JP7201371B2 - Manufacturing method of thermoplastic liquid crystal polymer multilayer structure - Google Patents

Description

The present invention relates to a method for producing a thermoplastic liquid crystal polymer multilayer structure composed of a thermoplastic polymer capable of forming an optically anisotropic molten phase (hereinafter referred to as a thermoplastic liquid crystal polymer).

A thermoplastic liquid crystal polymer is a material that can be adhered by thermocompression, yet has heat resistance, and is therefore useful as a dielectric layer for forming a multilayer circuit board or the like. When forming a multi-layer circuit board, it is advantageous to stack a large number of thermoplastic liquid crystal polymer layers together in order to increase production efficiency. However, the multi-layering process requires processing at high temperature, and a new manufacturing method is required for multi-layering of the liquid crystal polymer layer.

As a manufacturing method for increasing the number of layers, for example, in Patent Document 1 (Japanese Patent Laid-Open No. 2006-049502), a laminate in which a resin film and a conductor pattern are laminated is placed between hot press plates, and at least Heating/pressing the laminate from both upper and lower surfaces by the hot press plate in a state in which a cushioning member corresponding to the arrangement of the conductor pattern is interposed between one surface of the laminate and the hot press plate. A method for manufacturing a multilayer substrate is disclosed, which includes a pressing step.

Japanese Patent Application Laid-Open No. 2006-049502

In Patent Document 1, the unevenness of the surface of the multilayer substrate is transferred to the cushioning member after being heated and pressurized, and the cushioning member cannot be used repeatedly. It is characterized by However, using individual cushioning members according to the arrangement of the conductor patterns complicates the manufacturing method and is inefficient.

Accordingly, an object of the present invention is to provide a method for efficiently manufacturing a thermoplastic liquid crystal polymer multilayer structure by a simple manufacturing method while suppressing excessive flow of the thermoplastic liquid crystal polymer and deformation of the circuit layers. to do.
Another object of the present invention is to provide a method for manufacturing a thermoplastic liquid crystal polymer multilayer structure at a reduced manufacturing cost while allowing repeated use of the heat-resistant cushioning material used in the manufacturing method.

The inventors of the present invention have made intensive studies to achieve the above object, and as a result, the thermoplastic liquid crystal polymer is different from general plastics in that the melt viscosity is extremely reduced at an extremely low shear rate. When heating and pressurizing is performed with a hot press with a cushioning member interposed in order to manufacture the structure, the pattern derived from the cushioning member is transferred to the surface of the thermoplastic liquid crystal polymer multilayer structure at the thermocompression bonding temperature. I found out that

As a result of further research, (i) in a heat press, a metal plate is interposed between a cushioning material made of heat-resistant fibers and a protective material that protects the thermoplastic liquid crystal polymer multilayer structure, (ii) When the thermoplastic liquid crystal polymer multilayer structure is pressed with a heat-resistant cushioning material and a metal plate below the thermocompression bonding temperature, and the protective material is sealed with the heat-resistant cushioning material on the side of the multilayer structure, ( iii) found that a thermoplastic liquid crystal polymer multilayer structure can be fixed in a desired shape by a protective material; (v) good thermocompression bonding can be performed while the shape of the thermoplastic liquid crystal polymer multilayer structure is fixed by the protective material; The inventors have found that the surface of the liquid crystal polymer multilayer structure is not adversely affected, and that the heat-resistant cushioning material can be used repeatedly, leading to the completion of the present invention.

That is, the present invention can be configured in the following aspects.
[Aspect 1]
(i) a thermoplastic liquid crystal polymer film, (ii) a thermoplastic liquid crystal polymer film having a conductor layer on one side, and (iii) a thermoplastic liquid crystal polymer film having a conductor layer on both sides. A pre-laminate in which at least two thermoplastic liquid crystal polymer substructures are superimposed is heated and pressed in a hot press through protective materials provided on the upper and lower surfaces of the laminate to produce a thermoplastic liquid crystal polymer multilayer structure. a method,
A heat-resistant cushion material and a metal plate are arranged in order from the heat press side on at least one of the upper and lower surfaces of the preliminary laminate,
The heat press is pressurized to a first pressure below the thermocompression bonding temperature of the thermoplastic liquid crystal polymer, and (I) the preliminary laminate is pressed by the heat-resistant cushion material and the metal plate through the protective material. , (II) on the side of the pre-laminate, the end of the protective material is sealed by the pressure of the heat-resistant cushioning material, and (III) the protective material is in contact with all the side surfaces of the pre-laminate. a shape fixing step of fixing the shape of the preliminary laminate so that the preliminary laminate has a desired shape of a thermoplastic liquid crystal polymer multilayer structure by wrapping the preliminary laminate in a state;
a thermocompression bonding step of reducing the pressure from the first pressure and increasing the temperature to a thermocompression bonding temperature under a second pressure lower than the first pressure to thermocompress adjacent thermoplastic liquid crystal polymer substructures;
A method for manufacturing a thermoplastic liquid crystal polymer multilayer structure, comprising:
[Aspect 2]
The manufacturing method according to aspect 1, wherein the conductor layer is selected from the group consisting of a conductor pattern, a conductor foil, and a conductor film,
When a conductor pattern is formed on at least one of the upper surface and the lower surface of the thermoplastic liquid crystal polymer multilayer structure,
The protective material in contact with the surface on which the conductor pattern is formed is a multilayer composite material deformable according to the shape of the conductor pattern,
The manufacturing method, wherein the protective material in contact with the surface on which the conductor pattern is not formed is a single-layer sheet.
[Aspect 3]
3. The manufacturing method of aspect 2, wherein the multilayer composite is formed of a first metal foil, a pair of high density polyethylene sheets having perpendicular MD directions, a second metal foil, and a low friction film. manufacturing method.
[Aspect 4]
The manufacturing method according to any one of aspects 1 to 3, wherein the heat-resistant cushioning material is a heat-resistant fiber cushioning material.
[Aspect 5]
The manufacturing method according to aspect 4, wherein the heat-resistant fiber cushion material is a metal fiber nonwoven fabric or an organic fiber nonwoven fabric having a melting point or thermal decomposition temperature of 260°C or higher.
[Aspect 6]
The manufacturing method according to any one of aspects 1 to 5, wherein the difference between the first pressure and the second pressure is 0.8 to 2.5 MPa.
[Aspect 7]
The manufacturing method according to any one of aspects 1 to 6, wherein the longitudinal length (C _L ) and the lateral side length (C _W ) of the heat-resistant cushioning material are for the longitudinal length (P _L ) and the lateral side length (P _W ) of .
P _L +1 ≤ C _L ≤ P _L +10 (unit: cm) and P _W +1 ≤ C _W ≤ P _W +10 (unit: cm)
[Aspect 8]
The manufacturing method according to any one of aspects 1 to 7, wherein the length (M _L ) of the metal plate in the vertical direction and the length (M _W ) of the side in the horizontal direction are the same as the heat-resistant cushioning material. to the longitudinal length (C _L ) and lateral side length (C _W ) of the pre-laminate and the longitudinal length (P _L ) and lateral side length (P _W ) of the pre-laminate , a manufacturing method having the following relationship:
P _L −1.0≦M _L ≦P _L (unit: cm)
P _W −1.0≦M _W ≦P _W (Unit: cm)
C _L -11 ≤ M _L ≤ C _L -1.2 (unit: cm) and C _W -11 ≤ M _W ≤ C _W -1.2 (unit: cm)

INDUSTRIAL APPLICABILITY In the present invention, a thermoplastic liquid crystal polymer multilayer structure can be efficiently produced, and the heat-resistant cushioning material used in production can be reused repeatedly, thereby reducing production costs.

The present invention will be more clearly understood from the following description of preferred embodiments with reference to the accompanying drawings. The drawings are not necessarily drawn to scale and are exaggerated to illustrate the principles of the invention.
FIG. 2 is a schematic cross-sectional view for explaining the state before the shape fixing step in the method for manufacturing a thermoplastic liquid crystal polymer multilayer structure according to the first embodiment of the present invention; 1. It is a schematic sectional drawing for demonstrating the state which applies a pressure to a preliminary|backup laminated body in a shape fixing process about embodiment of FIG. FIG. 4 is a schematic cross-sectional view for explaining the state before the shape fixing step in the method for manufacturing a thermoplastic liquid crystal polymer multilayer structure according to the second embodiment of the present invention; FIG. 10 is a schematic cross-sectional view for explaining the state before the shape fixing step in the method for manufacturing a thermoplastic liquid crystal polymer multilayer structure according to the third embodiment of the present invention; FIG. 5 is a schematic cross-sectional view for explaining a state in which pressure is applied to the preliminary laminate in the shape-fixing step in the embodiment of FIG. 4; FIG. 10 is a schematic cross-sectional view for explaining the state before the shape-fixing step in the method for producing a thermoplastic liquid crystal polymer multilayer structure according to Comparative Examples 4 to 8; FIG. 10 is a schematic cross-sectional view for explaining the state before the shape fixing step in the method for producing a thermoplastic liquid crystal polymer multilayer structure according to Comparative Examples 9 to 13;

In the method for producing a thermoplastic liquid crystal polymer multilayer structure of the present invention, (i) a thermoplastic liquid crystal polymer film, (ii) a thermoplastic liquid crystal polymer film having a conductor layer on one side, and (iii) a conductor layer on both sides. A pre-laminate in which at least two thermoplastic liquid crystal polymer substructures selected from the group consisting of thermoplastic liquid crystal polymer films having surfaces are superimposed on each other is heated in a heat press from both upper and lower sides by specific heating and pressure control. Compression is applied to produce a thermoplastic liquid crystal polymer multilayer structure in which adjacent thermoplastic liquid crystal polymer substructures are adhered.

(thermoplastic liquid crystal polymer)
The thermoplastic liquid crystalline polymer is composed of a liquid crystalline polymer that can be melt-molded (or a polymer that can form an optically anisotropic melt phase). Although the chemical structure is not particularly limited, examples thereof include thermoplastic liquid crystal polyesters and thermoplastic liquid crystal polyester amides into which amide bonds are introduced.

Further, the thermoplastic liquid crystal polymer may be a polymer obtained by introducing an isocyanate-derived bond such as an imide bond, a carbonate bond, a carbodiimide bond or an isocyanurate bond into an aromatic polyester or an aromatic polyester amide.

Specific examples of the thermoplastic liquid crystalline polymer used in the present invention include known thermoplastic liquid crystalline polyesters and thermoplastic liquid crystalline polyester amides derived from compounds classified into the following examples (1) to (4) and derivatives thereof. can be mentioned. However, it goes without saying that there is an appropriate range of combinations of various raw material compounds in order to form a polymer capable of forming an optically anisotropic molten phase.

(1) Aromatic or aliphatic dihydroxy compound (see Table 1 for representative examples)

(2) Aromatic or aliphatic dicarboxylic acid (see Table 2 for representative examples)

(3) Aromatic hydroxycarboxylic acid (see Table 3 for representative examples)

(4) Aromatic diamine, aromatic hydroxylamine or aromatic aminocarboxylic acid (see Table 4 for representative examples)

Copolymers having the structural units shown in Tables 5 and 6 are typical examples of liquid crystal polymers obtained from these raw material compounds.

Among these copolymers, preferred are polymers containing at least p-hydroxybenzoic acid and/or 6-hydroxy-2-naphthoic acid as repeating units, particularly (i) p-hydroxybenzoic acid and 6-hydroxy- A polymer containing repeating units with 2-naphthoic acid, or (ii) at least one aromatic hydroxycarboxylic acid selected from the group consisting of p-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid, and at least one Copolymers containing repeating units of an aromatic diol and at least one aromatic dicarboxylic acid are preferred.

For example, in the polymer (i), when the thermoplastic liquid crystal polymer contains at least repeating units of p-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid, the repeating unit (A) of p-hydroxybenzoic acid and the molar ratio (A)/(B) of the repeating unit (B) to 6-hydroxy-2-naphthoic acid is (A)/(B) = about 10/90 to 90/10 in the liquid crystal polymer. is desirable, more preferably (A) / (B) = about 15/85 to 85/15, more preferably (A) / (B) = 20/80 to 80/20 It may be to some extent.

In the case of the polymer (ii), at least one aromatic hydroxycarboxylic acid (C) selected from the group consisting of p-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid and 4,4'-dihydroxy at least one aromatic diol (D) selected from the group consisting of biphenyl, hydroquinone, phenylhydroquinone, and 4,4'-dihydroxydiphenyl ether; The molar ratio of each repeating unit in the liquid crystal polymer of at least one aromatic dicarboxylic acid (E) is aromatic hydroxycarboxylic acid (C): the aromatic diol (D): the aromatic dicarboxylic acid (E) = (30-80): (35-10): It may be about (35-10), more preferably (C): (D): (E) = (35-75): (32.5 ~ 12.5): (32.5 to 12.5), more preferably (C): (D): (E) = (40 to 70): (30 to 15): (30 to 15) may be sufficient.

Further, the molar ratio of repeating units derived from 6-hydroxy-2-naphthoic acid in the aromatic hydroxycarboxylic acid (C) may be, for example, 85 mol% or more, preferably 90 mol% or more, and more Preferably, it may be 95 mol % or more. The molar ratio of repeating units derived from 2,6-naphthalenedicarboxylic acid in the aromatic dicarboxylic acid (E) may be, for example, 85 mol% or more, preferably 90 mol% or more, more preferably 95 mol. % or more.

In addition, the aromatic diol (D) is a repeating unit derived from two different aromatic diols selected from the group consisting of hydroquinone, 4,4'-dihydroxybiphenyl, phenylhydroquinone, and 4,4'-dihydroxydiphenyl ether. (D1) and (D2) may be used, in which case the molar ratio of the two aromatic diols may be (D1)/(D2)=23/77 to 77/23, more preferably may be 25/75 to 75/25, more preferably 30/70 to 70/30.

Further, the molar ratio of the repeating structural unit derived from the aromatic diol and the repeating structural unit derived from the aromatic dicarboxylic acid is preferably (D)/(E)=95/100 to 100/95. Outside this range, the degree of polymerization tends to be low and the mechanical strength tends to be low.

The ability to form an optically anisotropic molten phase as referred to in the present invention can be identified by, for example, placing a sample on a hot stage, heating the sample at an elevated temperature in a nitrogen atmosphere, and observing light transmitted through the sample. .

Preferred thermoplastic liquid crystal polymers have a melting point (hereinafter referred to as Tm) in the range of 260 to 360°C, more preferably 270 to 350°C. Tm is obtained by measuring the temperature at which the main endothermic peak appears with a differential scanning calorimeter (Shimadzu Corporation DSC).

The thermoplastic liquid crystal polymer includes thermoplastic polymers such as polyethylene terephthalate, modified polyethylene terephthalate, polyolefin, polycarbonate, polyarylate, polyamide, polyphenylene sulfide, polyether ether ketone, and fluororesin within the range that does not impair the effects of the present invention. , various additives, fillers, and the like may be added.

A thermoplastic liquid crystal polymer film is obtained, for example, by extruding a melt-kneaded product of the thermoplastic liquid crystal polymer. Any method can be used as the extrusion molding method, but the well-known T-die method, inflation method and the like are industrially advantageous. In particular, in the inflation method, stress is applied not only in the mechanical axis direction (hereinafter abbreviated as MD direction) of the thermoplastic liquid crystal polymer film, but also in the direction orthogonal to this (hereinafter abbreviated as TD direction). Since the film can be stretched uniformly in both directions, it is possible to obtain a thermoplastic liquid crystal polymer film with controlled molecular orientation in the MD and TD directions, dielectric properties, and the like.

For example, in extrusion molding by the T-die method, the melt sheet extruded from the T-die may be stretched not only in the MD direction of the thermoplastic liquid crystal polymer film but also in both the MD direction and the TD direction at the same time to form a film. Alternatively, a melt sheet extruded from a T-die may be stretched once in the MD direction and then stretched in the TD direction to form a film.

Further, in extrusion molding by the inflation method, a predetermined draw ratio (corresponding to the draw ratio in the MD direction) and blow ratio (corresponding to the draw ratio in the TD direction) are applied to the cylindrical sheet melt-extruded from the ring die. It may be stretched to form a film.

The draw ratio for such extrusion molding may be, for example, about 1.0 to 10, preferably about 1.2 to 7, more preferably about 1.0 to 10, as a draw ratio (or draw ratio) in the MD direction. It may be about 3 to 7. The draw ratio (or blow ratio) in the TD direction may be, for example, about 1.5 to 20, preferably about 2 to 15, more preferably about 2.5 to 14.

(Integration process of conductor layer and thermoplastic liquid crystal polymer film)
When forming a conductor layer (a signal layer, a power layer, a ground layer such as a conductive layer, such as a conductor pattern, a conductor foil, a conductor film, etc.) on a thermoplastic liquid crystal polymer film, a known or commonly used method is used. Depending on the method, the step of integrating the conductor layer and the thermoplastic liquid crystal polymer film can be performed. This integration step may produce a thermoplastic liquid crystal polymer film having a conductor layer on one side or a thermoplastic liquid crystal polymer film having conductor layers on both sides.
For example, a single-sided metal-clad laminate or a double-sided metal-clad laminate is formed by thermocompression bonding a metal foil or the like to a thermoplastic liquid crystal polymer film, and etching is performed as necessary to form the required conductor layer shape. You may

As the conductor forming the conductor layer, various metals having conductivity such as gold, silver, copper, iron, nickel, aluminum, or alloy metals thereof may be used. The thickness of the conductor layer can be appropriately set as required, and may be, for example, about 5 to 50 μm, more preferably 8 to 35 μm.

Thus, the thermoplastic liquid crystal polymer substructures used in the thermoplastic liquid crystal polymer multilayer structure include (i) a thermoplastic liquid crystal polymer film, (ii) a thermoplastic liquid crystal polymer film having a conductor layer on one side, and (iii) Thermoplastic liquid crystal polymer films can be made with conductor layers on both sides.

(Deaeration drying process)
If desired, the thermoplastic liquid crystal polymer substructure may be subjected to a degassing drying step to remove air and moisture present in the thermoplastic liquid crystal polymer film. The degassing drying step may be performed on individual thermoplastic liquid crystal polymer substructures and combinations thereof prior to the shape setting step, or may be performed on the prelaminate as part of the shape setting step. may be performed, or both may be performed.

When performed prior to the shape-fixing step, the deaeration drying step is not particularly limited in timing as long as it is performed before the shape-fixing step. , in the thermoplastic liquid crystal polymer film, or as part of the integration process of the thermoplastic liquid crystal polymer film and the conductor layer.
The degassing and drying process can improve the thermal adhesiveness of the thermoplastic liquid crystal polymer substructures, and can improve the interlayer adhesiveness of the thermoplastic liquid crystal polymer substructures.

The shape of the thermoplastic liquid crystal polymer substructure to be subjected to the degassing drying step is not particularly limited as long as the thermoplastic liquid crystal polymer film can be degassed and dried. For example, in the degassing drying process, the thermoplastic liquid crystal polymer substructure may be the thermoplastic liquid crystal polymer film itself, or a thermoplastic liquid crystal polymer film having a conductor layer formed on one or both sides of the thermoplastic liquid crystal polymer film. It may be provided as a sheet of polymer substructures. Additionally, these thermoplastic liquid crystal polymer substructures may optionally be provided as rolls.

Furthermore, if desired, the thermoplastic liquid crystal polymer substructure is a multilayer laminate of a plurality of thermoplastic liquid crystal polymer substructures (e.g., a multilayer laminate of multiple layers of thermoplastic liquid crystal polymer substructures, a temporary assembly). It may be subjected to the degassing drying step in the state of a multi-layer circuit, etc.).

In the degassing drying step, the thermoplastic liquid crystal polymer substructure is subjected to degassing drying under a specific vacuum (e.g. vacuum drying) and/or degassing drying under heat (e.g. heat drying), It is possible to reduce air and water present inside and on the surface of the thermoplastic liquid crystal polymer film to an extremely high degree. In the thermoplastic liquid crystal polymer substructure that has undergone such a deaeration drying process, it is possible to improve its thermal adhesiveness.

For example, a thermoplastic liquid crystal polymer film subjected to a degassing drying process can achieve high adhesiveness without performing a softening treatment that destroys the skin layer. However, the present invention does not deny the softening treatment. If necessary, the thermoplastic liquid crystal polymer film may be subjected to surface treatment such as softening treatment.

In the degassing drying step, the thermoplastic liquid crystal polymer substructure is (a) degassed and dried under vacuum at a degree of vacuum of 1500 Pa or less for 30 minutes or more, and/or (b) in the range of 80°C to 300°C. The thermoplastic liquid crystal polymer film can be degassed and dried by degassing and drying under heating. In the degassing drying step, degassing drying may be performed under conditions that satisfy either (a) the degassing drying step under vacuum or (b) the degassing drying step under heating. ) and (b) are preferably satisfied.

When degassing drying is performed under conditions that satisfy both (a) and (b), degassing drying is performed under conditions that satisfy both (a) and (b) at the same time (i.e., under vacuum heating). or a degassing drying step in which conditions (a) and (b) are performed separately for the thermoplastic liquid crystalline polymer substructure, i.e., in order from (a) to (b), or (b ) to (a) may be performed separately in the order of degassing and drying.

In the case where the degassing and drying steps are performed separately, between (a) and (b), or between (b) and (a), within a range that does not adversely affect the thermal adhesiveness of the thermoplastic liquid crystal polymer film. A separate drying step may be performed.

Moreover, in the degassing drying step, from the viewpoint of improving the degassing drying property, the degassing drying may be performed under no pressure (under pressure release) in which substantially no pressure is applied. For example, the degassing drying step may be performed under a low pressure or pressure release state (for example, under a pressure of about 0 to 0.7 MPa, preferably under a pressure of about 0 to 0.5 MPa).

(a) Deaeration drying under vacuum may be performed at a degree of vacuum of 1500 Pa or less, preferably 1300 Pa or less, more preferably 1100 Pa or less. When the degassing drying under vacuum is performed independently, it may be performed at normal temperature (for example, 10 to 50 ° C., preferably 15 to 45 ° C.), but from the viewpoint of increasing the degassing drying efficiency, under heating. You can go with The heating temperature in that case may be, for example, about 50 to 300°C (eg, 50 to 250°C), preferably about 80 to 250°C, more preferably about 80 to 200°C.

(b) Deaeration drying under heating may be carried out at a temperature of 80 to 300°C, preferably 80 to 250°C, more preferably 80 to 200°C. Further, for the deaeration drying under heating, a predetermined temperature range may be set with respect to the melting point Tm of the thermoplastic liquid crystal polymer film. In that case, for example, it may be heated in the range of (Tm-235) ° C. to (Tm-10) ° C. (eg, in the range of (Tm-200) ° C. to (Tm-50) ° C.), preferably The range of (Tm-225) ° C. to (Tm-50) ° C. (for example, the range of (Tm-190) ° C. to (Tm-60) ° C.), more preferably (Tm-215) ° C. to (Tm-70 )° C. (for example, in the range of (Tm-180)° C. to (Tm-70)° C.).

By heating in a specific temperature range as described above, while suppressing the rapid generation of moisture from the film, the water in the film (for example, the inside of the film and the film surface) is degassed and dried as water vapor. , it is possible to increase the kinetic energy of the air present on the surface to deaerate and dry the film surface.

When deaeration drying under heating is performed alone, it may be performed under conditions that do not include a degree of vacuum of 1500 Pa or less, for example, under atmospheric pressure (or under normal pressure) without adjusting the pressure. However, if necessary, the heating may be performed under conditions reduced from atmospheric pressure (for example, more than 1500 Pa and less than 100000 Pa, preferably about 3000 to 50000 Pa).

The time required for the degassing drying step can be appropriately set depending on various conditions such as the state of the thermoplastic liquid crystal polymer film in the thermoplastic liquid crystal polymer substructure, the degree of vacuum and/or the heating temperature. From the viewpoint of removing moisture and air from the whole, for example, each degassing drying step (under vacuum, under heating, under vacuum heating) is the same or different, 30 minutes or more, 40 minutes or more, or 50 minutes or more 6 hours or less, 4 hours or less, 3 hours or less, 2 hours or less, or 1.5 hours or less.
In addition, the time required for the degassing and drying step may be set as appropriate, for example, in anticipation of the time when the moisture content of the thermoplastic liquid crystal polymer film reaches a predetermined range (for example, 380 ppm or less, 300 ppm or less, or 200 ppm or less). good.

As described above, in the degassing drying step, when (a) degassing drying under vacuum and (b) degassing drying under heat are combined, the thermal adhesiveness of the thermoplastic liquid crystal polymer substructure is reduced. Either of (a) degassing drying under vacuum and (b) degassing drying under heat may be performed first as long as it can be improved, but preferably, heating is performed as the first degassing drying step. After degassing drying under vacuum, degassing drying under vacuum may be performed as a second degassing drying step.
Specifically, for example, the degassing drying step includes heating in the range of 80 ° C. to 300 ° C. for a predetermined time to perform degassing drying, a first degassing drying step, a vacuum degree of 1500 Pa or less, and a predetermined and a second degassing drying step in which degassing drying is performed for a period of time. When performing these degassing drying steps, the conditions described above can be appropriately combined.

[Manufacturing method according to the first embodiment]
A method for manufacturing a thermoplastic liquid crystal polymer multilayer structure according to one embodiment of the present invention will now be described with reference to FIGS. FIG. 1 is a schematic cross-sectional view for explaining the state before the shape fixing step in a method for manufacturing a thermoplastic liquid crystal polymer multilayer structure according to one embodiment of the present invention, and FIG. 2 is a preliminary lamination in the shape fixing step. FIG. 4 is a schematic cross-sectional view for explaining a state in which pressure is applied to the body;

As shown in FIG. 1, in the first embodiment of the present invention, a heat press (preferably a vacuum heat press) 100 having an upper platen 110 and a lower platen 120 heats a preliminary laminate 130 from both upper and lower surfaces. and pressurized. The preliminary laminate 130 is composed of three thermoplastic liquid crystal polymer substructures 131, 132 and 133 in order from the top. The thermoplastic liquid crystal polymer substructures 131 and 132 have conductor patterns formed only on the upper surfaces, and the thermoplastic liquid crystal polymer substructure 133 has conductor patterns formed on the upper and lower surfaces. Therefore, conductor patterns are formed as conductor layers on the upper and lower surfaces of the preliminary laminate 130 .

A first protective material 142 is provided above the preliminary laminate 130 , and a second protective material 144 is provided below the preliminary laminate 130 . Between the first protective member 142 and the upper platen 110, a first heat-resistant cushion member 150 is arranged on the upper platen 110 side, and a first metal plate 152 is arranged on the first protective member 142 side. is set. On the other hand, between the second protective material 144 and the lower platen 120, a second heat-resistant cushion material 160 is arranged on the lower platen 120 side, and a second metal plate 162 is arranged on the second protective material 144 side. is arranged.

(Shape fixing process)
In the shape-fixing step, the heat press is pressurized to a first pressure at a temperature lower than the thermocompression bonding temperature of the thermoplastic liquid crystal polymer, and (I) the pre-laminated body is secured to the heat-resistant cushioning material and the heat-resistant cushioning material through the protective material. (II) on the side of the pre-laminate, the end of the protective material is sealed by pressurization of the heat-resistant cushioning material; (III) the protective material covers the entire pre-laminate; By wrapping the pre-laminate in contact with the sides of the pre-laminate, the pre-laminate is shaped into the desired thermoplastic liquid crystal polymer multilayer structure shape.
For example, as shown in FIG. 2, first, according to pressure from the hot press machine 100, upper and lower platens 110, 120, first and second heat-resistant cushion materials 150, 160, first and second metal plates 152, 162 and first and second protective members 142 and 144, the preliminary laminate 130 is sandwiched from above and below, and the preliminary laminate 130 is shaped into a desired thermoplastic liquid crystal polymer multilayer structure. The pressure is increased to 1, and the pre-laminate 130 is pressurized for a predetermined time. In this shape-fixing step, the first and second heat-resistant cushion materials 150 and 160 sink into the upper and lower surfaces of the preliminary laminate 130 according to the thickness of the preliminary laminate 130 by the first pressure.

As a result, the upper and lower surfaces of the preliminary laminate 130 are pressed by the first and second heat-resistant cushion materials 150, 160 via the first and second protective materials 142, 144, respectively. On the other hand, on the side of the preliminary laminate 130 where the preliminary laminate is not arranged, the first and second heat-resistant cushioning materials are applied while the first and second protective materials 142 and 144 are in contact with each other. Pressurized by 150,160.

As a result, the first and second protective materials 142 and 144 protect the portions in contact with the upper surface and the lower surface of the preliminary laminate 130, respectively, and protect the preliminary laminate while contacting all the side surfaces of the preliminary laminate 130. It wraps around the body 130 and is sealed with first and second heat-resistant cushioning materials 150 and 160 on the sides of the pre-laminate 130 . By forming a seal structure with the first and second protective members 142 and 144, the shape of the preliminary laminate 130 including the side surfaces is fixed. As a result, the pre-laminate 130 is shape-fixed into the shape of the desired thermoplastic liquid crystal polymer multilayer structure, and the thermoplastic liquid crystal polymer of the pre-laminate 130 is compressed under pressure in a subsequent thermocompression bonding process. It can be suppressed to flow sideways.

The first pressure applied to the preliminary laminate in the shape-fixing step is not particularly limited as long as the shape of the heat-resistant cushioning material can be deformed to give the preliminary laminate a desired shape. It may be from 2 to 6 MPa, preferably from 2.5 to 5.5 MPa, more preferably from 3 to 5 MPa, and even more preferably from 3.5 to 4.5 MPa.

The step of increasing the pressure to the first pressure may be performed at room temperature, or if it is below the thermocompression bonding temperature in the thermocompression bonding step (for example, below the glass transition temperature of the thermoplastic liquid crystal polymer to be fused). , may be in an appropriately heated state. When heating, the heating may be performed before the pressure is increased. By heating, the preliminary laminate can be degassed and the adhesiveness can be enhanced. note that,
The peak temperature of tanD that appears when the temperature is raised from 25° C. to 220° C. at a rate of 3° C./min in dynamic viscoelasticity measurement (DMA) is defined as the glass transition temperature.

As described in the degassing drying step, the degassing drying step may be performed on the pre-laminate as part of the shape setting step. In this case, the degassing drying conditions may be performed with reference to the conditions described in the degassing drying step described above. From the viewpoint of drying the pre-laminated body by deaeration, it is preferable to heat the pre-laminated body before increasing the pressure to the first pressure. For example, the heating temperature is not particularly limited as long as it is lower than the thermocompression bonding temperature in the thermocompression bonding step. It may be from (T-180) to (T-70)°C, more preferably from (T-160) to (T-90)°C. Specifically, for example, it may be carried out by heating in the range of 80 to 300 ° C., preferably 80 to 200 ° C., more preferably in the range of 100 to 200 ° C., still more preferably in the range of 115 to 200 ° C. may be broken.
Further, the time for holding at the heating temperature may be, for example, 5 to 120 minutes, preferably about 5 to 60 minutes, and the moisture content of the thermoplastic liquid crystal polymer film is within a predetermined range (for example, 380 ppm or less, 300 ppm or less, or 200 ppm or less) may be set as appropriate.

(Thermocompression process)
In the thermocompression bonding step, the pressure is reduced from a first pressure, and the temperature is increased to a thermocompression bonding temperature under a second pressure lower than the first pressure to thermocompress adjacent thermoplastic liquid crystal polymer substructures.
Specifically, after the shape of the preliminary laminate is fixed to the desired shape by the shape fixing step, the pressure is then reduced to a second pressure lower than the first pressure. Since the heat-resistant cushioning material has impact resilience while being deformed, it is possible to maintain the shape of the preliminary layered body without changing its position with respect to the protective material while snuggling up to the shape of the preliminary layered body. In particular, since the heat-resistant fiber cushion material used in the present invention is formed of fibers, even if the pressure is reduced from the first pressure to a predetermined pressure, the shape of the voids between the fibers is fixed as it is under pressure. can do. As a result, even if the pressure is reduced, the shape of the preliminary laminate can be maintained without changing the positions of the already fixed heat-resistant cushioning material and protective material.

The second pressure maintains the shape of the deformed heat-resistant cushioning material and protective material, fixes the pre-laminated body in a predetermined shape, and is in a range where the thermoplastic liquid crystal polymer molecules do not excessively flow according to the heating temperature. For example, it may be 0.5 to 3.5 MPa, preferably 1.0 to 3.0 MPa, more preferably 1.5 to 2.5 MPa.

The difference between the first pressure and the second pressure may be, for example, approximately 0.8 to 2.5 MPa, preferably approximately 1.3 to 2.3 MPa.

For example, as shown in FIG. 2, in the thermocompression bonding step, the temperature of the pre-laminate 130 is raised to the thermocompression bonding temperature under the second pressure, and held for a predetermined time, so that the adjacent thermoplastic liquid crystal polymer is The sub-structures 131, 132, 133 are thermo-compressed together.

By arranging the first and second metal plates 152, 162, the surface of the pre-laminate 130, such as patterns derived from the first and second heat-resistant cushion materials 150, 160, is removed in the thermocompression bonding process. You can prevent it from being reflected in the image.

On the other hand, during thermocompression bonding, the conductor patterns formed on the upper and lower surfaces of the pre-laminate 130 are protected by the protective materials 142 and 144, so that the conductor patterns are not displaced even when pressure is applied from the metal plates. Thermocompression bonding can be performed. As such a protective material, a multilayer composite material that can be deformed according to the shape of the conductor pattern is preferable.

The thermocompression bonding temperature is not limited as long as any one of the adjacent units can be fused between the thermoplastic liquid crystal polymers forming the thermoplastic liquid crystal polymer substructure.

For example, the thermocompression bonding temperature may be determined after knowing in advance the thermal bonding temperature of the thermoplastic liquid crystal polymer substructure. For example, when the melting point of the thermoplastic liquid crystal polymer film to be fused is (Tm), the thermocompression bonding temperature may be in the range of (Tm−20) to (Tm+20)° C., preferably (Tm− 15) to (Tm+5)°C. From the viewpoint of reliable fusion bonding, the thermoplastic liquid crystal polymer film to be fused may be the thermoplastic liquid crystal polymer film having the highest melting point in the pre-laminate.

Also, the time for holding at the thermocompression bonding temperature may be, for example, about 1 to 30 minutes, preferably about 1 to 15 minutes.

After the thermocompression bonding step, the temperature is lowered, the pressure is released, and then the thermoplastic liquid crystal polymer multilayer structure is removed from the protective material to obtain a thermoplastic liquid crystal polymer multilayer structure having a desired shape (laminate structure). can. In addition, since the heat-resistant cushioning material recovers its impact resilience and maintains its cushioning properties when the pressure is released, the heat-resistant cushioning material can be used multiple times. In particular, the heat-resistant fiber cushioning material can maintain its cushioning properties by increasing the voids between the fibers, so that the heat-resistant cushioning material can be repeatedly used a plurality of times (especially 10 times or more).

[Manufacturing method according to the second embodiment]
FIG. 3 shows a schematic cross-sectional view for explaining the state before the shape fixing step in the manufacturing method according to the second embodiment. 3, the same or corresponding members as those in FIG. 1 are denoted by the same reference numerals, and description thereof is omitted. The manufacturing method according to the second embodiment basically includes the same steps as the manufacturing method according to the first embodiment, and the description of the overlapping steps will not be repeated.

As shown in FIG. 3, in the second embodiment of the present invention, according to the pressure from the heat press machine 200, the upper and lower platens 110, 120, the first and second heat-resistant cushion materials 150, 160, the first , the second metal plates 152, 162, and the first and second protective members 242, 244 heat and press the preliminary laminate 230 from both upper and lower surfaces. The pre-laminate 230 is composed of three thermoplastic liquid crystal polymer substructures 231, 232, 233 in order from the top. The thermoplastic liquid crystal polymer substructure 231 is a single thermoplastic liquid crystal polymer layer, and the thermoplastic liquid crystal polymer substructures 232 and 233 have conductive patterns formed only on the upper surfaces of the thermoplastic liquid crystal polymer layers. Therefore, the preliminary laminate 230 does not have conductor patterns on its upper and lower surfaces.

A first protective material 242 is provided above the preliminary laminate 230 , and a second protective material 244 is provided below the preliminary laminate 230 . Between the first protective member 242 and the upper platen 110, a first heat-resistant cushion member 150 is arranged on the upper platen 110 side, and a first metal plate 152 is arranged on the first protective member 242 side. is set. On the other hand, between the second protective material 244 and the lower platen 120, a second heat-resistant cushion material 160 is provided on the lower platen 120 side, and a second metal plate 162 is provided on the second protective material 244 side. is arranged.

(Shape fixing process)
The shape-fixing step is carried out in substantially the same manner as in FIG. 2, except that first and second protective members 242, 244 are used in place of the first and second protective members 142, 144 of FIG. In the second embodiment, the first and second protective members 242 and 244 respectively surround the upper and lower surfaces of the preliminary laminate 230, and the first and second protection members protrude to the sides of the preliminary laminate 230. The ends of the members 242, 244 are pressed vertically by the first and second heat-resistant cushion members 150, 160. As shown in FIG.

(Thermocompression process)
After fixing the shape of the pre-laminate 230 to the desired shape by the shape fixing step, the pressure is then reduced to a second pressure lower than the first pressure. Then, under the second pressure, the temperature of the pre-laminate 230 is raised to the thermocompression bonding temperature and held for a predetermined time, whereby the adjacent thermoplastic liquid crystal polymer substructures 231, 232, 233 are thermocompression bonded. be.

Since no conductor pattern is formed on the upper and lower surfaces of the preliminary laminate 230, even if pressure is applied from the metal plate during thermocompression bonding, the shape of the upper and lower surfaces of the preliminary laminate 230 is not affected. Crimping can be performed. In such a case, single-layer sheets may be used as the first and second protective materials 242, 244 for simplification of the manufacturing process.

In addition, when a conductor pattern is formed on at least one of the upper surface and the lower surface of the thermoplastic liquid crystal polymer multilayer structure, the protective material in contact with the surface on which the conductor pattern is formed deforms according to the shape of the conductor pattern. A multi-layer composite material is possible, and the protective material in contact with the surface on which the conductor pattern is not formed may be a single-layer sheet.

[Manufacturing method according to the third embodiment]
A method for manufacturing a thermoplastic liquid crystal polymer multilayer structure according to another embodiment of the present invention will now be described with reference to FIGS. 4 and 5. FIG. In the present invention, the protective material, the metal plate, and the heat-resistant cushioning material may be provided on at least one of the upper and lower surfaces of the preliminary laminate in this order from the surface of the preliminary laminate. 5, these are arranged on one side of the preliminary laminate. In the figure, the metal plate and the heat-resistant cushioning material are arranged only above the preliminary laminate for the sake of clarity, but naturally the metal plate and the heat-resistant cushioning material are arranged only below the preliminary laminate. You may

FIG. 4 is a schematic cross-sectional view for explaining the state before the shape fixing step in the method for manufacturing a thermoplastic liquid crystal polymer multilayer structure according to the third embodiment of the present invention, and FIG. FIG. 4 is a schematic cross-sectional view for explaining a state in which pressure is applied to the preliminary laminate; 4 and 5, the same or corresponding members as those in FIG. 1 are denoted by the same reference numerals, and description thereof is omitted. The manufacturing method according to the third embodiment basically includes the same steps as those of the manufacturing method according to the first embodiment, and descriptions of overlapping steps will not be repeated.

As shown in FIG. 4, in the third embodiment of the present invention, a heat press machine 300 having an upper platen 110 and a lower platen 120 heats and presses a preliminary laminate 130 from both upper and lower surfaces. The preliminary laminate 130 is composed of three thermoplastic liquid crystal polymer substructures 131, 132 and 133 in order from the top. The thermoplastic liquid crystal polymer substructures 131 and 132 have conductor patterns formed only on the upper surfaces, and the thermoplastic liquid crystal polymer substructure 133 has conductor patterns formed on the upper and lower surfaces. Therefore, conductor patterns are formed as conductor layers on the upper and lower surfaces of the preliminary laminate.

A first protective material 142 is provided above the preliminary laminate 130 , and a second protective material 144 is provided below the preliminary laminate 130 . Between the first protective member 142 and the upper platen 110, a first heat-resistant cushion member 150 is arranged on the upper platen 110 side, and a first metal plate 152 is arranged on the first protective member 142 side. is set. On the other hand, nothing is disposed between the second protective member 144 and the lower platen 120, and the second protective member 144 directly contacts the lower platen 120 during pressurization.

In the present invention, the protective material, the metal plate, and the heat-resistant cushioning material may be disposed on at least one of the upper and lower surfaces of the preliminary laminate in this order from the surface of the preliminary laminate. Since the heat-resistant cushioning material 150 alone can achieve a sufficient sinking property against the pressure applied by the upper and lower platens, the metal plate and the heat-resistant cushioning material are omitted on the lower platen side. .

(Shape fixing process)
As shown in FIG. 5, a heat press machine 300 having an upper platen 110 and a lower platen 120 is used to apply a first heat-resistant cushioning material 150, a first metal plate 152, and a first protective material 142 from the upper surface, and from the lower surface. The preliminary laminate 130 is sandwiched between the upper and lower surfaces of the second protective material 144, and the preliminary laminate 130 is pressurized to a first pressure so as to form a desired shape of a thermoplastic liquid crystal polymer multilayer structure. Pressurization is applied to the pre-laminate 130 for a time of . In this shape fixing step, the first heat-resistant cushion material 150 is deformed by the first pressure.

The first and second protective members 142, 144 surround the top and bottom surfaces of the preliminary laminate 130, respectively, and the first and second protective members 142, 144 protruding to the sides of the preliminary laminate 130 The ends are further pressed vertically by the first heat-resistant cushion material 150 and the lower platen 120 . In this case, the sealing structure of the first and second protective members 142 and 144 is formed by pressing the first heat-resistant cushion member 150 against the lower platen 120. As shown in FIG. With this sealing structure, the shape of the preliminary laminate 130 including the side surfaces is fixed, and the thermoplastic liquid crystal polymer of the preliminary laminate 130 can be prevented from flowing laterally under pressure in the subsequent heating step. can.

On the other hand, since the first metal plate 152 is provided, even if pressure is applied to the first heat-resistant cushioning material 150 to deform it in the shape-fixing process, the pattern derived from the heat-resistant cushioning material 150 will remain unchanged. can be prevented from being reflected on the surface of the preliminary laminate 130 .

Further, following the deformation of the first heat-resistant cushion material 150 , the first and second protective materials 142 and 144 deform so that their ends wrap around the side surfaces of the preliminary laminate 130 . As a result, the side surfaces of the preliminary laminate 130 are wrapped by the protective materials 142, 144 and the heat-resistant cushioning material 150, and the shape of the preliminary laminate 130 is fixed so that the desired thermoplastic liquid crystal polymer multilayer structure shape is obtained. can do.

The step of increasing the pressure to the first pressure may be performed at room temperature, or may be appropriately heated as long as it is lower than the thermocompression bonding temperature of the thermoplastic liquid crystal polymer. When heating, the heating may be performed before the pressure is increased.

(Thermocompression process)
After fixing the shape of the pre-laminate 130 to the desired shape by the shape fixing step, the pressure is then reduced to a second pressure lower than the first pressure. In the thermocompression bonding step, the temperature of the preliminary laminate 130 is raised to the thermocompression bonding temperature under the second pressure and held for a predetermined time, whereby the adjacent thermoplastic liquid crystal polymer substructures 131, 132, 133 are bonded together. It is thermo-compressed. During thermocompression bonding, the conductor patterns formed on the upper and lower surfaces of the preliminary laminate 130 are protected by the protective materials 142 and 144, so that the conductor patterns are not displaced even when subjected to pressure from the metal plate. It can be performed.

After the thermocompression bonding step, the temperature is lowered, the pressure is released, and then the thermoplastic liquid crystal polymer multilayer structure is removed from the protective material to obtain a thermoplastic liquid crystal polymer multilayer structure having a desired shape (laminated structure). can.

Besides the representative first, second and third embodiments described above, various embodiments can be included based on the concept of the present invention. Below, points common to each embodiment will be described.

(Heat resistant cushion material)
The heat-resistant cushioning material is not particularly limited as long as it has impact resilience while having deformability. Preferred heat-resistant cushioning materials include heat-resistant cushioning sheets, heat-resistant fiber cushioning materials, and the like.

The basis weight of the heat-resistant cushioning material can be appropriately selected according to the type of constituent material from the viewpoint of having rebound resilience while having deformability. It may be up to 3000 g/m ² , preferably 150-2500 g/m ² , more preferably 300-2000 g/m ² . Also, several sheets of these heat-resistant cushioning materials may be stacked to increase the cushioning properties.

For example, the heat-resistant fiber cushion material is a cushion material formed of a heat-resistant fiber assembly. The heat-resistant fiber assembly may be formed of, for example, heat-resistant fibers that can be used at the thermocompression bonding temperature, for example, heat-resistant fibers whose heat distortion temperature is equal to or higher than the thermocompression bonding temperature. It can be set according to the crimping temperature. For example, the heat-resistant fiber may be a fiber that can be used as a cushioning material at 260°C.

Heat-resistant fibers include heat-resistant organic fibers, metal fibers, and inorganic fibers. More specifically, the heat-resistant organic fiber may be a fiber having a melting point or thermal decomposition temperature of 260 ° C. or higher, such as aramid fiber (meta-aramid fiber, para-aramid fiber), semi-aromatic polyamide fiber (for example, polyamide (PA9C) fiber composed of _C9 aliphatic diamine units and aromatic dicarboxylic acid units), polyimide (PI) fiber, polyphenylene sulfide (PPS) fiber, polyetheretherketone (PEEK) fiber , polybenzimidazole (PBI) fiber, polyparaphenylenebenzoxazole (PBO) fiber, novoloid fiber, and the like. Metal fibers include stainless steel fibers, copper fibers, nickel fibers, aluminum fibers, and the like. Examples of inorganic fibers include glass fibers. These fibers may be used singly or in combination of two or more as fibers constituting the heat-resistant fiber cushioning material.

The fiber assembly is not particularly limited as long as it is a fiber assembly exhibiting cushioning properties, and may be a woven fabric, a knitted fabric, a mechanically bonded nonwoven fabric (e.g., needle-punched nonwoven fabric, etc.), a felt, a web, or the like. From the viewpoint of , nonwoven fabrics, felt, plate-like moldings of metal fibers and inorganic fibers are preferable, and metal fiber nonwoven fabrics or organic fiber nonwoven fabrics having a melting point or thermal decomposition temperature of 260° C. or higher are more preferable.

The fiber diameter of the heat-resistant fiber cushion material may be, for example, 1-30 μm, preferably 2-20 μm, and more preferably 5-18 μm.

Also, the heat-resistant cushion sheet is a cushion material formed of a heat-resistant material other than fibers. Heat-resistant materials other than fibers include heat-resistant resins and heat-resistant rubbers. Examples of heat-resistant cushion sheets include heat-resistant cushion sheets having a Shore hardness of about A50 to A95, such as "Super Tempex" manufactured by Seibu Polymer Kasei Co., Ltd. and "Silbest" manufactured by Kinyo Co., Ltd.

According to the manufacturing process of the present invention, the heat-resistant cushioning material can be used repeatedly, and the manufacturing cost can be reduced.

In addition, the vertical length (C _L ) and the horizontal side length (C _W ) of the heat-resistant cushioning material are equal to the vertical length (P _L ) and the horizontal side length of the preliminary laminate. It is preferable to have the following relation to the height (P _W ).
P _L +1 ≤ C _L ≤ P _L +10 (unit: cm) and P _W +1 ≤ C _W ≤ P _W +10 (unit: cm)
More preferably, it has the following relationship.
P _L +2 ≤ C _L ≤ P _L +8 (unit: cm) and P _W +2 ≤ C _W ≤ P _W +8 (unit: cm)

The heat-resistant cushioning material may have a thickness of, for example, about 0.5 to 20 mm, preferably about 1 to 18 mm, more preferably about 1.5 to 16 mm.

In addition, when the total thickness of the preliminary laminate laminated by hot pressing after lamination is D (unit: mm), the thickness of the heat-resistant cushioning material is (D + 0.5) ~ as the total thickness in the hot press. It may be about (D+20) mm, preferably about (D+1) to (D+15) mm, more preferably about (D+2) to (D+10) mm.

(metal plate)
The metal plate is provided to prevent the shape derived from the heat-resistant cushion material from being reflected on the surface of the thermoplastic liquid crystal polymer multilayer structure. Therefore, when the heat-resistant cushioning material is not provided, the metal plate does not have to be provided either.
As the metal constituting the metal plate, for example, a known or commonly used metal material having high compression resistance can be used, preferably stainless steel or copper.

The metal plate may have a thickness of, for example, about 0.1 to 2 mm, preferably about 0.2 to 0.8 mm, more preferably about 0.3 to 0.6 mm.

In addition, the vertical length (M _L ) and horizontal side length (M _W ) of the metal plate are equal to the vertical length (C _L ) and horizontal side length of the heat-resistant cushioning material. (C _W ) and the longitudinal length (P _L ) and lateral side length (P _W ) of the pre-laminate may have the following relationships.
P _L −1.0≦M _L ≦P _L (unit: cm)
P _W −1.0≦M _W ≦P _W (Unit: cm)
C _L -11 ≤ M _L ≤ C _L -1.2 (unit: cm) and C _W -11 ≤ M _W ≤ C _W -1.2 (unit: cm)

Preferably, it may have the following relationships.
P _L −0.8≦M _L ≦P _L (unit: cm)
P _W −0.8≦M _W ≦P _W (Unit: cm)
C _L -8 ≤ M _L ≤ C _L -0.5 (unit: cm) and C _W -8 ≤ M _W ≤ C _W -0.5 (unit: cm)

(Protective layer)
The protective material is used to protect the surface of the pre-laminate by wrapping the surface of the pre-laminate, that is, the upper and lower surfaces and the side surfaces, in the thermocompression bonding process. Examples of protective materials include polytetrafluoroethylene sheets, polyimide sheets, and composites of metal foils such as aluminum foils and heat-resistant polymer sheets.

For example, the protective material may be properly used depending on the condition of the surface of the preliminary laminate. It may be a multi-layer composite material that can be deformed according to the shape of the conductor pattern.

On the other hand, when a conductor pattern is formed on the outermost surface of the preliminary laminate, the protective material in contact with the outermost surface may be a multilayer composite material that can be deformed according to the shape of the conductor pattern. A simple single layer sheet may be used for ease of work.

For example, the multilayer composite includes a first metal foil (preferably aluminum foil), a pair of high-density polyethylene sheets with their MD directions perpendicular to each other, a second metal foil (preferably aluminum foil), and a low Multilayer composites formed of friction films are particularly preferred.

A known or commonly used HDPE sheet can be used as the high-density polyethylene sheet. It may be up to about 200,000.

Examples of low-friction films include films having a low static friction coefficient of 0.30 or less (preferably about 0.05 to 0.25) as defined in JIS K 7125. Specifically, Examples include ultra-high molecular weight polyethylene films and polytetrafluoroethylene films.

For example, the ultra-high molecular weight polyethylene film has a coefficient of static friction of about 0.10 to 0.25 and a viscosity average molecular weight of, for example, 1 million or more, preferably about 2 million to 7 million, more preferably 3 million to 600. It may be about 10,000. The intrinsic viscosity used to calculate the viscosity average molecular weight can be measured according to JIS K7367-3:1999.

The polytetrafluoroethylene film has a coefficient of static friction of about 0.08 to 0.12, and a melt viscosity at 380° C. of 10 ¹⁰ poise or more, preferably in the range of 10 ¹⁰ to 10 ¹¹ poise. may

(Thermoplastic liquid crystal polymer multilayer structure)
In the production method of the present invention, it is possible to prevent the polymer from flowing and crushing the conductor pattern in the thermocompression bonding process, prevent unintended displacement between layers, and achieve excellent integrity between the thermoplastic liquid crystal polymer substructures. A thermoplastic liquid crystal polymer multilayer structure can be obtained.

As the thermoplastic liquid crystal polymer substructure, various shapes can be used as long as they are formed from a thermoplastic liquid crystal polymer and a plurality of thermoplastic liquid crystal polymer substructures can be integrated by thermocompression bonding. Preferably, in the thermoplastic liquid crystal polymer multilayer structure, the thermoplastic liquid crystal polymer substructure comprises (i) a thermoplastic liquid crystal polymer layer alone (L), (ii) a thermoplastic liquid crystal polymer layer having a conductor layer on one side ( CL), and (iii) a thermoplastic liquid crystal polymer layer (CLC) with conductor layers on both sides. Here, the conductor layer includes a conductor pattern, a conductor foil, a conductor film, and the like, and these conductor layers may be appropriately formed in a desired shape as necessary.

The thermoplastic liquid crystal polymer multilayer structure may have three or more conductor layers. In addition, it may have 5 or more conductor layers, or 7 or more conductor layers, depending on the application. The upper limit of the number of conductor layers can be appropriately set according to the application, and may be, for example, about 20 layers.

Further, the thermoplastic liquid crystal polymer films constituting the thermoplastic liquid crystal polymer multilayer structure may have the same or different melting points. When different, the temperature difference between the film with the lowest melting point and the film with the highest melting point is greater than 0°C and 100°C or less, preferably 10°C or more and 90°C or less, more preferably 20°C or more. It may be 80° C. or lower.

Further, the thermoplastic liquid crystal polymer films constituting the thermoplastic liquid crystal polymer multilayer structure may have the same thickness or different thicknesses. If different, the difference between the thickest and thinnest films may be greater than 0 μm and less than or equal to 50 μm, preferably greater than or equal to 10 μm and less than or equal to 40 μm, more preferably greater than or equal to 20 μm and less than or equal to 30 μm.

The method of manufacturing the thermoplastic liquid crystal polymer multilayer structure may optionally include processing steps known to those skilled in the art, such as blind vias, drilling for through holes and plating.

For example, the thermoplastic liquid crystal polymer multilayer structure can be effectively used as a component used in the electric/electronic field, office equipment/precision equipment field, and the like. It can be usefully used as

EXAMPLES The present invention will be described in more detail below with reference to Examples, but the present invention is not limited to these Examples. In addition, in the following examples and comparative examples, various physical properties were measured by the following methods.

[Melting point]
Using DSC (manufactured by TA Instruments, "Q2000"), 5 mg of the sample was heated from room temperature to the temperature at which the sample was polymerized at a rate of 20 ° C. per minute, maintained at that temperature for 2 minutes, and It was cooled to 25°C at a rate of 20°C, held at 25°C for 2 minutes, and then heated again at a rate of 20°C per minute.

[Transfer of pattern to thermoplastic liquid crystal polymer multilayer structure (LCP multilayer structure)]
The surface of the thermoplastic liquid crystal polymer multilayer structure obtained after the thermocompression bonding process was visually checked to see if the pattern of the heat-resistant cushioning material had been transferred, and evaluated according to the following criteria.
◯: No transferred pattern was observed on the surface of the thermoplastic liquid crystal polymer multilayer structure.
x: A transferred pattern was confirmed on the surface of the thermoplastic liquid crystal polymer multilayer structure.

[Shape retention of cushion material]
The shape retainability of the heat-resistant cushion material after the thermocompression bonding process was evaluated according to the following criteria.
◯: The heat-resistant cushioning material retained its shape and was not fused to the platen, and the cushioning property was restored after the pressure was released.
x: The heat-resistant cushioning material could not retain its shape and was fused to the platen, and/or did not recover its cushioning properties after the pressure was released.

[Flow and Collapse of Thermoplastic Liquid Crystal Polymer Multilayer Structure (LCP Multilayer Structure)]
The flow and collapse of the thermoplastic liquid crystal polymer multilayer structure obtained after the thermocompression bonding process were visually evaluated according to the following criteria.
◯: The thermoplastic liquid crystal polymer multilayer structure was adhered without shifting in each layer, the conductor pattern on the surface was not crushed, and the resin did not flow laterally on the side surface.
×: In the thermoplastic liquid crystal polymer multilayer structure, at least one of the following phenomena occurs: each layer is adhered in a shifted state, the conductor pattern on the surface is crushed, or the resin flows laterally even on the side surface. one had occurred.

(Reference example 1)
A thermoplastic liquid crystal polymer film (manufactured by Kuraray Co., Ltd., "Vecstar", 30 cm long × 40 cm wide × 18 µm thick) with a melting point of 310 ° C. was coated with copper foil of the same size (manufactured by Fukuda Metal Foil & Powder Co., Ltd., "CF-H9A-DS-HD2-12") were superimposed and thermocompression bonded at 290 ° C. and 2 MPa by a vacuum batch press (manufactured by Kitagawa Seiki Co., Ltd., "VH2-1600") to produce a double-sided copper-clad board. . A conductor pattern was then formed by etching to obtain a thermoplastic liquid crystal polymer substructure with conductor patterns formed on both sides.

(Reference example 2)
A thermoplastic liquid crystal polymer film with a melting point of 310° C. (manufactured by Kuraray Co., Ltd., “Vecstar”, length 30 cm×width 40 cm×thickness 18 μm) was coated with copper foil of the same size (manufactured by Fukuda Metal Foil & Powder Co., Ltd., "CF-H9A-DS-HD2-12") are superimposed and thermocompressed at 290 ° C. and 2 MPa by a vacuum batch press (manufactured by Kitagawa Seiki Co., Ltd., "VH2-1600") to produce a single-sided copper-clad board. bottom. A conductor pattern was then formed by etching to obtain a thermoplastic liquid crystal polymer substructure with a conductor pattern formed on one side.

[Example 1]
In the heat press, as shown in FIG. 1, a heat-resistant cushioning material, a metal plate, and a protective material are arranged in order from the upper platen of the heat press, and a heat-resistant cushioning material is provided in order from the lower platen of the heat press. , a metal plate, and a protective material were disposed, and the pre-laminate was aligned and arranged between these protective materials. The preliminary laminate is composed of three sheets of thermoplastic liquid crystal polymer substructures by combining the thermoplastic liquid crystal polymer substructures obtained in Reference Examples 1 and 2 as shown in FIG. , the protective material, and the pre-laminate have the same central point in the thickness direction.

As the heat-resistant cushioning material, a stainless steel web (manufactured by Nippon Seisen Co., Ltd., "Naslon Web", fiber diameter 8 μm, basis weight 1800 g/m ² , length 33 cm × width 43 cm × thickness 15 mm) was used. A SUS plate (length 30 cm x width 40 cm x thickness 0.4 mm) was used as the plate. Furthermore, as protective materials, a polytetrafluoroethylene film (thickness: 30 μm, static friction coefficient: 0.12), a first aluminum foil (thickness: 50 μm), a first high-density polyethylene film (Okura Kogyo Co., Ltd., "HD film", thickness 50 μm), the second high-density polyethylene film in a state in which the MD direction is perpendicular to the first high-density polyethylene film (manufactured by Okura Kogyo Co., Ltd., "HD film" , thickness 50 μm, melt flow index 0.05), and a second aluminum foil (thickness 50 μm). The size of the protective material is 34 cm long×44 cm wide.

A vacuum batch press (“VH2-1600” manufactured by Kitagawa Seiki Co., Ltd.) was used as a heat press, and a shape fixing step was first performed. Specifically, in a vacuum of 4 torr and 160° C., the upper and lower surfaces of the preliminary laminate were pressed at a pressure of 4 MPa for 10 minutes. As a result of this operation, as shown in FIG. 2, the side surfaces of the preliminary laminate were wrapped by the protective material and the heat-resistant cushioning material, and the protective material was sealed by the heat-resistant cushioning material on the sides of the preliminary laminate.
Next, the pressure applied to the preliminary laminate is reduced to 2 MPa, the temperature is raised to 300° C., the temperature is maintained for 30 minutes, the preliminary laminate is thermally compressed, and the pressure is released after cooling to room temperature. A thermoplastic liquid crystal polymer multilayer structure was obtained. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Example 2]
As the heat-resistant cushioning material, stainless steel felt (manufactured by Nippon Seisen Co., Ltd., "Naslon Felt", fiber diameter 8 μm, basis weight 1500 g/m ² , length 33 cm × width 43 cm × thickness 7 mm) is used. A thermoplastic liquid crystal polymer multilayer structure was obtained in the same manner as in Example 1. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Example 3]
Example 1 except that a para-aramid fiber needle-punched nonwoven fabric (manufactured by Ichikawa Co., Ltd., "Ace Board", basis weight 1300 g/m ² , length 33 cm × width 43 cm × thickness 7 mm) is used as the heat-resistant cushioning material. A thermoplastic liquid crystal polymer multilayer structure was obtained in the same manner as above. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Example 4]
As a heat-resistant cushioning material, a melt-blown nonwoven fabric (basis weight: 800 g/m ² , length: 33 cm) made of a semi-aromatic polyamide resin composed of _C9 aliphatic diamine units and terephthalic acid units (manufactured by Kuraray Co., Ltd., “Genestar PA9T”) A thermoplastic liquid crystal polymer multi-layer structure was obtained in the same manner as in Example 1, except that 43 cm in width and 3 mm in thickness were used. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Comparative Example 1]
A thermoplastic liquid crystal polymer multilayer structure was prepared in the same manner as in Example 1, except that non-heat-resistant polyester nonwoven fabric (basis weight: 4400 g/m ² , length: 33 cm x width: 43 cm x thickness: 20 mm) was used as the cushioning material. Obtained. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Example 5]
A thermoplastic liquid crystal polymer film having a melting point of 310° C. (manufactured by Kuraray Co., Ltd., “Vecstar”, length 30 cm×width 40 cm×thickness 18 μm) and the thermoplastic liquid crystal polymer substructure obtained in Reference Example 2 are shown in FIG. to form a prelaminate with three thermoplastic liquid crystal polymer substructures.

A thermoplastic liquid crystal polymer multilayer structure was obtained in the same manner as in Example 1, except that a polytetrafluoroethylene sheet was used as a protective material for this preliminary laminate. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Example 6]
As the heat-resistant cushioning material, stainless steel felt (manufactured by Nippon Seisen Co., Ltd., "Naslon Felt", fiber diameter 8 μm, basis weight 1500 g/m ² , length 33 cm × width 43 cm × thickness 7 mm) is used. A thermoplastic liquid crystal polymer multilayer structure was obtained in the same manner as in Example 5. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Example 7]
Example 5 except that a para-aramid fiber needle-punched nonwoven fabric ("Ace Board" manufactured by Ichikawa Co., Ltd., basis weight 1300 g/m ² , length 33 cm × width 43 cm × thickness 7 mm) is used as the heat-resistant cushioning material. A thermoplastic liquid crystal polymer multilayer structure was obtained in the same manner as above. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Example 8]
As a heat-resistant cushioning material, a melt-blown nonwoven fabric (basis weight: 800 g/m ² , length: 33 cm) made of a semi-aromatic polyamide resin composed of _C9 aliphatic diamine units and terephthalic acid units (manufactured by Kuraray Co., Ltd., “Genestar PA9T”) A thermoplastic liquid crystal polymer multi-layer structure was obtained in the same manner as in Example 5, except that 43 cm in width and 3 mm in thickness were used. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Comparative Example 2]
A thermoplastic liquid crystal polymer multilayer structure was prepared in the same manner as in Example 5, except that non-heat-resistant polyester nonwoven fabric (basis weight: 4400 g/m ² , length: 33 cm x width: 43 cm x thickness: 20 mm) was used as the cushioning material. Obtained. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Example 9]
In the heat press, as shown in FIG. 4, a heat-resistant cushioning material, a metal plate, and a protective material are arranged in order from the upper platen of the heat press, and between the lower platen of the heat press and the preliminary laminate, A thermoplastic liquid crystal polymer multilayer structure was obtained in the same manner as in Example 1, except that only the protective material was provided. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Example 10]
As the heat-resistant cushioning material, stainless steel felt (manufactured by Nippon Seisen Co., Ltd., "Naslon Felt", fiber diameter 8 μm, basis weight 1500 g/m ² , length 33 cm × width 43 cm × thickness 7 mm) is used. A thermoplastic liquid crystal polymer multilayer structure was obtained in the same manner as in Example 9. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Example 11]
Example 9 except that a para-aramid fiber needle-punched nonwoven fabric ("Ace Board" manufactured by Ichikawa Co., Ltd., basis weight 1300 g/m ² , length 33 cm × width 43 cm × thickness 7 mm) is used as the heat-resistant cushioning material. A thermoplastic liquid crystal polymer multilayer structure was obtained in the same manner as above. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Example 12]
As a heat-resistant cushioning material, a melt-blown nonwoven fabric (basis weight 800 g/ ^{m 2} _, length 33 cm x width A thermoplastic liquid crystal polymer multilayer structure was obtained in the same manner as in Example 9, except for using a 43 cm x 3 mm thick. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Example 13]
The thermoplastic liquid crystal polymer substructures obtained in Reference Examples 1 and 2 were degassed and dried in a hot air oven at 200°C for 60 minutes to reduce the moisture content to 100 ppm or less. A thermoplastic liquid crystal polymer multilayer structure was obtained in the same manner as in Example 9, except that the steps were performed. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.
In addition, the thermoplastic liquid crystal polymer multilayer structure obtained through the degassing and drying step had high adhesion between the respective layers, and it was difficult to separate the adjacent thermoplastic liquid crystal polymer substructures.

[Example 14]
The thermoplastic liquid crystal polymer substructures obtained in Reference Examples 1 and 2 were degassed and dried in a vacuum oven at 200° C. and a degree of vacuum of 1500 Pa or less for 60 minutes to reduce the moisture content to 100 ppm or less. A thermoplastic liquid crystal polymer multilayer structure was obtained in the same manner as in Example 9, except that the shape fixing step was performed. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.
In addition, the thermoplastic liquid crystal polymer multilayer structure obtained through the degassing and drying step had high adhesion between the respective layers, and it was difficult to separate the adjacent thermoplastic liquid crystal polymer substructures.

[Comparative Example 3]
A thermoplastic liquid crystal polymer multilayer structure was prepared in the same manner as in Example 9, except that non-heat-resistant polyester nonwoven fabric (basis weight: 4400 g/m ² , length: 33 cm x width: 43 cm x thickness: 20 mm) was used as the cushioning material. Obtained. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Comparative Example 4]
In a hot press machine 400, as shown in FIG. 6, a heat-resistant cushion material 150 and a protective material 142 are arranged in this order from the upper platen 110 of the hot press machine without using a metal plate. A thermoplastic liquid crystal polymer multilayer structure was obtained in the same manner as in Example 1 except that the heat-resistant cushioning material 160 and the protective material 144 were arranged in order from the platen. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Comparative Example 5]
As the heat-resistant cushioning material, stainless steel felt (manufactured by Nippon Seisen Co., Ltd., "Naslon Felt", fiber diameter 8 μm, basis weight 1500 g/m ² , length 33 cm × width 43 cm × thickness 7 mm) is used. A thermoplastic liquid crystal polymer multilayer structure was obtained in the same manner as in Comparative Example 4. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Comparative Example 6]
Comparative Example 4 except that para-aramid fiber needle-punched nonwoven fabric ("Ace Board" manufactured by Ichikawa Co., Ltd., basis weight 1300 g/m ² , length 33 cm × width 43 cm × thickness 7 mm) is used as the heat-resistant cushioning material. A thermoplastic liquid crystal polymer multilayer structure was obtained in the same manner as above. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Comparative Example 7]
As a heat-resistant cushioning material, a melt-blown nonwoven fabric (basis weight: 800 g/m ² , length: 33 cm) made of a semi-aromatic polyamide resin composed of _C9 aliphatic diamine units and terephthalic acid units (manufactured by Kuraray Co., Ltd., “Genestar PA9T”) A thermoplastic liquid crystal polymer multi-layer structure was obtained in the same manner as in Comparative Example 4, except that 43 cm in width and 3 mm in thickness were used. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Comparative Example 8]
A thermoplastic liquid crystal polymer multilayer structure was prepared in the same manner as in Comparative Example 4, except that non-heat-resistant polyester nonwoven fabric (basis weight: 4400 g/m ² , length: 33 cm x width: 43 cm x thickness: 20 mm) was used as the cushioning material. Obtained. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Comparative Example 9]
In the heat press machine 500, as shown in FIG. 7, heat was applied in the same manner as in Example 1, except that the size of the metal plate was increased and a SUS plate (length 31 cm x width 41 cm x thickness 0.4 mm) was used. A heat-resistant cushioning material 150, a metal plate 552, and a protective material 142 are arranged in order from the upper platen 110 of the press machine 500, and a heat-resistant cushioning material 160, a metal plate 562, and a protective material are arranged in order from the lower platen of the heat press machine. A thermoplastic liquid crystal polymer multilayer structure was obtained except that No. 144 was disposed. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Comparative Example 10]
As the heat-resistant cushioning material, stainless steel felt (manufactured by Nippon Seisen Co., Ltd., "Naslon Felt", fiber diameter 8 μm, basis weight 1500 g/m ² , length 33 cm × width 43 cm × thickness 7 mm) is used. A thermoplastic liquid crystal polymer multilayer structure was obtained in the same manner as in Comparative Example 9. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Comparative Example 11]
Comparative Example 9 except that para-aramid fiber needle-punched nonwoven fabric ("Ace Board" manufactured by Ichikawa Co., Ltd., basis weight 1300 g/m ² , length 33 cm × width 43 cm × thickness 7 mm) is used as the heat-resistant cushioning material. A thermoplastic liquid crystal polymer multilayer structure was obtained in the same manner as above. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Comparative Example 12]
As a heat-resistant cushioning material, a melt-blown nonwoven fabric (basis weight: 800 g/m ² , length: 33 cm) made of a semi-aromatic polyamide resin composed of _C9 aliphatic diamine units and terephthalic acid units (manufactured by Kuraray Co., Ltd., “Genestar PA9T”) A thermoplastic liquid crystal polymer multi-layer structure was obtained in the same manner as in Comparative Example 9, except that 43 cm in width and 3 mm in thickness were used. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Comparative Example 13]
A thermoplastic liquid crystal polymer multilayer structure was prepared in the same manner as in Comparative Example 9, except that non-heat-resistant polyester nonwoven fabric (basis weight: 4400 g/m ² , length: 33 cm x width: 43 cm x thickness: 20 mm) was used as the cushioning material. Obtained. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

In Examples 1 to 8, the heat-resistant cushioning material was combined with the metal plate, and thermocompression bonding was performed with the protective material in contact with the side surface of the preliminary laminate. The pattern derived from the cushioning material was not transferred, and neither the flow of the thermoplastic liquid crystal polymer nor the crushing of the conductor pattern was confirmed. Also, the heat-resistant cushioning material was able to retain its shape in the thermocompression bonding process, and no fusion to the platen occurred. Moreover, after releasing the pressure, the cushioning property was recovered again. Therefore, the heat-resistant cushioning material is presumed to withstand repeated use.

Further, even in Examples 9 to 14 in which the heat-resistant cushioning material is provided only on one side of the preliminary laminate, the obtained thermoplastic liquid crystal polymer multilayer structure has a heat-resistant fiber cushioning material. No pattern was transferred, and neither flow of the thermoplastic liquid crystal polymer nor crushing of the conductor pattern was confirmed. Also, the heat-resistant cushioning material was able to retain its shape in the thermocompression bonding process, and no fusion to the platen occurred. Moreover, after releasing the pressure, the cushioning property was recovered again.

On the other hand, in Comparative Examples 1 to 3, 8 and 13, since polyester nonwoven fabric with low heat resistance was used as the cushioning material, the obtained thermoplastic liquid crystal polymer multilayer structure did not have transfer originating from the polyester nonwoven fabric, The thermocompression bonding temperature above the melting point of the polyester resin (melting point: less than 260° C.) used in the nonwoven fabric causes the polyester to melt, making it impossible to sufficiently stop the flow of the liquid crystal polymer, making it impractical. Moreover, since the polyester resin is melted, the thermoplastic liquid crystal polymer multilayer structure is severely displaced, and many layers cannot be stacked.

In Comparative Examples 4 to 7, since the heat-resistant cushioning material was used without being combined with the metal plate, the flow of the thermoplastic liquid crystal polymer and the crushing of the conductor pattern were not confirmed, but the pattern derived from the heat-resistant fiber cushioning material was observed. , has been transferred to the surface of the thermoplastic liquid crystal polymer multilayer structure.

In Comparative Examples 9 to 13, the size of the metal plate was larger than that of the preliminary laminate, and the protective material was thermocompressed in a state where the corners of the preliminary laminate could not come into contact with the side surface of the preliminary laminate. The pressure increased at the edge of the body, and regardless of which cushioning material was used, the pressure became uneven and the resin flowed at the edge.

According to the production method of the present invention, a thermoplastic liquid crystal polymer multilayer structure can be efficiently produced, and the obtained thermoplastic liquid crystal polymer multilayer structure can be used in the fields of electrical and electronic, office equipment, precision equipment, etc. It can be effectively used as a part used in a circuit board, for example, a circuit board (especially a millimeter wave radar board).

As described above, preferred embodiments of the present invention have been described, but various additions, changes, or deletions are possible without departing from the spirit of the present invention, and such are also included within the scope of the present invention. be

100, 200, 300, 400, 500... Hot press machine 110... Upper platen 120... Lower platen 130, 230... Preliminary laminates 131, 132, 133, 231, 232, 233... Thermoplastic liquid crystal polymer substructures 142, 242... First protective materials 144, 244 Second protective material 150 First heat-resistant cushioning material 152 First metal plate 160 Second heat-resistant cushioning material 162 Second metal plate

Claims (7)

(i) a thermoplastic liquid crystal polymer film, (ii) a thermoplastic liquid crystal polymer film having a conductor layer on one side, and (iii) a thermoplastic liquid crystal polymer film having a conductor layer on both sides. A pre-laminate in which at least two thermoplastic liquid crystal polymer substructures are superimposed is heated and pressed in a hot press through protective materials provided on the upper and lower surfaces of the laminate to produce a thermoplastic liquid crystal polymer multilayer structure. a method,
A heat-resistant cushion material and a metal plate are arranged in order from the heat press side on at least one of the upper and lower surfaces of the preliminary laminate,
The heat press is pressurized to a first pressure below the thermocompression bonding temperature of the thermoplastic liquid crystal polymer, and (I) the preliminary laminate is pressed by the heat-resistant cushion material and the metal plate through the protective material. , (II) on the side of the pre-laminate, the end of the protective material is sealed by the pressure of the heat-resistant cushioning material, and (III) the protective material is in contact with all the side surfaces of the pre-laminate. a shape fixing step of fixing the shape of the preliminary laminate so that the preliminary laminate has a desired shape of a thermoplastic liquid crystal polymer multilayer structure by wrapping the preliminary laminate in a state;
The pressure is reduced from the first pressure, and the temperature is raised to a thermocompression bonding temperature under a second pressure lower than the first pressure by 0.8 to 2.5 MPa to thermocompress the adjacent thermoplastic liquid crystal polymer substructures. a thermocompression bonding process;
A method for manufacturing a thermoplastic liquid crystal polymer multilayer structure, comprising: 2. The manufacturing method according to claim 1, wherein the conductor layer is selected from the group consisting of a conductor pattern, a conductor foil, and a conductor film,
When a conductor pattern is formed on at least one of the upper surface and the lower surface of the thermoplastic liquid crystal polymer multilayer structure,
The protective material in contact with the surface on which the conductor pattern is formed is a multilayer composite material deformable according to the shape of the conductor pattern,
The manufacturing method, wherein the protective material in contact with the surface on which the conductor pattern is not formed is a single-layer sheet. 3. The manufacturing method of claim 2, wherein the multi-layer composite comprises a first metal foil, a pair of high density polyethylene sheets perpendicular to each other in the MD direction, a second metal foil and a low friction film. Formed, manufacturing method. The manufacturing method according to any one of claims 1 to 3, wherein the heat-resistant cushioning material is a heat-resistant fiber cushioning material. 5. The manufacturing method according to claim 4, wherein the heat-resistant fiber cushion material is a metal fiber nonwoven fabric or an organic fiber nonwoven fabric having a melting point or thermal decomposition temperature of 260[deg.] C. or higher. The manufacturing method according to any one of claims 1 to 5 , wherein the longitudinal length (C _L ) and the lateral side length (C _W ) of the heat-resistant cushioning material are pre-laminated A manufacturing method having the following relationship for the longitudinal length (P _L ) and the lateral side length (P _W ) of the body.
P _L +1 ≤ C _L ≤ P _L +10 (unit: cm) and P _W +1 ≤ C _W ≤ P _W +10 (unit: cm) The manufacturing method according to any one of claims 1 to 6 , wherein the vertical length (M _L ) and the horizontal side length (M _W ) of the metal plate are equal to the heat-resistant cushion longitudinal length (C _L ) and lateral side length (C _W ) of the timber and longitudinal length (P _L ) and lateral side length (P _W ) of said pre-laminate; , having the following relationship:
P _L −1.0≦M _L ≦P _L (unit: cm)
P _W −1.0≦M _W ≦P _W (Unit: cm)
C _L -11 ≤ M _L ≤ C _L -1.2 (unit: cm) and C _W -11 ≤ M _W ≤ C _W -1.2 (unit: cm)

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