TW201902648A - Auxiliary plate for micro diameter drilling and drilling method using the same - Google Patents

Abstract

An entry sheet for boring a very fine drill hole with a diameter of 0.075 mm or less, the entry sheet having a metal foil, and, on at least one side of the metal foil, a layer of a resin composition containing a polyolefin resin (A), a low-molecular weight water-soluble lubricant (B), and a water-soluble resin (C), wherein the water-soluble resin (C) contains a high-molecular weight water-soluble resin (c-1) and a medium-molecular weight water-soluble resin (c-2), and per 100 parts by mass in total of the polyolefin resin (A), the low-molecular weight water-soluble lubricant (B) and the water-soluble resin (C), an amount of the polyolefin resin (A) is at least 15 parts by mass but not more than 25 parts by mass, an amount of the low-molecular weight water-soluble lubricant (B) is at least 5 parts by mass but not more than 40 parts by mass, and an amount of the water-soluble resin (C) is at least 35 parts by mass but not more than 80 parts by mass.

Description

Auxiliary plate for micro-diameter drilling and drilling method using the same

The present invention relates to an auxiliary plate for micro-diameter drilling processing and a drilling processing method using the auxiliary plate.

As for the drilling processing method of laminated boards and multilayer boards used for printed circuit board materials, the following methods are generally used: one or more laminated boards or multilayer boards are stacked and arranged as abutting boards at the top A sheet of aluminum foil alone or a layer of a resin composition formed on the surface of the aluminum foil (hereinafter, this "sheet" is referred to as an "auxiliary plate for drilling processing" in this specification), and a hole is processed.

In recent years, with the requirements for the reliability improvement of printed circuit boards and the progress of high density, the drilling of laminated or multilayer boards also requires high-quality drilling such as improved hole position accuracy and reduced hole wall roughness. machining.

In order to respond to the above-mentioned requirements for improved hole position accuracy and reduced hole wall roughness, for example, Patent Document 1 proposes a hole-cutting method using a plate made of a water-soluble resin such as polyethylene glycol. In addition, Patent Document 2 proposes a lubricant sheet for hole processing in which a water-soluble resin layer is formed on a metal foil. Furthermore, Patent Document 3 proposes an auxiliary plate for hole processing in which a water-soluble resin layer is formed on an aluminum foil on which a thermosetting resin film has been formed. Furthermore, Patent Document 4 proposes a lubricant sheet for hole processing obtained by blending a halogen-free coloring agent in a lubricating resin composition.

It has been proposed that a form consisting of a metal foil and a layer of a resin composition formed on at least one side of the metal foil is one form of an auxiliary plate for drilling. However, the adhesion strength between the metal foil and the resin composition layer is weak. Therefore, if the metal foil and the resin composition layer are in direct contact with each other for the auxiliary plate for drilling processing, the resin tends to occur during the drilling process. The layer of the composition is peeled off, and the drill follows the layer of the resin composition that has been peeled off, causing the hole position accuracy to deteriorate and the frequency of breakage of the drill to deteriorate. In addition, the auxiliary plate for drilling processing is generally arranged on both sides of a multi-layer laminated board or a multilayer board and is made into a group with a fixing tape for opening processing, but the fixing tape may The layers of the resin composition are peeled together, causing the position of the auxiliary plate to deviate. Therefore, in order to improve the adhesion strength between the metal foil and the resin composition layer, it is practical to form a urethane-based compound, a vinyl acetate-based compound, or a vinyl chloride-based compound between the metal foil and the resin composition layer. Compounds, polyester-based compounds, and their polymers, epoxy-based compounds, cyanate-based compounds, and the like are used in the form of an adhesive layer (adhesive film) (for example, refer to Patent Document 5). [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 4-92494 [Patent Document 2] Japanese Patent Laid-Open No. 5-169400 [Patent Document 3] Japanese Patent Laid-Open No. 2003-136485 [Patent Document 4] Japanese Patent Laid-Open No. 2004-230470 [Patent Document 5] Japanese Patent Laid-Open No. 2011-183548

[Problems to be Solved by the Invention]

However, on the other hand, if an adhesive layer is provided between the metal foil and the resin composition layer, the adhesive layer may hinder the lubricating effect of the resin composition. Therefore, it may have important characteristics required for an auxiliary plate for drilling processing. That is, the hole position accuracy deteriorates. Therefore, it is desired to develop an auxiliary plate for drilling processing in which an adhesive layer is not provided between the metal foil and the resin composition layer, the adhesive strength of the metal foil and resin composition layer is strong, and the hole position accuracy is excellent.

In addition, printed circuit boards continue to progress toward higher densities. Recent trends in the drilling of laminated boards and multilayer boards include the following features. First, due to the high density of wiring circuits, the interval between drilled holes becomes narrower and narrower. That is, in order to maintain the insulation between the drilled holes, excellent hole position accuracy is important.

Second, drilling holes are becoming smaller, and drills with a diameter of 0.075mmΦ ~ 0.05mmΦ have begun to be widely used. As the diameter of the drill bit becomes smaller, the rigidity of the drill bit becomes lower, so drill breakage during drilling becomes a problem. That is, excellent drill break resistance is required.

The present invention has been made in view of the above-mentioned problems, and an object thereof is to provide an auxiliary plate for drilling processing, even if an adhesive layer is not provided between the metal foil and the resin composition layer, and the metal foil and the resin composition layer are provided. The adhesive strength is still strong. When using a drill with a diameter of less than 0.075mm for drilling, the hole position accuracy is excellent, and the drill bit break resistance is also excellent; and a drilling method using the auxiliary plate is provided. [Means for solving problems]

The present inventors conducted various investigations in order to solve the above-mentioned problems. As a result, they found that the layer of the resin composition formed on the surface of the metal foil contained a polyolefin resin (A), a low-molecular-weight water-soluble lubricant (B), and a water-soluble resin (C), and the contents of the polyolefin resin (A), the low-molecular-weight water-soluble lubricant (B), and the water-soluble resin (C) in the layer of the resin composition are each in a specific range, which can solve the above problems, but The present invention has been completed.

That is, the present invention is as follows. [1] An auxiliary plate for drilling a micro-diameter with a diameter of 0.075 mm or less, comprising: a metal foil; and a polyolefin resin (A) and a low-molecular-weight water-soluble lubricant (at least on one side of the metal foil) B). A layer of a resin composition with a water-soluble resin (C). The water-soluble resin (C) contains a high-molecular-weight water-soluble resin (c-1) and a medium-molecular-weight water-soluble resin (c-2). The polyolefin resin (A), the low-molecular-weight water-soluble lubricant (B), and the water-soluble resin (C) total 100 parts by mass, and the content of the polyolefin resin (A) is 15 parts by mass or more and 25 parts by mass or less The content of the low-molecular-weight water-soluble lubricant (B) is 5 parts by mass or more and 40 parts by mass or less, and the content of the water-soluble resin (C) is 35 parts by mass or more and 80 parts by mass or less. [2] The auxiliary plate for drilling with a fine diameter of 0.075 mm or less as in [1], wherein the polyolefin resin (A) contains a constituent unit derived from an olefin and a constituent derived from acrylic acid and / or methacrylic acid Unit olefin- (meth) acrylic copolymer. [3] The auxiliary plate for drilling with a fine diameter of 0.075 mm or less as in [2], wherein the constituent unit derived from olefin contains a constituent unit derived from ethylene. [4] The auxiliary plate for drilling a micro-diameter with a diameter smaller than 0.075 mm as in [2] or [3], wherein the olefin- (meth) acrylic copolymer has a structure of the following general formula (1) Ethylene- (meth) acrylic block copolymer; (1) In formula (1), R ₁ , R ₂ , and R ₃ each independently represent a hydrogen atom or a methyl group, and m and n are each independently an integer of 1 or more. [5] The auxiliary plate for drilling with a fine diameter of 0.075 mm or less according to any one of [2] to [4], wherein the olefin- (meth) acrylic copolymer is derived from the olefin The content of the structural unit is 60 to 99 mol% relative to the total 100 mol% of the structural unit derived from the olefin and the structural unit derived from the acrylic acid and / or the methacrylic acid. [6] The auxiliary plate for drilling with a fine diameter of 0.075 mm or less according to any one of [1] to [5], wherein the weight average molecular weight of the polyolefin resin (A) is 5 × 10 ³ or more 1 × 10 ⁵ or less. [7] The auxiliary plate for drilling with a fine diameter of 0.075 mm or less according to any one of [1] to [6], wherein the weight-average molecular weight of the low-molecular-weight water-soluble lubricant (B) is 6 × 10 ² or more and 2.5 × 10 ³ or less. [8] The auxiliary plate for drilling with a fine diameter of 0.075 mm or less according to any one of [1] to [7], wherein the low-molecular-weight water-soluble lubricant (B) is selected from polyethylene glycol Glycol compounds such as polytetramethylene glycol, polyoxyethylene oleyl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, polyoxyethylene lauryl ether, polyoxyethylene nonylphenyl ether, polyoxyethylene Mono-ether compounds of polyoxyethylene such as octylphenyl ether, polyoxyethylene monolaurate, polyoxyethylene monostearate, polyoxyethylene monooleate, polyoxyethylene distearate, polyoxyethylene Sorbitan monolaurate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan monooleate, polyglycerol monostearate compounds, polyoxyethylene propylene copolymers, and their One or more of the group consisting of derivatives. [9] The auxiliary plate for drilling with a fine diameter of 0.075 mm or less according to any one of [1] to [8], wherein the water-soluble resin (C) contains a material selected from the group consisting of polyethylene oxide, polymer Polypropylene oxide, polyvinylpyrrolidone, cellulose derivative, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyoxyethylene monoether compound, polyoxyethylene monostearate, polyoxyethylene One or more types of sorbitan monostearate, polyglycerol monostearate compound, polyethylene oxide-polypropylene oxide copolymer, and their derivatives. [10] The auxiliary plate for drilling with a fine diameter of 0.075 mm or less according to any one of [1] to [9], wherein the thickness of the layer of the resin composition is 0.02 to 0.3 mm. [11] The auxiliary plate for drilling with a fine diameter of 0.075 mm or less according to any one of [1] to [10], wherein the thickness of the metal foil is 0.05 mm to 0.3 mm. [12] A method for drilling a micro-diameter with the following steps: Use an auxiliary plate for drilling a micro-diameter having a diameter of 0.075 mm or less as in any of [1] to [11], and use a diameter of 0.075 mm or less A drill for micro-diameter drilling is used to form holes in laminated or multilayer boards. [Effect of the invention]

According to the present invention, an auxiliary plate for drilling can be provided. Even if an adhesive layer is not provided between the layer of the metal foil and the resin composition, the adhesion strength of the layer of the metal foil and the resin composition is still strong. The drill with a fine diameter of less than 0.075mm is used for drilling with excellent hole position accuracy and drill bit breakage resistance, and it can provide a drilling method using the auxiliary plate. In addition, there is no need to provide an adhesive layer, so the cost of raw materials can be reduced, and the manufacturing steps of the auxiliary plate for drilling processing can be simplified.

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

[Auxiliary plate for drilling processing] An auxiliary plate (hereinafter, also simply referred to as an "auxiliary plate") for drilling a micro-diameter with a diameter of 0.075 mm or less in this embodiment, includes a metal foil, and at least A layer of a resin composition comprising a polyolefin resin (A), a low-molecular-weight water-soluble lubricant (B), and a water-soluble resin (C) on one side of a metal foil, and the water-soluble resin (C) contains a high-molecular-weight water-soluble The resin (c-1) and the medium molecular weight water-soluble resin (c-2) are 100 with respect to the total of the polyolefin resin (A), the low-molecular-weight water-soluble lubricant (B), and the water-soluble resin (C). The content of the polyolefin resin (A) is 15 parts by mass or more and 25 parts by mass or less, and the content of the low-molecular-weight water-soluble lubricant (B) is 5 parts by mass or more and 40 parts by mass or less. The water-soluble resin (C ) Is contained in an amount of 35 parts by mass or more and 80 parts by mass or less.

FIG. 1 shows an aspect of an auxiliary plate for drilling processing and a method of drilling processing using the auxiliary plate in the present embodiment. As shown in FIG. 1, the auxiliary plate of this embodiment includes a metal foil 2 and a layer 1 of a resin composition arranged on at least one side of the metal foil 2. By using the layer 1 of the resin composition having the above-mentioned composition, even if an adhesive layer is not provided between the metal foil 2 and the layer 1 of the resin composition, the adhesion strength between the metal foil 2 and the layer 1 of the resin composition is obtained. Auxiliary plate that is still strong and has excellent hole position accuracy during drilling and excellent drill breakage resistance. Therefore, the auxiliary plate of this embodiment may not have an adhesive layer between the metal foil and the resin composition layer for adjusting the adhesion between the metal foil and the resin composition layer. Hereinafter, the configuration of the auxiliary plate of this embodiment will be described in more detail.

[Metal Foil] The material of the metal foil is not particularly limited, and is preferably a metal material having high adhesion to a layer of a resin composition described later and capable of withstanding the impact caused by a drill. Regarding the type of metal of the metal foil, from the viewpoints of availability, cost, and processability, for example, aluminum can be cited. As far as the material of aluminum foil is concerned, aluminum with a purity of more than 95% is preferred. Examples of such aluminum foil include 5052, 3004, 3003, 1N30, 1N99, 1050, 1070, 1100, 1085, and 8021 specified in JIS-H4160. By using an aluminum foil with an aluminum purity of 95% or more as the metal foil, the impact caused by the drill bit is reduced, and the penetration of the drill tip is improved, and the lubricating effect of the drill bit brought by the resin composition is complementary, and it can be more effective. Improve the hole position accuracy of the machined hole.

The thickness of the metal foil should be 0.05 ~ 0.5mm, more preferably 0.05 ~ 0.3mm. When the thickness of the metal foil is 0.05 mm or more, there is a tendency that the occurrence of burrs in the object to be punched (for example, a laminated board) during drilling is more suppressed. In addition, when the thickness of the metal foil is 0.5 mm or less, the chips generated during the drilling process tend to be more easily discharged.

The thickness of each layer constituting the auxiliary plate of this embodiment is measured as follows. First, use a profile polisher (manufactured by Japan Electronics DATUM Co., Ltd. under the trade name "CROSS-SECTION POLISHER SM-09010") or an ultra-thin microtome (manufactured by Leica, model "EM UC7"). The stacking direction of each layer is cut. Then, using a SEM (Scanning Electron Microscope, manufactured by KEYENCE Corporation, model "VE-7800"), the section is viewed from a direction perpendicular to the section that appears when cut, and the layers such as metal foil are measured. And the thickness of the layer of the resin composition. The thickness was measured at 5 places per field of view, and the average value was defined as the thickness of each layer.

[Layer composition layer] The resin composition layer is disposed on at least one side of the metal foil, and contains a polyolefin resin (A), a low-molecular-weight water-soluble lubricant (B), and a water-soluble resin (C).

(Polyolefin resin (A)) The polyolefin resin (A) is not particularly limited, and examples thereof include: homopolymers of olefins; copolymers of olefins and other comonomers capable of copolymerizing with olefins. Examples of the olefin include ethylene, propylene, butene, hexene, and octene. Among them, ethylene and propylene are preferred, and ethylene is more preferred. Polyolefin resin (A) may be used individually by 1 type, and may use 2 or more types together.

The olefin homopolymer is not particularly limited, and examples thereof include polyethylene resins, polypropylene resins, polybutadiene resins, cycloolefin resins, and polybutene resins.

The comonomer constituting the olefin copolymer is not particularly limited as long as it has a functional group capable of polymerizing with the olefin, and examples thereof include vinyl-based monomers such as vinyl acetate and vinyl alcohol; Unsaturated carboxylic acid-based monomers such as acrylic acid, methacrylic acid, maleic acid, itaconic acid, and fumaric acid; unsaturated ester-based monomers such as methacrylate and acrylate. Among them, acrylic acid and methacrylic acid are preferable, and acrylic acid is more preferable. In addition, a resin having a constituent unit derived from two olefins, such as an ethylene-propylene copolymer resin, is also included in the olefin copolymer.

Among them, the polyolefin resin (A) is preferably a copolymer (hereinafter, also referred to as "olefin-unsaturated carboxylic acid copolymer") containing a constituent unit derived from an olefin and a constituent unit derived from an unsaturated carboxylic acid-based monomer, It is a copolymer (hereinafter, also referred to as "olefin- (methyl)" containing a structural unit derived from an olefin and a structural unit derived from acrylic acid and / or methacrylic acid (hereinafter, also referred to as "(meth) acrylic acid"). Acrylic copolymer ") is more preferably a copolymer containing constituent units derived from ethylene and constituent units derived from acrylic acid and / or methacrylic acid (hereinafter, also referred to as" ethylene- (meth) acrylic copolymer "). More preferably, it is a copolymer containing a structural unit derived from ethylene and a structural unit derived from acrylic acid. By using such a polyolefin resin (A), the adhesion strength of the layer of the metal foil and the resin composition is further improved, and the resin composition layer is peeled off due to poor hole position accuracy during drilling and drill breakage. There is a tendency to be more suppressed. Therefore, the accuracy of the hole position is further improved, and the processing life of the drill tends to be longer.

The olefin- (meth) acrylic copolymer is not particularly limited, and examples thereof include ethylene- (meth) acrylic block copolymers having a structure of the following general formula (1). By using such an ethylene- (meth) acrylic block copolymer, the adhesion strength of a layer having a metal foil and a resin composition is further improved, and the hole position accuracy during drilling processing tends to be more improved. In particular, by forming a block copolymer, the crystallinity is more fully improved, and it is efficiently melted during the drilling process, so the hole position accuracy tends to be further improved. [Chemical 2] (1) (In the formula (1), R ₁ , R ₂ , and R ₃ each independently represent a hydrogen atom or a methyl group, and m and n are each independently an integer of 1 or more.)

In the general formula (1), m is 1 or more, preferably 200 or more, and more preferably 500 or more. The upper limit of m is preferably 3400 or less, more preferably 2500 or less, and even more preferably 2000 or less. In the general formula (1), n is 1 or more, preferably 50 or more, and more preferably 100 or more. The upper limit of n is preferably 870 or less, more preferably 750 or less, and still more preferably 500 or less.

The ethylene- (meth) acrylic block copolymer may be used alone or in combination of two or more polymers having different R ₁ , R ₂ , R ₃ , m, or n.

The content of the constituent units derived from the olefin in the olefin-unsaturated carboxylic acid copolymer is preferably 60 to 99% with respect to the total of the constituent units derived from the olefin and the constituent units derived from the unsaturated carboxylic acid-based monomer. Mole%, more preferably 65 to 95 mole%, and even more preferably 80 to 95 mole%. In addition, the content of the constituent units derived from the unsaturated carboxylic acid monomer is preferably 1 to 40 mol% relative to the total of the constituent units derived from the olefin and the constituent units derived from the unsaturated carboxylic acid monomer. , More preferably 5 to 35 mole%, and still more preferably 5 to 20 mole%. When the content of the constituent unit derived from the olefin is 60 mol% or more, the copolymer has sufficient crystallinity and will melt efficiently during drilling processing, so the chip discharge is good, and the accuracy of the hole position is excellent. Or the tendency of drill bit breakage resistance to improve. On the other hand, when the content of the constituent unit derived from the unsaturated carboxylic acid-based monomer is 1 mol% or more, the stability when the copolymer is produced into an aqueous dispersion tends to be further improved.

In the above olefin- (meth) acrylic acid copolymer, the content of the constituent units derived from the olefin is preferably 60 to 99 mole% relative to the total of the constituent units derived from the olefin and the constituent units derived from the (meth) acrylic acid. Ear%, more preferably 65 to 95 mole%, and even more preferably 80 to 95 mole%. In addition, the content of the constituent units derived from (meth) acrylic acid is preferably 1 to 40 mol% relative to the total of 100 mol% of the constituent units derived from olefins and the constituent units derived from (meth) acrylic acid, and more preferably 5 ~ 35 mole%, and more preferably 5 ~ 20 mole%. When the content of the constituent unit derived from the olefin is 60 mol% or more, the copolymer has sufficient crystallinity and will melt efficiently during drilling processing, so the chip discharge is good, and the accuracy of the hole position is excellent. Or the tendency of drill bit breakage resistance to improve. On the other hand, when the content of the structural unit derived from (meth) acrylic acid is 1 mol% or more, the stability when the copolymer is produced into an aqueous dispersion tends to be further improved.

The content of constituent units derived from ethylene in the ethylene- (meth) acrylic acid copolymer represented by the above general formula (1) is 100 mol% relative to the total of constituent units derived from ethylene and constituent units derived from (meth) acrylic acid It is preferably 60 to 99 mole%, more preferably 65 to 95 mole%, and even more preferably 80 to 95 mole%. In addition, the content of the constituent units derived from (meth) acrylic acid is preferably 1 to 40 mol%, more preferably 100% by mole relative to the total of the constituent units derived from ethylene and the constituent units derived from (meth) acrylic acid. 5 ~ 35 mole%, and more preferably 5 ~ 20 mole%. When the content of the constituent unit derived from ethylene is 60 mol% or more, the copolymer has sufficient crystallinity, and it will melt efficiently during drilling processing, so the chip discharge is good, and the accuracy of the hole position is excellent. Or the tendency of drill bit breakage resistance to improve. On the other hand, when the content of the structural unit derived from (meth) acrylic acid is 1 mol% or more, the stability when the copolymer is produced into an aqueous dispersion tends to be further improved. In particular, the ratio (m: n) of the number of constituent units (m) derived from ethylene to the number of constituent units (n) derived from (meth) acrylic acid in the ethylene- (meth) acrylic copolymer is 80: 20 ~ 95 : 5, there is a tendency that the hole position accuracy is better when drilling.

When the ethylene- (meth) acrylic acid copolymer represented by the general formula (1) is an ethylene-acrylic acid copolymer, the content of the constituent units derived from ethylene is 100 moles relative to the total of the constituent units derived from ethylene and the constituent units derived from acrylic acid. Ear%, preferably 60 to 99 mole%, more preferably 65 to 95 mole%, and even more preferably 80 to 95 mole%. In addition, the content of the constituent units derived from acrylic acid is preferably 1 to 40 mol%, more preferably 5 to 35 mol% relative to the total of 100 mol% of the constituent units derived from ethylene and the constituent units derived from acrylic acid. More preferably, it is 5-20 mol%. When the content of the constituent unit derived from ethylene is 60 mol% or more, the copolymer has sufficient crystallinity, and it will melt efficiently during drilling processing, so the chip discharge is good, and the accuracy of the hole position is excellent. Or the tendency of drill bit breakage resistance to improve. On the other hand, when the content of the constituent unit derived from acrylic acid is 1 mol% or more, the stability when the copolymer is produced into an aqueous dispersion tends to be further improved. In particular, since the ratio (molar ratio) of the number of constituent units derived from ethylene to the number of constituent units derived from acrylic acid in the ethylene-acrylic acid copolymer is 80:20 to 95: 5, the hole position accuracy during drilling is more excellent. The tendency.

The weight average molecular weight of the polyolefin resin (A) is preferably 5 × 10 ³ or more and 1 × 10 ⁵ or less, more preferably 2 × 10 ⁴ or more and 8 × 10 ⁴ or less, and still more preferably 4 × 10 ⁴ or more 7 × 10 ⁴ the following. When the weight average molecular weight is 5 × 10 ³ or more, the adhesion of the auxiliary plates to each other (hereinafter, also simply referred to as “adhesion”) is more suppressed, and the operability of the auxiliary plates tends to be more improved. In addition, when the weight average molecular weight is 1 × 10 ⁵ or less, the dischargeability of cutting chips during drilling is improved, the accuracy of the hole position is further improved, and the breakage of the drill tends to be more suppressed. The weight average molecular weight of the polyolefin resin (A) can be measured using a GPC column according to a conventional method, and using polystyrene as a standard substance.

The content of the polyolefin resin (A) in the layer of the resin composition is determined by considering the position accuracy of the hole when using a drill with a diameter of 0.075 mm or less for drilling and the diameter of the fine diameter for drilling. It is stipulated from the viewpoint of the balance of the drill bit break resistance. The content of the polyolefin resin (A) is 15 mass parts or more and 25 mass parts or less based on 100 mass parts of the total of the polyolefin resin (A), the low-molecular-weight water-soluble lubricant (B), and the water-soluble resin (C). It is preferably 20 parts by mass or more and 25 parts by mass or less. When the content of the polyolefin resin (A) is 15 parts by mass or more, the adhesive strength of the layer of the metal foil and the resin composition is further improved. Therefore, the resin composition is caused by poor hole position accuracy and drill breakage during hole-opening processing. The peeling of the layer is more suppressed. Therefore, the accuracy of the hole position is improved, and the resistance to drill breakage is further improved. On the other hand, when the content of the polyolefin resin (A) is 25 parts by mass or less, the content of the low-molecular-weight water-soluble lubricant (B) and the water-soluble resin (C) in the layer of the resin composition can be adjusted to Achieving sufficient lubricity for drilling, the hole position accuracy and drill breakage resistance during drilling are excellent. In particular, when the content of the polyolefin resin (A) is 20 parts by mass or more and 25 parts by mass or less, the adhesive strength of the layer of the metal foil and the resin composition, the position accuracy of the hole during the drilling process, and the resistance to drill breakage are excellent. .

The manufacturing method of the polyolefin resin (A) which is a homopolymer is not specifically limited, A conventionally well-known method can be used. The method for producing the polyolefin resin (A) which is a copolymer is not particularly limited, and a method of polymerizing an olefin monomer and a comonomer by a conventionally known method can be used. For example, the method for producing the above-mentioned olefin-unsaturated carboxylic acid copolymer is not particularly limited, and an olefin monomer such as an ethylene monomer and a propylene monomer can be copolymerized with an unsaturated carboxylic acid monomer and produced.

(Low-molecular-weight water-soluble lubricant (B)) The content of the low-molecular-weight water-soluble lubricant (B) is relative to that of the polyolefin resin (A), the low-molecular-weight water-soluble lubricant (B), and the water-soluble resin (C). A total of 100 parts by mass is 5 to 40 parts by mass, preferably 10 to 35 parts by mass, more preferably 10 to 30 parts by mass. When the content of the low-molecular-weight water-soluble lubricant (B) is 5 parts by mass or more, the lubricity of the resin composition layer during the drilling process is further improved, and the hole position accuracy and / or the drill bit breakage resistance are further improved. When the content of the low-molecular-weight water-soluble lubricant (B) is 40 parts by mass or less, occurrence of blocking can be suppressed, and workability is further improved.

The weight-average molecular weight of the low-molecular-weight water-soluble lubricant (B) is preferably 6 × 10 ² or more and 2.5 × 10 ³ or less. When the weight-average molecular weight of the low-molecular-weight water-soluble lubricant (B) is 6 × 10 ² or more, the occurrence of blocking can be suppressed, and the workability tends to be further improved. With the weight-average molecular weight of the low-molecular-weight water-soluble lubricant (B) being 2.5 × 10 ³ or less, the lubricity of the layer with the resin composition is further improved, the accuracy of the hole position is further improved, and the resistance to drill breakage is further improved. tendency.

The low-molecular-weight water-soluble lubricant (B) is not particularly limited. For example, it is preferably one or two or more selected from the group consisting of polyethylene glycol, polytetramethylene glycol, and the like. Alcohol compounds; polyoxyethylene oleyl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, polyoxyethylene lauryl ether, polyoxyethylene nonylphenyl ether, polyoxyethylene octylphenyl ether, etc. Ether compounds; polyoxyethylene monolaurate, polyoxyethylene monostearate, polyoxyethylene monooleate, polyoxyethylene distearate, polyoxyethylene sorbitan monolaurate, polyoxyethylene Ethylene sorbitan monostearate, polyoxyethylene sorbitan monooleate, polyglycerol monostearate compounds, polyoxyethylene propylene copolymers, and their derivatives; more preferably polyoxyethylene monostearate Lauric acid ester, polyoxyethylene monostearate, polyoxyethylene monooleate, polyoxyethylene distearate, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monostearate Acid esters, polyoxyethylene sorbitan monooleate, and polyoxyethylene monostearate is preferred. These compounds may be used individually by 1 type, and may be used in combination of 2 or more type.

A commercially available low molecular weight water-soluble lubricant (B) can also be used. As a commercially available product of the low-molecular-weight water-soluble lubricant (B), NONION S15.4 (polyoxyethylene monostearate, weight average molecular weight 1,540) manufactured by Nippon Oil Co., Ltd. can be exemplified.

(Water-soluble resin (C)) The water-soluble resin (C) contains a high-molecular-weight water-soluble resin (c-1) and a medium-molecular-weight water-soluble resin (c-2). Such a water-soluble resin (C) is not particularly limited as long as it is a water-soluble resin, and is preferably selected from the group consisting of polyethylene oxide, polypropylene oxide, polyvinylpyrrolidone, cellulose derivatives, and polyethylene. Diols, polypropylene glycols, polytetramethylene glycols, monoether compounds of polyoxyethylene, polyoxyethylene monostearate, polyoxyethylene sorbitan monostearate, polyglycerol monostearate One or two or more of the group consisting of compounds, polyethylene oxide-polypropylene oxide copolymers, and their derivatives. By using such a water-soluble resin (C), the moldability of the layer of a resin composition and the effect as a lubricating material of an auxiliary board tend to improve more. The "water-soluble resin" means a resin that dissolves 1 g or more with respect to 100 g of water at 25 ° C and 1 atmosphere.

The content of the water-soluble resin (C) refers to the accuracy of the hole position when drilling with a drill with a fine diameter of 0.075 mm or less and the resistance to the breakage of the drill bit. Stipulated in terms of balance. The content of the water-soluble resin (C) is 35 mass parts or more and 80 mass parts or less based on 100 mass parts of the total of the polyolefin resin (A), the low-molecular-weight water-soluble lubricant (B), and the water-soluble resin (C). It is preferably 35 parts by mass or more and 60 parts by mass or less. When the content of the water-soluble resin (C) is 35 parts by mass or more, a layer of a uniform resin composition can be formed, and the layer of the resin composition can be provided with sufficient lubricity for drilling processing. Therefore, the accuracy of the hole position during drilling is further improved. On the other hand, when the content of the water-soluble resin (C) is 80 parts by mass or less, the content of the polyolefin resin (A) in the layer of the resin composition is increased accordingly, and as a result, the metal foil and the resin composition The adhesive strength of the layer is further improved, and the hole position accuracy and drill bit breakage resistance during drilling are excellent.

The type of the high-molecular-weight water-soluble resin (c-1) is not particularly limited, but is preferably selected from the group consisting of polyethylene oxide, polypropylene oxide, polyvinylpyrrolidone, and cellulose derivatives. One or two or more of them, and polyvinylpyrrolidone is particularly preferred. These compounds may be used individually by 1 type, and may be used in combination of 2 or more type. These compounds have plate-forming properties, so the use of these compounds can make the composition and thickness of the layer of the resin composition of the auxiliary plate for drilling processing of the present invention uniform.

If the weight average molecular weight of the high molecular weight water-soluble resin (c-1) is 6 × 10 ⁴ or more and 1.5 × 10 ⁶ or less, the film forming property of the resin composition layer when manufacturing the auxiliary plate for drilling processing is particularly good. It is more ideal.

The content of the high-molecular-weight water-soluble resin (c-1) in the layer of the resin composition is not particularly limited as long as it is within the range of the content of the water-soluble resin (C) in the layer of the resin composition. The total amount of the olefin resin (A), the low-molecular-weight water-soluble lubricant (B), and the water-soluble resin (C) is 100 parts by mass, preferably 5 parts by mass or more and 30 parts by mass, and more preferably 5 parts by mass or more and 20 parts by mass Hereinafter, it is more preferably 5 parts by mass or more and 10 parts by mass or less. When the content of the high-molecular-weight water-soluble resin (c-1) is within the above range, the layer of the resin composition can be provided with sufficient lubricity for drilling, and the adhesion strength of the layer having the metal foil and the resin composition is further improved. In order to improve, the hole position accuracy and drill breakage resistance during the drilling process tend to be excellent.

The aforementioned medium molecular weight water-soluble resin (c-2) is not particularly limited, and for example, a glycol compound such as polyethylene glycol, polypropylene glycol, polytetramethylene glycol can be used; polyoxyethylene oleyl ether, polyoxyethylene cetyl ether , Polyoxyethylene stearyl ether, polyoxyethylene lauryl ether, polyoxyethylene nonylphenyl ether, polyoxyethylene octylphenyl ether, and other polyoxyethylene monoether compounds; polyoxyethylene monostearate, polyoxyethylene Sorbitan monostearate, polyglycerol monostearate compounds, polyoxyethylene propylene copolymers, their derivatives, polyvinylpyrrolidone, and the like. These compounds and copolymers may be used individually by 1 type, and may be used in combination of 2 or more type. By using these compounds, the auxiliary plate for drilling processing of the present invention can sufficiently exhibit the lubricity effect during the drilling processing.

If the weight average molecular weight of the medium molecular weight water-soluble resin (c-2) is 3 × 10 ³ or more and 5 × 10 ⁴ or less, the effect of lubricity during drilling is excellent, which is preferable.

The content of the molecular weight water-soluble resin (c-2) in the layer of the resin composition is not particularly limited as long as it is within the range of the content of the water-soluble resin (C) in the layer of the resin composition. The total amount of the olefin resin (A), the low-molecular-weight water-soluble lubricant (B), and the water-soluble resin (C) is 100 parts by mass, preferably 35 parts by mass or more and 65 parts by mass, and more preferably 40 parts by mass or more and 60 parts by mass Hereinafter, it is more preferably 45 parts by mass or more and 60 parts by mass or less. When the content of the medium-molecular-weight water-soluble resin (c-2) is in the foregoing range, the adhesive strength of the layer of the metal foil and the resin composition, the hole position accuracy during the hole-cutting process, and the drill breakage resistance tend to be excellent.

The ratio of the content of the medium molecular weight water-soluble resin (c-2) to the content of the high molecular weight water-soluble resin (c-1) is preferably 3 to 10, more preferably 4 to 9, and still more preferably 5 to 8. It is preferably 5 ~ 7. When the ratio of the content of the medium-molecular-weight water-soluble resin (c-2) to the content of the high-molecular-weight water-soluble resin (c-1) is within the above range, the adhesive strength of the metal foil and the layer of the resin composition, and openings The balance of hole position accuracy and drill bit breakage resistance during processing tends to be more improved.

(Other components) The layer of the resin composition may contain additives if necessary. The type of the additive is not particularly limited, and examples thereof include a surface conditioner, a leveling agent, an antistatic agent, an emulsifier, an antifoaming agent, a wax additive, a coupling agent, a rheology control agent, a preservative, a mold inhibitor, and an anti- Oxidants, light stabilizers, nucleating agents such as sodium formate, organic fillers, inorganic fillers, thermal stabilizers, and coloring agents.

(Thickness of the layer of the resin composition) The thickness of the layer of the resin composition can be determined according to the diameter of the drill used in the drilling process and the object to be processed (such as a printed circuit board material such as a laminated board or a multilayer board). Etc. Choose appropriately. The thickness of the layer of such a resin composition is preferably 0.02 to 0.3 mm, and more preferably 0.02 to 0.2 mm. When the thickness of the layer of the resin composition is 0.02 mm or more, a more sufficient lubricating effect will be obtained, and the load on the drill bit will be reduced, so the tendency of the drill bit to break can be more suppressed. In addition, when the thickness of the layer of the resin composition is 0.3 mm or less, the resin composition can be prevented from being wrapped around the drill.

[Manufacturing method of auxiliary plate for drilling processing] The manufacturing method of auxiliary plate for drilling processing of this embodiment is not particularly limited, as long as it is a method for forming a layer of a resin composition on a metal foil, a general method may be used Manufacturing method.

The method for forming the layer of the resin composition is not particularly limited, and a known method can be used. Examples of such a method include dissolving or dispersing an aqueous dispersion of a polyolefin resin (A), a low-molecular-weight water-soluble lubricant (B), a water-soluble resin (C), and additives added as necessary in a solvent, The solution of the obtained resin composition is applied to a metal foil by a method such as a coating method, and then dried and / or cooled and solidified.

When a solution of a resin composition is coated on a metal foil by a coating method or the like and dried to form a layer of the resin composition, the solvent used in the solution of the resin composition is preferably a mixture of water and a lower boiling point than water. A mixed solution consisting of solvents. The use of a mixed solution composed of water and a solvent having a lower boiling point than water can effectively reduce residual air bubbles in the layer of the resin composition. The type of the solvent having a lower boiling point than water is not particularly limited, and examples thereof include alcohol compounds such as ethanol, methanol, and isopropanol, and low boiling point solvents such as methyl ethyl ketone and acetone may also be used. As for other solvents, solvents such as tetrahydrofuran and acetonitrile, which are highly compatible with the resin composition, are mixed in water and alcohol compounds.

In addition, the state of the polyolefin resin (A) when manufacturing an auxiliary plate for drilling processing, that is, the state of the polyolefin resin (A) when forming a layer of a resin composition is not particularly limited, and it is preferably an aqueous dispersion Like this. The manufacturing method of the aqueous dispersion of a polyolefin resin (A) is not specifically limited, A well-known method can be used. For example, a method of stirring other components such as the above-mentioned olefin-unsaturated carboxylic acid copolymer, an aqueous solvent, and optionally added alkalis, emulsifiers, etc. using a solid-liquid stirring device can be mentioned.

The alkali used when producing the aqueous dispersion of the polyolefin resin (A) is not particularly limited, and examples thereof include amine compounds such as ammonia, diethylamine, triethylamine, monoethanolamine, dimethylethanolamine, and diethylethanolamine, and hydroxide Alkali metal hydroxides such as sodium, potassium hydroxide, etc., but considering the compatibility with solvents when preparing a solution of a resin composition for forming a resin composition layer described later, ammonia, diethylamine, and triethylamine Monoethanolamine, dimethylethanolamine, and diethylethanolamine are preferred, and ammonia is particularly preferred.

The emulsifier used in the production of the aqueous dispersion of the polyolefin resin (A) is not particularly limited, and examples thereof include saturated fatty acids such as stearic acid, lauric acid, tridecanoic acid, myristic acid, and palmitic acid, and linolenic acid. Unsaturated fatty acids such as acid, linoleic acid, and oleic acid, but from the viewpoint of compatibility with aqueous solvents and oxidation resistance, stearic acid is preferred.

As the aqueous dispersion of the polyolefin resin (A), a commercially available product can also be used. As a commercially available product of an aqueous dispersion of a polyolefin resin (A), HITECH S3121 (ethylene-acrylic acid copolymer, weight average molecular weight 6 × 10 ⁴ ) produced by Toho Chemical Industry Co., Ltd. can be exemplified. The ratio of the number of constituent units derived from acrylic acid = 90: 10, with ammonia as the base and stearic acid as the emulsifier).

[Application] The use of the auxiliary plate for drilling in the present embodiment for drilling of a laminated board or a multilayer board is more effective and reliable in achieving the object of the present invention, so it is preferable. In addition, as for a laminated board, a "copper-clad laminated board" is generally used, but the laminated board of this embodiment may also be a "laminated board without a copper foil on the outer layer". In this embodiment, unless otherwise specified, a laminated board means a "copper-clad laminated board" and / or a "laminated board without a copper foil on the outer layer". In addition, if the drilling is performed by using a drill having a diameter (drill diameter) of 0.075 mmφ or less, the object of the present invention can be more effectively and reliably achieved. In particular, if the diameter is 0.05mmφ to 0.075mmφ or less, and even a small-diameter drill with a diameter of 0.05mmφ to 0.06mmφ becomes important, hole position accuracy and drill breakage resistance will be greatly improved. Sexuality is appropriate. In addition, the drill diameter of 0.05mmφ is the lower limit of the drill diameter that can be obtained, and there is no such limitation if a smaller diameter drill can be obtained. In addition, there is no problem even if the auxiliary plate for drilling is used in the drilling process using a drill having a diameter exceeding 0.075 mmφ.

The auxiliary board for drilling processing according to this embodiment can be applied, for example, when drilling a printed circuit board material, more specifically, a laminated board or a multilayer board. Specifically, the drilling process can be arranged at least on the top surface of the laminated board or multilayer board (printed circuit board material) obtained by overlapping one or more sheets, so that the metal foil side contacts the printed circuit board material. The auxiliary plate is used, and drilling is performed from the top surface (layer side of the resin composition) of the auxiliary plate.

[Drilling processing method] The drilling processing method of this embodiment has the following steps: using the above-mentioned auxiliary plate for micro-diameter drilling processing, and using a drilling machine for micro-diameter drilling processing with a diameter of 0.075 mm or less on a laminated plate or The multilayer board forms a hole. At this time, as shown in FIG. 1, the drilling rig 3 can be penetrated from the layer 1 side of the resin composition of the auxiliary plate for drilling processing, and the drilling rig 3 can be penetrated from the metal foil 2 side. [Example]

Hereinafter, the effects of the embodiments of the present invention will be described by comparing comparative examples that fall outside the scope of the present invention. In addition, "polyethylene glycol" is sometimes abbreviated as "PEG", and "polyethylene oxide" is sometimes abbreviated as "PEO".

Hereinafter, the methods for measuring the adhesion, the methods for measuring the accuracy of hole positions, and the methods for evaluating the resistance to drill breakage in the examples and comparative examples will be described.

<Evaluation of tackiness> The tackiness of the resin composition layer was evaluated as follows. The auxiliary plates for drilling processing prepared in the examples and comparative examples were arranged on the copper-clad laminated board so that the resin composition layer was on top, and 10,000 times of drilling processing was performed. The presence / absence of peeling of the resin composition layer after the drilling process was visually confirmed.

<Measurement of Hole Position Accuracy> The hole position accuracy was measured as follows. The auxiliary plates for drilling processing obtained in the examples and comparative examples were arranged on the overlapping copper-clad laminates so that the layers of the resin composition thereof were on top, and a predetermined number of drilling operations were performed. A hole analyzer (model: HA-1AM, manufactured by Hitachi viamechanics (Co., Ltd.)) was used to measure the maximum number of overlapping copper-clad laminates for all the drilled holes that were processed until the drill bit was broken in a predetermined number of drilled holes. The deviation between the hole position on the back (bottom) of the lower plate and the designated coordinates. For the amount of drilling per one drill bit, calculate the average and standard deviation (σ) for the deviation, and calculate "average + 3σ". Then, an average value of the values of each "average value + 3σ" is calculated for the n drills to be used as the hole position accuracy of the entire drilling process. The calculation formula used to calculate the hole position accuracy is as follows. [Number 1] (Here, n is the number of drill bits used.)

Regarding the accuracy of the hole position, if the number of holes to be processed increases in a predetermined number of holes, the abrasion of the front edge of the drill bit will increase and the core's coreness will decrease. The "average value + 3σ" tends to increase. Therefore, if the number of holes to be processed is small, that is, the resistance to drill breakage is poor, the accuracy of the hole position tends to decrease.

<Evaluation of bit break resistance> The bit break resistance was evaluated as follows. The auxiliary plates for drilling processing obtained in the examples and comparative examples were arranged on the overlapping copper-clad laminates so that the layers of the resin composition thereof were on top, and a predetermined number of drilling operations were performed. A hole analyzer (model: HA-1AM, manufactured by Hitachi viamechanics Co., Ltd.) was used to measure the number of drilled holes per drill until the drill was broken in a predetermined number of drilling operations, and calculated the average value. The value is defined as "number of machined holes". The formula used to calculate the number of processed holes is as follows. [Number 2] (Here, n is the number of drill bits used.)

The conditions for hole processing used to determine the hole position accuracy, number of holes processed, and resistance to drill breakage in the examples and comparative examples are as follows. The top surface of the copper clad laminate (trade name: HL832NS-L, copper foil thickness 5 μm, two panels, manufactured by Mitsubishi Gas Chemical Co., Ltd.) with 6 pieces of 0.04 mm thickness is arranged for drilling. Auxiliary plate with the resin composition layer side of the auxiliary plate as the top surface, and abutment plate (paper phenol laminated plate) with a thickness of 1.5 mm is arranged on the back (bottom surface) of the lowermost plate of the overlapped copper-clad laminated plate PS1160-G, made by Lichang Co., Ltd.). A 0.06 mmφ drill (manufactured by Uniontool Co., Ltd.) was used, and holes were opened at a rotation speed of 330,000 rpm and a delivery speed of 2.64 m / min. The drilling system uses 6 drills, and each drill has 10,000 holes. The hole position accuracy was evaluated for all the holes processed until the drill was broken out of 10,000 holes.

<Raw Materials> Table 1 shows the raw materials used in manufacturing the auxiliary plate for drilling in the working examples and comparative examples.

[Table 1]

Table 2 shows the specifications of the polyolefin resin (A). The polyolefin resin (A) is an aqueous dispersion, and the amount (mass%) of the resin solid content in the aqueous dispersion is as follows. The polyolefin resin (A) used is an ethylene-acrylic acid copolymer, and the ratio (m: n) of the number of constituent units (m) derived from ethylene to the number (n) of constituent units derived from (meth) acrylic acid, and The weight average molecular weight is shown below. The ratio (m: n) is calculated from the ¹ H-NMR method and the DQF-COSY method, which are nuclear magnetic resonance spectroscopic methods. The weight average molecular weight is measured by the method mentioned later.

[Table 2] ※ 1 m: n; the ratio of the number of constituent units (m) derived from ethylene to the number of constituent units (n) derived from (meth) acrylic acid

The weight-average molecular weights of the low-molecular-weight water-soluble lubricant (B) and the water-soluble resin (C) in Table 1 were measured by a method described later.

<Method for measuring weight average molecular weight of polyolefin resin (A)> The weight average molecular weight of polyolefin resin (A) is a liquid chromatograph equipped with a GPC column (manufactured by Shimadzu Corporation). Styrene was measured as a standard substance and calculated as a relative average molecular weight. The equipment and analysis conditions are shown below. (Used equipment) Shimadzu High-speed Liquid Chromatograph ProminenceLIQUID System controller: CBM-20A Infusion unit: LC-20AD Online degasser: DGU-20A3 Autosampler: SIL-20AHT column oven: CTO-20A Differential refraction Rate detector: RIO-10A LC workstation: LCSolution (analysis conditions) Columns: The following Phenomenex columns are connected in series in the following order: Phenogel 5μ 10E5A 7.8 × 300 × 1 Phenogel 5μ 10E4A 7.8 × 300 × 1 Phenogel 5μ 10E3A 7.8 × 300 × 1 guard column: Phenogel guard column 7.8 × 50 × 1 eluent: Tetrahydrofuran for high-speed liquid chromatography manufactured by Kanto Chemical Co., Ltd. Flow rate: 1.00mL / min Column temperature: 45 ° C (check Polystyrene for measuring line production) Showa Denko Shodex standard SL105, SM Weight average molecular weight of 105 standard polystyrene: 580,1390,2750,6790,13200,18500,50600,123000,259000,639000,1320000,2480000

<Method for measuring weight average molecular weight of low molecular weight water-soluble lubricant (B) and water-soluble resin (C)> The weight average molecular weight of low molecular weight water-soluble lubricant (B) and water-soluble resin (C) is based on GPC The liquid chromatography of the column (manufactured by Shimadzu Corporation) was measured using polyethylene glycol as a standard substance, and was calculated as a relative average molecular weight. The analysis conditions are shown below. The equipment used is the same equipment used for the weight average molecular weight measurement of the polyolefin resin (A). (Analytical conditions) Tubing: Connect the following Tosoh (stock) company-made tubular columns in series in the following order: TSK-GEL G3000PW (12) 7.5 × 300 × 2 TSK-GEL GMPW (17) 7.5 × 300 × 2 Column: TSKGUARDCOLUMN PWH 7.5 × 75 × 1 Dissolved liquid from Tosoh Corporation: 0.05mol / L sodium chloride aqueous solution (Mix sodium chloride with special grade manufactured by Guangshun Pharmaceutical Co., Ltd., and ion-exchanged water And preparation) flow rate: 1.00mL / min column temperature: 45 ° C (polyethylene glycol for calibration line production) Polyethylene Glycol Calibration Kit PEG-10 (polyethylene oxide for calibration line production) Tosoh ( The weight average molecular weight of TSK standard Poly (Ethylene oxide) standard polyethylene glycol and standard polyethylene oxide manufactured by the company: 106,615,1970,3930,7920,21030,43000,101000,185000,580,000

Hereinafter, a method for manufacturing an auxiliary plate for drilling in Examples and Comparative Examples will be described. <Example 1> An aqueous dispersion of a polyolefin resin (A) (trade name: HITECH S3121, manufactured by Toho Chemical Industry Co., Ltd., weight average molecular weight 6 × 10 ⁴ , m: n = 90: 10) 80 mass Parts (resin solid content is 20 parts by mass based on conversion), and polyoxyethylene monostearate (trade name: NONION S15.4, manufactured by Nippon Oil Corporation) as a low-molecular-weight water-soluble lubricant (B), Weight average molecular weight 1,540) 15.0 parts by mass of polyethylene oxide (trade name: Alkox E-45, manufactured by Meisei Chemical Industry Co., Ltd.) as a high molecular weight water-soluble resin (c-1), weight average molecular weight 5.6 × 10 ⁵ ) 8.0 parts by mass of 57.0 parts by mass of polyethylene glycol (trade name: PEG4000S, manufactured by Sanyo Chemical Industry Co., Ltd., a weight average molecular weight of 3.3 × 10 ³ ) as a medium molecular weight water-soluble resin (c-2) Methanol (manufactured by Mitsubishi Gas Chemical Co., Ltd.) to prepare a solution having a solid content concentration of 30% by mass of the resin composition. With respect to 100 parts by mass of the solid content of the resin composition in this solution, 1.2 parts by mass of a surface conditioner (BYK349, manufactured by BYK Chemie Japan Co., Ltd.) and 1.5 parts by mass of an antifoaming agent (BYK022, BYK Chemie Japan ( Co., Ltd.), and 0.17 parts by mass of sodium formate (manufactured by Mitsubishi Gas Chemical Co., Ltd.) was added to 100 parts by mass of the solid content of the resin composition in the solution, and uniformly dispersed to obtain a resin for forming the resin. A solution of a resin composition of the composition layer. The obtained resin composition solution was applied to an aluminum foil using a coating bar so that the thickness of the dried and cured resin composition layer was 0.05 mm (using aluminum foil: JIS-A1100H1.80, thickness 0.07 mm, Mitsubishi Aluminum (stock) company system). Next, it dried at 90 degreeC for 3 minutes using the dryer, it was made to cool and solidify, and the auxiliary board for drilling processing was obtained. The hole-cutting process was performed according to the above method, and the adhesion of the layer of the metal foil and the resin composition, the accuracy of the hole position, and the resistance to the breakage of the drill were evaluated. These results are shown in Table 3.

〈Examples 2 and 3〉 According to Example 1, a resin composition solution was prepared by using the types of raw materials and blending amounts shown in Table 3 to obtain a dried and cured resin composition layer having a thickness of 0.05 mm. Auxiliary plate for drilling. With respect to the obtained auxiliary plate for drilling processing, the adhesion of the layer of the metal foil and the resin composition, the accuracy of the hole position, and the resistance to the breakage of the drill were evaluated. These results are shown in Table 3.

<Comparative Examples 1 to 6> According to Example 1, a resin composition solution was prepared by using the types of raw materials and blending amounts shown in Table 3, and the thickness of the dried and cured resin composition layer was 0.05 mm. Auxiliary plate for drilling. With respect to the obtained auxiliary plate for drilling, the adhesion between the metal foil and the layer of the resin composition, the accuracy of the hole position, and the resistance to the breakage of the drill were evaluated. These results are shown in Table 3.

The criteria for determining the adhesion of the metal foil and the resin composition layer shown in Table 3 are as follows. Since a load is applied to the auxiliary plate during the drilling process, if the adhesion between the metal foil and the resin composition layer is weak, the resin composition layer will peel off. When peeling of the resin composition layer did not occur during drilling, it was marked as excellent "+++"; when peeling of the resin composition layer occurred, it was marked as "+".

The judgment criteria of the hole position accuracy shown in Table 3 are as follows. When the hole position accuracy calculated by the formula (1) is less than 14 μm, it is marked as excellent “+++”; when it is 14 μm or more and less than 15 μm, it is marked as good “++”; it is 15 μm or more If it cannot be processed, it will be marked as "+".

The judgment criteria for drill breakage resistance shown in Table 3 are as follows. When the number of processed holes calculated from the formula (2) is 9,000hits or more, it is marked as excellent "+++"; when it is 8,000hits or more and less than 9,000hits, it is marked as good "++"; If it is less than 8,000 hits, it will be marked as "+"; if it cannot be processed, it will be marked as "-".

The comprehensive judgment shown in Table 3 is as follows. The worst judgment among the adhesion judgment with the metal foil, the hole location accuracy judgment, and the drill bit breakage resistance judgment is taken as the comprehensive judgment.

[table 3]

As can be seen from Examples 1 to 3 in Table 3, if the content of the polyolefin resin (A) in the layer of the resin composition of the auxiliary plate for drilling is relative to the polyolefin resin (A) and the low-molecular-weight water-soluble lubricant ( B). If the total 100 parts by mass with the water-soluble resin (C) is 15 parts by mass to 25 parts by mass, and the content of the low-molecular-weight water-soluble lubricant (B) is 5 parts by mass or more and 40 parts by mass or less, drilling is performed. The metal foil of the auxiliary plate for processing and the layer of the resin composition have strong adhesive force, and the hole position accuracy and the drill bit break resistance of the auxiliary plate using the auxiliary plate are good.

On the other hand, from Comparative Examples 1 to 3, if the content of the polyolefin resin (A) in the layer of the resin composition is higher than that of the polyolefin resin (A), the low-molecular-weight water-soluble lubricant (B), and the water-soluble resin, (C) If the total 100 parts by mass is less than 15 parts by mass, the adhesion between the metal foil of the auxiliary plate for drilling and the layer of the resin composition is weak, and in the drilling process using the auxiliary plate, Peeling of the resin composition layer occurred, and drilling was impossible.

In Comparative Example 4 in which the content of the polyolefin resin (A) in the layer of the resin composition exceeded 25 parts by mass, the adhesion between the metal foil of the auxiliary plate for drilling and the layer of the resin composition was strong, but Even if the content of the low-molecular-weight water-soluble lubricant (B) with a lubricating effect is 5 mass parts or more and 40 mass parts or less, the lubricity of the resin composition layer has not been improved, and the cutting chip discharge performance during drilling is poor. Poor hole accuracy. In Comparative Example 5 in which the content of the polyolefin resin (A) was larger, the discharge of cutting chips during drilling was worse, and the drill break resistance was deteriorated. The hole position accuracy of Comparative Example 5 is smaller than that of Comparative Example 4. This is because the number of holes processed is small, and the wear of the drill tip has not increased, so that the hole position accuracy becomes smaller.

Further, in Comparative Example 6 which does not contain the low-molecular-weight water-soluble lubricant (B), the chip dischargeability during drilling was poor, the accuracy of the hole position was poor, and the resistance to drill breakage was also poor.

In summary, it can be seen that the content of the polyolefin resin (A) in the layer of the resin composition constituting the auxiliary plate for drilling is higher than that of the polyolefin resin (A), the low-molecular-weight water-soluble lubricant (B), and the water-soluble The total 100 parts by mass of the resin (C) is 15 parts by mass or more and 25 parts by mass or less. The content of the low-molecular-weight water-soluble lubricant (B) is higher than that of the polyolefin resin (A), the low-molecular-weight water-soluble lubricant (B), and If the total 100 parts by mass of the water-soluble resin (C) is 5 parts by mass or more and 40 parts by mass or less, and if the content of the water-soluble resin (C) is 35 parts by mass or more and 80 parts by mass or less, the metal of the auxiliary plate for drilling processing The layer of the foil and the resin composition has strong adhesive force, and the hole position accuracy and drill bit breakage resistance using the auxiliary plate are also good.

According to the present invention, it is possible to provide an auxiliary plate for drilling processing. Compared with the conventional auxiliary plate for drilling processing, the hole position accuracy during micro-diameter drilling is excellent, and the layer of the metal foil and the resin composition is peeled off. The occurrence of drill bit breakage is suppressed, and no necessary adhesive layer is required in the past, so the economy is also excellent.

This application is based on a Japanese patent application filed with the Japan Patent Office on June 1, 2017 (Japanese Patent Application No. 2017-109285), the contents of which are incorporated herein by reference. [Industrial availability]

The auxiliary plate for drilling processing of the present invention has industrial applicability for drilling processing of a laminated board or a multilayer board.

1‧‧‧ layer of resin composition

2‧‧‧ metal foil

3‧‧‧ Rig

[Fig. 1] It is a schematic diagram showing an aspect of an auxiliary plate for drilling processing and a method of drilling processing using the auxiliary plate according to this embodiment.

Claims (12)

Auxiliary plates for drilling with a micro diameter of 075 mm or less, comprising: a metal foil; and a polyolefin resin (A), a low-molecular-weight water-soluble lubricant (B), and a water-soluble component provided on at least one side of the metal foil A layer of a resin composition of a resin (C), the water-soluble resin (C) contains a high-molecular-weight water-soluble resin (c-1) and a medium-molecular-weight water-soluble resin (c-2), and the polyolefin resin (A) The low-molecular-weight water-soluble lubricant (B) and a total of 100 parts by mass of the water-soluble resin (C); the content of the polyolefin resin (A) is 15 parts by mass or more and 25 parts by mass or less; The content of the lubricant (B) is 5 parts by mass or more and 40 parts by mass or less, and the content of the water-soluble resin (C) is 35 parts by mass or more and 80 parts by mass or less. For example, the auxiliary plate for drilling a micro-diameter with a diameter of 0.075 mm or less in the first patent application scope, wherein the polyolefin resin (A) contains a constituent unit derived from an olefin and a constituent derived from acrylic acid and / or methacrylic acid. Unit olefin- (meth) acrylic copolymer. For example, the auxiliary plate for drilling a micro-diameter with a diameter of 0.075 mm or less in the second scope of the patent application, wherein the constituent unit derived from olefin contains a constituent unit derived from ethylene. For example, the auxiliary plate for drilling with a fine diameter of 0.075 mm or less in the second scope of the patent application, wherein the olefin- (meth) acrylic copolymer is an ethylene- (formaldehyde) having the structure of the following general formula (1) Group) acrylic block copolymer; (1) In formula (1), R ₁ , R ₂ , and R ₃ each independently represent a hydrogen atom or a methyl group, and m and n are each independently an integer of 1 or more. For example, the auxiliary plate for drilling with a fine diameter of 0.075 mm or less in the second scope of the patent application, wherein the content of the constituent unit derived from the olefin in the olefin- (meth) acrylic acid copolymer is relative to that derived from The total 100 mol% of the constituent unit of the olefin and the structural unit derived from the acrylic acid and / or the methacrylic acid is 60 to 99 mol%. For example, the auxiliary plate for drilling a micro-diameter with a diameter of 0.075 mm or less in the scope of the patent application No. 1 or 2, wherein the weight average molecular weight of the polyolefin resin (A) is 5 × 10 ³ or more and 1 × 10 ⁵ or less. For example, the auxiliary plate for drilling a micro-diameter with a diameter of less than 0.075 mm in the scope of the patent application No. 1 or 2, wherein the weight average molecular weight of the low-molecular-weight water-soluble lubricant (B) is 6 × 10 ² or more and 2.5 × 10 or more. ³ or less. For example, the auxiliary plate for drilling a micro-diameter with a diameter of less than 0.075 mm in the scope of application for patents 1 or 2, wherein the low-molecular-weight water-soluble lubricant (B) is selected from the group consisting of a monoether of a glycol compound and polyoxyethylene Compound, polyoxyethylene monolaurate, polyoxyethylene monostearate, polyoxyethylene monooleate, polyoxyethylene distearate, polyoxyethylene sorbitan monolaurate, polyoxyethylene One of the group consisting of sorbitan monostearate, polyoxyethylene sorbitan monooleate, polyglycerol monostearate compound, polyoxyethylene propylene copolymer, and their derivatives, or 2 or more. For example, the auxiliary plate for drilling a micro-diameter with a diameter of 0.075 mm or less in the first or second scope of the patent application, wherein the water-soluble resin (C) contains a material selected from the group consisting of polyethylene oxide, polypropylene oxide, and polyethylene. Pyrrolidone, cellulose derivatives, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, monoether compound of polyoxyethylene, polyoxyethylene monostearate, polyoxyethylene sorbitan monostearate One or two or more of the group consisting of an acid ester, a polyglycerol monostearate compound, a polyethylene oxide-polypropylene oxide copolymer, and their derivatives. For example, the auxiliary plate for drilling a micro-diameter with a diameter of 0.075 mm or less in the scope of application for the patent item 1 or 2, wherein the thickness of the layer of the resin composition is 0.02-0.3 mm. For example, if the auxiliary plate for drilling a micro-diameter with a diameter of 0.075 mm or less is in the scope of the first or second patent application, the thickness of the metal foil is 0.05 mm to 0.3 mm. A method for drilling a micro-diameter, having the following steps: using an auxiliary plate for micro-diameter drilling of 0.075 mm or less in diameter as in any one of the claims 1 to 11, and using a micro-diameter of 0.075 mm A drill for drilling is used to form holes in laminated or multilayer boards.