Surface-treated glass cloth, prepreg and printed wiring board

Abstract

Provided are: a surface-treated glass cloth with which the reliability of a printed wiring board can be improved; a prepreg; and a printed wiring board. This surface-treated glass cloth includes a surface-treated layer containing a silane coupling agent, wherein the carbon adhesion amount of a fixed component of the surface-treated layer is in a range of 0.030-0.060 mass%, the arithmetic average height of the surface of the fixed component of the surface-treated layer is in a range of 1.0-3.0 nm, and the product of the carbon adhesion amount of the fixed component and the arithmetic average height of the surface of the fixed component is in a range of 0.060-0.100.

Description

[Technical Field]

[0001] The present invention relates to a surface-treated glass cloth, a prepreg, and a printed wiring board. [Background technology]

[0002] BACKGROUND ART Conventionally, glass cloth used in printed wiring boards is known to be surface-treated with a silane coupling agent to improve adhesion to resin (see, for example, Patent Document 1).

[0003] The surface-treated glass cloth described in Patent Document 1 has a hard texture, does not suffer from unevenness or twisting during winding, and improves production efficiency. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 5-125663 Summary of the Invention [Problem to be solved by the invention]

[0005] In recent years, with the trend toward smaller and thinner electronic devices, there is a demand for further improvement in the reliability of printed wiring boards.

[0006] In view of the above circumstances, an object of the present invention is to provide a surface-treated glass cloth capable of improving the reliability of printed wiring boards, a prepreg using the surface-treated glass cloth, and a printed wiring board using the surface-treated glass cloth. [Means for solving the problem]

[0007] The reliability of printed wiring boards can be improved by suppressing surface peeling between the glass and resin, and it is known that this is closely related to the state of the surface treatment layer of the surface-treated glass cloth. Conventionally, the state of the surface treatment layer has been evaluated by the amount of silane coupling agent attached. As a result of extensive research into the state of the surface treatment layer of surface-treated glass cloth, the inventors have found that, even with the same amount of attachment, setting the amount of components adhering to the surface of the surface-treated glass cloth and the surface height within a specific range is effective in improving the reliability (whitening distance) of printed wiring boards, and have arrived at the present invention.

[0008] Here, the whitening distance is an index showing the degree of interfacial peeling between the glass and the resin in the surface treatment layer, and therefore, the smaller the whitening distance, the higher the reliability of the printed wiring board.

[0009] Therefore, in order to achieve the above object, the surface-treated glass cloth of the present invention is a surface-treated glass cloth having a surface treatment layer on its surface, the surface treatment layer containing a silane coupling agent, the silane coupling agent having at least one methacryloyl group or acryloyl group, the carbon adhesion amount of the fixed components in the surface treatment layer is in the range of 0.030 to 0.060 mass %, the arithmetic mean height of the planes of the fixed components in the surface treatment layer is in the range of 1.0 to 3.0 nm, and the product of the carbon adhesion amount of the fixed components and the arithmetic mean height of the planes of the fixed components is in the range of 0.060 to 0.100, The adhered components are components that remain on the surface-treated glass cloth after the surface-treated glass cloth is immersed in ethanol for 60 seconds and then thoroughly dried in a dryer heated to 110°C for 30 minutes. It is characterized by:

[0010] According to the surface-treated glass cloth of the present invention, the product of the carbon adhesion amount of the adhered components and the arithmetic mean height of the surfaces of the adhered components is in the range of 0.060 to 0.100, thereby improving the reliability of printed wiring boards.

[0011] In the surface-treated glass cloth of the present invention, if the product of the carbon adhesion amount of the adhered components and the arithmetic mean height of the surfaces of the adhered components is less than 0.060, the reliability of the printed wiring board cannot be sufficiently improved. On the other hand, if the product of the carbon adhesion amount of the adhered components and the arithmetic mean height of the surfaces of the adhered components exceeds 0.100, the adhered components will form clumps, resulting in an inconsistent surface treatment and a decrease in interfacial adhesion.

[0012] In the surface-treated glass cloth of the present invention, the product of the carbon adhesion amount of the adhered components and the arithmetic mean height of the surfaces of the adhered components is preferably in the range of 0.075 to 0.097, more preferably in the range of 0.086 to 0.093.

[0014] The prepreg of the present invention is characterized by containing the surface-treated glass cloth of the present invention, and the printed wiring board of the present invention is characterized by containing the surface-treated glass cloth of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0015] Next, the embodiment of the present invention will be described in more detail.

[0016] The surface-treated glass cloth of this embodiment is a surface-treated glass cloth having a surface treatment layer on its surface, the surface treatment layer containing a silane coupling agent having at least one methacryloyl group or acryloyl group, the carbon adhesion amount of fixed components in the surface treatment layer being in the range of 0.030 to 0.060 mass%, the arithmetic mean height of the planes of the fixed components in the surface treatment layer being in the range of 1.0 to 3.0 nm, and the product of the carbon adhesion amount of the fixed components and the arithmetic mean height of the planes of the fixed components being in the range of 0.060 to 0.100, The adhered components are components that remain on the surface-treated glass cloth after the surface-treated glass cloth is immersed in ethanol for 60 seconds and then thoroughly dried in a dryer heated to 110°C for 30 minutes.

[0017] The surface-treated glass cloth of this embodiment can be produced, for example, as follows.

[0018] First, a predetermined glass batch (glass raw material) is melted and fiberized to obtain glass filaments. The glass composition constituting the glass filaments is not particularly limited, but compositions such as E glass, T glass, NE glass, and L glass are preferred. From the viewpoint of low dielectric constant and low dielectric loss tangent, NE glass and L glass are more preferable, and specifically, a composition containing, relative to the total amount, SiO2 in the range of 48.0 to 62.0 mass%, B2O3 in the range of 17.0 to 26.0 mass%, Al2O3 in the range of 9.0 to 18.0 mass%, MgO in the range of 0 to 6.0 mass%, CaO in the range of 0.1 to 9.0 mass%, Na2O, K2O, and Li2O in a total range of 0 to 0.5 mass%, TiO2 in the range of 0 to 5.0 mass%, SrO in the range of 0 to 6.0 mass%, P2O5 in the range of 0 to 6.0 mass%, and F2 and Cl2 in a total range of 0 to 3.0 mass% is even more preferable.

[0019] Here, the content of each component in the composition of the glass described above can be measured using an ICP optical emission spectrometer for the light element Li, and using a wavelength dispersive X-ray fluorescence analyzer for the other elements.

[0020] The measurement method involves cutting glass cloth (if organic matter is attached to the surface of the glass cloth or if the glass cloth is primarily contained in organic matter (resin) as a reinforcing material, the organic matter is removed by, for example, heating in a muffle furnace at a temperature between 300 and 600°C for 2 to 24 hours) into an appropriate size, placing it in a platinum crucible, and melting it in an electric furnace at 1550°C for 6 hours while stirring, to obtain homogeneous molten glass. The resulting molten glass is then poured onto a carbon plate to produce glass cullet, which is then crushed and powdered. For the light element Li, the glass powder is thermally decomposed with acid and quantitatively analyzed using an ICP atomic emission spectrometer. For other elements, the glass powder is molded into a disk shape using a press and quantitatively analyzed using a wavelength-dispersive X-ray fluorescence spectrometer. The results of these quantitative analyses are converted into oxides to calculate the content and total amount of each component, and from these values, the content (mass%) of each component mentioned above can be determined.

[0021] The diameter of the glass filaments is not particularly limited, but for printed wiring board applications it is preferably 10 μm or less, more preferably 8 μm or less, and particularly preferably in the range of 3 to 5 μm.

[0022] The glass filaments are bundled by a method known per se to form a glass fiber yarn, for example, in a number ranging from 25 to 500, preferably from 40 to 300. Note that the process of melting a glass batch, fiberizing it to obtain glass filaments, and then bundling a plurality of these glass filaments to obtain a glass fiber yarn is called spinning.

[0023] The count of the glass fiber yarn is preferably in the range of 0.8 to 135 tex, and more preferably in the range of 1 to 25 tex. The count (tex) of the glass fiber yarn corresponds to the mass (unit: g) of the glass fiber per 1000 m.

[0024] Next, the glass fiber yarns are woven as warp or weft to obtain a glass cloth. The weaving method is not particularly limited, but examples thereof include plain weave, satin weave, and twill weave, with plain weave being preferred. The weaving density of the glass fiber yarns during weaving is not particularly limited, but is preferably in the range of 10 to 150 yarns / 25 mm, and more preferably in the range of 40 to 100 yarns / 25 mm.

[0025] During the weaving process, a sizing agent is used for bundling the glass filaments and arranging the warp threads. Examples of the sizing agent include a starch-based or PVA (polyvinyl alcohol)-based film-forming agent. The sizing agent may contain an oil or a softener.

[0026] The amount of the sizing agent attached to the glass cloth is preferably in the range of 0.1 to 3 parts by mass, more preferably 0.5 to 1.5 parts by mass, per 100 parts by mass of the glass fiber yarns. Note that the range of the amount of the sizing agent attached and the amount of the sizing agent attached when not otherwise specified represent the average amount of the sizing agent attached to the warp or weft yarns.

[0027] The glass cloth obtained by the weaving process has a mass per unit area of ​​110 g / m from the viewpoint of use as a substrate for printed wiring boards. 2 On the other hand, from the viewpoint of weaving, it is preferable that the mass per unit area of ​​the glass cloth is 8 g / m or less. 2 It is preferable that this is equal to or greater than this.

[0028] Next, the glass cloth is subjected to an opening treatment. Examples of the opening treatment include an opening treatment using water flow pressure, an opening treatment using high-frequency vibrations with a liquid medium, an opening treatment using the pressure of a fluid having a surface pressure, and an opening treatment using pressure with a roll. Among the opening treatments, an opening treatment using water flow pressure or an opening treatment using high-frequency vibrations with a liquid medium is preferred because it reduces variations in the yarn width after the opening treatment for both the warp and weft yarns. Furthermore, a plurality of treatment methods may be used in combination for the opening treatment.

[0029] Next, the glass cloth that has been subjected to the fiber-opening treatment is subjected to a deoiling treatment, which can be carried out, for example, by placing the glass cloth in a heating furnace at an atmospheric temperature of 350 to 450°C for a period of 40 to 80 hours, and thermally decomposing the spinning sizing agent and weaving sizing agent that are attached to the glass cloth.

[0030] Next, the deoiled glass cloth is immersed in an aqueous solution of a surface treatment agent, excess water is squeezed out, and then the glass cloth is dried by heating at a temperature in the range of 80 to 180°C for 1 to 30 minutes, for example, at 110°C for 5 minutes, to obtain the surface-treated glass cloth of this embodiment.

[0031] The aqueous surface treatment agent solution may contain a silane coupling agent having at least one methacryloyl group or acryloyl group in a solid content of 0.1 to 2.0 mass % relative to the total amount of the aqueous surface treatment agent solution, and a weak acid (e.g., acetic acid, citric acid, propionic acid, etc.) as a pH adjuster in a solid content of 0.5 to 2.0 mass %. The weak acid acts as a catalyst for the hydrolysis reaction of the silane coupling agent, so if the amount of weak acid is insufficient, the hydrolysis of the silane coupling agent will be insufficient, resulting in a small amount of adhesion to the glass surface.

[0032] Examples of the silane coupling agent having at least one methacryloyl group include 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, and 3-methacryloxypropyltriethoxysilane. Examples of the silane coupling agent having at least one acryloyl group include 3-acryloxypropylmethyldimethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-acryloxypropylmethyldiethoxysilane, and 3-acryloxypropyltriethoxysilane. The amount of silane coupling agent attached to the glass cloth is preferably in the range of 0.01 to 5 parts by mass per 100 parts by mass of the glass fiber yarn.

[0033] Here, the adhesion of the silane coupling agent to the glass surface can be classified into two types: adhesion where the silane coupling agent is chemically and firmly fixed to the glass surface, and adhesion where the silane coupling agent is merely physically adsorbed to the glass surface. Therefore, in the present invention, the chemically and firmly fixed components excluding physically adsorbed components are defined as the fixed components, and the amount of the fixed components is defined as the fixed amount.

[0034] Specifically, the adhered components are components that adhere to the surface-treated glass cloth after the surface-treated glass cloth is immersed in ethanol for 60 seconds and thoroughly dried for 30 minutes in a dryer heated to 110° C. The carbon adhesion amount of the adhered components is measured using a total nitrogen / total carbon amount analyzer (manufactured by Sumika Chemical Analysis Center, Ltd., product name: NC-TRINITY).

[0035] The arithmetic mean height of the adhered component surface is measured by placing a surface-treated glass cloth piece cut into a 2 cm square on the sample stage of an atomic force microscope (AFM, manufactured by Park Systems, product name: NX20) and measuring the surface shape of the top part of the monofilament in the surface-treated glass cloth piece. Measurements using the atomic force microscope are performed at a scan rate of 0.60 Hz, with a pixel count of 256 vertical pixels and 256 horizontal pixels, and a surface measurement area of ​​4 μm square.

[0036] The thickness of the surface-treated glass cloth is preferably 110 μm or less from the viewpoint of use as a substrate for printed wiring boards, while it is preferably 8 μm or more from the viewpoint of ease of handling.

[0037] Next, examples of the present invention, comparative examples, and reference examples will be described. [Example]

[0038] Example 1 In this example, the glass fiber used conforms to IPC4412 standard #2116 (glass composition: NE glass, yarn used: E250, (fiber diameter 7 μm, yarn weight 20.8 g / 1000 m), warp density: 59 threads / 25 mm, weft density: 57 threads / 25 mm, unit weight: 95 g / m 2 ) was woven into a glass cloth, which was then heated at a temperature of 400 to 450°C for 60 hours to remove oil, and the glass cloth was then immersed in an aqueous solution of a glass treatment agent, excess water was squeezed out, and the glass cloth was then heated and dried at 110°C for 5 minutes to obtain a surface-treated glass cloth with a thickness of 90 μm.

[0039] The glass treatment agent aqueous solution was prepared by mixing 3-methacryloxypropyltrimethoxysilane (manufactured by Dow-Toray Industries, Inc.) as a silane coupling agent with water to a solid content of 1.0 mass % and propionic acid to a solid content of 0.5 mass %, and stirring the mixture with a magnetic stirrer for 1 hour.

[0040] The obtained surface-treated glass cloth was cut into a size of 350 mm x 400 mm to obtain a surface-treated glass cloth piece. At this time, the amount of the silane coupling agent adhered to the glass cloth was 0.13 parts by mass per 100 parts by mass of the glass fiber yarn.

[0041] Next, the surface-treated glass cloth pieces were immersed in polyphenylene ether resin varnish and pre-dried for 10 minutes at 150°C to obtain a prepreg. The polyphenylene ether resin varnish consisted of 450 parts by mass of oligophenylene ether (manufactured by Mitsubishi Gas Chemical Company, Inc., trade name: OPE-2St), 100 parts by mass of triallyl isocyanurate (manufactured by Evonik Japan Co., Ltd., trade name: TAICROS), 4 parts by mass of α,α'-di(tert-butylperoxy)diisopropylbenzene (manufactured by NOF Corporation, trade name: Perbutyl P), and 250 parts by mass of toluene (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.).

[0042] Next, four sheets of the prepreg were laminated, cellophane films were placed on top and bottom, and the laminate was heated at 205°C and 18 kgf / cm using a vacuum hot press (manufactured by Kitagawa Seiki Co., Ltd.). 2 The mixture was heated and pressed in a vacuum for 1 hour under the above conditions to obtain a laminated plate having a thickness of approximately 0.3 mm.

[0043] Next, the surface-treated glass cloth pieces obtained in this example were immersed in ethanol for 60 seconds and thoroughly dried for 30 minutes in a dryer heated to 110°C. The carbon deposition amount of the adhered components adhering to the surface-treated glass cloth pieces was then measured using a total nitrogen / total carbon analyzer (manufactured by Sumika Chemical Analysis Center, Ltd., product name: NC-TRINITY). The surface-treated glass cloth pieces obtained in this example were further cut into 2 cm squares and placed on the sample stage of an atomic force microscope (AFM, manufactured by Park Systems, product name: NX20). The arithmetic mean height of the adhered components was measured by measuring the surface profile of the top portion of the monofilament in the surface-treated glass cloth pieces, using a scan rate of 0.60 Hz, a pixel count of 256 vertical pixels and 256 horizontal pixels, and a surface measurement area of ​​4 μm square.

[0044] Next, from the measurement results, the product of the carbon deposition amount of the adhered components and the arithmetic mean height of the surfaces of the adhered components was calculated.

[0045] Next, the laminate obtained in this example was cut into a 7 cm x 4 cm piece and 2 cm long slits were made vertically and horizontally using a diamond cutter to prepare test specimens. A 1 mol / L aqueous solution of NaOH (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was placed in a beaker and heated to 60°C. The test specimens were then immersed in the solution for 30 hours. The whitening distance due to interfacial peeling between the resin and glass in the warp and weft directions was measured at 100x magnification using a digital microscope (manufactured by Keyence Corporation). Measurements were taken at 24 points in each of the warp and weft directions, and the average value was calculated to determine the whitening distance. This whitening distance due to peeling correlates with the insulation reliability of the substrate, and a shorter whitening distance is preferable.

[0046] The results are shown in Table 1. In Table 1, 3-methacryloxypropyltrimethoxysilane is referred to as "methacryl", and the aqueous solution of the glass treating agent is referred to as the treating liquid.

[0047] Example 2 In this example, a surface-treated glass cloth, a prepreg, and a laminate were obtained in exactly the same manner as in Example 1, except that the amount of propionic acid contained in the aqueous glass-treating agent solution was 1.0 mass %.

[0048] Next, the carbon adhesion amount of the fixed components and the arithmetic mean height of the surfaces of the fixed components were measured in exactly the same manner as in Example 1, except that the surface-treated glass cloth obtained in this example was used, and from the measurement results, the product of the carbon adhesion amount of the fixed components and the arithmetic mean height of the surfaces of the fixed components was calculated.

[0049] Next, except that the laminate obtained in this example was used, the whitening distance was determined in exactly the same manner as in Example 1. The results are shown in Table 1.

[0050] Example 3 In this example, the surface-treated glass cloth, prepreg, and laminate were obtained in exactly the same manner as in Example 1, except that the silane coupling agent contained in the aqueous glass treatment solution was changed from 3-methacryloxypropyltrimethoxysilane (manufactured by Dow-Toray Industries, Inc.) to 3-acryloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.).

[0051] Next, the carbon adhesion amount of the fixed components and the arithmetic mean height of the surfaces of the fixed components were measured in exactly the same manner as in Example 1, except that the surface-treated glass cloth obtained in this example was used, and from the measurement results, the product of the carbon adhesion amount of the fixed components and the arithmetic mean height of the surfaces of the fixed components was calculated.

[0052] Next, the whitening distance was determined in exactly the same manner as in Example 1, except that the laminate obtained in this example was used. The results are shown in Table 2. In Table 2, 3-acryloxypropyltrimethoxysilane is referred to as "acrylic," and the aqueous solution of the glass treatment agent is referred to as treatment liquid.

[0053] Example 4 In this example, a surface-treated glass cloth, a prepreg, and a laminate were obtained in exactly the same manner as in Example 3, except that the amount of propionic acid contained in the aqueous glass-treating agent solution was 1.0 mass %.

[0054] Next, the carbon adhesion amount of the fixed components and the arithmetic mean height of the surfaces of the fixed components were measured in exactly the same manner as in Example 1, except that the surface-treated glass cloth obtained in this example was used, and from the measurement results, the product of the carbon adhesion amount of the fixed components and the arithmetic mean height of the surfaces of the fixed components was calculated.

[0055] Next, except that the laminate obtained in this example was used, the whitening distance was determined in exactly the same manner as in Example 1. The results are shown in Table 2.

[0056] Example 5 In this example, a surface-treated glass cloth, a prepreg, and a laminate were obtained in exactly the same manner as in Example 3, except that the amount of propionic acid contained in the aqueous glass-treating agent solution was 2.0 mass %.

[0057] Next, the carbon adhesion amount of the fixed components and the arithmetic mean height of the surfaces of the fixed components were measured in exactly the same manner as in Example 1, except that the surface-treated glass cloth obtained in this example was used, and from the measurement results, the product of the carbon adhesion amount of the fixed components and the arithmetic mean height of the surfaces of the fixed components was calculated.

[0058] Next, except that the laminate obtained in this example was used, the whitening distance was determined in exactly the same manner as in Example 1. The results are shown in Table 2.

[0059] Comparative Example 1 In this comparative example, a surface-treated glass cloth, a prepreg, and a laminate were obtained in exactly the same manner as in Example 1, except that the amount of propionic acid contained in the aqueous glass-treating agent solution was changed to 0.1% by mass.

[0060] Next, the carbon adhesion amount of the fixed components and the arithmetic mean height of the surfaces of the fixed components were measured in exactly the same manner as in Example 1, except that the surface-treated glass cloth obtained in this comparative example was used, and the product of the carbon adhesion amount of the fixed components and the arithmetic mean height of the surfaces of the fixed components was calculated from the measurement results.

[0061] Next, except for using the laminate obtained in this comparative example, the whitening distance was determined in exactly the same manner as in Example 1. The results are shown in Table 1.

[0062] Comparative Example 2 In this comparative example, a surface-treated glass cloth, a prepreg, and a laminate were obtained in exactly the same manner as in Example 1, except that the amount of propionic acid contained in the aqueous glass-treating agent solution was changed to 0.3 mass %.

[0063] Next, the carbon adhesion amount of the fixed components and the arithmetic mean height of the surfaces of the fixed components were measured in exactly the same manner as in Example 1, except that the surface-treated glass cloth obtained in this comparative example was used, and the product of the carbon adhesion amount of the fixed components and the arithmetic mean height of the surfaces of the fixed components was calculated from the measurement results.

[0064] Next, except for using the laminate obtained in this comparative example, the whitening distance was determined in exactly the same manner as in Example 1. The results are shown in Table 1.

[0065] Comparative Example 3 In this comparative example, a surface-treated glass cloth, a prepreg, and a laminate were obtained in exactly the same manner as in Example 3, except that the amount of propionic acid contained in the aqueous glass-treating agent solution was changed to 0.1% by mass.

[0066] Next, the carbon adhesion amount of the fixed components and the arithmetic mean height of the surfaces of the fixed components were measured in exactly the same manner as in Example 1, except that the surface-treated glass cloth obtained in this comparative example was used, and the product of the carbon adhesion amount of the fixed components and the arithmetic mean height of the surfaces of the fixed components was calculated from the measurement results.

[0067] Next, except for using the laminate obtained in this comparative example, the whitening distance was determined in exactly the same manner as in Example 1. The results are shown in Table 2.

[0068] [Reference example 1] In this reference example, a surface-treated glass cloth, a prepreg, and a laminate were obtained in exactly the same manner as in Example 1, except that no propionic acid was added to the aqueous glass-treating agent solution.

[0069] Next, the carbon adhesion amount of the fixed components and the arithmetic mean height of the surfaces of the fixed components were measured in exactly the same manner as in Example 1, except that the surface-treated glass cloth obtained in this Reference Example was used, and from the measurement results, the product of the carbon adhesion amount of the fixed components and the arithmetic mean height of the surfaces of the fixed components was calculated.

[0070] Next, except that the laminate obtained in this Reference Example was used, the whitening distance was determined in exactly the same manner as in Example 1. The results are shown in Table 1.

[0071] [Reference example 2] In this reference example, a surface-treated glass cloth, a prepreg, and a laminate were obtained in exactly the same manner as in Example 3, except that no propionic acid was added to the aqueous glass-treating agent solution.

[0072] Next, the carbon adhesion amount of the fixed components and the arithmetic mean height of the surfaces of the fixed components were measured in exactly the same manner as in Example 1, except that the surface-treated glass cloth obtained in this Reference Example was used, and from the measurement results, the product of the carbon adhesion amount of the fixed components and the arithmetic mean height of the surfaces of the fixed components was calculated.

[0073] Next, except for using the laminate obtained in this reference example, the whitening distance was determined in exactly the same manner as in Example 1. The results are shown in Table 2.

[0074] The "whitening distance index" in Tables 1 and 2 indicates the ratio of the whitening distance to the whitening distance of a laminate when no propionic acid was added to the glass treatment agent aqueous solution (acid concentration 0%), with the whitening distance being set to 1, and a smaller whitening distance index indicates improved reliability of the printed wiring board. Specifically, the whitening distance indexes of Examples 1 and 2 and Comparative Examples 1 and 2 indicate the ratio of the whitening distance when the whitening distance of Reference Example 1 is set to 1, and the whitening distance indexes of Examples 3 to 5 and Comparative Example 3 indicate the ratio of the whitening distance when the whitening distance of Reference Example 2 is set to 1.

[0075] [Table 1]

[0076] [Table 2]

[0077] As is clear from Tables 1 and 2, the laminates using the surface-treated glass cloths of Examples 1 to 5, in which the carbon deposition amount of the fixed components of the surface treatment layer is in the range of 0.030 to 0.060 mass%, the arithmetic mean height of the planes of the fixed components of the surface treatment layer is in the range of 1.0 to 3.0 nm, and the product of the carbon deposition amount of the fixed components and the arithmetic mean height of the planes of the fixed components is in the range of 0.060 to 0.100, have a smaller whitening distance index than the laminates using the surface-treated glass cloths of Comparative Examples 1 to 3, and it is clear that reliability is improved.

Claims

1. A surface-treated glass cloth having a surface treatment layer on its surface, the surface treatment layer contains a silane coupling agent, the silane coupling agent is a silane coupling agent having at least one methacryloyl group or acryloyl group, the carbon deposition amount of the adhered component of the surface treatment layer is in the range of 0.030 to 0.060 mass %, the arithmetic mean height of the plane of the fixed components of the surface treatment layer is in the range of 1.0 to 3.0 nm, the product of the carbon deposition amount of the adhered components and the arithmetic mean height of the surfaces of the adhered components is in the range of 0.060 to 0.100, The surface-treated glass cloth is characterized in that the adhered component is a component that adheres to the surface-treated glass cloth after the surface-treated glass cloth is immersed in ethanol for 60 seconds and thoroughly dried in a dryer heated to 110°C for 30 minutes.

2. 2. The surface-treated glass cloth according to claim 1, wherein the product of the carbon adhesion amount of the adhered components and the arithmetic mean height of the surfaces of the adhered components is in the range of 0.086 to 0.

093.

3. A prepreg comprising the surface-treated glass cloth according to claim 1 or 2.

4. A printed wiring board comprising the surface-treated glass cloth according to claim 1 or 2.

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