JPH07205373A - Ultra-thin composite continuous sheet and manufacturing method thereof - Google Patents

Abstract

(57) [Summary] [Structure] Polyphenylene sulfide resin and single-filament filament diameter of 10 μm or less, and 2000 woven constituent fibers
An ultrathin composite continuous sheet having a thickness of 100 μm or less, which is made of a glass fiber woven fabric of 0 fibers / in ² or more, and both surface layers of the ultrathin composite continuous sheet are at least 1/10 of the thickness of the ultrathin composite continuous sheet. The polyphenylene sulfide resin single layer having the above thickness, the inner layer portion is composed of a composite layer of the polyphenylene sulfide resin and a glass fiber woven fabric, the crystallinity of the polyphenylene sulfide resin constituting the ultrathin composite continuous sheet is 40. %, And the crystal size by X-ray diffraction is 6 nm or more, an ultrathin composite continuous sheet. [Effect] The ultra-thin composite continuous sheet of the present invention can be continuously manufactured at low cost, has excellent surface smoothness, thermal characteristics, mechanical characteristics, and is a thin material, so that it can be formed into multiple layers, particularly downsizing.
It can be used for a printed wiring board as a lightweight ultra-thin insulating base material.

Description

Detailed Description of the Invention

[0001]

The present invention relates to an ultrathin composite continuous sheet which is used as an insulating base material having excellent thermal and mechanical properties such as heat distortion temperature and solder heat resistance and excellent surface smoothness. And a manufacturing method thereof. For more details,
The present invention relates to an ultrathin composite continuous sheet made of a composite of a polyphenylene sulfide resin (hereinafter abbreviated as PPS) and a glass fiber woven fabric, and a method for producing the same.

[0002]

2. Description of the Related Art A so-called printed wiring board, which is formed by laminating a conductor made of a metal foil such as a copper foil on an insulating substrate in a plane, is used for various household electric appliances, electronic calculators, communication devices, various instruments, etc. Used in large quantities in the field.

Conventionally, as an insulating base material for a printed wiring board, a composite sheet in which a thermosetting resin such as an epoxy resin, a phenol resin or an unsaturated polyester resin is combined with a base material such as paper, glass fiber or synthetic fiber. It is used.

In all of these, a solution usually called a varnish prepared by dissolving a thermosetting resin in a solvent is applied to and impregnated on a substrate such as paper, glass fiber, synthetic fiber and the like, which is then introduced into a drier. By heating, the solvent in the varnish is evaporated and removed, and the polymerization reaction of the resin proceeds, so-called B
The prepreg was made into a state, and a predetermined number of the prepregs were stacked and heated and pressed to cure the resin. However, with this method,
Since it is necessary to remove the solvent from the varnish applied to the base material, not only is it costly to recover and process the solvent, but also the solvent scatters into the atmosphere, significantly deteriorating the working environment, and curing the resin. There was a problem that it cost a lot to do and it is not economical.

To address this problem, Japanese Patent Publication No. 60-5294
Japanese Patent Publication No. 3 discloses a printed wiring board using PPS and a specific glass fiber length. Compared with the case of thermosetting resin, process problems caused by the use of solvent and resin curing are eliminated, and a printed wiring board as an insulating base material with excellent thermal and mechanical properties can be obtained. ing.

By the way, in recent years, electronic devices have become lighter, thinner, shorter and smaller,
With higher functionality, for example, in printed wiring boards used in camera-integrated VTRs and card-type calculators, thin and lightweight multi-layer wiring boards are required as the main body becomes smaller and lighter. The thinner the printed wiring board is, the more multi-layered, smaller and lighter it is. Therefore, it is desired that the thickness of the printed wiring board is thinner. Further, when using the above-mentioned thermosetting resin composite sheet or the like to form a multilayer, after forming a circuit in each layer,
There has also been a demand for simplification of the printed wiring board manufacturing process that does not require the use of an adhesive for bonding the layers.

However, in response to such market demand,
It has become difficult to satisfy the high-level required characteristics simply by reducing the thickness of the sheet. For example, if a sheet-like molded product having a thickness of 100 μm or less is to be obtained by the method described in the above publication, the required surface smoothness, thermal characteristics, and the like are required in a mat or the like using glass fibers having a fiber length of 5 mm or more. It was not possible to obtain the one satisfying the mechanical properties.

[0008]

DISCLOSURE OF INVENTION Problems to be Solved by the Invention The present invention has been earnestly studied in view of the problems as described above, and as a result, the composition of PPS and glass fiber has made it possible to obtain surface smoothness and thermal dimensional stability. The present invention provides an ultrathin composite continuous sheet as an insulating base material having greatly improved thermal and mechanical properties typified by properties, and a method for producing the same.

[0009]

That is, the ultrathin composite continuous sheet of the present invention comprises PPS and a single yarn filament diameter of 10 μm.
m or less and the number of woven constituent fibers is 20,000 / in ²
An ultrathin composite continuous sheet having a thickness of 100 μm or less, which is made of the above glass fiber woven fabric, and both surface layers of the ultrathin composite continuous sheet have at least 1/10 or more of the thickness of the ultrathin composite continuous sheet. It is composed of a single layer of PPS, the inner layer portion is composed of a composite layer of the PPS and a glass fiber woven fabric, and the crystallinity of PPS constituting the ultrathin composite continuous sheet is 40% or more, and the crystal size by X-ray diffraction is Is 6n
It is characterized by being m or more.

Further, the manufacturing method of the ultrathin composite continuous sheet is as follows.
PPS sheet material and glass fiber woven fabric are laminated or mixed and supplied between a pair of upper and lower metal endless belts,
Melting the resin under pressure and impregnating the glass fiber fabric,
A method for producing an ultrathin composite continuous sheet, which continuously combines PPS and a glass fiber woven fabric by cooling to form an extremely thin composite sheet, which is then subjected to heat treatment at a crystallization temperature or higher and a melting point or lower. It is characterized by that.

The ultrathin composite continuous sheet of the present invention retains the excellent electrochemical properties inherent to PPS, and has more remarkable thermal and mechanical properties in terms of surface smoothness.
Especially when used as an electronic circuit board, after printing each layer circuit,
Since the matrix resin is a thermoplastic resin, each layer can be bonded by heating above the melting point of the resin without the use of an adhesive, enabling the manufacturing process of printed wiring boards to be simplified, and the thickness per layer being thin. It is possible to realize multiple layers, downsizing, and weight saving. The multilayer printed wiring board can meet the recent demands, that is, thinning, light weight, and high functionality, and bring great economic advantages to the electric industry field.

The present invention will be described in more detail below.

In order to obtain an ultrathin composite continuous sheet for a printed wiring board which has excellent surface smoothness and thermal characteristics, the present invention has the following constitution.

An ultrathin composite continuous sheet comprising PPS and a glass fiber woven fabric and having a thickness of at least 100 μm or less,
Both surface layers of the ultrathin composite continuous composite sheet are composed of at least a PPS single layer having a thickness of 1/10 or more of the thickness of the ultrathin composite continuous composite sheet. Further, the inner layer portion is a composite layer of the PPS and the glass fiber woven fabric. If both surface layers of the ultrathin composite continuous composite sheet, that is, the PPS single layer, are 1/10 or less of the thickness of the ultrathin composite continuous composite sheet, the shape of the texture of the glass fiber woven fabric is the surface layer of the ultrathin composite continuous composite sheet. The surface smoothness such as surface roughness is
It is easy to get worse.

As the form of the glass fiber woven fabric used in the present invention, woven fabrics such as plain weave, satin weave and twill weave can be preferably used. A plain weave having a good balance of mechanical properties in the warp and weft is preferable, and a non-crimp woven fabric having no crimp is more preferable.

The glass fiber woven fabric has a diameter of a single filament of glass fiber of 10 μm or less and the number of fibers constituting the weave is 2
0000 lines / in ² or more are used. If the single filament filament diameter exceeds 10 μm, it is difficult to weave a thin woven fabric, it is difficult to produce the ultrathin composite continuous sheet of the present invention, and the texture of the woven fabric is likely to affect the sheet surface, resulting in surface smoothness such as surface roughness. It is easy to get worse. Furthermore, when the number of fibers constituting the weave is less than 20,000 fibers / in ² , the dimensional change is likely to be large when the ^double ultrathin composite continuous composite sheet is heated.
Here, the number of weaving constituent fibers is the total number of single filament filaments of the warp yarn and the weft yarn per square inch, that is, the product of the number of warp yarn bundles (strands) and the number of single yarn filaments in the warp yarn bundle, and the number of weft yarn bundles. It is the sum of the product and the number of filaments of a single yarn in the weft yarn bundle.

The glass fibers may be chemically surface-treated with various compounds, if necessary, in order to improve the interfacial adhesion with PPS and enhance the reinforcing effect. Examples of various surface treatment agents include β-
(3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ
-Mercaptopropyltriethoxysilane, β-mercaptoethyltriethoxysilane and the like can be mentioned, and these can be used in combination of two or more kinds.

The PPS used in the present invention is a structural formula

[Chemical 1] Is a polymer containing 90 mol% or more, preferably 95 mol% or more of the repeating unit represented by, and when the repeating unit (para-bonded phenylene sulfide unit) is less than 90 mol%, the crystallinity of the polymer is sufficient. However, the rigidity and the heat distortion temperature are likely to decrease. Further, PPS can be constituted by less than 10 mol% of the repeating unit with a repeating unit having the following structural formula.

[0019]

[Chemical 2]

[Chemical 3]

[Chemical 4]

[Chemical 5]

[Chemical 6]

[Chemical 7] These PPS have a temperature of 300 ° C. and an apparent shear rate of 2
Under the condition of 00 sec ⁻¹ , the measured melt viscosity is 50 to
It is preferably 50,000 poise, more preferably 100.
It is suitable to be in the range of up to 5000 poise. When the melt viscosity is less than 50 poise, sufficient mechanical strength and impact resistance tend to be lowered, and when it exceeds 50,000 poise,
When glass fibers and PPS are compounded, impregnation of the glass fibers with PPS becomes insufficient, and the desired mechanical strength and thermal characteristics represented by thermal dimensional change are likely to deteriorate.

Here, the PPS is in the form of fine powder,
It is preferable that PPS is pre-compressed to the extent that it has regularity in a pellet form, a fibrous form, a film form, or a combination system thereof to form a continuous layer, but from the viewpoint of handleability, the film form is particularly preferable. Is more preferable.

An antioxidant, a heat stabilizer, a lubricant and a crystal nucleating agent can be added to the PPS used in the present invention, and other types of polymers can be added within the range not impairing the object of the present invention. A small amount can be blended.

Next, PP constituting the ultrathin composite continuous sheet
It is important that the crystallinity of S has a crystallinity of at least 40% or more, preferably 50% or more, as measured by the method described below. If the crystallinity is less than 40%, the dimensional change during heating is high. Is large and heat resistance tends to be insufficient.

Further, P which constitutes an ultrathin composite continuous sheet
The crystal size of PS is 6 nm or more. It is preferably 6.5 nm or more, more preferably 7 nm or more. The crystal size referred to in the present invention is obtained by an X-ray diffraction method, and specifically, the apparent size obtained by applying the Schller's formula to the half width of the (200) diffraction peak of a PPS crystal. Means crystal size. Crystal size is 6
If it is less than nm, the dimensional change during heating is large, and the heat resistance tends to be insufficient.

To obtain such a crystal size, heat treatment is performed. The PPS sheet-like material and the glass fiber woven fabric are laminated or mixed, supplied between a pair of upper and lower metal endless belts, the resin is melted under pressure, the glass fiber woven fabric is impregnated, and cooled to continuously In a method for producing an ultrathin composite continuous sheet in which PPS and a glass fiber woven fabric are combined and integrated with each other, after the sheet is formed by cooling,
It is important to pass through a heat treatment region having a temperature above the crystallization temperature of PS and below the melting point. The heat treatment area is more preferably installed in the above apparatus, but may be cut into a predetermined size and separately heat treated. The heat treatment temperature is 180 to 2
80 degreeC is preferable and the temperature range of 200-230 degreeC is more preferable. The heat treatment time is preferably 1 minute or longer and more preferably 5 minutes or longer. If the heat treatment temperature is lower than 180 ° C., the crystallinity tends to be low, and the growth of crystal size tends to be insufficient. Above 280 ° C, PPS
Since it exceeds the melting point of, it becomes easy to melt. Heat treatment time is 1
If it is less than minutes, the sheet itself does not easily reach the heat treatment temperature, so that the crystallinity is unlikely to increase and the crystal size is unlikely to increase.

The present invention will be described in detail below with reference to the drawings.

FIG. 1 is a schematic view showing an example of a cross section of an ultrathin composite continuous sheet of the present invention. Ultra thin composite continuous sheet 1
Is an ultrathin composite continuous sheet composed of a polyphenylene sulfide resin and a glass fiber woven fabric and having a thickness of 100 μm or less. Both surface layer portions of the ultrathin composite continuous sheet 1 are composed of a single layer 2 of polyphenylene sulfide resin having a thickness of 1/10 or more of the thickness of the ultrathin composite continuous sheet 1, and an inner layer portion thereof is a glass fiber woven fabric 3 and polyphenylene. It is composed of a composite layer with the sulfide resin 4. The glass fiber woven fabric 3 has a filament diameter of 10 μm or less and the number of fibers constituting the weave is 20000 fibers / in ² or more.

FIG. 2 is a schematic view showing an example of the method for producing the ultrathin composite continuous sheet of the present invention. The ultrathin composite continuous sheet 1 is manufactured by laminating the polyphenylene sulfide resin film 7 and the glass fiber woven fabric 6 supplied from the respective guide rolls while applying an appropriate tension, and between the pair of upper and lower metal endless belts 8. Supply, under pressure,
The polyphenylene sulfide resin film 7 and the glass fiber woven fabric 6 are preheated in the preheating zone 9, and the polyphenylene sulfide resin film 7 is melted and impregnated in the glass fiber woven fabric 6 in the heating zone 10 at a temperature higher than the melting point of the polyphenylene sulfide resin film 7. A method for producing an ultrathin composite continuous sheet in which the polyphenylene sulfide resin film 7 and the glass fiber woven fabric 6 are continuously combined and integrated by cooling in a cooling zone 11, and the ultrathin composite continuous sheet 1 is allowed to cool. After forming, the heat treatment is performed at a temperature not lower than the crystallization temperature and not higher than the melting point.

[0028]

[Characteristic Measuring Method and Effect Evaluation Method] The characteristic measuring method and effect evaluating method in the present invention are as follows.

(1) Thickness The cross section of the ultrathin composite continuous sheet was cut out, and the thickness of the ultrathin composite continuous sheet and the thickness of the PPS single layer were measured from the scanning electron micrograph of 500 times or 1000 times. Each thickness was the average thickness in one visual field, and was the average thickness at 10 measurement points.

(2) Crystallinity The crystallinity is determined by the X-ray diffraction method (see Masao Kakudo “Polymer X-Ray Diffraction” P.262-265 etc.). For a diffraction intensity curve in the range of 2θ = 10 ° and 42 °, the diffraction intensity curves of 2θ = 14 ° and 24 ° are connected by a straight line to form a baseline, and the bottom of the diffraction intensity curve is connected by a smooth curve. It is a value obtained by dividing the diffraction and the amorphous halo. In addition,
At this time, since the amorphous scattering intensity based on the glass fiber in the sample is remarkably smaller than the scattering intensity of the amorphous PPS, the diffraction from the glass fiber given to the amorphous halo was neglected and no particular correction was made. . As the X-ray generator, a Rigaku Denki D-8C type device was used, which was 35 kV-15 mA and Ni.
The Cu-Kα ray that passed through the filter was used as the X-ray source. Rigaku Denki's PMG-A2 type was used as the goniometer, and the Divergence Slit 1 °, R was used as the slit system.
receiving slit 0.15mm, Scat
We adopted tering 1 °. The 2θ scanning speed is 1 ° / min, and the chart speed is 1 cm / min. Each sample is
It was cut out into a square having a side of 20 mm and stacked to have a thickness of 0.5 mm to obtain a measurement sample.

(3) Crystal Size For the crystal size, a method of rotating the sample in a plane was adopted in order to eliminate the orientation effect of the sample, and the diffraction pattern was measured by the reflection method. An X-ray generator, an X-ray source, a goniometer, a slit system, a 2θ scanning speed, a chart speed, and a measurement sample were used in the same manner as the method for obtaining the crystallinity.

The apparent crystal size (ACS) was calculated from the full width at half maximum of the PPS (200) diffraction peak using the Scheller formula.

ACS (nm) = kλ / β cos θ β = {B ^2- (B ′) ² } ^1/2 where k = Scheller constant (k = 1) λ = X-ray wavelength (λ = 1.5418) 2θ = Bragg angle (°) β = half-width after correction (radian) B = half-width at actual measurement B ′ = half-width of standard sample for correction (Si single crystal)

(4) Heat shrinkage rate A sample is cut into a size of 20 cm on a side and the longitudinal direction (M
D) In the width direction (TD) direction, the sample length was set to 150 mm, each was cut with a single-edged razor, sandwiched between glass plates engraved on a scale with an accuracy of 0.005 mm, and magnified 200 times with an optical microscope. Enlarged and read the scale of the cut. Then, after performing heat treatment in a relaxed state at a temperature of 260 ° C. for 30 minutes, the scale was read in the same manner as above, and the average value of the number of samples = 3 was calculated as the heat shrinkage rate from the dimensional change before and after the heat treatment.

(5) Surface Roughness 10 points of 20 cm on a side are arbitrarily selected, and a universal surface profile measuring device MODEL SE-3E manufactured by Kosaka Laboratory is used to measure a needle diameter of 2 μm and a stylus moving speed of 0.5 m. / Sec, stylus load 70 mg, stylus movement direction: center line average roughness was measured under the conditions of sample width direction, cutoff 0.08 mm, and sample length 4 mm, and the average value at 10 points was measured as the surface roughness ( Ra).

(6) Tensile strength Using a "Tensilon" tensile tester, strip-shaped samples cut into a width of 5 mm and a length of 150 mm in the longitudinal direction and the width direction, respectively, have a chuck distance of 50 mm and a pulling speed of 50 mm / min. It was measured at.

[0037]

The present invention will be described in more detail with reference to the following examples, but the scope of the present invention is not limited or limited by the examples. Rather, it brings about the following applications and developments.

Example 1 Using the apparatus shown in FIG. 2, the diameter of a single filament of glass fiber was 5 μm, and the number of weaving constituent fibers was 24450 / in ^2.
Toray Co., Ltd. PPS film "Torelina" type 3000, thickness 25 μm, is fed from separate unwinders on both sides of the glass fiber woven fabric of FIG. Preheating, heating and cooling were continuously carried out to obtain an ultrathin composite continuous sheet. Molding conditions are: heating zone set temperature: 330 ° C., cooling zone set temperature: 120 ° C., linear pressure: 15 kg / cm, belt speed: 0.33 m / min, product center maximum temperature: 30
The temperature was 3 ° C. and the product removal temperature was 180 ° C. further,
The ultrathin composite continuous sheet was heat-treated at 215 ° C. for 5 minutes.

The obtained ultrathin composite continuous sheet (No. 3)
Has no curl or wrinkle and has a surface roughness (Ra) = 0.06.
The surface smoothness was good. Also, SEM
The thickness of the ultra-thin composite continuous sheet is 70
μm, and both surface layers have P of 20 μm in thickness.
It had a PS single layer and the inner layer part was composed of a composite layer of PPS and glass fiber fabric. Furthermore, the crystallinity is 42
%, Crystal size is 6.9 nm, 260 ° C. heat shrinkage is MD
Direction 0%, TD direction 0.02%, tensile strength is long (M
D) direction 25 kg / mm ² , width (TD) direction 21 kg /
It was mm ² and had excellent heat resistance and mechanical properties.

Example 2, Example 3 and Comparative Example 1 The same operation as in Example 1 was carried out except that the glass fiber having a filament diameter of 5 μm was used and the number of fibers constituting the weave was variously changed as shown in Table 1. Then, an ultrathin composite continuous sheet was obtained. The second embodiment is No. No. 2 sheet, Example 3 No. Four
Sheet, Comparative Example 1 is No. The results of evaluating the characteristics of the sheet No. 1 are shown in Tables 1 and 3.

From the results shown in Tables 1 and 3, the number of fibers constituting the glass fiber woven fabric is 20000 fibers / in ² or less (No. 1).
Then, it is clear that the heat shrinkage rate and the tensile strength are remarkably inferior.

Comparative Example 2 The glass fiber woven fabric of Example 1 was used as a glass fiber mat GHN-00-050 (K) manufactured by Honshu Denki Co., Ltd., with a basis weight of 50 g / m ^2.
(Number of glass fibers 36310 / in ² , but fiber length 1
The same operation as in Example 1 was performed except that the thickness was changed to 2 mm, and an ultrathin composite continuous sheet was obtained (No. 5). The results of evaluation of various characteristics are also shown in Tables 1 and 3.

From the results shown in Tables 1 and 3, the thickness is 100 μm.
12m long when trying to obtain the following ultra-thin composite continuous sheet
In the mat (No. 5) made of m chopped fiber,
It is apparent that the surface smoothness, the heat shrinkage ratio, and the tensile strength are remarkably inferior despite the fact that the number of constituent fibers is 20000 fibers / in ² or more.

Examples 4 to 6 and Comparative Example 3 The same operations as in Example 1 were carried out except that the thickness of the PPS film of Example 1 was changed, and as shown in Tables 1 and 3, both surface layer parts were formed. Ultrathin composite continuous sheets having various PPS single layers were obtained. The results of evaluation of various properties are shown in Tables 1 and 3.

From the results shown in Tables 1 and 3, the thickness of the PPS single layer in both surface layers of the sheet is 1/10 or less of the sheet thickness (N
o. In 6), the texture of the woven fabric affects the surface layer and the surface roughness is deteriorated, so that it is not suitable as a printed wiring board for printing a precise circuit which has been demanded in recent years.

Examples 7 to 9 and Comparative Example 4 The sheet-shaped molded article of Example 1 was treated at a heat treatment temperature of 1 as shown in Table 2.
By changing the temperature to 40 to 230 ° C., an ultrathin composite continuous sheet having various crystallinity and crystal size was obtained. The results of evaluating various properties are shown in Tables 2 and 4.

From the results shown in Tables 2 and 4, it was found that the crystallinity of PPS was less than 40% and the crystal size of PPS was less than 6 nm. It is clear that in No. 10, the heat shrinkage rate is extremely poor.

[0048]

[Table 1]

[Table 2]

[Table 3]

[Table 4]

[0049]

The ultrathin composite continuous sheet obtained by the method of the present invention can be continuously manufactured at a low cost and can be curled,
It is free from wrinkles, has excellent surface smoothness, has excellent thermal and mechanical properties represented by thermal dimensional stability, and is a thin material. Further, it can be suitably used for a printed wiring board required for downsizing and weight reduction.

[Brief description of drawings]

FIG. 1 is a schematic view showing an example of a cross section of an ultrathin composite continuous sheet of the present invention.

FIG. 2 is a schematic view showing an example of a method for producing an ultrathin composite continuous sheet of the present invention.

[Explanation of symbols]

1: Ultrathin composite continuous sheet 2: Single layer of polyphenylene sulfide resin 3: Glass fiber woven fabric 4: Polyphenylene sulfide resin 5: Composite layer of glass fiber and polyphenylene sulfide resin 6: Glass fiber woven fabric 7: Polyphenylene sulfide resin film 8: Metal endless belt 9: Preheating zone 10: Heating zone 11: Cooling zone 12: Guide roll 13: Heater 14: Product winding 15: Press roll group

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Claims (2)

[Claims] 1. A polyphenylene sulfide resin and a single-filament filament diameter of 10 μm or less, and two woven constituent fibers.
An ultrathin composite continuous sheet having a thickness of 100 μm or less and made of a glass fiber woven fabric of 0000 pieces / in ² or more,
Both surface layers of the ultrathin composite continuous sheet are composed of a single layer of polyphenylene sulfide resin having a thickness of at least 1/10 of the thickness of the ultrathin composite continuous sheet, and the inner layer portion is a composite of the polyphenylene sulfide resin and a glass fiber woven fabric. An ultrathin composite continuous sheet comprising a layer, wherein the polyphenylene sulfide resin constituting the ultrathin composite continuous sheet has a crystallinity of 40% or more and a crystal size by X-ray diffraction of 6 nm or more. 2. A polyphenylene sulfide resin sheet-like material and a glass fiber woven fabric are laminated or mixed and fed between a pair of upper and lower metal endless belts, and the polyphenylene sulfide resin is melted under pressure to impregnate the glass fiber woven fabric. Then, by cooling, a method for producing an ultrathin composite continuous sheet in which the polyphenylene sulfide resin and the glass fiber woven fabric are continuously combined and integrated, and after forming the sheet by cooling, the crystallization temperature is not lower than the melting point. The method for producing an ultrathin composite continuous sheet according to claim 1, wherein the heat treatment is performed.