KR102306718B1 - Prepreg - Google Patents

Abstract

The present invention relates to a prepreg, the prepreg according to the present invention comprises a core material;
a first resin material laminated on the core material; and a second resin material laminated under the core material, wherein a bonding interface between the first resin material and the second resin material is located within a thickness range of the core material, and the first and second resin materials are photoinitiators or curing agents. Including an accelerator, the first resin material is characterized in that the content and curing degree or hardness of the photoinitiator or the curing accelerator is higher than that of the second resin material.

Description

prepreg {PREPREG}

The present invention relates to prepregs.

With the development of manufacturing technology for electronic devices, printed circuit boards that are essential to electronic devices are also required to be reduced in weight, thinned, and miniaturized. In a printed circuit board, wiring layers for circuit connection and insulating layers serving as interlayer insulation are alternately stacked. The wiring layer is mainly formed of a metal material such as copper, and the insulation layer is formed of a polymer resin such as resin or epoxy.

In this case, the printed circuit board should keep the thickness of the insulating layer thin in order to reduce the thickness, but as the thickness of the insulating layer decreases, it is difficult to control the characteristics of the warpage. That is, electrical, thermal, and mechanical properties are lowered because it is difficult to control the characteristics of the insulating layer with a low coefficient of thermal expansion (Low CTE), high glass transition temperature (High Tg) and high modulus compared to the wiring layer made of metal. do.

In addition, in the printed circuit board on which a plurality of electronic components are mounted, an insulating layer is stacked in multiple layers for various wiring designs. is being demanded

In general, a prepreg is configured in a plate shape in which an organic material such as epoxy is impregnated into a core material made of a woven glass cloth or fabric cloth.

Such a prepreg is applied to the central core of a multilayer printed circuit board, including the insulating layer of a copper clad laminate (CCL), or is employed as an outermost insulating layer of a multilayer printed circuit board, to improve the physical properties of the printed circuit board or to prevent warpage and to reduce the size of the printed circuit board. gives stability.

Unexamined Patent Publication No. 2010-0023978

An object of the present invention is to provide a prepreg having a thin thickness, a small unevenness in surface roughness, and excellent surface flatness.

The above object of the present invention is composed of a core material impregnated with an upper resin material and a lower resin material, the bonding interface between the upper resin material and the lower resin material is located within the thickness range of the core material, and the degree of cure or hardness of the upper resin material (modulus) is achieved by providing a prepreg that is higher than the underlying resin material.

The difference in curing degree or hardness between the upper resin material and the lower resin material is controlled by the content of the photoinitiator or curing accelerator contained in each resin material, and the upper resin material has a higher content of the photoinitiator or curing accelerator than the lower resin material.

Accordingly, under the same light or thermal conditions during the prepreg manufacturing process, the curing rate of the upper resin material is controlled relatively faster than the curing rate of the lower resin material, so that the degree of curing or hardness of the upper resin material is higher than that of the lower resin material. As a result, it is possible to control so that the surface of the upper resin material does not follow the curved portion of the surface of the core material, thereby ensuring the surface flatness of the upper surface of the upper resin material.

The prepreg according to the present invention realizes a relatively high degree of hardening or hardness of the upper part of the two types of resin materials impregnated in the core material, thereby controlling the degree of impregnation of the upper part to be relatively low, so that the unevenness of the surface roughness is small and the surface flatness is small. great.

1 is a cross-sectional view of a prepreg according to a first embodiment of the present invention.
2 is a cross-sectional view of a prepreg according to a second embodiment of the present invention.
3 is a cross-sectional view of a prepreg according to a third embodiment of the present invention.
4 to 6 are process diagrams showing a prepreg manufacturing method according to a first embodiment of the present invention,
4 is a cross-sectional view of the first resin material, the second resin material and the core material,
5 is a cross-sectional view in which the first and second resin materials are laminated on the upper and lower portions of the core material;
6 is a cross-sectional view of a prepreg in which a core material is impregnated with first and second resin materials.
7 and 8 are each a process diagram for a method of manufacturing a prepreg according to a second embodiment and a third embodiment of the present invention,
7 is a process diagram in which the second resin material laminated on the core material is formed thinner than the first resin material;
8 is a process diagram in which a first resin material laminated on a core material is formed thinner than a second resin material.

The terminology used herein is used to describe specific embodiments, not to limit the present invention. The singular form as used herein may include the plural form unless the context clearly dictates otherwise. Also, "comprise" and/or "comprising" when used herein excludes the presence or addition of the recited shapes, numbers, steps, actions, members, elements and/or groups. not to do

The objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments taken in conjunction with the accompanying drawings. In the present specification, in adding reference numbers to the components of each drawing, it should be noted that only the same components are given the same number as possible even though they are indicated on different drawings. In addition, in describing the present invention, if it is determined that a detailed description of a related known technology may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted. In this specification, terms such as first, second, etc. are used to distinguish one component from another, and the component is not limited by the terms.

Hereinafter, a prepreg (PPG) and a manufacturing method thereof according to the present invention will be described in detail with reference to FIGS. 1 to 8 .

1 is a cross-sectional view of a prepreg according to an embodiment of the present invention.

As shown, the prepreg 100 of this embodiment has a first resin material 120 and a second resin material 130 stacked up and down, and a first resin material 120 and a second resin material 130 . ) is composed of an impregnated core 110 . In this case, the substrate 140 made of a metal foil or an insulating film may be further laminated on the exposed surfaces of the first and second resin materials 120 and 130 .

The core material 110 may be composed of either a fabric cloth or a glass cloth, which has a structure in which fiberized fabric or glass filaments cross each other and are woven and are woven in 1 to 3 rows to form a resin material. strength is given compared to Accordingly, the occurrence of warpage of the prepreg when heat and pressure are applied during lamination of the resin material may be minimized.

In the core material 110 , the bent portion 111 is formed according to an arrangement in which the fabric or glass filaments are orthogonal to each other in vertical and horizontal directions. The height of the bent portion 111 may vary depending on the number of arrays of fabric or glass filaments, and in general, as the number of arrays increases, the height of the bent portion 111 may increase. That is, a position at which the fabric or glass filaments are orthogonal to each other is convex, and other portions may be formed to be relatively concave.

The core material 110 is impregnated with the first resin material 120 and the second resin material 130 , which includes the core material 110 interposed between the prepared first resin material 120 and the second resin material 130 . This is because after the laminated body is formed, the laminate is laminated by thermocompression bonding around the core material 110 .

The first resin material 120 and the second resin material 130 are formed of the same or different types of resin compositions having different compositions, and are provided with different physical properties such as use, function, performance or characteristics. In this case, mechanical properties such as hardness and strength or thermal properties such as coefficient of thermal expansion (CTE) may be exemplified as physical properties.

Specifically, the first resin material 120 and the second resin material 130 may be composed of a photo-sensitivity resin composition or a thermosetting composition, in this case, the first resin in the space between the fabric or glass filaments. As the material 120 or the second resin material 130 is impregnated without voids and cured, the core material 110 having a high modulus may be configured.

The photosensitive resin composition may be a photocurable resin that is cured by light. In this case, the curing speed of the resin material can be controlled by a relatively easy method of irradiating light during the compression process with the core material 110 .

As long as the photocurable resin is a resin that is cured by light, known materials are limited.

It may be employed without, for example, an ultraviolet curable resin that is cured by ultraviolet rays (UV). For example, an acrylic resin may be used as the ultraviolet curable resin.

The thermosetting composition may be a thermosetting resin that is cured by heat. In this case, the curing speed of the resin material can be controlled by a method of applying heat during the compression process with the core material 110 .

As the thermosetting resin, any known material may be employed without limitation as long as it is a resin that is cured by heat, for example, a urea resin, a melamine resin, a bismarimide resin, a polyurethane resin, a resin having a benzoxazine ring, and a cyanate ester resin. , a bisphenol S-type epoxy resin, a bisphenol F-type epoxy resin, and a copolymerized epoxy resin of bisphenol S and bisphenol F, etc. may be used. Among these, it is preferable to use a cyanate resin especially, and in this case, the thermal expansion coefficient of the prepreg 100 can be made small.

The type or molecular weight of the photocurable resin or thermosetting resin may be appropriately selected in consideration of the target hardness, strength, coefficient of thermal expansion (CTE) of the first resin material 120 and the second resin material 130 .

In the present invention, when the first resin material 120 and the second resin material 130 are formed of a photocurable resin, the first resin material 120 and the second resin material 130 accelerate the photopolymerization to make the photocurable resin material. It contains a photoinitiator to allow curing of the resin.

Preferably, the first resin material 120 has a higher photoinitiator content than the second resin material 130 , and thus, under the same light conditions during the prepreg 100 manufacturing process, relative to the second resin material 130 . By quickly controlling the curing speed, it is possible to achieve a higher degree of curing or hardness than the second resin material 130 .

For example, the first resin material 120 preferably contains about 3 wt % to 5 wt % of the photoinitiator relative to the total of the first resin composition constituting the first resin material 120 .

At this time, if the content of the photoinitiator of the first resin material 120 is less than 3% by weight relative to the total of the first resin composition, the desired degree of curing or hardness cannot be obtained, and if it exceeds 5% by weight, the stability at the time of prepreg storage will be reduced. can

On the other hand, it is preferable that the second resin material 130 contains about 0.1 wt% or more and less than 3 wt% of the photoinitiator relative to the entire second resin composition constituting the second resin material 130 .

At this time, if the photoinitiator content of the second resin material 130 is less than 0.1% by weight relative to the total of the second resin composition, the photoinitiation effect may be insufficient, and if it is 3% by weight or more, the curing rate is the same as compared to the first resin material 120 or faster, it may be difficult to secure the surface flatness of the upper portion of the first resin material 120 .

On the other hand, as long as the first resin material 120 has a photoinitiator content that can implement a higher degree of curing or hardness than the second resin material 130 , the photoinitiator in the first resin material 120 and the second resin material 130 . Of course, the content may be variously designed within the range of 0.1 wt% to 5 wt% of each resin composition as a whole.

As the photoinitiator, known substances such as compounds that generate radical molecules by decomposition by irradiation of light such as ultraviolet light can be employed without limitation, for example, benzophenone, acetophenone, fluorenone, benzaldehyde, propiophenone, anthra Quinone, carbazole, 3 or 4 methylacetophenone, 3 or 4 methoxybenzophenone, 4,4' dimethoxy benzophenone, allyl acetophenone, 2,2'-diphenoxy acetophenone, benzoin, ethyl benzoin and ether, benzoin acetate, carbamic acid benzoin phenyl, acrylic acid benzoin, benzoin phenyl ether, benzoyl peroxide, asyrphosphane oxide, and chlorine methyl anthraquinone. These can be used independently and can use 2 or more types together.

On the other hand, when the first resin material 120 and the second resin material 130 are formed of a thermosetting resin, the first resin material 120 and the second resin material 130 use a curing accelerator to increase the curing speed. include

The first resin material 120 has a higher curing accelerator content than the second resin material 130 , and thus, under the same thermal conditions during the manufacturing process of the prepreg 100 , the curing rate is reduced from the second resin material 130 . By controlling it relatively quickly, the degree of curing or hardness can be higher than that of the second resin material 130 .

For example, the first resin material 120 preferably includes a curing accelerator in an amount of about 1 wt % to 3 wt % relative to the entire first resin composition constituting the first resin material 120 .

At this time, if the curing accelerator content of the first resin material 120 is less than 1% by weight relative to the total amount of the first resin composition, the desired degree of curing or hardness cannot be obtained, and if it exceeds 3% by weight, stability during prepreg storage is reduced can be

On the other hand, the second resin material 130 preferably contains about 0.01 wt% or more and less than 1 wt% of the curing accelerator relative to the entire second resin composition constituting the second resin material 130 .

At this time, if the curing accelerator content of the second resin material 130 is less than 0.01% by weight relative to the total of the second resin composition, the effect of accelerating curing may be insufficient, and if it is 1% by weight or more, curing compared to the first resin material 120 Since the speed is the same or faster, it may be difficult to secure the surface flatness of the upper portion of the first resin material 120 .

On the other hand, as long as the first resin material 120 has a curing accelerator content capable of realizing a higher degree of curing or hardness than the second resin material 130 , the first resin material 120 and the second resin material 130 . Of course, the content of the curing accelerator may be variously designed within the range of 0.01% to 3% by weight relative to the total of each resin composition.

As the curing accelerator, known materials can be employed without limitation, for example, aliphatic polyamines, aromatic polyamines, secondary amines, tertiary amines, imidazole derivatives, organic acid hydrazide, dicyandiamide and its derivatives, urea Derivatives and the like can be used, and among these, an imidazole derivative is more preferable.

By using such an imidazole compound, the heat resistance of a resin composition can be improved, and at the same time, low thermal expansibility (a property with a low expansion rate by heat|fever) and low water absorption to the resin material formed from this resin composition can be provided.

The first resin material 120, including the photoinitiator or curing accelerator having the configuration as described above, has a pencil hardness of approximately 2B to 4B and a degree of curing of 90% or more, that is, 90% to 100%, and the second resin material 130 ) has a pencil hardness of approximately 3B to 6B and a degree of curing of 85% or more and less than 90%.

In the present invention, the degree of curing or hardness of the first and second resin materials 120 and 130 is increased in proportion to the content of the photoinitiator or curing accelerator. By increasing the degree of hardening or hardness of the first resin material 120 relatively in the compression process with the core material 110 by the content of the photoinitiator or curing accelerator, the surface of the first resin material 120 becomes the surface of the core material 110 . It is possible to control so as not to follow the curved portion, and through this, the unevenness of the surface roughness of the upper surface of the first resin material 120 becomes smaller and surface flatness can be secured.

In addition, the second resin material 130 is formed to have a lower degree of curing or hardness than the first resin material 120 , so that it is more flexible than the first resin material 120 , so that wiring embedding can be improved.

Although the first resin material 120 will be described in more detail in the following prepreg manufacturing method, the upper portion of the core material 110 is applied to the substrate 140 and in a semi-hardened (B-stage) state of approximately 70 to 80% curing degree. The core material 110 is impregnated with a certain thickness while being laminated to, applying light or heat, and at the same time applying pressure to a certain thickness (X) and curing with a degree of hardening of 90% or more or pencil hardness of 2B to 4B. .

The second resin material 130 will be described in more detail in the following prepreg manufacturing method, but it is applied to the substrate 140 and the lower portion of the core material 110 in a semi-hardened (B-stage) state of approximately 70 to 80% curing degree. The core material 110 is laminated on, and cured to a certain thickness by applying light or heat, and at the same time applying pressure to a certain thickness (Y) of 85% or more, less than 90% curing degree or 3B to 6B pencil hardness. ) while being impregnated, one surface is bonded to the first resin material 120 and laminated.

Accordingly, in the prepreg 100 , the bonding interface between the first resin material 120 and the second resin material 130 is located within the thickness Z range of the core material 110 .

During the compression process, the first resin material 120 is cured faster than the second resin material 130 , so that the impregnation rate of the core material 110 in the first resin material 120 is relatively high, so substantially the first The bonding interface between the resin material 120 and the second resin material 130 is located at the upper portion within the thickness Z range of the core material 110 .

In addition, the second resin material 130 may be formed to have the same thickness as the first resin material 120 . In FIG. 1 , the thickness of the first resin material 120 is defined as X, and the thickness of the second resin material 130 is defined as Y, and in this case, a relational expression of X=Y is established between them.

As such, the first and second resin materials 120 and 130 are manufactured using a method applied to the base material 140 , so that the thickness of the resin material can be precisely controlled to have a relatively thin thickness.

The prepreg 100 of the first embodiment configured as described above includes first and second resin materials 120 and 130 made of a photocurable resin or a thermosetting resin, and the first and second resin materials 120 and 130 are By being impregnated and hardened in the core material 110, the core material 110 impregnated with the first and second resin materials 120 and 130 serves as a core of the prepreg, so that it can be manufactured in a thin form and low coefficient of thermal expansion (CTE) and high thermal conductivity (Tg).

In addition, the prepreg 100 of the first embodiment has excellent upper surface flatness by increasing the degree of curing of the first resin material 120 relatively through adjustment of the content of the photoinitiator or curing accelerator even when the core material 110 is applied. Accordingly, the prepreg 100 can apply a semi-additive process (SAP) method when forming a circuit layer on the prepreg 100, and improve circuit disconnection and short circuit due to incomplete etching of the microcircuit pattern. implementation is possible.

In the prepreg 100 of the first embodiment configured as described above, a large amount of the same or different inorganic or organic fillers may be further included in the core 110 impregnated with the first and second resin materials 120 and 130 . The reason for further containing the filler in the first and second resin materials 120 and 130 impregnated in the core 110 is that only the first and second resin materials 120 and 130 that are photocurable or thermosetting are the core materials 110 . ), it is possible to increase the rigidity of the core material 110 by curing the resin, but since the coefficient of thermal expansion is high and thus vulnerable to thermal deformation, the coefficient of thermal expansion is kept low by the inclusion of a filler to warp during thermocompression bonding. This is because deformation can be minimized.

Meanwhile, the base material 140 may be further laminated on the exposed surfaces of the first and second resin materials 120 and 130 corresponding to the thickness direction of the core material 110 .

The substrate 140 serves as a support in the process of preparing the first resin material 120 and the second resin material 130 by application such as a casting method, and may include a metal foil or an insulating film. . Examples of the metal foil include copper foil, aluminum foil, nickel foil, chrome foil, gold foil, and silver foil. The insulating film may be, for example, a polyethylene terephthalate film, a polypropylene film, a polyethylene film, a polycarbonate film, a polyethylene naphthalate film, a polyarylate film, a nylon film, or the like.

The substrate 140 may be selected from a metal foil or an insulating film according to a method of a micro circuit pattern to be implemented on the prepreg 100 among the SAP method and the MSAP method.

When the substrate 140 is composed of copper foil, the prepreg 100 is composed of a copper clad laminate (CCL), and the copper foil layer of the copper clad laminate is then formed as a wiring layer of a multilayer printed circuit board.

On the other hand, when any one of the substrate 140 is composed of a metal foil and the other is composed of an insulating film, the metal foil is then formed as a wiring layer of a multilayer printed circuit board, and the insulating film is then a buildup layer of the multilayer printed circuit board (Build-up layer) may be formed.

In FIG. 1 , the substrate 140 is shown to be formed on both the exposed surfaces of the first resin material 120 and the second resin material 130 , but the first resin material 120 or the second resin material 130 . ) may be formed only on the exposed surface of any one selected from.

Meanwhile, FIG. 2 is a cross-sectional view of a prepreg according to a second embodiment of the present invention, and FIG. 3 is a cross-sectional view of a prepreg according to a third embodiment of the present invention.

In the second and third embodiments, the same reference numerals are assigned to the same components as those of the embodiment of FIG. 1 described above, and overlapping descriptions of the same components in the second and third embodiments will be omitted. decide to do

2 and 3 , the first resin material 120 and the second resin material 130 may be formed to have different thicknesses.

As shown in FIG. 2 , the first resin material 120 may be formed to be thicker than the second resin material 130 . Here, when the thickness of the first resin material 120 is defined as X and the thickness of the second resin material 130 is defined as Y, the relation between X>Y is established.

Alternatively, as shown in FIG. 3 , the second resin material 130 may be formed to be thicker than the first resin material 120 . Here, when the thickness of the first resin material 120 is defined as X and the thickness of the second resin material 130 is defined as Y, a relational expression of X<Y is established between them.

That is, in the present embodiments, when the thickness of the core material 110 is defined as Z, the thickness of the first resin material 120 is defined as X, and the thickness of the second resin material 130 is defined as Y, the thickness of the core material 110 is between them. In consideration of impregnation property, wiring embedding property, mechanical and thermal properties, and bending property, X+Y≥Z, and the relationship of X=Y or X>Y or X<Y may be satisfied.

A manufacturing method for the prepreg of the present embodiments configured as described above is as follows.

In the prepreg of the present embodiments, the following manufacturing method will be mainly described with respect to the embodiment shown in FIG. 1 , and the manufacturing method difference from the embodiment shown in FIG. 1 is the thickness of the resin material laminated on the upper and lower parts of the core material. However, since the manufacturing methods are the same except for the differences, a representative manufacturing method will be mainly described.

4 to 6 are process diagrams showing a method for manufacturing a prepreg according to a first embodiment of the present invention. FIG. 4 is a cross-sectional view of a first resin material, a second resin material and a core material, and FIG. It is a cross-sectional view in which the first and second resin materials are laminated on the lower part, and FIG. 6 is a cross-sectional view of the prepreg in which the first and second resin materials are impregnated into the core material.

As shown in FIG. 4, the prepreg of this embodiment first prepares a fabric or glass filament core 110 of fabric or glass cloth woven in 1 to 3 rows. As mentioned above, the core material 110 is composed of a woven material having a bent portion, and may be formed by overlapping fabric or glass filaments with upper and lower surfaces.

In addition, each of the first resin material 120 and the second resin material 130 is prepared. The first resin material 120 is in a semi-cured (B-stage) state having a degree of curing of about 70 to 80% on the substrate 140 of the metal foil or insulating film, and a photo-curable resin or thermosetting resin containing a photo initiator or curing accelerator It can be formed by coating with a certain thickness.

The second resin material 130 is in a semi-cured (B-stage) state having a degree of curing of about 70 to 80% on the substrate 140 of the metal foil or insulating film, and contains a photoinitiator or curing accelerator more than the first resin material 120 . It can be formed by applying a photocurable resin or thermosetting resin of the same or different material having a low content to a predetermined thickness.

As a method of applying the first resin material 120 and the second resin material 130 on the substrate 140, a casting method of applying a resin composition in a slurry state may be used, but is not particularly limited thereto. and a known coating method by a conventional dry process that does not use an impregnation bath may be appropriately employed.

As mentioned above, when the first and second resin materials 120 and 130 are formed by the coating method, the thickness can be precisely controlled, so that the thickness can be reduced.

On the other hand, each of the first resin material 120 and the second resin material 130 is subjected to UV curing or thermal curing after applying each resin composition in an uncured (A-stage) state to the same thickness on the substrate 140 . It can also be formed by curing to a semi-cured state of the B-stage having a degree of hardening of about 70 to 80%.

Next, as shown in FIG. 5 , the first resin material 120 and the second resin material 130 are laminated on the upper and lower portions of the core material 110 . Accordingly, a resin laminate (not shown) in which the core material 110 is interposed between the first resin material 120 and the second resin material 130 is formed, and the first resin material 120 and the second resin material are formed. Ash 130 is disposed to face each other.

Next, as shown in FIG. 6 , light or heat is applied to the resin laminate of FIG. 5 in which the first resin material 120 and the second resin material 150 are laminated on and below the core 110 , and this Simultaneously apply pressure to compress.

The resin laminate of FIG. 5 is compressed as shown in FIG. 6 through a pressing method such as V-press, V-lamination, roll-press or roll-lamination.

In particular, the curing rate compared to the impregnation rate of the core material 110 with respect to the first resin material 120 by the light irradiated to the resin laminate or heat applied to the resin laminate while the resin laminate is compressed is quickly controlled.

In the resin laminate of FIG. 5 , the first resin material 120 and the second resin material 130 are impregnated into the core material 110 by thermocompression bonding, and the first resin material 120 and the second resin material are opposed to each other. One side of 130 is laminated to form an integral body by bonding.

At this time, the prepreg 100 in which the bonding interface between the first resin material 120 and the second resin material 130 to be bonded is located within the thickness range of the core material 110 is manufactured, and substantially the A bonding interface between the first resin material 120 and the second resin material 130 is positioned at the upper portion within the thickness range.

In addition, the first resin material 120 impregnated in the core material 110 is cured by light or heat applied during compression to maintain a degree of hardening of about 90% or more or a pencil hardness of 2B to 4B, and to the core material 110 . The impregnated second resin material 130 may be cured by light or heat applied during compression to maintain a degree of curing of about 85% or more, less than 90%, or pencil hardness of 3B to 6B.

On the other hand, each of Figures 7 and 8 is a process diagram for a method of manufacturing a prepreg according to a second embodiment and a third embodiment of the present invention, Figure 7 is a second resin material laminated on the core material thinner than the first resin material. It is a process diagram formed, and FIG. 8 is a process diagram in which the first resin material laminated on the core material is formed thinner than the second resin material.

As shown, according to the prepreg manufacturing method of this embodiment, before laminating the first resin material 120 and the third resin material 130 on the upper and lower portions of the core material 110, the first resin material 120 In the step of preparing the and the second resin material 130 , the first resin material 120 and the second resin material 130 may be laminated with a predetermined thickness of resin to have different thicknesses.

That is, as shown in FIG. 7 , the second resin material 130 to be stacked on the lower part of the two kinds of resin materials to be stacked on the upper and lower parts of the core 110 is thinner than the first resin material 120 to be stacked on the upper part. can be

In addition, as shown in FIG. 8 , the first resin material 120 to be stacked on the upper part of the two kinds of resin materials to be stacked on the upper and lower parts of the core 110 is thinner than the second resin material 130 to be stacked on the lower part. can be

In this way, when the first resin material 120 and the second resin material 130 having different thicknesses are prepared, the first resin material 120 is disposed on the upper and lower portions of the core 110 as in the embodiment of FIG. 5 . and the second resin material 130 are laminated to form a resin laminate, and then light or heat is applied to the resin laminate as in the embodiment of FIG. do.

In the prepreg manufactured through the manufacturing method of the embodiment shown in FIGS. 7 and 8 , the first resin material 120 and the second resin material 130 are impregnated in the core material 110 and stacked, the core material 110 . A circuit is formed on the surface of a thin resin material laminated on one surface of the core 110 among resin materials of different thickness around A circuit pattern may be formed. Accordingly, the prepreg of this embodiment can be manufactured in a thin printed circuit board.

The prepreg 100 of this embodiment manufactured with the above configuration and manufacturing method has a relatively flat surface that does not follow the bent portion of the core 110 even when the core 110 is introduced.

Accordingly, the prepreg 100 can apply the SAP method when the circuit layer is formed thereon, and it is possible to implement a fine circuit pattern by improving the disconnection and short circuit of the circuit due to incomplete etching.

The prepreg 100 of this embodiment is mainly applied as a core of a printed circuit board due to the high modulus and low coefficient of thermal expansion of the core material 110, and may also be applied to a build-up layer in a multi-layer printed circuit board whose main purpose is to prevent warpage.

In addition, according to the present invention, since the prepreg 100 can be manufactured only by a dry process, the resin material can be manufactured with a thinner thickness than when manufacturing the resin material using the existing wet impregnation method, so that the thickness of the prepreg can be reduced do.

Preferred embodiments of the present invention described above are disclosed for the purpose of illustration, and for those of ordinary skill in the art to which the present invention pertains, various substitutions, modifications and changes within the scope not departing from the technical spirit of the present invention This would be possible, but such substitutions, changes, etc. should be regarded as belonging to the following claims.

100: prepreg 110: heartwood
120: first resin material 130: second resin material
140: description

Claims (8)

heartwood;
a first resin material laminated on the core material; and
Including; a second resin material laminated on the lower portion of the core material,
A bonding interface between the first resin material and the second resin material is located within the thickness range of the core material,
The first and second resin materials include a photoinitiator,
The first resin material is a prepreg having a higher content of the photoinitiator and a degree of curing or hardness than the second resin material.
According to claim 1,
The bonding interface between the first resin material and the second resin material is
A prepreg positioned on the top within the thickness range of the core material.
According to claim 1,
The core material is a prepreg of any one of fabric or glass filaments intersecting each other and woven fabric cloth (fabric cloth) or glass cloth (glass cloth).
According to claim 1,
The first resin material and the second resin material are prepregs formed of a photocurable resin.
According to claim 1,
The first resin material is a prepreg having different physical properties from the second resin material.
According to claim 1,
The core material is a prepreg that further includes a filler in the first resin material and the second resin material.
According to claim 1,
The first resin material is a prepreg formed to have the same thickness as the second resin material.
According to claim 1,
The first resin material is a prepreg having a thickness different from that of the second resin material.

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