JP7305467B2 - Long glass cloth rolls, prepregs, and printed wiring boards - Google Patents

Description

TECHNICAL FIELD The present invention relates to a roll-shaped long glass cloth, a prepreg, and a printed wiring board.

Printed wiring boards used in electronic devices are usually made by impregnating a base material such as glass cloth with a thermosetting resin such as epoxy resin or polyphenylene ether resin and drying to form a prepreg. It is manufactured by a method of laminating copper foils as necessary, heat-pressing to form a laminate, and then forming a circuit pattern made of copper foils.
2. Description of the Related Art In recent years, as information terminals such as smartphones have improved performance and high-speed communication, printed wiring boards have been remarkably reduced in dielectric constant and dielectric loss tangent. Many low-dielectric glass cloths have also been proposed for glass cloths constituting printed wiring boards (for example, Patent Documents 1 to 6).
The low dielectric glass cloth disclosed _{in Patent} Documents 1 to 6 has a low dielectric constant, Realizes low dielectric loss tangent.

Japanese Patent No. 4269194 JP 2010-508226 A International Publication No. 2016/175248 US9556060 publication International Publication No. 2017/187471 TWI1591041 publication

However, when the content of B ₂ O ₃ in the glass is increased in order to lower the dielectric of the glass cloth, the elastic modulus of the glass tends to decrease and the texture of the glass cloth tends to become soft. While the elastic modulus of E glass cloth is about 74 GPa, for example, the elastic modulus of NE glass cloth manufactured by Nitto Boseki Co., Ltd. is 64 GPa (published on the website of Nitto Boseki Co., Ltd.), L glass cloth manufactured by Asahi Kasei Co., Ltd. The elastic modulus determined by the pulse-echo overlap method is 61 GPa, and each of these low-dielectric glass cloths has a smaller elastic modulus than the E-glass cloth.

Here, a glass cloth with a small elastic modulus is likely to cause distortion of the woven structure such as slack, weave, and wrinkles in the surface treatment process, the fiber opening process, the conveying process, and the winding process during glass cloth production. Poor roll quality. Further, the glass cloth having a small elastic modulus has a problem that the dimensional variation becomes large at the time of heat and pressure molding in the process of manufacturing a printed wiring board and at the time of forming a circuit pattern.

The present invention has been made in view of the above problems, and even if the glass cloth has a small elastic modulus, the distortion of the woven structure such as wrinkles is suppressed (that is, the roll quality is excellent). To provide a glass cloth with small variation in dimensional change when it is pressed.

As a result of intensive studies by the present inventors in order to solve the above problems, the glass cloth wound on the winding core tube that satisfies the specific requirements has excellent roll quality, and dimensional change when used as a printed wiring board. The present inventors have found that the variation in the ratio can be suppressed to a small level, leading to the completion of the present invention.

That is, the present invention is as follows.
[1]
A roll-shaped long glass cloth composed of glass yarns composed of a plurality of glass filaments as warps and wefts and wound around a winding core tube,
1) The thickness of the glass cloth is 8 μm or more and 100 μm or less,
2) the winding hardness is 45 or more and 70 or less;
3) The width insertion amount is minus 0.5% or more and less than 0.1%,
Rolled long glass cloth that satisfies
[2]
The elastic modulus of the glass cloth is 50 GPa or more and 70 GPa or less.
The roll-shaped long glass cloth according to [1].
[3]
The elastic modulus of the glass cloth is 50 GPa or more and 63 GPa or less.
The roll-shaped long glass cloth according to [1].
[4]
The sum of the boron content and the phosphorus content is 5% by mass or more and 20% by mass or less,
The roll-shaped long glass cloth according to any one of [1] to [3].
[5]
The sum of the boron content and the phosphorus content is 6.5% by mass or more and 20% by mass or less,
The roll-shaped long glass cloth according to any one of [1] to [3].
[6]
The thickness of the glass cloth is 35 μm or more and 60 μm or less,
The winding hardness is 45 or more and 60 or less,
The roll-shaped long glass cloth according to any one of [1] to [5].
[7]
The glass cloth has a thickness of 8 μm or more and less than 35 μm,
The winding hardness is 50 or more and 65 or less,
The roll-shaped long glass cloth according to any one of [1] to [5].
[8]
A measurement point 80 mm inside from one end in the width direction, and measurements provided every 200 mm in a range from the measurement point toward the other end to 80 mm inside from the other end The coefficient of variation of the winding hardness calculated from each winding hardness measured at the point is 0.025 or less.
The roll-shaped long glass cloth according to any one of [1] to [7].
[9]
The difference in the winding hardness of the adjacent measurement points is less than 2,
The roll-shaped long glass cloth according to [8].
[10]
A roll-shaped long glass cloth according to any one of [1] to [9];
a matrix resin composition;
prepreg.
[11]
A printed wiring board comprising the prepreg according to [10].

According to the present invention, even when the elastic modulus of the glass cloth is small, the distortion of the woven structure such as wrinkles is suppressed, and the roll quality is excellent. can do.

FIG. 2 is a diagram schematically showing an example of an apparatus used for winding the glass cloth in manufacturing the roll-shaped long glass cloth of the present embodiment.

Hereinafter, an embodiment of the present invention (hereinafter referred to as "this embodiment") will be described in detail, but the present invention is not limited to this, and various modifications are possible without departing from the gist thereof. is.

<Rolled long glass cloth>
The glass cloth of the present embodiment is a roll-shaped long glass cloth which is composed of glass yarns made of a plurality of glass filaments as warps and wefts and wound around a winding core tube. A roll-shaped long glass cloth is also called a glass cloth roll.
Further, the roll-shaped long glass cloth of the present embodiment is
1) The thickness of the glass cloth is 8 μm or more and 100 μm or less,
2) the winding hardness is 45 or more and 70 or less;
3) The width insertion amount is minus 0.5% or more and less than 0.1%,
It is a roll-shaped long glass cloth that satisfies
The roll-shaped long glass cloth of the present embodiment is excellent in roll quality without distortion of the woven structure such as wrinkles that occurs during winding, and is used in the process of manufacturing a printed wiring board by using the glass cloth of the glass cloth roll. Variation in dimensional change can be reduced. This is because the glass cloth roll satisfies the above requirements 1) to 3), thereby reducing the distortion that occurred before it was formed into a roll shape, and also suppressing the generation of distortion during unrolling. It is considered to be

The thickness of the roll-shaped long glass cloth of the present embodiment is 8 μm or more and 100 μm or less, preferably 8 μm or more and 70 μm or less, more preferably 8 μm or more and 50 μm or less.
The thickness of the glass cloth must be reduced to 100 μm or less in order to reduce the thickness and increase the density of the printed wiring board due to the high functionality of digital equipment and the reduction in size and weight.
From the viewpoint of thinning and increasing the density of the printed wiring board, a thinner thickness is preferable, but the lower limit of the thickness is 8 μm from the viewpoint of strength.
The thickness of the roll-shaped long glass cloth in the present embodiment refers to the thickness of the glass cloth that constitutes the layer of the roll.

The width reduction amount in the roll-shaped long glass cloth of the present embodiment is minus 0.5% or more and less than 0.1%. The amount of marginalization is preferably minus 0.4% or more and less than 0.1%, more preferably minus 0.3% or more and 0.05% or less, and still more preferably minus 0.2% or more and 0.05%. % or less, and more preferably minus 0.1% or more and 0% or less.
Wiring of glass cloth is a phenomenon in which compressive stress acts in the width direction in the process of winding the glass cloth around the winding core tube because the warp is stretched by the winding tension and the weft shrinks due to the effect of this tension. .

Here, the "width insertion amount" in the present embodiment is defined by the following formula (1) using the width W _o of the glass cloth under no tension and the width W _a of the glass cloth on the take-up roll. This is the desired value.
Width insertion amount (%) = (W _a - W _o )/W _o x 100 (1)

The amount of widening can be specifically measured by the method described in the Examples.

The weft yarn is kept in its original waviness state or in a moderately stretched state, and the warp yarn is also restrained by the weft yarn, so that the waviness state becomes more uniform in the width direction. Therefore, a glass cloth having excellent dimensional stability can be obtained.
In addition, since the warp width is minus 0.5% or more, the waviness of the warp yarns does not increase excessively and is maintained in a form close to the original waviness state, so that the glass cloth can be laminated densely. and the winding state tends to be tight.
When the width reduction amount is minus 0.5% or more and less than 0.1%, the waviness structure of the warp and the weft of the glass cloth becomes uniform, and the winding state becomes a tightly laminated state.

In addition, since the width addition amount is minus 0.5% or more and less than 0.1%, it is generated in the glass cloth in the process before the winding of the glass cloth, such as the weaving process, the opening process, the surface treatment process, etc. Since even the distortion is eliminated, a glass cloth having a uniform woven structure can be obtained.
A glass cloth having a uniform woven structure and a wavy structure is obtained by impregnating the glass cloth with a thermosetting resin, drying it to form a prepreg, forming a laminate using the prepreg, and then forming a circuit pattern made of copper foil. WHEREIN: The dispersion|variation in a dimensional change can be reduced.

As a method for setting the width of the roll-shaped long glass cloth to minus 0.5% or more and less than 0.1%, for example, a method of adjusting the winding method in the step of winding the glass cloth around the winding core tube. (Specifically, a method of adjusting the winding tension, a method of adjusting the nip pressure, a method of spreading the glass cloth with an expander roll or the like immediately before winding, a rubber-like elastic body having rubber elasticity of the nip roll, etc. method, etc.), a method of adjusting the waviness structure and SS characteristics of the warp and weft by adjusting the yarn type, weave density, yarn width, etc. used for the glass cloth, the type and application of the silane coupling agent applied to the glass cloth A method of adjusting the friction coefficient of the glass cloth by adjusting the amount, a method of adjusting the texture of the glass cloth, a method of appropriately combining these methods, and the like can be mentioned.

It is preferable that the width insertion amount in the roll-shaped long glass cloth of the present embodiment is the same from the inner layer to the outer layer of the roll, that is, over the entire roll from the start to the end of the roll. The difference between the width insertion amount on the inner layer side and the width insertion amount on the outer layer side is preferably 0.2% or less, more preferably 0.1% or less, and still more preferably 0.05% or less. . Ideally, the lower limit of the difference in width-enhancement amount is 0%, but it may exceed 0%.
Here, the inner layer of the roll refers to the inner layer from half the thickness of the roll-shaped long glass cloth layer, and the outer layer of the roll refers to the outermost layer from half the thickness of the roll-shaped long glass cloth layer. until More specifically, for example, when the diameter of the winding core tube is 100 mm and the diameter of the entire roll including the diameter of the core tube is 300 mm, the inner layer is more than 100 mm and 200 mm or less, and the outer layer is more than 200 mm and 300 mm or less. is.

The method for measuring the difference in the width insertion amount between the inner layer side and the outer layer side of the roll-shaped long glass cloth is a method according to the following 1) to 6).
1) Measure the length in the width direction of the outermost surface of the glass cloth roll. At this time, the length W _a in the width direction perpendicular to the longitudinal direction (also referred to as the MD direction) is measured, and one end of the measured portion is marked.
2) When about 2 m of glass cloth is unwound from the glass cloth roll, the length W _o in the width direction of the marked points in 1) above is measured with no slack.
3) Obtain the width adjustment amount from the formula (1).
4) Using the same glass cloth roll, the above measurements 1) to 3) are repeated 5 times, and the average value is used as the width insertion amount on the outer layer side.
5) Next, the glass cloth roll is unrolled to a position of 1/4 of the thickness of the layer of the first glass cloth roll, and the length in the width direction at that point is measured. The above 1) to 4) are performed in the same manner to determine the width insertion amount on the inner layer side.
6) A difference between the inner layer side width insertion amount and the outer layer side width insertion amount is obtained from the width width insertion amount on the outer layer side and the width width insertion amount on the inner layer side.

In the winding of glass cloth, in order to prevent the tensile stress acting in the tangential direction inside the roll, that is, inside the outermost layer of the roll, from becoming negative, the roll diameter at the beginning of winding is made larger than when the roll diameter is small. It is common to reduce the winding tension as the thickness increases. As a result, the amount of widening differs between the inner layer side and the outer layer side of the roll, and the waviness of the warp and weft tends to differ between the inner layer side and the outer layer side of the roll.
In particular, glass cloth with a small elastic modulus and a soft texture is prone to wrinkles and other distortions due to the negative tensile stress acting inside the roll, so it is necessary to increase the difference in winding tension according to the roll diameter. , the difference in width insertion amount between the inner layer portion and the outer layer portion of the roll tends to be larger.
However, if there is a difference in the waviness of the warp and weft between the inner layer of the roll and the outer layer of the roll, the dimensional stability effect of the glass cloth will not be seen in the printed wiring board produced from the inner layer of the roll and the printed wiring board produced from the outer layer of the roll. different. That is, printed wiring boards produced from the same roll of glass cloth have large variations in dimensional change.
According to the roll-shaped long glass cloth of the present embodiment, the width insertion amount is the same from the inner layer to the outer layer of the roll, and the undulation structure of the inner layer portion and the outer layer portion of the roll can be made uniform. Therefore, it is possible to reduce variations in dimensional changes of printed wiring boards produced from the same roll.

The rolled long glass cloth of the present embodiment has a winding hardness of 45 or more and 70 or less, preferably 46 or more and 65 or less, more preferably 47 or more and 64 or less, and even more preferably 48 or more and 63 or less.
The winding hardness in this embodiment is measured by a SCHMIDT control instruments HP-10 type hardness tester manufactured by Hands Schmidt & Co GmbH Schichtstr. It is the average value of the winding hardness obtained by measuring one point at the center point in the width direction. Further, the winding hardness in the present embodiment is a value measured on the surface of the outermost layer.
When the winding hardness is 45 or more, the glass cloth is densely laminated when wound on the winding core tube, 1) compressive stress in the radial direction sufficiently acts on the outer layer side of the roll, and 2) tangential line. The same tensile stress acts on all layers in the direction. Also, the generation of strain can be suppressed in the general tensile tension range. In addition, it is presumed that the reason for the above 3) is that the layers of the glass cloth are mutually constrained and the glass cloth does not move inside the roll.
For the reasons 1) to 3) above, a glass cloth having a uniform woven structure can be obtained during prepreg coating.
When the winding hardness is 70 or less, the difference in tensile stress acting in the tangential direction between the inner layer portion and the outer layer portion of the roll can be kept small, and a glass cloth having excellent uniformity over the entire length of the roll-shaped long glass cloth can be obtained. be done.
Winding hardness can be measured by adjusting the winding tension, adjusting the nip pressure, or expanding the glass cloth with an expander roll or the like just before winding in the process of winding the glass cloth. It can be adjusted to 45 or more and 70 or less by winding up.

Further, the roll-shaped long glass cloth of the present embodiment preferably has a glass cloth thickness of 8 μm or more and less than 35 μm and a winding hardness of 50 or more and 65 or less.
When the thickness of the glass cloth is 8 µm or more and less than 35 µm, the winding hardness is more preferably 51 or more and 64 or less, and still more preferably 52 or more and 63 or less.
A thin glass cloth with a thickness of 8 μm or more and less than 35 μm tends to have a softer texture than a glass cloth with a thick thickness, and the woven structure is distorted due to stress relaxation when the cloth is wound in a roll. Cheap.
When the winding hardness is 50 or more, the interlaminar pressure in the state of being wound into a roll is high, and it is presumed that the glass loss layers are bound to each other, but the occurrence of distortion can be suppressed.

Further, the roll-shaped long glass cloth of the present embodiment preferably has a glass cloth thickness of 35 μm or more and 60 μm or less and a winding hardness of 45 or more and 60 or less.
When the thickness of the glass cloth is 35 μm or more and 60 μm or less, the winding hardness is more preferably 46 or more and 59 or less, and still more preferably 47 or more and 58 or less.
A glass cloth with a thickness of 35 μm or more and 60 μm or less tends to have a coarser winding density than a thin glass cloth with a thickness of 8 μm or more and less than 35 μm, so that distortion due to tight winding is likely to occur in the inner layer of the roll.
When the winding hardness is 60 or less, the internal stress acting in the tangential direction can be maintained on the tensile side even in the inner layer of the roll, so that a uniform glass cloth can be obtained without distortion caused by tight winding.

Further, the ignition loss of the roll-shaped long glass cloth of the present embodiment is preferably 0.1% by mass or more and 2.0% by mass or less, more preferably 0.13% by mass or more and 1.5% by mass or less, and further It is preferably 0.15 mass % or more and 1.3 mass % or less, and more preferably 0.16 mass % or more and 1.2 mass % or less.
The ignition loss of the glass cloth is an index for indirectly determining the amount of the coating layer containing the silane coupling agent applied to the surface of the glass cloth. The term "loss on ignition" as used herein is a value measured according to the method described in JISR3420.

When the ignition loss is 0.1% or more, sufficient adhesiveness to the matrix resin can be obtained when producing a laminate, and moisture absorption resistance and heat resistance tend to be further improved.
In addition, since the ignition loss is 0.1% or more, the frictional force between the glass cloths is reduced, and the glass cloth layers laminated in the winding roll are easy to move, so the woven structure is obtained when the glass cloth is wound. distortion tends to be corrected and uniform.
When the ignition loss is 2.0% by mass or less, the resin tends to penetrate well into the glass cloth. In addition, since the ignition loss is 2.0% by mass or less, the frictional force between the glass cloths can be suppressed to an appropriate level of slipperiness, and the glass cloth shrinks in the width direction on the winding roll and wrinkles, etc. distortion tends to be suppressed.

The roll-shaped elongated glass cloth of the present embodiment is preferably a low-dielectric glass cloth that can meet the demand for high-speed signals and has a smaller elastic modulus than E-glass.
Glass cloth of low dielectric glass includes, for example, L glass cloth (specific elastic modulus 61 GPa), NE glass cloth (elastic modulus 64 GPa), B ₂ O ₃ content 15% to 30% by mass, SiO ₂ content 45% by mass. % to 60 mass % and a P ₂ O ₅ content of 2 mass % to 8 mass % (elastic modulus 56 GPa).

The elastic modulus of the roll-shaped long glass cloth of the present embodiment is preferably 50 GPa or more and 70 GPa or less, more preferably 51 GPa or more and 65 GPa or less, still more preferably 52 GPa or more and 63 GPa, and even more preferably 54 GPa or more and 60 GPa or less.
The glass cloth of the low dielectric glass described above has a smaller elastic modulus than the E glass cloth and is easily affected by external stress. tends to be corrected and uniform.
In addition, the above-mentioned glass cloth, which has a low dielectric constant and a small elastic modulus, has a soft texture and is prone to sag, bending, wrinkles, and other distortions in the woven structure. Since the risk of impairing the performance, reliability, and safety is high, it is very useful to eliminate the distortion of the woven structure as the roll-shaped long glass cloth of this embodiment.

In the roll-shaped long glass cloth of the present embodiment, the sum of the boron content and the phosphorus content in the glass is preferably 5% by mass or more and 20% by mass or less, more preferably 6% by mass or more and 20% by mass. , more preferably 6.5% by mass or more and 20% by mass or less, and even more preferably 7% by mass or more and 10% by mass or less. The content of boron and the content of phosphorus are ratios (% by mass) to the total amount of glass constituting the roll-shaped long glass cloth.
There is a tendency that the larger the sum of the boron content and the phosphorus content in the glass, the smaller the dielectric constant and dielectric loss tangent of the glass cloth.
Since the sum of the boron content and the phosphorus content is 5% by mass or more, the dielectric constant and the dielectric loss tangent are significantly reduced compared to a laminate obtained using a general E-glass cloth. Applicability to large-capacity and high-speed data communication and signal processing is improved. For example, while the dielectric constant of E glass is about 7, when the sum of the boron content and the phosphorus content is 7.4%, the dielectric constant is about 4.8, and the boron content and the phosphorus content is 9.2%, the dielectric constant is about 4.4, which tends to be small.

The sum of the boron content and the phosphorus content is 20% by mass or less, so that the hygroscopic resistance and/or heat resistance of the glass cloth is improved when the sum of the boron content and the phosphorus content is 2% by mass. It can be maintained at the same level as E-glass, which is about the same.
The sum of the content of boron and the content of phosphorus in the glass can be adjusted in the process of manufacturing the glass yarn by adjusting the charged amount of glass raw materials containing boron and phosphorus. In addition, since the content of boron and phosphorus in the glass changes during the process of melting the raw materials of the glass in the process of manufacturing the glass thread, the amount of change may be incorporated to appropriately adjust the charging amount. good.

The "content of boron" and "content of phosphorus" in the glass cloth in the present embodiment are values obtained by ICP emission spectroscopic analysis.
Specifically, the boron content is measured by weighing a glass cloth sample, melting it with sodium carbonate, dissolving it with dilute nitric acid to a constant volume, and measuring boron by ICP emission spectrometry. It is the value obtained by calculating the content.
In addition, the phosphorus content was determined by weighing a glass cloth sample, thermally decomposing it with sulfuric acid, nitric acid and hydrogen fluoride, then heating and dissolving it with dilute nitric acid to a constant volume, and measuring phosphorus by ICP emission spectrometry. , is the value obtained from the content in the sample.
In the examples of the present invention described later, the ICP emission spectroscopic analysis was performed using PS3520VDDII manufactured by Hitachi High-Tech Science.

The glass cloth of this embodiment has a measurement point 80 mm inside from one end in the width direction, and a range from the measurement point toward the other end to 80 mm inside from the other end. It is preferable that the coefficient of variation of the winding hardness calculated from each winding hardness measured at measuring points provided every 200 mm is 0.025 or less.
The variation coefficient of the winding hardness is more preferably 0.021 or less, still more preferably 0.018 or less, and even more preferably 0.016 or less.
When the variation coefficient of the winding hardness is 0.025 or less, the compressive stress acting in the radial direction and the tensile stress acting in the tangential direction of the roll-shaped glass cloth act similarly in the width direction. Therefore, there is a tendency that even a low-dielectric glass cloth having a small elastic modulus and a soft texture can be obtained with a uniform woven structure without distortion.
The smaller the coefficient of variation of the winding hardness, the more uniform the woven structure of the glass cloth.

In addition, the glass cloth of the present embodiment has a measurement point 80 mm inside from one end in the width direction, and a measurement point toward the other end from the measurement point to 80 mm inside from the other end. It is preferable that the difference between adjacent measurement points is less than 2 in each winding hardness measured at measurement points provided every 200 mm in the range of .
The difference in winding hardness between adjacent measurement points is more preferably less than 1, more preferably 0.
Since the difference in winding hardness between adjacent measurement points is less than 2, even in a low-dielectric glass cloth with a small elastic modulus and a soft texture, the tensile stress acting in the tangential direction of the roll-shaped glass cloth is localized in the width direction. It is possible to suppress the displacement in the longitudinal direction caused by a large difference. Therefore, it tends to be possible to obtain a glass cloth in which wrinkles that tend to occur in the inner layer of the roll are suppressed.
The difference in winding hardness between the adjacent measurement points is ideally 0 because the smaller the difference, the more uniform the glass cloth can be, but it may be greater than 0.

The length of the roll-shaped long glass cloth of the present embodiment is not particularly limited, but is usually 200 m or more and 5,000 m or less. If the length of the glass cloth is in the range of 200 m or more and 5,000 m or less, it is possible to sufficiently obtain the effect of reducing the distortion of the woven structure such as slack, weave, and wrinkles. The length of the glass cloth is preferably longer, because a large amount of prepreg production and the like can be continuously carried out. On the other hand, the shorter the length of the glass cloth, the smaller the size and weight of the rolled glass cloth, and the better the handling and storage properties.
The length of the roll-shaped long glass cloth can be appropriately selected from the above range according to the use of the glass cloth and the purpose of processing.

The width of the glass cloth of the present embodiment is not particularly limited, but may be 500 mm or more, 600 mm or more, 700 mm or more, 800 mm or more, 900 mm or more, or 1000 mm or more, and 2000 mm or less, 1900 mm or less, 1800 mm or less, 1700 mm or less, 1600 mm or less. , 1500 mm or less, 1400 mm or less, or 1300 mm or less.
In particular, the width is preferably 800 mm or more and 1500 mm or less. The width of the glass cloth is more preferably 900 mm or more and 1400 mm or less, and still more preferably 1000 mm or more and 1300 mm or less.

When the width of the glass cloth is 800 mm or more, distortion in the uniformity of the woven structure such as sagging and wrinkles is likely to occur in the glass cloth in the weaving process, the fiber opening process, the surface treatment process, etc., but the roll shape of the present embodiment By using the above glass cloth, there is a tendency that the above distortion can be eliminated and the glass cloth can have a uniform woven structure.
In addition, when the width of the glass cloth is in the range of 800 mm or more and 1500 mm or less, the effect of reducing the distortion of the woven structure such as sag, weave, and wrinkles tends to be sufficiently obtained. A prepreg can be produced by using a resin coating machine commonly used in the production of prepreg.

The winding core tube around which the roll-shaped long glass cloth of the present embodiment is wound is preferably a winding core tube having a diameter of 100 mm or more and 500 mm or less. The diameter of the winding core tube is more preferably 130 mm or more and 350 mm or less, still more preferably 150 mm or more and 300 mm or less.
When the diameter of the winding core tube is 100 mm or more, the difference in stress acting on the glass cloth between the inner layer portion and the outer layer portion of the roll is reduced, and distortion of the woven structure such as sag, weave, and wrinkles is reduced. The effect tends to be greater.
When the diameter of the winding core tube is 500 mm or less, the diameter and weight of the roll-shaped long glass cloth can be kept small, and the handleability tends to be excellent.
The diameter of the winding core tube can be appropriately selected from the above diameter range according to the thickness, length and weight of the glass cloth and the degree of uniformity required for the glass cloth.

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

<Method for producing roll-shaped long glass cloth>
As a method of manufacturing the roll-shaped long glass cloth of the present embodiment, a method of adjusting the winding tension in the step of winding the glass cloth around the winding core tube can be preferably mentioned.
In the production of the roll-shaped long glass cloth of the present embodiment, the step of winding the glass cloth around the winding core tube is, for example, as schematically shown in FIG. It can be produced by using an apparatus for expanding the glass cloth by arranging the expander roll 13 and the nip roll 12 immediately before taking it.

In the production of rolled glass cloth, it is preferable to arrange an expander roll in the vicinity of the winding core tube or the winding roll immediately before winding the glass cloth, and pass the glass cloth through the expander roll. The expander rolls can temporarily eliminate the need to widen the width of the glass cloth, and tend to enable stable winding without depending on processes upstream of the expander rolls.
The expander roll is not particularly limited as long as it has the effect of expanding the glass cloth in both end directions by bending the glass cloth and passing it through the rolls. As the expander roll, for example, a type having a plurality of grooves inclined in the running direction of the fiber fabric on the outer peripheral surface, such as Zebra Roller C type and D type manufactured by Miyagawa Roller Co., Ltd.; Zebra Roller A manufactured by Miyagawa Roller Co., Ltd. type, B type, Composite helical roll manufactured by Meiwa Rubber Co., Ltd., a type in which rubbers with different coefficients of friction and hardness are arranged alternately at an angle to the running direction of the fiber fabric; Flat expander roll manufactured by Mitsuhashi Co., Mirabo roll, etc. A type in which the rubber installed on the outer circumference of the roll expands and contracts as it rotates; a type in which the roll axis is curved, such as an expander roll manufactured by Kansen Expander and a rubber expander roll manufactured by Kinyo; a radial crown made by Kanuki Roller. A type called a crown roll having a larger diameter at the center than the diameter at both ends, such as a type called a crown roll, can be used.

In the winding of the roll-shaped glass cloth of the present embodiment, the winding can be performed while further applying a pressure of 10 N/m or more and 500 N/m or less toward the center of the winding roll by a nip roll, that is, a nip pressure. preferable. The pressure applied by the nip rolls is preferably 10-500 N/m, more preferably 30-400 N/m, still more preferably 50-300 N/m. The nip roll is not particularly limited as long as it is commonly used.
By winding while applying a pressure of 10 N / m or more with a nip roll, it is possible to reduce the entrainment of air between the layers of the wound glass cloth, so that the outermost glass cloth and one layer A moderate frictional force acts on the glass cloth on the inner layer side. Therefore, even when compressive stress due to winding tension acts on the outermost layer of glass cloth, the outermost layer is restrained by the inner layer of glass cloth and becomes difficult to move. can be adjusted.
Winding while applying a pressure of 500 N/m or less by nip rolls tends to suppress quality problems such as fluffing due to local pressure acting on the glass cloth.

Further, the material of the nip roll is one or more selected from the group consisting of nitrile rubber, chloroprene rubber, ethylene-propylene rubber, silicone rubber, butyl rubber, styrene rubber, urethane rubber, Hibaron rubber, fluororubber, natural rubber, and the like. It is preferably a rubber-like elastic body having rubber elasticity.
Further, the above nip roll preferably has a Shore A hardness, which is durometer type A hardness, of 30 or more and 80 or less. When the Shore A hardness is 80 or less, the area on which the pressure acts becomes large, so there is a tendency that the glass cloth expanded by the expander roll can be wound up while maintaining the expanded state. Also, by shortening the space between the expander roll and the nip roll, there is a tendency that the cloth widened by the expander roll can be wound while maintaining the widened state.
When the Shore hardness is 30 or more, the nip roll itself is less strained over time, so there is a tendency that stable winding can be performed over a long period of time.

<Sheet glass cloth>
The roll-shaped long glass cloth of the present embodiment also includes a sheet-shaped glass cloth obtained by unraveling a roll-shaped glass cloth. Moreover, it is also possible to continuously manufacture prepreg or the like while unwinding the glass cloth from the roll-shaped glass cloth.
According to the present embodiment, since distortions such as sagging, crookedness, and wrinkles are reduced, it is possible to provide a glass cloth that is excellent in handleability, excellent in dimensional stability, and low in dielectric constant and dielectric loss tangent.

<Prepreg>
One of the present embodiments is a prepreg having the roll-shaped long glass cloth of the present embodiment and a matrix resin composition. The matrix resin impregnates the glass cloth.
By manufacturing a prepreg using at least a part of the roll-shaped long glass cloth of the present embodiment, dimensional stability in the step of forming a laminated plate by heating and pressurizing the prepreg and the step of forming a circuit A prepreg having excellent properties can be provided.

A prepreg produced using the roll-shaped long glass cloth of the present embodiment can be produced according to a conventional method. For example, after impregnating the glass cloth obtained by unrolling the roll-shaped glass cloth of the present embodiment with a varnish obtained by diluting a matrix resin such as an epoxy resin with an organic solvent, the organic solvent is volatilized in a drying oven. A resin-impregnated prepreg may be produced by curing a thermosetting resin to a B-stage state (semi-cured state).
As the matrix resin composition, thermosetting resins such as bismaleimide resins, cyanate ester resins, unsaturated polyester resins, polyimide resins, BT resins, and functionalized polyphenylene ether resins, in addition to the epoxy resins described above; , polyetherimide resin, liquid crystal polymer (LCP) of wholly aromatic polyester, polybutadiene, thermoplastic resin such as fluororesin; and mixed resin thereof. From the viewpoint of improving dielectric properties, heat resistance, solvent resistance, and press moldability, a resin obtained by modifying a thermoplastic resin with a thermosetting resin may be used as the matrix resin composition.
In addition, as the matrix resin composition, inorganic fillers such as silica and aluminum hydroxide in the resin; flame retardants such as bromine-based, phosphorus-based and metal hydroxides; other silane coupling agents; heat stabilizers; A resin mixed with an agent, an ultraviolet absorber, a pigment, a coloring agent, a lubricant, and the like may be used.

<Printed wiring board>
One of the present embodiments is a printed wiring board manufactured using the prepreg of the present embodiment, that is, a printed wiring board having the prepreg of the present embodiment. By manufacturing a printed wiring board using the prepreg of the present embodiment, it is possible to provide a high-quality printed wiring board with an accurate wiring circuit.

EXAMPLES The present invention will be specifically described below with reference to Examples.
In Examples and Comparative Examples, physical properties were measured by the following methods.

(1) Physical properties of glass cloth Physical properties of glass cloth, specifically, thickness of glass cloth, mass of warp and weft, diameter of filaments constituting warp and weft, number of filaments, weaving density of warp and weft, It was measured according to JIS R3420.

( ₂ ) Width insertion amount of roll-shaped glass cloth The width insertion _amount is obtained by the following formula (1 ).
Width insertion amount (%) = (W _a - W _o )/W _o x 100 (1)
Specifically, the width insertion amount was measured according to the following 1) to 4).
1) The length in the width direction of the outermost surface of the glass cloth roll was measured. At this time, the length W _a in the width direction perpendicular to the MD direction was measured, and one end of the measured portion was marked.
2) At the time when about 2 m of glass cloth was unwound from the glass cloth roll, the length W _o in the width direction of the location marked in 1) above was measured with no slack.
3) The width insertion amount was obtained by the formula (1).
4) Using the same glass cloth roll, the above measurements 1) to 3) were repeated 5 times, and the average value was taken as the width insertion amount.

(3) Winding hardness of roll-shaped glass cloth, fluctuation rate of winding hardness, difference in winding hardness between adjacent measurement points With an HP-10 type hardness tester, measure 3 points in the width direction, that is, 2 points 80 mm inside from both ends and 1 point at the center point in the width direction, and take the average value of the roll glass cloth of winding hardness.
The variability of the winding hardness and the difference in winding hardness between adjacent measurement points were also calculated using a SCHMIDT control instruments HP-10 hardness tester manufactured by Hands Schmidt & Co GmbH Schichtstr.

(4) Dimensional stability evaluation (production of test prepreg)
500 m of the surface layer side of the roll-shaped glass cloth obtained in Examples and Comparative Examples was divided into three pieces with a width of 430 mm in the same direction as the winding direction, and three glass cloths with a width of 430 mm and a length of 500 m were obtained. The surface layer side a, the surface layer side b, and the surface layer side c were obtained, respectively. Here, 500 m on the surface layer side is 500 m from the winding end point of the outermost layer.
In addition, 500 m of the inner layer side of the roll-shaped glass cloth obtained in Examples and Comparative Examples was divided into three pieces of 430 mm in width to obtain three glass cloths of 430 mm in width and 500 m in length. a, the inner layer side b, and the inner layer side c. Here, the inner layer side 500 m is 500 m from 550 m from the winding start point of the winding core tube to 50 m from the winding start point of the winding core tube.
Next, each of the six glass cloths obtained, the surface layer side a, the surface layer side b, the surface layer side c, the inner layer side a, the inner layer side b, and the inner layer side c, is coated with a prepreg using an epoxy resin varnish. to obtain six test prepregs: surface layer side a, surface layer side b, surface layer side c, inner layer side a, inner layer side b, and inner layer side c. The epoxy resin varnish includes 80 parts by mass of low-brominated bisphenol A type epoxy resin, 20 parts by mass of cresol novolac type epoxy resin, 2 parts by mass of dicyandiamide, 0.2 parts by mass of 2-ethyl-4-methylimidazole, 2-methoxy - Prepared by blending 100 parts by mass of ethanol. For prepreg coating, the glass cloth was conveyed at a speed of 3 m/min, the glass cloth was immersed in epoxy resin varnish, and excess varnish was scraped off through a slit whose gap was adjusted so that the resin content was 68% by mass. After that, drying was performed under the conditions of a drying temperature of 170° C. and a drying time of 1 minute and 30 seconds.

(Preparation of test substrate)
Using test prepregs made from different parts of a roll-shaped glass cloth, surface layer side a, surface layer side b, surface layer side c, inner layer side a, inner layer side b, and inner layer side c, a test substrate, Surface layer side a, surface layer side b, surface layer side c, inner layer side a, inner layer side b, and inner layer side c were produced.
A prepreg was cut to a size of 340 mm x 340 mm, two sheets of the prepreg were laminated, then a copper foil with a thickness of 12 μm was placed on both surfaces, and then compression molding was performed at 195 ° C. and 40 kgf / cm ² to form a test substrate. A surface layer side a, a surface layer side b, a surface layer side c, an inner layer side a, an inner layer side b, and an inner layer side c were obtained.

(Dimensional stability evaluation)
The resulting test substrate was marked at a total of 9 locations, ie, 3 locations in the vertical direction and 3 locations in the horizontal direction, at intervals of 125 mm. Then, in each of the vertical direction and the horizontal direction, six gauge point intervals between two adjacent gauge points were measured to obtain the measured value α. Next, the steel foil was removed by etching treatment, and after heating at 170° C. for 30 minutes, the gauge length was measured again to obtain the measured value β. For the warp and weft directions, the ratio of the difference between the measured value α and the measured value β to the measured value α was calculated, and the dimensional change rate between the six reference points was obtained for each of the warp and weft directions.
The measurement of the above dimensional change rate was performed on six test substrates made from different parts of the roll-shaped glass cloth, surface layer side a, surface layer side b, surface layer side c, inner layer side a, inner layer side b, and inner layer This was carried out for the side c, and the dimensional change rate values between a total of 36 reference points were obtained for each of the warp and weft directions.
Next, the average value of 36 dimensional change rate values in the warp direction obtained from six test substrates, surface layer side a, surface layer side b, surface layer side c, inner layer side a, inner layer side b, and inner layer side c. was obtained and used as the dimensional change rate in the warp direction. In addition, the standard deviation of the dimensional change rate values at 36 points in the warp direction was obtained, and the variation in the dimensional change rate in the warp direction was obtained.
Similarly, the average value of 36 dimensional change rate values in the weft direction was obtained and used as the dimensional change rate in the weft direction. In addition, the standard deviation of the dimensional change rate values at 36 points in the weft direction was obtained and used as the variation in the dimensional change rate in the weft direction.

(5) Quality of rolled glass cloth and quality of rolled glass cloth when unrolled The presence or absence of winding collapse was confirmed. ○ in the table indicates that there were no winding wrinkles or collapse during winding and after winding.
As for the quality of the roll-shaped glass cloth at the time of unrolling, the unrolled roll was visually inspected to confirm the presence or absence of irregularities caused by winding wrinkles and tight winding wrinkles. ○ in the table indicates that there were no winding wrinkles and unevenness.

<Example 1>
Both the warp and the weft were glass yarns with an average filament diameter of 4.0 μm, 50 filaments, a twist number of 1.0 Z, and a weight per unit length of 1.44×10 ⁻⁶ kg/m (elastic modulus 61 GPa, boron content 7 .35%, phosphorus content 0.02%), using an air jet loom, weaving a glass cloth with a weaving density of 95.0 warps / 25 mm and 95.5 wefts / 25 mm, and a width of 1,350 mm I got a greige machine.
After the greige fabric was heat-treated at 400° C. for 24 hours and desized, a silane coupling agent, N-β-(N-vinylbenzylaminoethyl)-γ-aminopropyltrimethoxysilane; SZ6032 (Dow Corning Toray Co., Ltd.) (manufactured by Co., Ltd.), dried at 120° C. for 1 minute after squeezing, and subjected to width processing after spreading by high-pressure water spray to obtain glass cloth A.
After the glass cloth A is expanded with an expander roll, it is spread uniformly in the width direction with a nip roll having rubber elasticity with a Shore hardness of 30 on a take-up roll under the conditions of an initial take-up tension of 300 N and a taper rate of 70%. While applying nip pressure, it was wound around a winding core tube with a diameter of 240 mm to obtain a roll-shaped glass cloth A with a thickness of 15 μm, an ignition loss of 0.89%, a width of 1,290 mm, and a length of 2,000 m. .
During the winding process, the winding tension and the nip pressure were adjusted while checking the transition of the winding hardness, and the winding was carried out while controlling the stress distribution inside the roll and the winding hardness.
The appearance of the roll-shaped glass cloth A was a uniform roll shape without quality defects such as winding wrinkles and winding collapse. The roll-shaped glass cloth A had a widening amount of 0%, an average winding hardness of 61, a fluctuation rate of winding hardness of 0.008, and a winding hardness difference of 1.
In addition, as a result of observing the roll-shaped glass cloth A when it was unrolled to produce a test substrate for evaluating dimensional stability, it was found that all layers up to the inner layer of the roll had no winding wrinkles, no unevenness, and were uniform. was in a state.

<Example 2>
Both the warp and the weft were made of glass yarn with an average filament diameter of 5.0 μm, a filament count of 100, a twist count of 1.0 Z, and a weight per unit length of 4.86×10 ⁻⁶ kg/m (elastic modulus of 61 GPa, boron content of 7 .35%, phosphorus content 0.02%), using an air jet loom, weaving a glass cloth with a weaving density of 65.0 warps / 25 mm and 67.0 wefts / 25 mm, and a width of 1,350 mm I got a greige machine. After the greige fabric was heat-treated at 400° C. for 24 hours and desized, a silane coupling agent, N-β-(N-vinylbenzylaminoethyl)-γ-aminopropyltrimethoxysilane; SZ6032 (Dow Corning Toray Co., Ltd.) A glass cloth B was obtained by immersing the glass cloth in a treatment liquid using a sintering agent (manufactured by Co., Ltd.), squeezing the solution, drying at 120° C. for 1 minute, opening the fibers with a high-pressure water spray, and processing the width.
After the glass cloth B is expanded with an expander roll, it is spread uniformly in the width direction with a nip roll having rubber elasticity with a Shore hardness of 30 on a take-up roll under the conditions of an initial take-up tension of 300 N and a taper ratio of 70%. While applying nip pressure, the glass cloth B was wound around a winding core tube having a diameter of 240 mm to obtain a roll-shaped glass cloth B having a thickness of 28 μm, an ignition loss of 0.60%, a width of 1,290 mm, and a length of 2,000 m. .
During the winding process, the winding tension and the nip pressure were adjusted while checking the transition of the winding hardness, and the winding was carried out while controlling the stress distribution inside the roll and the winding hardness.
The appearance of the roll-shaped glass cloth B was a uniform roll shape without quality defects such as winding wrinkles and winding collapse. In addition, the roll-shaped glass cloth B had a widening amount of minus 0.08%, an average value of winding hardness of 56, a fluctuation rate of winding hardness of 0.009, and a difference of winding hardness of 1.
In addition, as a result of observing the roll-shaped glass cloth B when it was unrolled to produce a test substrate for evaluating dimensional stability, it was found that all layers up to the inner layer of the roll had no wrinkles or unevenness and were uniform. was in a state.

<Comparative Example 1>
A glass cloth was produced in the same manner as in Example 2 to obtain a glass cloth H.
The glass cloth H was wound on a winding core tube with a diameter of 240 mm under the conditions of an initial winding tension of 300 N and a taper rate of 20%, a thickness of 28 μm, an ignition loss of 0.60%, a width of 1,290 mm, a length of A roll-shaped glass cloth H having a thickness of 2,000 m was obtained.
The roll-shaped glass cloth H had slight winding wrinkles from 500 m on the winding core side to the outermost layer. The width of the roll-shaped glass cloth H was 0.19%, the average value of the winding hardness was 56, the fluctuation rate of the winding hardness was 0.028, and the winding hardness difference was 3.
As a result of observing the roll-shaped glass cloth H when it was unrolled to produce a test substrate for evaluating dimensional stability, deep wrinkles accompanied by unevenness were observed in the inner layer of the roll from the winding wrinkles observed during winding. existed.

<Comparative Example 2>
A glass cloth was prepared in the same manner as in Example 2 to obtain a glass cloth I.
The glass cloth I was wound on a winding core tube with a diameter of 240 mm under the winding conditions of an initial winding tension of 200 N and a taper ratio of 20%. A roll-shaped glass cloth I of 2,000 m was obtained.
The appearance of the roll-shaped glass cloth I was a uniform roll shape with no quality defects such as winding wrinkles and winding collapse. The roll-shaped glass cloth I had a widening amount of 0.16%, an average winding hardness of 48, a fluctuation rate of winding hardness of 0.018, and a winding hardness difference of 2.
As a result of observing the roll-shaped glass cloth I while it was unrolled to prepare a test substrate for evaluating dimensional stability, it was not observed during winding, but slight winding wrinkles were present in the inner layer of the roll. was

<Comparative Example 3>
A glass cloth was produced in the same manner as in Example 2, and a glass cloth J was obtained.
The glass cloth J was wound on a winding core tube with a diameter of 240 mm under the winding conditions of an initial winding tension of 100 N and a taper ratio of 20%. A roll-shaped glass cloth J of 2,000 m was obtained.
The appearance of the roll-shaped glass cloth J was a uniform roll shape without quality defects such as winding wrinkles and winding collapse. The roll-shaped glass cloth J had a widening amount of 0.08%, an average winding hardness of 43, a fluctuation rate of winding hardness of 0.009, and a winding hardness difference of 3.
As a result of observing the roll-shaped glass cloth J while unrolling it to prepare a test substrate for dimensional stability evaluation, it was not observed during winding, but slight winding wrinkles were present in the inner layer of the roll. was

<Example 3>
Both the warp and the weft were made of glass yarn with an average filament diameter of 5.0 μm, a number of filaments of 200, a twist number of 1.0 Z, and a weight per unit length of 9.78×10 ⁻⁶ kg/m (modulus of elasticity of 61 GPa, boron content of 7 .35%, phosphorus content 0.02%), using an air jet loom, weaving a glass cloth with a weaving density of 52.5 warps / 25 mm and 52.5 wefts / 25 mm, and a width of 1,350 mm I got a greige machine. After the greige fabric was heat-treated at 400° C. for 24 hours and desized, a silane coupling agent, N-β-(N-vinylbenzylaminoethyl)-γ-aminopropyltrimethoxysilane; SZ6032 (Dow Corning Toray Co., Ltd.) (manufactured by Co., Ltd.), dried at 120° C. for 1 minute after squeezing, and subjected to width processing after spreading by high-pressure water spray to obtain glass cloth C.
After spreading the glass cloth C with an expander roll, it is spread uniformly in the width direction with a nip roll having rubber elasticity with a Shore hardness of 30 on a take-up roll under the conditions of an initial take-up tension of 240 N and a taper rate of 70%. While applying nip pressure, it was wound around a winding core tube with a diameter of 240 mm to obtain a roll-shaped glass cloth C with a thickness of 46 μm, an ignition loss of 0.56%, a width of 1,290 mm, and a length of 2,000 m. .
During the winding process, the winding tension and the nip pressure were adjusted while checking the transition of the winding hardness, and the winding was carried out while controlling the stress distribution inside the roll and the winding hardness.
The appearance of the roll-shaped glass cloth C was a uniform roll shape with no quality defects such as winding wrinkles and winding collapse. The roll-shaped glass cloth C had a widening amount of 0%, an average winding hardness of 48, a fluctuation rate of winding hardness of 0.009, and a winding hardness difference of 1.
In addition, as a result of observing the roll-shaped glass cloth C when it was unrolled to produce a test substrate for evaluating dimensional stability, it was found that all layers up to the inner layer of the roll had no wrinkles or unevenness and were uniform. was in a state.

<Example 4>
A glass cloth was produced in the same manner as in Example 3, and a glass cloth D was obtained.
After spreading the glass cloth D with an expander roll, it is spread uniformly in the width direction with a nip roll having rubber elasticity with a Shore hardness of 30 on a take-up roll under the conditions of an initial take-up tension of 400 N and a taper rate of 70%. While applying nip pressure, it was wound around a winding core tube with a diameter of 240 mm to obtain a roll-shaped glass cloth D with a thickness of 46 μm, an ignition loss of 0.54%, a width of 1,290 mm, and a length of 2,000 m. .
During the winding process, the winding tension and the nip pressure were adjusted while checking the transition of the winding hardness, and the winding was carried out while controlling the stress distribution inside the roll and the winding hardness.
The appearance of the roll-shaped glass cloth D was a uniform roll shape without quality defects such as winding wrinkles and winding collapse. In addition, the roll-shaped glass cloth D had a widening amount of minus 0.08%, an average value of winding hardness of 53, a fluctuation rate of winding hardness of 0.007, and a difference of winding hardness of 1.
In addition, as a result of observing the roll-shaped glass cloth D when it was unrolled to prepare a test substrate for evaluating dimensional stability, it was found that all layers up to the inner layer of the roll had no wrinkles or unevenness and were uniform. was in a state.

<Comparative Example 4>
A glass cloth was produced in the same manner as in Example 3 to obtain a glass cloth K.
The glass cloth K was wound around a winding core tube with a diameter of 240 mm under the conditions of an initial winding tension of 400 N and a taper rate of 20% of the winding tension. A roll-shaped glass cloth K having a length of 1,290 mm and a length of 2,000 m was obtained.
The roll-shaped glass cloth K had slight winding wrinkles from 200 m on the winding core side to the outermost layer. The roll-shaped glass cloth K had a widening amount of 0.23%, an average winding hardness of 53, a fluctuation rate of winding hardness of 0.022, and a winding hardness difference of 3.
As a result of observing the roll-shaped glass cloth K when it was unrolled to produce a test substrate for evaluating dimensional stability, wrinkles with deeper unevenness than the wrinkles observed at the time of winding were found in the inner layer of the roll. existed in

<Comparative Example 5>
A glass cloth was produced in the same manner as in Example 3, and a glass cloth L was obtained.
The glass cloth L is wound around a winding core tube with a diameter of 240 mm under the conditions of an initial winding tension of 240 N and a taper rate of 20% of the winding tension. A roll-shaped glass cloth L having a length of 1,290 mm and a length of 2,000 m was obtained.
The appearance of the roll-shaped glass cloth L was a uniform roll shape without quality defects such as winding wrinkles and winding collapse. The roll-shaped glass cloth L had a widening amount of 0.16%, an average value of winding hardness of 48, a fluctuation rate of winding hardness of 0.021, and a difference of winding hardness of 2.
As a result of observing the roll-shaped glass cloth L when it was unrolled to produce a test substrate for evaluating dimensional stability, it was not observed during winding, but slight winding wrinkles were present in the inner layer of the roll. was

<Comparative Example 6>
A glass cloth was produced in the same manner as in Example 3, and a glass cloth M was obtained.
The glass cloth M is wound around a winding core tube with a diameter of 240 mm under the conditions of an initial winding tension of 100 N and a taper rate of 20% of the winding tension. A roll-shaped glass cloth M having a length of 1,290 mm and a length of 2,000 m was obtained.
The appearance of the roll-shaped glass cloth M was a uniform roll shape without quality defects such as winding wrinkles and winding collapse. The roll-shaped glass cloth M had a widening amount of 0.08%, an average winding hardness of 44, a fluctuation rate of winding hardness of 0.018, and a winding hardness difference of 3.
As a result of observing the roll-shaped glass cloth M while unrolling it to prepare a test substrate for evaluating dimensional stability, it was not observed during winding, but slight winding wrinkles were present in the inner layer of the roll. was

<Example 5>
Both the warp and the weft are glass yarns with an average filament diameter of 5.0 μm, 200 filaments, a twist number of 1.0 Z, and a weight per unit length of 9.55×10 ⁻⁶ kg/m (elastic modulus 56 GPa, boron content 7 .35%, phosphorus content 4.00%), using an air jet loom, weaving a glass cloth with a weaving density of 52.5 warps / 25 mm and 52.5 wefts / 25 mm, and a width of 1,350 mm I got a greige machine. After the greige fabric was heat-treated at 400° C. for 24 hours and desized, a silane coupling agent, N-β-(N-vinylbenzylaminoethyl)-γ-aminopropyltrimethoxysilane; SZ6032 (Dow Corning Toray Co., Ltd.) A glass cloth E was obtained by immersing the glass cloth in a treatment liquid using a sintering agent, and squeezing the solution, drying at 120° C. for 1 minute, opening the fibers with a high-pressure water spray, and processing the width.
After spreading the glass cloth E with an expander roll, it is spread uniformly in the width direction with a nip roll having rubber elasticity with a Shore hardness of 30 on a take-up roll under the conditions of an initial take-up tension of 400 N and a taper ratio of 70%. While applying nip pressure, it was wound around a winding core tube having a diameter of 240 mm to obtain a roll-shaped glass cloth E having a thickness of 45 μm, an ignition loss of 0.89%, a width of 1,290 mm, and a length of 2,000 m. .
During the winding process, the winding tension and the nip pressure were adjusted while checking the transition of the winding hardness, and the winding was carried out while controlling the stress distribution inside the roll and the winding hardness.
The appearance of the roll-shaped glass cloth E was a uniform roll shape without quality defects such as winding wrinkles and winding collapse. In addition, the roll-shaped glass cloth E had a widening amount of minus 0.08%, an average winding hardness of 52, a fluctuation rate of winding hardness of 0.008, and a winding hardness difference of 1.
In addition, as a result of observing the roll-shaped glass cloth E when it was unrolled to produce a test substrate for evaluating dimensional stability, it was found that all layers up to the inner layer of the roll had no wrinkles or unevenness and were uniform. was in a state.

<Example 6>
Both the warp and the weft were made of glass yarn with an average filament diameter of 5.0 μm, a filament number of 100, a twist number of 1.0 Z, and a weight per unit length of 4.71×10 ⁻⁶ kg/m (elastic modulus of 56 GPa, boron content of 7 .35%, phosphorus content 4.00%), using an air jet loom, weaving a glass cloth with a weaving density of 65.0 warps / 25 mm and 67.0 wefts / 25 mm, and a width of 1,350 mm I got a greige machine. After the greige fabric was heat-treated at 400° C. for 24 hours and desized, a silane coupling agent, N-β-(N-vinylbenzylaminoethyl)-γ-aminopropyltrimethoxysilane; SZ6032 (Dow Corning Toray Co., Ltd.) (manufactured by Co., Ltd.), dried at 120° C. for 1 minute after squeezing, and subjected to width processing after spreading by high-pressure water spray to obtain glass cloth F.
After spreading the glass cloth F with an expander roll, it is spread uniformly in the width direction with a nip roll having rubber elasticity with a Shore hardness of 30 on a take-up roll under the conditions of an initial take-up tension of 300 N and a taper rate of 70%. While applying nip pressure, it was wound around a winding core tube having a diameter of 240 mm to obtain a roll-shaped glass cloth F having a thickness of 28 μm, an ignition loss of 0.91%, a width of 1,290 mm, and a length of 2,000 m. .
During the winding process, the winding tension and the nip pressure were adjusted while checking the transition of the winding hardness, and the winding was carried out while controlling the stress distribution inside the roll and the winding hardness.
The appearance of the roll-shaped glass cloth F was a uniform roll shape with no quality defects such as winding wrinkles and winding collapse. In addition, the roll-shaped glass cloth F had a width width of minus 0.08%, an average winding hardness of 56, a fluctuation rate of winding hardness of 0.008, and a winding hardness difference of 1.
In addition, as a result of observing the roll-shaped glass cloth F when it was unrolled to produce a test substrate for evaluating dimensional stability, it was found that all layers up to the inner layer of the roll had no wrinkles or unevenness and were uniform. was in a state.

<Example 7>
Both warp and weft are glass yarns with an average filament diameter of 5.0 μm, 200 filaments, a twist number of 1.0 Z, and a weight per unit length of 10.88×10 ⁻⁶ kg/m (elastic modulus 74 GPa, boron content 2 .1%, phosphorus content 0.01%), using an air jet loom, weaving a glass cloth with a weaving density of 52.5 warps / 25 mm and 52.5 wefts / 25 mm, and a width of 1,350 mm I got a greige machine. After the greige fabric was heat-treated at 400° C. for 24 hours and desized, a silane coupling agent, N-β-(N-vinylbenzylaminoethyl)-γ-aminopropyltrimethoxysilane; SZ6032 (Dow Corning Toray Co., Ltd.) A glass cloth G was obtained by immersing the glass cloth in a treatment liquid using a sintering agent (manufactured by Co., Ltd.), squeezing the solution, drying at 120° C. for 1 minute, opening the fibers with a high-pressure water spray, and processing the width.
After spreading the glass cloth G with an expander roll, it is spread uniformly in the width direction with a nip roll having rubber elasticity with a Shore hardness of 30 on a take-up roll under the conditions of an initial take-up tension of 400 N and a taper rate of 70%. While applying nip pressure, it was wound around a winding core tube having a diameter of 240 mm to obtain a roll-shaped glass cloth G having a thickness of 44 μm, an ignition loss of 0.17%, a width of 1,290 mm, and a length of 2,000 m. .
During the winding process, the winding tension and the nip pressure were adjusted while checking the transition of the winding hardness, and the winding was carried out while controlling the stress distribution inside the roll and the winding hardness.
The appearance of the roll-shaped glass cloth G was a uniform roll shape with no quality defects such as winding wrinkles and winding collapse. The roll-shaped glass cloth G had a widening amount of 0.08%, an average winding hardness of 55, a fluctuation rate of winding hardness of 0.022, and a winding hardness difference of 2.
In addition, as a result of observing the roll-shaped glass cloth G when it was unrolled to produce a test substrate for evaluating dimensional stability, it was found that all layers up to the inner layer of the roll had no wrinkles or unevenness and were uniform. was in a state.

<Comparative Example 7>
A glass cloth was produced in the same manner as in Example 7 to obtain a glass cloth N.
The glass cloth N is wound around a winding core tube with a diameter of 240 mm under the conditions of an initial winding tension of 400 N and a taper rate of 20%, a thickness of 44 μm, an ignition loss of 0.16%, a width of 1,290 mm, A roll-shaped glass cloth N having a length of 2,000 m was obtained.
The roll-shaped glass cloth N had slight winding wrinkles from 100 m on the winding core side to the outermost layer. The roll-shaped glass cloth N had a widening amount of 0.23%, an average winding hardness of 54, a fluctuation rate of winding hardness of 0.029, and a winding hardness difference of 3.
As a result of observing the roll-shaped glass cloth N when it was unrolled to produce a test substrate for evaluating dimensional stability, wrinkles with deeper unevenness than those observed at the time of winding were found in the inner layer of the roll. existed in

[Test example]
The roll-shaped glass cloths A to G and H to N obtained in Examples 1 to 7 and Comparative Examples 1 to 7 were evaluated for dimensional stability by the method described above. Table 1 shows the results.

From the results in Table 1, the roll-shaped glass cloths A to G obtained in Examples 1 to 7 show equivalent dimensional stability at three locations in the roll inner layer portion, the outer layer portion, and the width direction. , the variation in the dimensional change rate was small.

Glass cloth roll A of Example 1 having a thickness of 15 μm, a width insertion amount of 0%, and a winding hardness of 61,
Glass cloth roll B of Example 2 with a thickness of 28 μm, a width insertion amount of minus 0.08%, and a winding hardness of 56,
Glass cloth roll C of Example 3 with a thickness of 46 μm, a width insertion amount of 0%, and a winding hardness of 48,
Glass cloth roll D of Example 4 with a thickness of 46 μm, a width input minus 0.08%, and a winding hardness of 53
showed equivalent dimensional stability at three locations in the roll inner layer portion, outer layer portion, and width direction, and the variation in the dimensional change rate was small.

The glass cloth roll D of Example 4, which had a higher winding hardness than the glass cloth roll C of Example 3, had a smaller dimensional change rate and less variation in the dimensional change rate.

A glass cloth roll H with a width insertion amount of 0.19% in Comparative Example 1, which has the same thickness as the glass cloth roll B in Example 2, and a glass cloth roll with a width insertion amount of 0.16% in Comparative Example 2. I was greatly inferior in both the dimensional change rate and the variation in the dimensional change rate.
Also, the glass cloth roll J of Comparative Example 3, which has a low wound hardness of 43, was greatly inferior in both the dimensional change rate and the variation in the dimensional change rate.

A glass cloth roll K with a width insertion amount of 0.23% in Comparative Example 4, which has the same thickness as the glass cloth rolls C and D of Examples 3 and 4, and a width insertion amount of Comparative Example 5 is 0.16%. The glass cloth roll L of No. 1 was significantly inferior to the glass cloth rolls C and D in both the dimensional change rate and the variation in the dimensional change rate. Also, the glass cloth roll M of Comparative Example 6, which had a low wound hardness of 44, was greatly inferior in both the dimensional change rate and the variation in the dimensional change rate.

The glass cloth roll E of Example 5 having a thickness of 45 μm, a width insertion amount of minus 0.08%, and a winding hardness of 52 was compared with the glass cloth rolls C and D of Examples 3 and 4 having the same thickness, and the dimensional change rate was was even smaller.
The glass cloth roll F of Example 6, which has a thickness of 28 μm, a width insertion amount of minus 0.08%, and a winding hardness of 56, is compared with the glass cloth roll B of Example 2 having the same thickness, and the variation in the dimensional change rate is further increased. it was small.

The glass cloth roll G of Example 7 having a thickness of 44 μm, a width insertion amount of 0.08%, and a winding hardness of 55 is compared with the glass cloth rolls C, D, and E of Examples 3, 4, and 5 having the same thickness. , the variation in the dimensional change rate was slightly large.
The glass cloth roll N with a thickness of 44 μm, a width insertion amount of 0.19%, and a winding hardness of 54 in Comparative Example 7 has a dimensional change rate and a dimension Variation in the rate of change was also greatly inferior.

11: winding core tube 12: nip roll 13: expander roll 14: glass cloth

Claims (11)

A roll-shaped long glass cloth composed of glass yarns composed of a plurality of glass filaments as warps and wefts and wound around a winding core tube,
1) The thickness of the glass cloth is 8 μm or more and 100 μm or less,
2) the winding hardness is 45 or more and 70 or less;
3) The width insertion amount is minus 0.5% or more and less than 0.1%,
Rolled long glass cloth that satisfies The elastic modulus of the glass cloth is 50 GPa or more and 70 GPa or less.
The roll-shaped long glass cloth according to claim 1. The elastic modulus of the glass cloth is 50 GPa or more and 63 GPa or less.
The roll-shaped long glass cloth according to claim 1. The sum of the boron content and the phosphorus content is 5% by mass or more and 20% by mass or less,
The roll-shaped long glass cloth according to any one of claims 1 to 3. The sum of the boron content and the phosphorus content is 6.5% by mass or more and 20% by mass or less,
The roll-shaped long glass cloth according to any one of claims 1 to 3. The thickness of the glass cloth is 35 μm or more and 60 μm or less,
The winding hardness is 45 or more and 60 or less,
The roll-shaped long glass cloth according to any one of claims 1 to 5. The glass cloth has a thickness of 8 μm or more and less than 35 μm,
The winding hardness is 50 or more and 65 or less,
The roll-shaped long glass cloth according to any one of claims 1 to 5. A measurement point 80 mm inside from one end in the width direction, and measurements provided every 200 mm in a range from the measurement point toward the other end to 80 mm inside from the other end The coefficient of variation of the winding hardness calculated from each winding hardness measured at the point is 0.025 or less.
The roll-shaped long glass cloth according to any one of claims 1 to 7. The difference in the winding hardness of the adjacent measurement points is less than 2,
The roll-shaped long glass cloth according to claim 8. A roll-shaped long glass cloth according to any one of claims 1 to 9,
a matrix resin composition;
prepreg. Having the prepreg according to claim 10,
printed wiring board.

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