can be made into a glass cloth in which bending is unlikely to occur.
On the other hand, the lower limit of the sum of the elongation rates is preferably 0.30% or more, more preferably 0.33% or more, and further preferably 0.35% or more. When the sum of the elongations is 0.30% or more, the glass cloth having a woven structure is reversible in the strain due to the application applied to the glass cloth, and the structure of the glass cloth is reversible based on the intersection point of the warp and the weft. It is alleviated by changing to, and tends to suppress the occurrence and breakage of wrinkles.
When the sum of the elongation rates is in the range of 0.30% or more and 0.50% or less, a glass cloth having no wrinkles and bending and excellent handleability tends to be obtained.

Further, one of the present embodiments is a glass cloth having a thickness of 8 μm or more and 16 μm or less, which is made by weaving a glass thread composed of a plurality of glass filaments as a warp and a weft.
Equation (1);
Y = F / (25000 / G) x 100 ... (1)
(In the formula, F is the thread width (μm) of the weft, and G is the weft density (book / 25 mm) of the weft.)
The abundance ratio Y of the warp and weft in the longitudinal direction, which is obtained in the above, is 75% or more and 90% or less.
It is a glass cloth in which the amount of bending of the weft is equal to or less than the value obtained by dividing the value of 10 times the interval of the weft by 500 mm.
The above glass cloth is also referred to as glass cloth Q.

The amount of warp bending is preferably 5 times the weft spacing divided by 500 mm, and 2.5 times the weft spacing divided by 500 mm. It is more preferable that the value is 1.0 times the weft spacing divided by 500 mm or less. Here, the unit of "warp and weft spacing" in "a value obtained by dividing a value of 10 times, 5 times, 2.5 times, or 1.0 times the weft spacing by 500 mm" is mm.

The weft occupancy rate and the amount of bending are preferably 77% or more and 87% or less, and the amount of bending is preferably a value obtained by dividing 5 times the weft spacing by 500 mm, and the occupancy rate is 79. It is more preferably% or more and 85% or less, and the bending amount is 2.5 times the weft spacing divided by 500 mm, the occupancy rate is 80% or more and 84% or less, and the bending amount is 1. 0 times the value 5
It is more preferably less than or equal to the value divided by 00 mm.
The interval between the wefts in the present embodiment is the interval between the wefts constituting the glass cloth.
The weft spacing in the present specification also includes the yarn width itself. FIG. 3 shows a schematic diagram showing the spacing between the wefts in the glass cloth. a is the yarn width, and b is the spacing between the wefts.
Further, the weft spacing is obtained from the weft density G (book / 25 mm), and specifically, the weft spacing is calculated from 25 / G (mm) when the unit of the spacing is mm. When the unit of the interval is μm, it can be calculated from 25000 / G (μm).

The warp occupancy rate is 75% or more and 90%, and the amount of bending is equal to or less than the value obtained by dividing the value of 10 times the weft spacing by 500 mm, so that the printed wiring plate is parallel to the weft. Since the change in the abundance rate of the glass in the insulator layer through which the transmission lines arranged so as to pass is suppressed to a small extent, the fluctuation of the signal propagation speed tends to be reduced.

Here, when the warp and weft occupancy rate is 75% or more and 90%, if the amount of bending is less than or equal to the value obtained by dividing the value of 10 times the interval of the warp and weft by 500 mm, the transmission arranged so as to be parallel to the warp and weft. Keep the deviation between the line and the weft small, specifically, keep the size of the deviation from the weft of the transmission line to a range smaller than 0.5 times the interval between the wefts, and make the abundance ratio of the glass around the transmission line the same. The transmission line that can be maintained can be lengthened.
It is preferable that the amount of bending is small, and ideally, the amount of bending is 0, but it may be more than 0.

The “bending amount” in the present specification is Z _N (Z ₀ , Z ₁ ) defined by the following formula (I).
, And Z ₂ ), which has the maximum value.

Zn = | (Y _{N + 1} -Y _N ) / (X _{N + 1} -X _N ) | (I)
(In the equation, N is 0 to 2, and if the value of X _{N + 1} -X N is 0, then Z _N is assumed to be 0).

In the equation, X ₀ to X ₃ and Y ₀ to Y ₃ are (X ₀ , Y ₀ ), (X ₁ , Y ₁ ), (X ₂ , Y ₂ ), and (
It is expressed by a combination of X ₃ and Y ₃ ) and is defined as shown below.
A glass cloth consisting of a plurality of warps and a plurality of wefts, a prepreg, or a printed wiring board is used as a sample to be tested, the warp direction of the sample to be tested is the Y direction, and the direction perpendicular to the Y direction is the X direction. Regarding the weft extending from the first warp to the second warp among the first and second warps at both ends of the sample to be tested, the contact point between the first warp and the above weft is the origin (0,0). That is, the Y-axis and the X-axis to be (X ₀ , Y ₀ ) are defined. Further, the contact point between the second warp and the warp and weft is set as the end point (X3, Y3), and one of the points having the maximum value and the minimum value with respect to the coordinate Y of the warp and weft on the X _- axis and the Y _- axis is (X). ₁ , Y ₁ ) and the other (X ₂ )
, Y ₂ ), and in this case, (X ₀ , Y ₀ ), (X ₁ , Y ₁ ), (X ₂ , Y) on the warp and weft.
₂ ) and (X ₃ , Y ₃ ) are arranged in this order.

Hereinafter, with reference to FIGS. 4 to 6, the calculation methods for Z ₀ , Z ₁ , and Z ₂ are exemplified. Figure 4 ~
FIG. 6 is a schematic view showing one form of a warp and weft. The form of the warp and weft in the present embodiment is not limited to the form of the warp and weft of FIGS. 4 to 6.

In FIG. 4, the origin (X ₀ , Y ₀ ), the point where the maximum value of Y is taken (X ₁ , Y ₁ ), the point where the minimum value of Y is taken (X ₂ , Y ₂ ), and the end point (X 2, Y 2) are on the warp and weft. X ₃ , Y ₃ ) are arranged in this order. Z ₀ is calculated by substituting two adjacent points (X ₀ , Y ₀ ) and (X ₁ , Y ₁ ) into the above equation (I), and Z
₁ is calculated by substituting two adjacent points (X ₁ , Y ₁ ) and (X ₂ , Y ₂ ) into the above equation (I), and Z ₂ is two adjacent points (X ₂ , Y 2). Y ₂ ) and (X ₃ , Y ₃ ) are expressed in the above equation (I).
It is calculated by substituting into.

In FIG. 5, on the warp and weft, the origin (X ₀ , Y ₀ ), the point where the maximum value of Y is taken (X ₁ , Y ₁ ), the point where the minimum value of Y is taken (X ₂ , Y ₂ ), and the end point (X 2, Y 2). X ₃ , Y ₃ ) are arranged in this order, where (X ₂ , Y ₂ )
And (X ₃ , Y ₃ ) indicate the same coordinates. Z ₀ , Z ₁ , and Z ₂ can be calculated in the same manner as described in FIG. 4 above.
Since (X ₂ , Y ₂ ) and (X ₃ , Y ₃ ) indicate the same coordinates, Z ₂ takes a value of 0 with respect to the above equation (I).

In FIG. 6, the origin (X ₀ , Y ₀ ), the point where the maximum value of Y is taken (X ₁ , Y ₁ ), the point where the minimum value of Y is taken (X ₂ , Y ₂ ), and the end point (X 2, Y 2) are on the warp and weft. X ₃ , Y ₃ ) are arranged in this order, where (X ₀ , Y ₀ )
And (X ₁ , Y ₁ ) indicate the same coordinates, and (X ₂ , Y ₂ ) and (X ₃ , Y ₃ ) indicate the same coordinates, Z ₀ , Z ₁ , And Z ₂ can be calculated in the same manner as described in FIG. 4 above.
Since (X ₀ , Y ₀ ) and (X ₁ , Y ₁ ) indicate the same coordinates, Z ₀ takes a value of 0 with respect to the above equation (I), and Z ₂ is also 0. Take the value of.

While the bending amount described in the examples of Patent Documents 4 and 5 is an average value measured at several points, in the present embodiment, the maximum value is taken as the bending amount in the present embodiment. This is because in an electronic circuit in which a plurality of signals need to be synchronized, even a single deviation in the arrival time of the signals may lead to inconvenience in signal processing.

The sum of the yarn width of the warp and the yarn width of the weft in the glass cloth Q of the present embodiment is preferably 380 μm or more and 500 μm or less, preferably 380 μm or more and 480 μm or less, and more preferably 400 μm or more and 480 μm or less. ..
When the sum of the thread width of the warp and the thread width of the weft is 380 μm or more, the contact area between the warp and the weft becomes large at the intersection of the warp and the weft, the mutual binding force becomes strong, and the stitches bend. Is suppressed.
When the sum of the warp width and the weft width is 500 μm or less, the mutual binding force between the warp and the weft at the intersection of the warp and the weft does not become too strong, and the warp and the weft become appropriate. Since there is room for movement, in a thin glass cloth having a thickness of 16 μm or less, when stress is applied, the warp and weft move from the intersection point as a base point, so that the stress is relaxed and the generation and breakage of wrinkles are suppressed.

Further, since the line width generally used for a multilayer wiring board or the like is about 0.1 mm, a transmission line arranged so as to be parallel to the weft in a glass cloth having a weft occupancy of 75% or more and 90% or less. Since the thread width of the weft is preferably 300 μm or less in order to suppress the change in the abundance rate of the glass of the insulator layer through which the warp passes, the sum of the thread width of the warp and the thread width of the weft is 500 μm.
It is preferably m or less.
When the sum of the yarn width of the warp and the yarn width of the weft is 380 μm or more and 500 μm or less, a glass cloth having no wrinkles or bending and excellent handleability can be obtained.

In the glass cloth Q of the present embodiment, the sum of the yarn width of the warp and the yarn width of the weft is 380 μm or more 5
The sum of the elongation rate in the warp direction generated when a load of 5 N per 25 mm width is applied in the warp direction and the elongation rate in the warp direction generated when a load of 5 N per 25 mm width is applied in the weft direction is 00 μm or less. It is preferably 0.50% or less.

(Ratio of warp and weft at cross-sectional height)
In the glass cloth of the present embodiment, the ratio of the cross-sectional height in the warp direction to the cross-sectional height in the weft direction is 9.
It is preferably 0% or more and 110% or less.
The ratio of the cross-sectional height in the warp direction to the cross-sectional height in the weft direction is more preferably 92% or more 108.
% Or less, more preferably 95% or more and 105% or less.
The cross-sectional height in the warp direction is the cross-sectional height of the glass cloth when the cross-sectional image of the glass cloth is observed so that four or more adjacent warps are continuously inserted. Similarly, the cross-sectional height in the weft direction is the cross-sectional height of the glass cloth when the cross-sectional image of the glass cloth is observed so that four or more adjacent wefts are continuously inserted.
When the ratio of the cross-sectional height in the warp direction to the cross-sectional height in the weft direction is 90% or more and 110% or less, the glass and resin in the Z-axis direction, that is, in the thickness direction, at the portion where the glass thread in the insulator layer exists. Since the uniformity of presence with the composition is improved, the fluctuation of the signal propagation rate tends to be small.

In the glass cloth Q of the present embodiment, the sum of the yarn width of the warp and the yarn width of the weft is 380 μm or more 5
It is 00 μm or less, and the ratio of the cross-sectional height in the warp direction to the cross-sectional height in the weft direction is 90% or more 1
It is preferably 10% or less.

(Mass of glass thread)
The glass cloth of the present embodiment has a mass per unit length of warp 1.40 × 10 ^-6 kg.
It is more than / m and less than 1.80 × 10 ^-6 kg / m, and the mass per unit length of the warp is 1.8.
0 × 10 ^-6 kg / m or more and 4.00 × 10 ^-6 kg / m or less, and the ratio of the average mass per unit length of the warp to the average mass per unit length of the warp, that is, the weft The ratio of warp and weft (warp / warp ratio) is preferably 1.20 or more and 1.80 or less.
The ratio of the mass per unit length of the warp, the mass per unit length of the warp, and the above average mass is preferably the warp; 1.45 × 10 ^-6 kg / m or more 1.75 × 10- ^, respectively. ⁶ kg /
Less than m, weft; 1.90 × 10 ^-6 kg / m or more and 3.50 × 10 ^-6 kg / m or less, weft / warp ratio; 1.22 or more and 1.75 or less, and even more preferably, respectively. Warp; 1.5
0 x 10 ^-6 kg / m or more and 1.70 x 10 ^-6 kg / m or less, weft; 2.00 x 10 ^-6 kg / m
m or more and 3.00 × 10 ^-6 kg / m or less, weft / warp ratio; 1.23 or more and 1.70 or less.

In the manufacturing process, the glass cloth is physically loaded in the step of adjusting the coating amount of the silane agent after impregnating the silane treatment agent or in the fiber opening processing step. Further, even when the prepreg is applied using the glass cloth, a physical load is applied to the glass cloth in the process of adjusting the amount of the resin varnish and drying after the impregnation coating of the resin varnish. In order to stably and continuously convey the glass cloth without cutting it in the above step, it is preferable that the warp yarn has a certain strength or more, and therefore a glass yarn of 1.40 × 10 ^-6 kg / m or more is used. Is preferable. On the other hand, as a warp, the average weight per unit length is 1.80 × 10 ^-6 kg / m.
By using less than glass yarn, the thickness can be maintained at 16 μm or less, the weaving density can be increased to 90 or more, for example, and the occurrence of pinholes tends to be suppressed.

By using a glass yarn having an average mass of 1.80 × 10 ^-6 kg / m or more per unit length as the warp and weft, the rigidity of the warp and weft is increased and it tends to be easy to reduce the bending of the weft. It is preferable that the mass of the glass yarn used for the weft is large because it has excellent rigidity. However, in order to keep the thickness of the glass cloth to 16 μm or less, the average mass per unit length is 4.0.
It is preferably 0 × 10 ^-6 kg / m or less.

Further, when the mass ratio of the warp and the warp is 1.20 or more, the difference between the rigidity of the warp and the rigidity of the warp becomes large. The swell can be kept small, and the warp and weft intersecting with each other can be kept in close contact with each other with few gaps. In addition, the swelling state of the weft inserted without binding force varies depending on the variation in the line tension acting on the warp in the weaving process, but the difference in rigidity between the warp and the weft increases, so that the weft Fluctuations in the swell structure can be kept small. Therefore, the fluctuation of the "elongation amount in the initial deformation region" when the tensile tension acts is small, and there is a tendency to stably obtain a glass cloth having a small amount of bending.
Furthermore, as a result of the swell of the weft becoming smaller and the swell of the warp becoming larger, the crimp amplitude of the weft and the warp becomes closer, and the crimp amplitude of the warp becomes 50% or more and 80% of the thickness of the glass cloth.
Below, there is a tendency that the crimp amplitude of the warp and weft can be adjusted in the range of 60% or more and 90% or less of the glass cloth thickness.

On the other hand, when the mass ratio of the warp and the warp is 1.80 or less, the difference in rigidity between the warp and the warp is prevented from becoming extremely large, and the undulating structure of the warp is appropriately preserved with the warp. Since there is no large difference in the undulation structure from the weft, it tends to be possible to prevent the anisotropy of dimensional stability and warp when the printed wiring board is formed due to the difference in rigidity between the warp and the weft.
The mass per unit length of the warp, the mass per unit length of the warp, and the ratio of the mass of the warp to the warp are within the above range, so that the anisotropy of dimensional stability when the printed wiring board is used and While preventing warpage, there is a tendency that the "elongation amount in the initial deformation region" when tensile tension acts can be reduced to a specific range.

(Average filament diameter, average number of filaments)
In the glass cloth of the present embodiment, the average number of filaments of the warp and weft is substantially the same, the average filament diameter of the warp is 3.7 μm or more and 4.3 μm or less, and the average filament diameter of the warp is 4.2 μm or more and 5.3 μm or less, and the ratio of the average filament diameter of the weft to the average filament diameter of the warp (weft / warp ratio) is 1.07 or more and 1.30.
The following is preferable.

By keeping the average number of filaments and the average filament diameter of the warp and weft within the above range, the thickness of the glass cloth is maintained at 16 μm or less, and the anisotropy and warpage of the dimensional stability of the printed wiring board are prevented. It tends to increase the rigidity in the weft direction and suppress the bending of the eyes.
The average filament diameter of the warp and weft, and the range of the weft / warp ratio of the average filament diameter are more preferably 3.8 μm or more and 4.2 μm or less, and 4.3 μm, respectively.
Warp / weft ratio of 5.2 μm or less and average filament diameter; 1.08 or more and 1.25 or less, more preferably warp; 3.9 μm or more and 4.1 μm or less, weft; 4.4, respectively.
The weft / warp ratio of μm or more and 5.1 μm or less and the average filament diameter; 1.09 or more and 1.20 or less.

The fact that the average number of filaments of the warp and the weft is substantially the same means that the ratio (weft / warp ratio) between the number of filaments of the warp and the number of filaments of the weft is in the range of 0.94 or more and 1.06 or less. Point to. When the weft / warp ratio of the average number of filaments is 0.94 or more and 1.06 or less, the effect of increasing the filament diameter of the weft, that is, the rigidity in the weft direction tends to be excellent.
Further, in the present embodiment, when the average number of filaments of the warp and weft is substantially the same, the number of filaments of the warp and weft is preferably 60 or less. The number of filaments is 6
By setting the number to 0 or less, the filaments are easily diffused by physical processing in the glass cloth manufacturing process, and the filament distribution in the Z direction of the glass yarn bundle can be reduced, so that the thickness of the glass cloth can be easily reduced. In order to reduce the thickness of the glass cloth, it is preferable that the number of filaments is small, but from the viewpoint of the strength and handleability of the glass cloth, when the average number of filaments of the warp and weft is substantially the same, the lower limit of the number of filaments is The number is preferably 44 or more, more preferably 46 or more, still more preferably 48 or more.

In the glass cloth of the present embodiment, the average filament diameters of the warp and the weft are substantially the same, the average number of warps is 43 or more and 70 or less, and the average number of filaments of the warp is 55. The number is preferably 80 or less, and the ratio of the average number of filaments of the weft to the average number of filaments of the warp (weft / warp ratio) is more than 1.25 and preferably 1.50 or less.
By keeping the average number of filaments of the warp and weft and the average filament diameter within the above range, the thickness of the glass cloth is maintained at 16 μm or less, and the anisotropy and warpage of the dimensional stability of the printed wiring board are prevented. , The rigidity in the weft direction is increased, and the bending of the eyes tends to be suppressed.
The average number of warps and wefts, and the range of the ratio (weft / warp ratio) are more preferably warps; 43 or more and 65 or less, wefts; 57 or more and 75 or less, and the average number of filaments / wefts / Warp ratio: 1.27 or more and 1.45 or less, more preferably warp: 45 or more and 60 or less, weft: 60 or more and 70 or less, average filament weft / warp ratio: 1.30 or more 1 It is .40 or less.

The fact that the average filament diameters of the warp and weft are substantially the same means that the ratio (weft / warp ratio) between the filament diameter of the warp and the filament diameter of the weft is in the range of 0.95 or more and 1.05 or less. .. When the weft / warp ratio of the average filament diameter is in the range of 0.95 or more and 1.05 or less, the effect of increasing the number of filaments of the weft, that is, the rigidity in the weft direction tends to be excellent.
Further, in the present embodiment, when the average filament diameters of the warp and weft are substantially the same,
The filament diameter of the warp and weft is preferably 3.8 μm or more. When the average filament diameter of the warp and weft is 3.8 μm or more, the rigidity of the glass cloth tends to be increased. It is preferable that the filament diameter is large in order to increase the rigidity of the glass cloth, but from the viewpoint of the thickness of the glass cloth, when the average filament diameter of the warp and the weft is substantially the same, the average filament diameter of the warp and the weft The upper limit is preferably 4.4.
It is μm or less, more preferably 4.3 μm or less, still more preferably 4.2 μm or less.

The glass thread constituting the glass cloth of the present embodiment is not particularly limited, and E glass (non-alkali glass) generally used for printed wiring board applications may be used.
Alternatively, low dielectric constant glass such as D glass, L glass, NE glass and silica glass (Q glass), high strength glass such as S glass and T glass, and high dielectric constant glass such as H glass may be used. ..
By using glass fiber yarn with a dielectric constant close to that of the impregnated resin as the warp and weft,
There is a tendency that the non-uniformity of the dielectric constant can be further reduced. The permittivity of glass cloth is
From the viewpoint of reducing the non-uniformity of the dielectric constant, it is preferably 5.0 or less, more preferably 4.5 or less.

The woven structure of the glass cloth is not particularly limited, and examples thereof include woven structures such as plain weave, Nanako weave, satin weave, and twill weave. Further, a mixed weaving structure using different types of glass threads may be used. Of these, a plain weave structure is preferable.

Further, the glass cloth of the laminated board used for the printed wiring board or the like is usually subjected to surface treatment with a treatment liquid containing a silane coupling agent, but the silane coupling agent generally used as the silane coupling agent is silane coupling. Agents can be used, as needed, acids, dyes,
Pigments, surfactants and the like may be added.

As the silane coupling agent, for example, it is preferable to use the silane coupling agent represented by the formula (2).
X (R) _3-n SiY _n ... (2)
In formula (2), X is an organic functional group having at least one of an amino group and an unsaturated double-bonding group, Y is an independently alkoxy group, and n is 1 or more and 3 The following integers, R is a group independently selected from the group consisting of a methyl group, an ethyl group and a phenyl group.

X is preferably an organic functional group having at least 3 or more of an amino group and an unsaturated double bond group, and X is an organic having at least 4 or more of an amino group and an unsaturated double bond group. It is more preferably a functional group.
Although any form can be used as the above-mentioned alkoxy group, an alkoxy group having 5 or less carbon atoms is preferable from the viewpoint of stabilizing the glass cloth.

Specific examples of the silane coupling agent include N-β- (N-vinylbenzylaminoethyl) -γ-aminopropyltrimethoxysilane and its hydrochloride salt, N-β- (N-vinylbenzylaminoethyl)-. γ-Aminopropylmethyldimethoxysilane and its hydrochlorides,
N-β- (N-di (vinylbenzyl) aminoethyl) -γ-aminopropyltrimethoxysilane and its hydrochloride, N-β- (N-di (vinylbenzyl) aminoethyl) -N-γ-
(N-vinylbenzyl) -γ-aminopropyltrimethoxysilane and its hydrochloride, N-
β- (N-benzylaminoethyl) -γ-aminopropyltrimethoxysilane and its hydrochloride, N-β- (N-benzylaminoethyl) -γ-aminopropyltri ethoxysilane and its hydrochloride, γ-( 2-Aminoethyl) Aminopropyltrimethoxysilane, γ-
Examples thereof include known single substances such as (2-aminoethyl) aminopropyltriethoxysilane, aminopropyltrimethoxysilane, vinyltrimethoxysilane, metharoxypropyltrimethoxysilane, and acryloxypropyltrimethoxysilane, or mixtures thereof.

The molecular weight of the silane coupling agent is preferably 100 to 600, more preferably 150 to 500, and even more preferably 200 to 450. Among these, it is preferable to use two or more kinds of silane coupling agents having different molecular weights. By treating the surface of the glass yarn with two or more kinds of silane coupling agents having different molecular weights, the density of the treatment agent on the glass surface tends to be high, and the reactivity with the matrix resin tends to be further improved.

The ignition loss value of the glass cloth is preferably 0.10% by mass or more and 2.00% by mass or less, more preferably 0.12% by mass or more and 1.50% by mass or less, and further preferably 0.
.. It is 15% by mass or more and 1.20% by mass or less. The ignition loss value of glass cloth is an index for indirectly evaluating the amount of surface treatment of glass cloth with a silane coupling agent.
When the ignition loss value is 0.10% by mass or more, the silane coupling agent is uniformly surface-treated on the glass cloth, the texture of the glass cloth becomes hard, and it becomes difficult to bend the eyes, which is preferable.
When the ignited residual value is 2.00% or less, the texture of the glass cloth is kept moderately soft, so that wrinkles are less likely to occur, which is preferable. The ignition loss value of the glass cloth is a value obtained according to the method described in JIS R 3420.

<Manufacturing method of glass cloth>
The method for producing the glass cloth of the present embodiment is not particularly limited, but for example, the surface of the glass filament is almost completely covered with the silane coupling agent by a treatment liquid having a concentration of the silane coupling agent of 0.1 to 3.0 wt%. A method having a coating step of covering with glass, a fixing step of fixing the silane coupling agent to the surface of the glass filament by heat drying, and a fiber opening step of opening the glass thread of the glass cloth can be preferably mentioned.

As the solvent for dissolving or dispersing the silane coupling agent, either water or an organic solvent can be used, but from the viewpoint of safety and protection of the global environment, it is preferable to use water as the main solvent.
As a method of obtaining a treatment liquid using water as a main solvent, a method of directly adding a silane coupling agent to water, a method of dissolving the silane coupling agent in a water-soluble organic solvent to prepare an organic solvent solution, and then using the organic solvent solution. Any method of putting it in water is preferable. It is also possible to use a surfactant in combination in order to improve the water dispersibility and stability of the silane coupling agent in the treatment liquid.

As a method of applying the silane coupling agent treatment liquid to the glass cloth, (a) a method of collecting the treatment liquid in a bath and dipping and passing the glass cloth, (b) treatment with a roll coater, a die coater, a gravure coater or the like. Examples thereof include a method of directly applying the liquid to the glass cloth. When applying by the method (a) above, it is preferable to select the immersion time of the glass cloth in the treatment liquid to be 0.5 seconds or more and 1 minute or less.

Further, as a method of applying the silane coupling agent treatment liquid to the glass cloth and then heating and drying the solvent, known methods such as hot air and electromagnetic waves can be mentioned.
The heating and drying temperature is preferably 90 ° C. or higher, more preferably 100 ° C. or higher so that the reaction between the silane coupling agent and the glass can be sufficiently performed. Further, the heating and drying temperature is preferably 300 ° C. or lower, more preferably 200 ° C. or lower, in order to prevent deterioration of the organic functional group of the silane coupling agent.

The method for opening the fiber in the fiber opening step is not particularly limited, but for example, a glass cloth can be used.
Examples thereof include a method of opening the fiber with spray water (high pressure water opening), a vibro washer, ultrasonic water, a mangle, and the like. In order to keep the total area of the basket hole within a certain range, it is preferable to carry out the fiber opening step with spray water.
When opening the fiber with spray water, the water pressure may be appropriately set, and it is preferable that the water pressure is constant in order to adjust the total area of the basket holes existing in the glass cloth. Here, to make the water pressure constant means to reduce the difference between the water pressure of the spray set for carrying out the fiber opening and the maximum and minimum values of the actual water pressure. It may have a step of heating and drying before and after the fiber opening step.

<Prepreg>
One of the present embodiments is a prepreg composed of the glass cloth and the matrix resin described in the present embodiment. The prepreg of the present embodiment is a prepreg having a small thickness and little bending, and can be preferably used as a prepreg for a printed wiring board.
Here, the difference in dielectric constant between the glass cloth and the matrix resin is preferably 3.0 or less.
It is more preferably 2.0 or less, still more preferably 1.0 or less. The smaller the difference in dielectric constant, the more preferable, and the lower limit of the dielectric constant may be 0 or more. By reducing the difference in dielectric constant between the glass cloth and the cured resin, even if there is a variation between the abundance of glass and the abundance of resin in the insulator layer, the non-uniformity of the dielectric constant can be reduced. This tends to reduce fluctuations in the signal propagation speed.

The prepreg using the glass cloth of the present embodiment can be produced according to a conventional method. As a method for producing the prepreg of the present embodiment, for example, the glass cloth of the present embodiment is impregnated with a varnish obtained by diluting a matrix resin such as an epoxy resin with an organic solvent, and then the organic solvent is volatilized in a drying furnace. Then, the thermosetting resin is cured to a B stage state, that is, a semi-cured state to obtain a resin-impregnated prepreg.
As the matrix resin, in addition to the above-mentioned epoxy resin, heat-curing of bismaleimide resin, cyanate ester resin, unsaturated polyester resin, polyimide resin, bismaleimide triazine resin (also referred to as BT resin), functionalized polyphenylene ether resin and the like. Sex resin;
Examples thereof include polyphenylene ether resin, polyetherimide resin, liquid crystal polymer of all aromatic polyester (also referred to as LCP), thermoplastic resin such as polybutadiene and fluororesin; or a mixed resin thereof. From the viewpoint of improving the dielectric property, heat resistance, solvent resistance, and press moldability, the thermoplastic resin may be modified with a thermosetting resin.

In addition, the matrix resin is an inorganic filler such as silica or aluminum hydroxide in the resin.
A resin in which a flame retardant such as a bromine-based, phosphorus-based or metal hydroxide, a silane coupling agent, a heat stabilizer, an antistatic agent, an ultraviolet absorber, a pigment, a colorant, a lubricant and the like are mixed may be used.

<Printed wiring board>
One of the present embodiments is a printed wiring board composed of the glass cloth and the matrix resin of the present embodiment. The printed wiring board of the present embodiment can be a printed wiring board in which the deviation in the positional relationship between the glass thread and the transmission line is small in the printed wiring board and the signal propagation speed difference between the plurality of transmission lines is small.
Here, the difference in dielectric constant between the glass cloth and the matrix resin is preferably 3.0 or less.
It is more preferably 2.0 or less, still more preferably 1.0 or less. The smaller the difference in the dielectric constant, the more preferable, and the lower limit of the dielectric constant may be 0 or more. By reducing the difference in dielectric constant between the glass cloth and the cured resin, the non-uniformity of the dielectric constant is reduced even if the abundance of glass in the insulator layer and the abundance of the resin composition vary. Therefore, there is a tendency that fluctuations in the signal propagation speed can be reduced.

The printed wiring board of this embodiment can be manufactured according to a conventional method. For example, a single or a plurality of prepregs of the present embodiment are laminated, and copper foils are attached to both sides of the obtained laminated board.
A step of producing a hardened copper-clad laminate by heating and pressurizing, a step of forming a circuit pattern made of copper foil on both sides of the copper-clad laminate, and then forming a through hole between the circuit patterns on both sides. A double-sided printed wiring board can be manufactured through a process of ensuring an electrical connection.

Hereinafter, the present invention will be specifically described with reference to Examples.
The physical characteristics of the glass cloth in Examples and Comparative Examples were measured according to JIS R3420.
The elongation rate in the warp direction and the elongation rate in the weft direction of the glass cloth were measured according to a method according to JIS 3420.
The amount of bending of the glass cloth was measured according to the above-mentioned method in accordance with JIS L1096.

<Example 1>
The warp has an average filament diameter of 4.0 μm, the number of filaments is 50, the number of twists is 1.0Z, and the weight per unit length is 1.65 × 10 ^-6 kg / m. , 50 filaments, 1.0Z twist, 2.07 x weight per unit length
Using ^10-6 kg / m E-glass yarn, using an air jet room, 93.5 warps /
A glass cloth was woven with a weaving density of 25 mm and 70 wefts / 25 mm. The obtained glass cloth of the raw machine was heat-treated at 400 ° C. for 24 hours and deglued. Next, the glass cloth was immersed in a treatment liquid using N-β- (N-vinylbenzylaminoethyl) -γ-aminopropyltrimethoxysilane; SZ6032 (manufactured by Toray Dow Corning), which is a silane coupling agent. After squeezing, the mixture was dried at 120 ° C. for 1 minute, and further opened by high-pressure water spray to obtain a glass cloth A having a weight of 12.1 and a thickness of 13 μm.
The warp and weft widths of the glass cloth A are 139 μm and 285 μm, respectively, and the weft occupancy is 80%, the elongation in the warp direction is 0.20%, the elongation in the weft direction is 0.27%, and the cross section in the warp direction. The ratio of the height to the cross-sectional height in the warp direction was 0.97. The amount of bending of the glass cloth A was 3 mm, and the glass cloth was excellent in handleability.
The glass cloth A was processed to a width of 650 mm for a coating test, and prepreg coating was performed using an epoxy resin varnish. The epoxy resin varnish includes 80 parts by mass of a low-bromineed bisphenol A type epoxy resin, 20 parts by mass of a cresol novolak type epoxy resin, 2 parts by mass of dicyandiamide, 0.2 parts by mass of 2-ethyl-4-methylimidazole, and 2-methoxy. -Prepared by blending 100 parts by mass of ethanol. The glass cloth is conveyed at a speed of 3 m / min, the glass cloth A is immersed in the epoxy resin varnish, and the excess varnish is scraped off through a slit whose gap is adjusted so that the resin content is 68% by mass, and then the drying temperature is reached. The epoxy resin was dried under the conditions of 170 ° C. and a drying time of 1 minute and 30 seconds, and the epoxy resin was semi-cured (B-staged) to obtain prepreg A.
The prepreg A was cut into a size of 550 mm × 550 mm, and then copper foils having a thickness of 35 μm were placed on both surfaces of the prepreg A, and then compression molded at 175 ° C. and 40 kgf / cm ² to obtain a substrate A. The obtained substrate A was subjected to an etching treatment and processed so that a line of a copper foil having a width of 200 μm was arranged at a right angle to the warp to obtain an evaluation substrate A.
With reference to the position 2 cm from the end of the copper foil wire, the deviation between the copper foil wire and the weft is 0.
.. As a result of evaluating the distance within 5 times, it was 73 mm.

<Example 2>
Weaving of glass cloth and subsequent processing were performed by the same method as in Example 1 except that the weft density was 75 threads / 25 mm, and glass cloth B having a weight of 12.5 g / m ² and a thickness of 14 μm was obtained. Obtained. The thread widths of the warp and weft of the glass cloth B are 137 μm and 276, respectively.
It is μm, the weft occupancy is 83%, the elongation in the warp direction is 0.18%, and the elongation in the weft direction is 0.
At 24%, the ratio of the cross-sectional height in the warp direction to the cross-sectional height in the weft direction was 1.00. The amount of bending of the glass cloth B was 2 mm, and the glass cloth was excellent in handleability.
In the same manner as in Example 1, the evaluation substrate B was produced, and the deviation between the copper foil wire and the weft was 0.
As a result of evaluating the distance within 5 times, it was 101 mm.

<Example 3>
Weaving of glass cloth and subsequent processing were performed by the same method as in Example 1 except that the weft density was 78 threads / 25 mm to obtain a glass cloth C having a weight of 12.7 g / m ² and a thickness of 15 μm. Obtained. The thread widths of the warp and weft of the glass cloth C are 135 μm and 274, respectively.
It is μm, the weft occupancy is 85%, the elongation in the warp direction is 0.18%, and the elongation in the weft direction is 0.
22%, the ratio of the cross-sectional height in the warp direction to the cross-sectional height in the weft direction was 1.03. The amount of bending of the glass cloth C was 1 mm, and the glass cloth was excellent in handleability.
In the same manner as in Example 1, the evaluation substrate C was produced, and the deviation between the copper foil wire and the weft was 0.
As a result of evaluating the distance within 5 times, it was 198 mm.

<Example 4>
A glass yarn with an average filament diameter of 4.0 μm, 67 filaments, 1.0 Z twist, and a weight of 2.20 × 10 ^-6 kg / m per unit length is used for the weft, and the weft density is 68. A glass cloth was woven and subsequently processed by the same method as in Example 4 except that the thickness was set to / 25 mm, to obtain a glass cloth D having a weight of 12.4 g / m ² and a thickness of 13 μm. The warp and weft widths of the glass cloth D are 149 μm and 285 μm, respectively, and the weft occupancy is 78%, the elongation in the warp direction is 0.18%, the elongation in the weft direction is 0.26%, and the cross section in the warp direction. The ratio of the height to the cross-sectional height in the warp direction was 1.06. The amount of bending of the glass cloth D is 2
.. It was a glass cloth having a size of 5 mm and having excellent handleability.
In the same manner as in Example 1, the evaluation substrate D was produced, and the deviation between the copper foil wire and the weft was 0.
As a result of evaluating the distance within 5 times, it was 97 mm.

<Example 5>
Weaving of glass cloth and subsequent processing were performed by the same method as in Example 4 except that the weft density was 72 threads / 25 mm to obtain a glass cloth E having a weight of 12.8 g / m ² and a thickness of 14 μm. Obtained. The thread widths of the warp and weft of the glass cloth E are 148 μm and 281 respectively.
It is μm, the weft occupancy is 81%, the elongation in the warp direction is 0.19%, and the elongation in the weft direction is 0.
At 25%, the ratio of the cross-sectional height in the warp direction to the cross-sectional height in the weft direction was 1.03. The amount of bending of the glass cloth E was 2.0 mm, and the glass cloth was excellent in handleability.
In the same manner as in Example 1, the evaluation substrate E was produced, and the deviation between the copper foil wire and the weft was 0.
As a result of evaluating the distance within 5 times, it was 107 mm.

<Example 6>
Weaving of the glass cloth and the subsequent treatment were performed by the same method as in Example 4 except that the weft density was 75 threads / 25 mm, and the glass cloth F having a weight of 13.3 g / m ² and a thickness of 14 μm was obtained. Obtained. The thread widths of the warp and weft of the glass cloth F are 147 μm and 280, respectively.
It is μm, the weft occupancy is 84%, the elongation in the warp direction is 0.18%, and the elongation in the weft direction is 0.
23%, the ratio of the cross-sectional height in the warp direction to the cross-sectional height in the weft direction was 1.03. The amount of bending of the glass cloth F was 0.5 mm, and the glass cloth was excellent in handleability.
In the same manner as in Example 1, the evaluation substrate F was produced, and the deviation between the copper foil wire and the weft was 0.
As a result of evaluating the distance within 5 times, it was 412 mm.

<Example 7>
The warp has an average filament diameter of 4.0 μm, the number of filaments is 50, the number of twists is 1.0Z, and the weight per unit length is 1.46 × 10 ^-6 kg / m. , Number of filaments 50, Number of twists 1.0Z, Weight per unit length 1.95 ×
By the same method as in Example 1, except that the weaving density of the warp threads was 93.5 threads / 25 mm and the weft density of the weft threads was 72 threads / 25 mm using ^10-6 kg / m L glass threads. Weaving of glass cloth and subsequent processing are performed to make glass cloth G with a weight of 11.3 g / m ² and a thickness of 13 μm.
Got The warp and weft widths of the glass cloth G are 151 μm and 284 μm, respectively, and the weft occupancy is 82%, the elongation in the warp direction is 0.18%, and the elongation in the weft direction is 0.26%.
The ratio of the cross-sectional height in the warp direction to the cross-sectional height in the weft direction was 1.03. The amount of bending of the glass cloth G was 2.0 mm, and the glass cloth was excellent in handleability.
In the same manner as in Example 1, the evaluation substrate G was produced, and the deviation between the copper foil wire and the weft was 0.
As a result of evaluating the distance within 5 times, it was 104 mm.

<Comparative Example 1>
The average filament diameter of both warp and weft is 4.0 μm, the number of filaments is 50, and the number of twists is 1.
0Z, weight per unit length 1.65 x 10 ^-6 kg / m E glass yarn is used, and an air jet room is used to make a glass cloth with a weaving density of 93.5 yarns / 25 mm for both warp and weft. Weaved. The obtained glass cloth of the raw machine was heat-treated at 400 ° C. for 24 hours and deglued. Next, N-β- (N-vinylbenzylaminoethyl) -γ-, which is a silane coupling agent, is used.
Aminopropyltrimethoxysilane; glass cloth was dipped in a treatment solution using SZ6032 (manufactured by Toray Dow Corning), squeezed, dried at 120 ° C. for 1 minute, and further opened by high-pressure water spray. A glass cloth I having a weight of 12.5 and a thickness of 14 μm was obtained.
The warp and weft widths of the glass cloth I are 132 μm and 222 μm, respectively, and the weft occupancy is 83%, the elongation in the warp direction is 0.18%, the elongation in the weft direction is 0.36%, and the cross section in the warp direction. The ratio of the height to the cross-sectional height in the warp direction was 1.14. The amount of bending of the glass cloth I was 6 mm, and the glass cloth had a large bending.
In the same manner as in Example 1, the evaluation substrate I was produced, and the deviation between the copper foil wire and the weft was 0.
As a result of evaluating the distance within 5 times, it was 29 mm.

<Comparative Example 2>
Average filament diameter 4.0 μm for warps, 40 filaments, 1.0 Z twists, 1.32 x 10 ^-6 kg / m weight per unit length E-glass yarn, average filament diameter 4.0 μm for warp , Number of filaments 50, Number of twists 1.0Z, Weight per unit length 1.65 ×
A glass cloth was woven using an E-glass yarn of ^10-6 kg / m and an air jet room with a weaving density of 95 yarns / 25 mm for both warp and weft. 4 on the glass cloth of the obtained raw machine
It was heat-treated at 00 ° C. for 24 hours and deglued. Next, N-β-, which is a silane coupling agent,
(N-vinylbenzylaminoethyl) -γ-aminopropyltrimethoxysilane; SZ6
After immersing the glass cloth in the treatment liquid using 032 (manufactured by Toray Dow Corning) and squeezing the liquid,
Dry at 120 ° C. for 1 minute, then open the fibers with a high-pressure water spray, and weigh 10.4 g / m.
^2. A glass cloth J having a thickness of 14 μm was obtained.
The warp and weft widths of the glass cloth J are 123 μm and 213 μm, respectively, and the weft occupancy is 81%, the elongation in the warp direction is 0.28%, the elongation in the weft direction is 0.36%, and the cross section in the warp direction. The ratio of the height to the cross-sectional height in the warp direction was 0.97. The amount of bending of the glass cloth J was 8 mm, and the glass cloth had a large bending.
In the same manner as in Example 1, the evaluation substrate J was produced, and the deviation between the copper foil wire and the weft was 0.
As a result of evaluating the distance within 5 times, it was 16 mm.

<Comparative Example 3>
The average filament diameter of both warp and weft is 4.0 μm, the number of filaments is 50, and the number of twists is 1.
Glass cloth was woven with a weaving density of 85 yarns / 25 mm for both warp and weft using an E glass yarn of 0Z and a weight of 1.65 × 10 ^-6 kg / m per unit length using an air jet room. .. The glass cloth of the obtained raw machine was subjected to a fiber opening process (processing pressure 196 N / cm ² ) by a high-pressure sprinkling flow under a tension of 4.9 N / m. Then, it was heat-treated at 400 ° C. for 24 hours to remove the glue. Subsequently, a glass cloth was added to a treatment liquid using N-β- (N-vinylbenzylaminoethyl) -γ-aminopropyltrimethoxysilane; SZ6032 (manufactured by Toray Dow Corning), which is a silane coupling agent. After soaking and squeezing, dry at 120 ° C. for 1 minute and weigh 11
.. A glass cloth K having a thickness of 0 g / m ² and a thickness of 12 μm was obtained. The chemical and physical treatment of the glass cloth was based on the method of Example 2 of Patent Document 4: Japanese Patent No. 3756066.
The warp and weft widths of the glass cloth K are 184 μm and 200 μm, respectively, and the weft occupancy is 68%, the elongation in the warp direction is 0.26%, the elongation in the weft direction is 0.37%, and the cross-sectional height in the warp direction. The ratio of the cross-sectional height in the warp and weft direction was 1.06. The amount of bending of the glass cloth K was 7 mm, and the glass cloth had a large bending.
In the same manner as in Example 1, the evaluation substrate K was produced, and the deviation between the copper foil wire and the weft was 0.
As a result of evaluating the distance within 5 times, it was 21 mm.

<Comparative Example 4>
The average filament diameter of both warp and weft is 4.0 μm, the number of filaments is 40, and the number of twists is 1.
0Z, weight per unit length 1.32 x 10 ^-6 kg / m E glass yarn is used, and an air jet room is used to make a glass cloth with a weaving density of 94.5 yarns / 25 mm for both warp and weft. Weaved. The glass cloth of the obtained raw machine was subjected to a fiber opening process (processing pressure 196 N / cm ² ) by a high-pressure sprinkling flow under a tension of 4.9 N / m. Then, it was heat-treated at 400 ° C. for 24 hours to remove the glue. Subsequently, a glass cloth was immersed in a treatment liquid using SZ6032 (manufactured by Toray Dow Corning), which is a silane coupling agent, squeezed, dried at 120 ° C. for 1 minute, and weighed 10
.. 2. A glass cloth L having a thickness of 11 μm was obtained. The chemical and physical treatment of the glass cloth was based on the method of Example 2 of Patent Document 4: Japanese Patent No. 3756066.
The warp and weft widths of the glass cloth L are 156 μm and 175 μm, respectively, and the weft occupancy is 66%, the elongation in the warp direction is 0.16%, the elongation in the weft direction is 0.23%, and the cross section in the warp direction. The ratio of the height to the cross-sectional height in the warp direction was 1.09. The amount of bending of the glass cloth L was 7 mm, and the glass cloth had a large bending.
In the same manner as in Example 1, the evaluation substrate L was produced, and the deviation between the copper foil wire and the weft was 0.
As a result of evaluating the distance within 5 times, it was 15 mm.

<Comparative Example 5>
The weft is made of E-glass yarn with an average filament diameter of 4.5 μm, 50 filaments, 1.0 Z twist, and a weight of 2.07 × 10 ^-6 kg / m per unit length. 6
A glass cloth was woven and then processed by the same method as in Comparative Example 1 except that the number was 0/25 mm to obtain a glass cloth M having a weight of 11.4 g / m ² and a thickness of 12 μm.
The warp and weft widths of the glass cloth M are 134 μm and 267 μm, respectively, and the weft occupancy is 64%, the elongation in the warp direction is 0.21%, the elongation in the weft direction is 0.30%, and the cross section in the warp direction. The ratio of the height to the cross-sectional height in the warp direction was 1.09. The amount of bending of the glass cloth M was 5 mm, and the glass cloth had a large bending.
In the same manner as in Example 1, the evaluation substrate M was produced, and the deviation between the copper foil wire and the weft was 0.
As a result of evaluating the distance within 5 times, it was 41 mm.

Table 1 shows the characteristics and evaluation results of the glass cloth and the substrate produced in Examples and Comparative Examples.

The glass cloth of the present invention has industrial applicability as a base material used for a printed wiring board used in the electronic and electrical fields.

a: Warp and weft thread width b: Warp and weft spacing

Claims (18)

A glass cloth having a thickness of 8 μm or more and 16 μm or less, which is made by weaving a glass thread composed of a plurality of glass filaments as a warp and a weft.
Equation (1);
Y = F / (25000 / G) x 100 ... (1)
(In the formula, F is the thread width (μm) of the weft, and G is the weft density (book / 25 mm) of the weft.)
The abundance ratio Y of the warp and weft in the longitudinal direction, which is obtained in the above, is 75% or more and 90% or less.
A glass cloth in which the sum of the yarn width of the warp and the yarn width of the weft is 380 μm or more and 500 μm or less. The elongation rate in the warp direction generated when a load of 5 N per 25 mm width is applied in the warp direction, and the width 2
The sum with the elongation rate in the warp and weft direction generated when a load of 5N per 5 mm is applied in the warp and weft direction is 0.
The glass cloth according to claim 1, which is 50% or less. A glass cloth having a thickness of 8 μm or more and 16 μm or less, which is made by weaving a glass thread composed of a plurality of glass filaments as a warp and a weft.
Equation (1);
Y = F / (25000 / G) x 100 ... (1)
(In the formula, F is the thread width (μm) of the weft, and G is the weft density (book / 25 mm) of the weft.)
The abundance ratio Y of the warp and weft in the longitudinal direction, which is obtained in the above, is 75% or more and 90% or less.
A glass cloth in which the amount of warp bending is equal to or less than a value obtained by dividing a value of 10 times the weft spacing (mm) by 500 mm. The glass cloth according to claim 3, wherein the amount of warp bending is equal to or less than a value obtained by dividing a value of 5 times the weft spacing (mm) by 500 mm. The glass cloth according to claim 3, wherein the amount of warp bending is equal to or less than a value obtained by dividing a value 2.5 times the weft spacing (mm) by 500 mm. The glass cloth according to claim 3, wherein the amount of warp bending is equal to or less than a value obtained by dividing a value of 1.0 times the weft spacing (mm) by 500 mm. Claim 3 to the sum of the yarn width of the warp and the yarn width of the warp is 380 μm or more and 500 μm or less.
The glass cloth according to any one of 6. The elongation rate in the warp direction generated when a load of 5 N per 25 mm width is applied in the warp direction, and the width 2
The sum with the elongation rate in the warp and weft direction generated when a load of 5N per 5 mm is applied in the warp and weft direction is 0.
The glass cloth according to claim 7, which is 50% or less. The ratio of the cross-sectional height in the warp direction to the cross-sectional height in the weft direction is 90% or more and 110% or less.
The glass cloth according to claim 1 or 2. The sum of the yarn width of the warp and the yarn width of the warp is 380 μm or more and 500 μm or less.
The ratio of the cross-sectional height in the warp direction to the cross-sectional height in the weft direction is 90% or more and 110% or less.
The glass cloth according to any one of claims 3 to 6. The average mass per unit length of the warp is 1.4 x 10 ^-6 kg / m or more 1.8 x 10 ^-6 kg
Less than / m
The average mass per unit length of the weft is 1.8 x 10 ^-6 kg / m or more 4.0 x 10 ^-6 kg
/ M or less and
Any one of claims 1 to 10, wherein the ratio of the average mass per unit length of the warp (weft / warp ratio) to the average mass per unit length of the warp is greater than 1.20 and 1.80 or less. The glass cloth described in the section. The average number of filaments of the warp and weft is substantially the same, and
The average filament diameter of the warp is 3.7 μm or more and 4.3 μm or less.
The average filament diameter of the weft is 4.2 μm or more and 5.3 μm or less.
The glass cloth according to any one of claims 1 to 10, wherein the ratio of the average filament diameter of the weft to the average filament diameter of the warp (weft / warp ratio) is 1.07 or more and 1.40 or less. The average filament diameters of the warp and weft are substantially the same, and
The average number of warp filaments is 45 or more and 70 or less.
The average number of filaments of the weft is 55 or more and 80 or less.
The glass cloth according to any one of claims 1 to 10, wherein the ratio of the average number of filaments of the weft to the average number of filaments of the warp (weft / warp ratio) is larger than 1.25 and 1.50 or less. A prepreg composed of the glass cloth according to any one of claims 1 to 13 and a matrix resin. The prepreg according to claim 14, wherein the difference between the dielectric constant of the glass constituting the glass cloth at 10 GHz and the dielectric constant of the cured product of the matrix resin at 10 GHz is 3 or less. The prepreg according to claim 14, wherein the difference between the dielectric constant of the glass constituting the glass cloth at 10 GHz and the dielectric constant of the cured product of the matrix resin at 10 GHz is 2 or less. The prepreg according to claim 14, wherein the difference between the dielectric constant of the glass constituting the glass cloth at 10 GHz and the dielectric constant of the cured product of the matrix resin at 10 GHz is 1 or less. A printed wiring board produced by using the prepreg according to any one of claims 14 to 17.

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