TWI712491B - Entry sheet for drilling, and drilling method using the same - Google Patents

Abstract

An entry sheet for drilling comprising a metal foil and a layer containing a resin composition comprising a polyurethane resin (A) and a water-soluble resin (B) that is formed on at least one surface of the metal foil without an interposed adhesion layer, wherein the amount of the polyurethane resin (A) in the layer containing the resin composition is 28 parts by mass or more and 60 parts by mass or less based on 100 parts by mass of the total of the polyurethane resin (A) and the water-soluble resin (B), and the polyurethane resin (A) is a copolymer having structural units derived from an alicyclic diisocyanate and structural units derived from an aliphatic polyol.

Description

Auxiliary board for drilling and drilling processing method using the auxiliary board

The present invention relates to an auxiliary board for drilling and a drilling method using the auxiliary board.

Regarding the drilling and processing method of laminated or multi-layer boards used in printed circuit board materials, the following method is generally adopted: stacking one or more laminates or multi-layer boards, and placing them at the top as abutting plates A single metal foil such as aluminum foil or a plate with a layer containing a resin composition formed on the surface of the metal foil (hereinafter, the "plate" in this specification is also referred to as "auxiliary board for drilling", or simply as "auxiliary Plate”), and carry out drilling.

In recent years, with the demand for improved reliability of printed circuit boards and the advancement of high density, the drilling of laminates or multilayer boards used in printed circuit boards also requires improved hole position accuracy and reduced hole wall roughness And other high-quality processing.

In order to meet the above-mentioned requirements such as improvement of hole position accuracy and reduction of hole wall roughness, for example, Patent Document 1 proposes a hole drilling method using a plate made of a water-soluble resin such as polyethylene glycol. In addition, Patent Document 2 proposes a lubricant sheet for opening in which a water-soluble resin layer is formed on a metal foil. Furthermore, Patent Document 3 proposes an auxiliary plate for openings in which a water-soluble resin layer is formed on an aluminum foil on which a thermosetting resin film has been formed. In addition, Patent Document 4 proposes a lubricant sheet for opening in which a non-halogen coloring agent is blended with a lubricant resin composition.

As one form of the auxiliary board for drilling, a form composed of a metal foil and a layer containing a resin composition formed on at least one side of the metal foil (hereinafter referred to as "resin composition layer") has been proposed. However, the adhesive strength between the metal foil and the resin composition layer is weak. Therefore, in the auxiliary board for drilling in which the metal foil and the resin composition layer are in direct contact, the resin composition layer is peeled from the metal foil during the drilling process, and the drill bit will follow the peeled resin composition layer, which often causes The deterioration of hole position accuracy and the deterioration of the break frequency of the drill. In addition, the auxiliary board for drilling is usually arranged on both sides of a multi-layered or multi-layered board, and then is subjected to drilling in a state in which these are formed into one bundle with a fixing tape. However, since the fixing tape is peeled from the bundle together with the resin composition layer, as a result, the position of the auxiliary plate may deviate. Therefore, in order to improve the adhesion strength between the metal foil and the resin composition layer in actual use, a urethane-based compound, a vinyl acetate-based compound, and a vinyl chloride-based compound are formed between the metal foil and the resin composition layer. An auxiliary plate is used in the form of an adhesive layer (adhesive film) composed of polyester compounds, polymers, epoxy compounds, cyanate ester compounds, and the like (for example, refer to Patent Document 5). [Prior Art Document] [Patent Document]

Patent Document 1: Japanese Patent Application Publication No. 4-92494 Patent Document 2: Japanese Patent Application Publication No. 5-169400 Patent Document 3: Japanese Patent Application Publication No. 2003-136485 Patent Document 4: Japanese Patent Application Publication No. 2004-230470 Patent Document 5: Japanese Patent Publication No. 2011-183548

[Problem to be Solved by the Invention] However, if an adhesive layer is provided between the metal foil and the resin composition layer as described in Patent Document 5, the adhesive layer hinders the lubricating effect of the resin composition. As a result, the hole position accuracy and hole wall roughness, which are important characteristics required for the auxiliary plate for drilling, may deteriorate. Therefore, it is desired to develop an auxiliary board for drilling that has strong adhesion strength between the metal foil and the resin composition layer, and excellent hole position accuracy and inner wall roughness, even though there is no adhesive layer between the metal foil and the resin composition layer. .

In view of such current situation, the subject of the present invention is to provide an auxiliary board for drilling, which is composed of a metal foil and a layer containing a resin composition formed on at least one side of the metal foil without interposing an adhesive layer. Moreover, the adhesion strength between the metal foil and the layer containing the resin composition is strong, and further, the hole position accuracy during drilling processing is excellent; and a drilling processing method using the auxiliary board is provided. [Means to solve the problem]

The inventors of the present application have conducted various studies in order to solve the above-mentioned problems. As a result, they found an auxiliary board for drilling, comprising: a metal foil and a layer containing a resin composition formed on at least one side of the metal foil without interposing an adhesive layer, and the layer containing the resin composition includes For the specific resin, the content of the specific resin is within a specific range; the adhesion strength between the metal foil and the layer containing the resin composition is strong, and further, the hole position accuracy during drilling is excellent, and the present invention has been completed.

That is, the present invention is as follows. [1] An auxiliary board for drilling, comprising: a metal foil, and a metal foil formed on at least one side of the metal foil without interposing an adhesive layer, including a polyurethane resin (A) and water-soluble The layer of the resin composition of the resin (B); the content of the polyurethane resin (A) in the layer containing the resin composition is relative to the polyurethane resin (A) and the water-soluble The total 100 parts by mass of the resin (B) is 28 parts by mass or more and 60 parts by mass or less, and the polyurethane resin (A) has structural units derived from alicyclic diisocyanates and structural units derived from aliphatic polyols的copolymer. [2] The auxiliary board for drilling of [1], wherein the content of the water-soluble resin (B) in the resin composition-containing layer is relative to the polyurethane resin (A) and the water-soluble resin The total 100 parts by mass of the resin (B) is 40 parts by mass or more and 72 parts by mass or less. [3] The auxiliary board for drilling according to [1] or [2], wherein the polyurethane resin (A) is composed of the structural unit derived from alicyclic diisocyanate and the aliphatic polyol The building blocks of the copolymer. [4] The auxiliary board for drilling according to any one of [1] to [3], wherein the alicyclic diisocyanate includes isophorone diisocyanate. [5] The auxiliary board for drilling as in [4], wherein the ratio of the structural unit derived from isophorone diisocyanate to the structural unit derived from aliphatic polyol possessed by the copolymer is calculated in moles , The number of moles of the structural unit derived from isophorone diisocyanate: The number of moles of the structural unit derived from aliphatic polyol is in the range of 3:97-9:91. [6] The auxiliary board for drilling according to any one of [1] to [5], wherein the number average molecular weight of the polyurethane resin (A) is 5000 or more and 50,000 or less. [7] The auxiliary board for drilling according to any one of [1] to [6], wherein the water-soluble resin (B) is selected from the group consisting of polyethylene oxide, polypropylene oxide, and polyvinyl Pyrrolidone, cellulose derivatives, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyoxyethylene monoether compounds, polyoxyethylene monostearate, polyoxyethylene sorbitan monostearic acid One or more of the group consisting of ester, polyglycerol monostearate, polyethylene oxide-polypropylene oxide copolymer, and derivatives thereof. [8] The auxiliary board for drilling according to [7], wherein the water-soluble resin (B) contains a polymer water-soluble resin (b1) having a weight average molecular weight of 50,000 or more and 1,500,000 Low-molecular weight-average molecular weight water-soluble resin (b2), the high-molecular water-soluble resin (b1) contains selected from the group consisting of polyethylene oxide, polypropylene oxide, polyvinylpyrrolidone, and cellulose derivatives At least one of the group, the low-molecular-weight water-soluble resin (b2) contains a monoether compound selected from polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyoxyethylene, and polyoxyethylene monomer At least one of the group consisting of stearate, polyoxyethylene sorbitan monostearate, polyethylene oxide-polypropylene oxide copolymer, and derivatives thereof. [9] The auxiliary board for drilling according to any one of [1] to [8], wherein the thickness of the layer containing the resin composition is 0.02 mm or more and 0.3 mm or less. [10] The auxiliary board for drilling according to any one of [1] to [9], wherein the thickness of the metal foil is 0.05 mm or more and 0.5 mm or less. [11] A drilling method, by arranging the auxiliary board for drilling as in any one of [1] to [10] on the top surface of a laminate or multilayer board, and using the drilling The top surface of the auxiliary board is drilled into the laminated board or multilayer board, and holes are formed in the laminated board or multilayer board. [Effects of Invention]

According to the present invention, it is possible to provide an auxiliary board for drilling, which is composed of a metal foil and a layer containing a resin composition formed on at least one side of the metal foil without interposing an adhesive layer, and the metal foil and The adhesive strength of the layer containing the resin composition is strong, and further, the hole position accuracy during drilling is excellent; and a drilling method using the auxiliary board can be provided.

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

[I: Auxiliary Board for Drilling] The auxiliary board for drilling of this embodiment is provided with a metal foil and is formed on at least one side of the metal foil without interposing an adhesive layer. It contains polyurethane Auxiliary board for drilling of the resin composition layer of ethyl resin (A) and water-soluble resin (B) (hereinafter referred to as "resin composition layer"), polyurethane in the resin composition layer The content of the ester resin (A) is 28 parts by mass or more and 60 parts by mass or less relative to the total 100 parts by mass of the polyurethane resin (A) and the water-soluble resin (B). The polyurethane resin ( A) It is a copolymer having a structural unit derived from an alicyclic diisocyanate and a structural unit derived from an aliphatic polyol.

The auxiliary board for drilling of this embodiment is composed of a metal foil and a resin composition layer formed on at least one side of the metal foil without interposing an adhesive layer. That is, there is no adhesive layer (resin film) for adhering the metal foil and the resin composition between the metal foil and the resin composition layer, and the metal foil and the resin composition layer are in direct contact. Since the resin composition layer contains polyurethane resin (A) and water-soluble resin (B), the content of polyurethane resin (A) in the resin composition layer is within the above range, and the polyamine Ethyl formate resin (A) is a copolymer having structural units derived from alicyclic diisocyanates and structural units derived from aliphatic polyols, even if there is no adhesive layer between the metal foil and the resin composition layer, the metal The adhesive strength between the foil and the resin composition layer is also strong, and the hole position accuracy during drilling is excellent.

The auxiliary board for drilling of this embodiment is economical in both the raw material and the manufacturing steps of the auxiliary board. That is, the auxiliary board for drilling of this embodiment does not require an adhesive layer to be interposed, so the cost of raw materials can be reduced, and there is no need to form an adhesive layer. Compared with the conventional auxiliary board for drilling, it is economical. Also excellent. The resin composition layer may be formed on one side of the metal foil, or may be formed on both sides. When the resin composition layer is formed on both sides, the composition of the resin composition in the layers may be the same or different.

[II: Polyurethane resin (A)] The polyurethane resin (A) contained in the resin composition layer of the auxiliary board for drilling of this embodiment has an alicyclic two A copolymer of the structural unit of isocyanate and the structural unit derived from aliphatic polyol. The copolymer is not particularly limited as long as it has a structural unit derived from an alicyclic diisocyanate and a structural unit derived from an aliphatic polyol as components.

The structural unit derived from the alicyclic diisocyanate refers to the structural unit (skeleton) derived from the alicyclic diisocyanate used as a raw material for the polymerization reaction when forming the polymer. The structural unit derived from the aliphatic polyol refers to the structural unit (skeleton) of the aliphatic polyol used as the raw material for the polymerization reaction when forming the polymer. That is, for the above-mentioned copolymer, at least the alicyclic diisocyanate providing the structural unit derived from the alicyclic diisocyanate and the aliphatic polyol providing the structural unit derived from the aliphatic polyol are copolymerized when forming the polymer The winner of the response.

Since the polyurethane resin (A) is a copolymer having a structural unit derived from alicyclic diisocyanate and a structural unit derived from aliphatic polyol, the auxiliary board for drilling of this embodiment includes metal foil and resin The adhesive strength of the composition layer is strong, and the hole position accuracy during drilling processing tends to be excellent. The reason is not particularly limited, but it is believed that the copolymer has structural units derived from alicyclic diisocyanate, so the adhesion strength between the metal foil and the resin composition layer becomes stronger, and it is mainly because the copolymer has a multi-component derived from aliphatic As the structural unit of alcohol, the resin composition layer has excellent lubricity, and therefore the hole position accuracy during drilling is excellent.

Provides an alicyclic diisocyanate derived from a structural unit of alicyclic diisocyanate, as long as it is an alicyclic organic compound having two isocyanate groups in the molecule, and is not particularly limited, and it may be a monomer or a polymer . Such compounds, for example, include isophorone diisocyanate, 1,3-diisocyanoxycyclohexane, 1,4-diisocyanoxycyclohexane, 4,4-dicyclohexylmethane Isocyanate, cyclohexylene diisocyanate, methylcyclohexylene diisocyanate, bis(2-isocyanoxyethyl)-4-cyclohexene-1,2-dicarboxylate, 2,5-norbornane Diisocyanate, and 2,6-norbornane diisocyanate. Among them, considering the viewpoint that the purpose of the embodiment can be more effectively and reliably achieved, isophorone diisocyanate, 1,3-diisocyanoxycyclohexane, and 1,4-diisocyanate are preferable Oxycyclohexane is more preferred, and isophorone diisocyanate is particularly preferred. These alicyclic diisocyanates may be used individually by 1 type, and may use 2 or more types together.

The aliphatic polyol that provides the structural unit derived from the aliphatic polyol is not particularly limited as long as it is an aliphatic organic compound having two or more hydroxyl groups in the molecule, and it may be a monomer or a polymer. Such compounds, for example, ethylene glycol, diethylene glycol, 1,3-propanediol, 1,2-propanediol, triethylene glycol, 2-methyl-1,3-propanediol, 2,2-diethylene glycol Methyl-1,3-propanediol, 2-butyl-2-ethyl-1,3-propanediol, 1,4-butanediol, 2-methyl-1,4-butanediol, 2-methyl -3-methyl-1,4-butanediol, 3-methyl-1,5-pentanediol, 1,5-pentanediol, 1,6-hexanediol, and 6-hydroxyadipate -1-hexyl ester (the reaction product of caprolactone and 1,6-hexanediol). Among these, considering the viewpoint that the purpose of the embodiment can be more effectively and reliably achieved, ethylene glycol, diethylene glycol, 1,4-butanediol, 1,6-hexanediol, and 6- Hydroxyadipate-1-hexanoate is preferred, and 1,6-hexanediol and 6-hydroxyadipate-1-hexanoate are particularly preferred. These aliphatic polyols may be used alone or in combination of two or more kinds.

The ratio of the structural unit derived from the alicyclic diisocyanate to the structural unit derived from the aliphatic polyol in the copolymer having the structural unit derived from the alicyclic diisocyanate and the structural unit derived from the aliphatic polyol is not particularly limited. The molar number of the structural unit of the alicyclic diisocyanate: the molar number of the structural unit derived from the aliphatic polyol is preferably in the range of 3:97-9:91. If the ratio of the molar number of the constituent units derived from the alicyclic diisocyanate to the total molar number 100 of the constituent units is 3 or more, the adhesion strength between the resin composition layer and the metal foil is more sufficient, and during drilling Since the resin composition layer becomes more difficult to peel off, there is a tendency that the hole position accuracy is more excellent. On the other hand, if the ratio of the molar number of the constituent units derived from the aliphatic polyol to the total molar number 100 of these constituent units is 91 or more, the lubricity during drilling becomes better, so the machining The discharge performance of the generated cutting chips is further improved, whereby there is a tendency that the hole position accuracy is more excellent, and/or the machining life of the drill bit becomes longer.

A copolymer having structural units derived from alicyclic diisocyanates and structural units derived from aliphatic polyols may contain structural units derived from alicyclic diisocyanates and aliphatic polyols within the scope that does not impair the purpose of this embodiment Structural units other than the structural units of the group polyol (hereinafter, also referred to as "other structural units" in this specification). That is, a copolymer having a structural unit derived from an alicyclic diisocyanate and a structural unit derived from an aliphatic polyol may also be an alicyclic diisocyanate that provides a structural unit derived from an alicyclic diisocyanate when forming a polymer , Provides aliphatic polyols derived from aliphatic polyol constituent units, and if necessary, provides a copolymer of other constituent units through copolymerization reaction. The other structural units are not particularly limited as long as they do not impair the purpose of this embodiment. Examples include oxalic acid, succinic acid, adipic acid, pimelic acid, sebacic acid, 1,2,4-butane tricarboxylic acid, 1,2,5-hexane tricarboxylic acid, 1,3-dicarboxy-2-methyl-2-methylene carboxypropane, 1,2-cyclohexane Alkane dicarboxylic acid, 1,3-cyclohexane dicarboxylic acid, 1,4-cyclohexane dicarboxylic acid, 1,2,4-cyclohexane tricarboxylic acid, tetrakis (methylene carboxyl) methane, and The structural unit of polycarboxylic acid such as 1,2,7,8-octatetracarboxylic acid; derived from ethylene, propylene, 1-butene, 2-butene, 1,3-butadiene, 1-pentene, 3- Structural units of olefins such as pentene, 1,3-pentadiene, and 1,5-pentadiene; and structural units derived from unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, and fumaric acid.

Among copolymers having structural units derived from alicyclic diisocyanates, structural units derived from aliphatic polyols, and other structural units, structural units derived from alicyclic diisocyanates, structural units derived from aliphatic polyols, and others The combination of structural units is not particularly limited. The content of other structural units in the copolymer having structural units derived from alicyclic diisocyanate, structural units derived from aliphatic polyols, and other structural units may be in a range that does not impair the purpose of this embodiment. It is not particularly limited. However, considering the viewpoint of achieving the purpose of the embodiment more effectively and reliably, the number of moles of structural units derived from alicyclic diisocyanate in the copolymer, the number of moles of structural units derived from aliphatic polyol, and When the total number of moles of other constituent units is 100 moles, it is preferably 1 to 5 moles.

Regarding the polyurethane resin (A), a copolymer having structural units derived from alicyclic diisocyanates, structural units derived from aliphatic polyols, and other structural units as necessary can be used alone. Two or more kinds can also be used.

In this embodiment, the polyurethane resin (A) is a copolymer composed of structural units derived from alicyclic diisocyanates and structural units derived from aliphatic polyols, that is, alicyclic diisocyanate-aliphatic Group polyol copolymer. If the polyurethane resin (A) is a copolymer composed of structural units derived from alicyclic diisocyanates and structural units derived from aliphatic polyols, the auxiliary board for drilling of this embodiment includes metal foil and resin The adhesive strength of the composition layer is stronger, and the hole position accuracy during the drilling process tends to be more excellent.

The copolymer composed of a structural unit derived from an alicyclic diisocyanate and a structural unit derived from an aliphatic polyol is not particularly limited. For example, the above-mentioned alicyclic diisocyanate which provides a structural unit derived from an alicyclic diisocyanate is mentioned , Copolymer obtained by copolymerization reaction with the above-mentioned aliphatic polyol providing structural units derived from aliphatic polyol. In the copolymer composed of the structural unit derived from the alicyclic diisocyanate and the structural unit derived from the aliphatic polyol, the combination of the structural unit derived from the alicyclic diisocyanate and the structural unit derived from the aliphatic polyol is not particularly limited. In addition, for the polyurethane resin (A), a copolymer composed of a structural unit derived from an alicyclic diisocyanate and a structural unit derived from an aliphatic polyol may be used alone or in combination of two The above is very useful.

The ratio of the structural unit derived from the alicyclic diisocyanate to the structural unit derived from the aliphatic polyol in the copolymer composed of the structural unit derived from the alicyclic diisocyanate and the structural unit derived from the aliphatic polyol is not particularly limited. The molar number of the structural unit derived from the alicyclic diisocyanate: the molar number of the structural unit derived from the aliphatic polyol is preferably in the range of 3:97-9:91. If the ratio of the molar number of the constituent units derived from the alicyclic diisocyanate to the total molar number 100 of the constituent units is 3 or more, the adhesion strength between the resin composition layer and the metal foil is more sufficient, and during drilling Since the resin composition layer becomes more difficult to peel off, there is a tendency that the hole position accuracy is more excellent. On the other hand, if the ratio of the molar number of the constituent units derived from the aliphatic polyol to the total molar number 100 of these constituent units is 91 or more, the lubricity during drilling becomes better, so the machining The discharge performance of the generated cutting chips is further improved, whereby there is a tendency that the hole position accuracy is more excellent, and/or the machining life of the drill bit becomes longer.

Considering the viewpoint of achieving the purpose of the embodiment more effectively and reliably, the alicyclic diisocyanate used in the synthesis of the polyurethane resin (A) should preferably include isophorone diisocyanate, which is preferably isophor Ketone diisocyanate is more preferred. More specifically, with regard to the polyurethane resin (A), the copolymer containing the structural unit derived from alicyclic diisocyanate and the structural unit derived from aliphatic polyol is preferably A copolymer of a structural unit of ketone diisocyanate and a structural unit derived from an aliphatic polyol is preferable. In addition, with regard to the polyurethane resin (A), the above-mentioned copolymer composed of structural units derived from alicyclic diisocyanates and structural units derived from aliphatic polyols is preferably composed of isophorone It is more preferable to form a copolymer composed of a constituent unit of a diisocyanate and a constituent unit derived from an aliphatic polyol, that is, it is more preferable to contain an isophorone diisocyanate-aliphatic polyol copolymer.

The isophorone diisocyanate-aliphatic polyol copolymer is not particularly limited. For example, it can be obtained by copolymerizing isophorone diisocyanate and the above-mentioned aliphatic polyol which provides the structural unit derived from the aliphatic polyol.的copolymer. Among them, isophorone diisocyanate-1,6-hexanediol copolymer, isophorone diisocyanate-6-hydroxyadipate-1-hexanyl ester copolymer, and isophorone diisocyanate-1 , 6-Hexanediol-6-hydroxyadipate-1-hexyl ester copolymer is preferred. Regarding the polyurethane resin (A), these copolymers may be used alone or in combination of two or more kinds. If the polyurethane resin (A) is a copolymer of these, the auxiliary board for drilling of this embodiment has better adhesion strength between the metal foil and the resin composition layer and the hole position accuracy during drilling tendency.

In a copolymer containing structural units derived from isophorone diisocyanate and structural units derived from aliphatic polyols, or copolymers consisting of structural units derived from isophorone diisocyanate and structural units derived from aliphatic polyols The ratio of the structural unit derived from isophorone diisocyanate to the structural unit derived from aliphatic polyol is not particularly limited. However, the ratio is preferably in the range of 3:97-9:91 in terms of the ratio of the number of moles of structural units derived from isophorone diisocyanate to the number of moles of structural units derived from aliphatic polyols Better. If the ratio of the number of moles of the constituent units derived from isophorone diisocyanate to the total number of moles of 100 of the constituent units is 3 or more, the adhesive strength between the resin composition layer and the metal foil is more sufficient, and the drilling process In this case, the resin composition layer becomes more difficult to peel off, and therefore there is a tendency that the hole position accuracy is more excellent. On the other hand, if the ratio of the molar number of the constituent units derived from the aliphatic polyol to the total molar number 100 of these constituent units is 91 or more, the lubricity during drilling becomes better, so the machining The discharge performance of the generated cutting chips is further improved, whereby there is a tendency that the hole position accuracy is more excellent, and/or the machining life of the drill bit becomes longer.

The content of the polyurethane resin (A) contained in the resin composition layer in the auxiliary board for drilling of this embodiment is relative to the polyurethane resin (A) and the water-soluble resin (B) described later. The total 100 parts by mass of) is 28 parts by mass or more and 60 parts by mass or less, preferably 30 parts by mass or more and 60 parts by mass or less, more preferably 35 parts by mass or more and 50 parts by mass or less. When the content of the polyurethane resin (A) is 28 parts by mass or more, the adhesion strength between the metal foil and the resin composition layer becomes more sufficient. As a result, peeling of the resin composition layer, which is a cause of poor hole position accuracy during drilling, and breakage of the drill bit, becomes less likely to occur, and therefore, there is a tendency that the hole position accuracy is more excellent and the drill bit processing life becomes longer. On the other hand, if the content of the polyurethane resin (A) is 60 parts by mass or less, the content of the water-soluble resin (B) in the resin composition layer can be adjusted so that the drilling process has more sufficient lubrication Due to the high performance, the hole position accuracy during drilling becomes more excellent. In particular, if the content of the polyurethane resin (A) is 28 parts by mass or more and 60 parts by mass or less relative to the total 100 parts by mass of the polyurethane resin (A) and the water-soluble resin (B) described later, there is The adhesion strength between the metal foil and the resin composition layer and the hole position accuracy during drilling tend to be more excellent.

The number average molecular weight of the polyurethane resin (A) is not particularly limited, but it is preferably 5,000 or more and 50,000 or less, and more preferably 20,000 or more and 50,000 or less. If the number average molecular weight is 5000 or more, the occurrence of blocking can be further suppressed, and there is a tendency that the operability becomes better. On the other hand, when the number average molecular weight is 50,000 or less, the discharge of cutting chips during drilling becomes better, thereby improving the accuracy of hole position and/or preventing drill breakage. The number average molecular weight of the polyurethane resin (A) can be measured according to a conventional method using a GPC column and polystyrene as a standard substance. More specifically, it can be measured according to the method described in the examples.

The production method and production conditions of the polyurethane resin (A) are not particularly limited, and known methods and conditions can be adopted. When the polyurethane resin (A) is an alicyclic diisocyanate-aliphatic polyol copolymer such as isophorone diisocyanate-aliphatic polyol copolymer, the above-mentioned isophorone diisocyanate, Alicyclic diisocyanates such as 1,3-diisocyanoxycyclohexane and 1,4-diisocyanoxycyclohexane, and ethylene glycol, diethylene glycol, 1,4-butanediol, Aliphatic polyols such as 1,6-hexanediol and 6-hydroxyadipate-1-hexanoate are produced by copolymerization by a known method. The raw materials that can be used in the production of polyurethane resin (A) are the above-mentioned alicyclic diisocyanates that provide structural units derived from alicyclic diisocyanates, and aliphatic polyvalents that provide structural units derived from aliphatic polyols Alcohols and compounds that can optionally provide other structural units within a range that does not impair the purpose of this embodiment.

The polyurethane resin (A) may also contain components such as raw materials, catalysts, and solvents used in the manufacture of the copolymer. In addition, it may also contain ingredients such as water and amine stabilizers and dispersants.

Regarding the polyurethane resin (A), when forming the resin composition layer in the auxiliary board for drilling of this embodiment, it is preferable to use it in the form of an aqueous dispersion. That is, the aspect of the polyurethane resin (A) when forming the resin composition layer is not particularly limited, and the aspect of an aqueous dispersion is preferable. The manufacturing method of the water dispersion of a polyurethane resin (A) is not specifically limited, A well-known method can be adopted. The production method of the water dispersion includes, for example, a method of stirring the above-mentioned polyurethane resin (A), an aqueous solvent, and other components such as an alkali and an emulsifier if necessary with a solid-liquid stirring device or the like.

Commercially available products can be used for the aqueous dispersion of the polyurethane resin (A). A commercially available product of an aqueous dispersion of polyurethane resin (A) can be exemplified by the product name "HYDRAN WLS210" (isophorone diisocyanate-1,6-hexanediol- manufactured by DIC Co., Ltd.) 6-Hydroxyadipate-1-hexyl ester copolymer, number average molecular weight: 35000, molar number of structural units derived from isophorone diisocyanate: ratio of molar number of structural units derived from aliphatic polyol = 6: 94).

[III: Water-soluble resin (B)] The water-soluble resin (B) contained in the resin composition layer of the auxiliary board for drilling of this embodiment is not particularly limited as long as it is a water-soluble resin. It is preferable to use high molecular water-soluble resin (b1) and low molecular water-soluble resin (b2). In addition, the "water-soluble resin" refers to a resin that dissolves at least 1 g with respect to 100 g of water at 25°C and 1 atmosphere.

The polymer water-soluble resin (b1) is not particularly limited. For example, it is preferably one selected from the group consisting of polyethylene oxide, polypropylene oxide, polyvinylpyrrolidone, and cellulose derivatives. Or two or more types are preferable. These compounds may be used individually by 1 type, and may be used in combination of 2 or more types. These compounds have particularly good sheet-forming properties, so by using these compounds, there is a tendency that the composition and thickness of the resin composition layer in the auxiliary plate for drilling of the present embodiment can be made more uniform. The weight average molecular weight of the polymer water-soluble resin (b1) is not particularly limited, but it is 50,000 or more and 1,500,000 or less, and it is preferable to further improve the film-forming properties of the resin composition layer when manufacturing the auxiliary board for drilling. Considering the same point of view, the weight average molecular weight is preferably 100,000 or more and 1,000,000 or less, and more preferably 200,000 or more and 800,000 or less. The weight average molecular weight can be measured by a general method such as liquid chromatography with a GPC column. In more detail, the polystyrene that is the standard substance used when making the calibration curve can be changed from those having various number average molecular weights to those having various weight average molecular weights. In addition, the number average in the following examples The method of measuring the molecular weight is carried out in the same manner, and the weight average molecular weight is measured (the same applies hereinafter).

The low-molecular water-soluble resin (b2) is not particularly limited. For example, it is preferably selected from glycol compounds such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol; polyoxyethylene oleyl ether, polyoxyethylene glycol, etc. Polyoxyethylene monoether compounds such as ethylene cetyl ether, polyoxyethylene stearyl ether, polyoxyethylene lauryl ether, polyoxyethylene nonylphenyl ether, and polyoxyethylene octylphenyl ether; polyoxyethylene monostearic acid One of the group consisting of ester, polyoxyethylene sorbitan monostearate, polyglycerol monostearate compound, polyethylene oxide-polypropylene oxide copolymer, and their derivatives Or two or more types are preferable. These compounds and copolymers may be used alone or in combination of two or more kinds. By using these compounds, the auxiliary plate for drilling of the present embodiment tends to exhibit the effect of lubricity more fully during drilling. The weight-average molecular weight of the low-molecular-weight water-soluble resin (b2) is not particularly limited, but if it is 1,000 or more and 30,000 or less, it is preferable to consider the point of further improvement in lubricity during drilling. Considering the same point of view, the weight average molecular weight is preferably 1,000 or more and 20,000 or less, and more preferably 1,500 or more and 10,000 or less. The weight average molecular weight can be measured by a general method such as liquid chromatography with a GPC column.

Among the above, the water-soluble resin (B) is preferably selected from polyethylene oxide, polypropylene oxide, polyvinylpyrrolidone, cellulose derivatives, polyethylene glycol, polypropylene glycol, and polytetrafluoroethylene. Methylene glycol, polyoxyethylene monoether compound, polyoxyethylene monostearate, polyoxyethylene sorbitan monostearate, polyglycerol monostearate, and polyethylene oxide- One or two or more of the group consisting of polypropylene oxide copolymers and their derivatives are preferable. By using such a water-soluble resin (B), there is a tendency that the film formability and hole position accuracy of the resin composition layer are more improved.

In particular, when the water-soluble resin (B) contains a high-molecular water-soluble resin (b1) having a weight average molecular weight of 50,000 or more and 1,500,000 or less, and a low-molecular water-soluble resin (b2) having a weight average molecular weight of 1,000 or more and 30,000 or less, The polymer water-soluble resin (b1) contains at least one selected from the group consisting of polyethylene oxide, polypropylene oxide, polyvinylpyrrolidone, and cellulose derivatives. b2) Containing monoether compounds selected from polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyoxyethylene, polyoxyethylene monostearate, polyoxyethylene sorbitan monostearic acid At least one of the group consisting of ester, polyethylene oxide-polypropylene oxide copolymer, and derivatives thereof is preferred. By using such a water-soluble resin (B), there is a tendency that the film formability and hole position accuracy of the resin composition layer are more improved.

The content of the water-soluble resin (B) in the resin composition layer is not particularly limited, but it is preferably 40 parts by mass or more relative to 100 parts by mass of the total of the polyurethane resin (A) and the water-soluble resin (B) 72 Parts by mass or less are preferable, more preferably 40 parts by mass or more and 70 parts by mass or less, and more preferably 50 parts by mass or more and 65 parts by mass or less. When the content of the water-soluble resin (B) is 40 parts by mass or more, a more uniform resin composition layer can be formed, and more sufficient lubricity can be imparted to the resin composition layer during drilling. As a result, the hole position accuracy at the time of drilling processing tends to be more excellent. On the other hand, if the content of the water-soluble resin (B) is 72 parts by mass or less, the content of the polyurethane resin (A) in the resin composition layer can be adjusted so that the metal foil and the resin composition layer are Since the adhesive strength is better, the hole position accuracy during drilling tends to be more excellent.

The content of the polymer water-soluble resin (b1) in the resin composition layer is not particularly limited as long as it is within the content range of the water-soluble resin (B) in the resin composition layer. However, the content is preferably 5 parts by mass or more and 30 parts by mass or less relative to the total 100 parts by mass of the polyurethane resin (A) and the water-soluble resin (B), more preferably 5 parts by mass or more and 10 parts by mass or less. Preferably, 5 parts by mass or more and 7 parts by mass or less are particularly preferred. When the content of the polymer water-soluble resin (b1) is within the above range, the film-forming properties and hole position accuracy of the resin composition layer tend to be more improved.

The content of the low molecular weight water-soluble resin (b2) in the resin composition layer is not particularly limited as long as it is within the content range of the water-soluble resin (B) in the resin composition layer. However, the content is preferably 40 parts by mass to 65 parts by mass relative to 100 parts by mass of the total of the polyurethane resin (A) and the water-soluble resin (B), more preferably 45 parts by mass to 65 parts by mass. Preferably, 45 parts by mass or more and 60 parts by mass or less are particularly preferred. When the content of the low-molecular-weight water-soluble resin (b2) is in the aforementioned range, there is a tendency that both the adhesion strength between the metal foil and the resin composition layer and the hole position accuracy during hole drilling are more excellent.

[IV: Other components] The resin composition layer in the auxiliary board for drilling of the present embodiment may contain additives within a range that does not impair the purpose of the present embodiment. The type of additives is not particularly limited. For example, surface regulators, leveling agents, antistatic agents, emulsifiers, antifoaming agents, wax additives, coupling agents, rheology control agents, preservatives, antifungal agents, Antioxidants, light stabilizers, nucleating agents such as sodium formate, solid lubricants such as graphite, organic fillers, inorganic fillers, heat stabilizers, and coloring agents. These may be used individually by 1 type, and may be used in combination of 2 or more types.

The thickness of the resin composition layer in this embodiment can be appropriately selected according to the diameter of the drill used in drilling, the structure of the object to be drilled (for example, a printed circuit board material such as a laminate or a multilayer board), etc. , So there is no special limit. However, the thickness should preferably be in the range of 0.02 mm or more and 0.3 mm or less, more preferably 0.02 mm or more and 0.2 mm or less, and more preferably 0.02 mm or more and 0.1 mm or less. When the thickness of the resin composition layer is 0.02 mm or more, a more sufficient lubricating effect can be obtained, and the load on the bit can be reduced, so there is a tendency to further suppress the breakage of the bit. In addition, since the thickness of the resin composition layer is 0.3 mm or less, there is a tendency to further suppress the winding of the resin composition around the drill.

[V: Metal foil] The metal foil contained in the auxiliary board for drilling of this embodiment is not particularly limited, but it is preferably a metal material that has high adhesion to the resin composition layer and can withstand the impact caused by the drill. Better. The type of metal of the metal foil is considered from the viewpoints of availability, cost, and workability, for example, aluminum. The material of the aluminum foil is preferably aluminum with a purity of 95% or more. Examples of such aluminum foil include 5052, 3004, 3003, 1N30, 1N99, 1050, 1070, 1085, and 8021 specified in JIS-H4160. By using aluminum foil with an aluminum purity of more than 95%, it can alleviate the impact caused by the drill bit, and further improve the penetration between the tip of the drill bit, and interact with the lubricating effect of the drill bit caused by the resin composition. The hole position accuracy of the machined hole is improved.

The thickness of the metal foil is not particularly limited, but is preferably 0.05 mm or more and 0.5 mm or less, and more preferably 0.05 mm or more and 0.3 mm or less. If the thickness of the metal foil is 0.05 mm or more, it is possible to more effectively suppress the generation of burrs in the object to be drilled during drilling (for example, printed circuit board materials such as laminated boards or multilayer boards). In addition, if the thickness of the metal foil is 0.5 mm or less, it becomes easier to discharge the chips generated during drilling.

The thickness of each layer constituting the auxiliary board for drilling of the present embodiment is measured as follows. First, use a profile polishing machine (manufactured by Japan Electronics Data Corporation, trade name "CROSS-SECTION POLISHER SM-09010") or an ultra-micro dicing knife (manufactured by Leica Corporation, product number "EM UC7"). Cut along the stacking direction of each layer. After that, using a SEM (Scanning Electron Microscope, such as KEYENCE's product number "VE-7800"), the cross section is observed from the direction perpendicular to the cut cross section, and the layers of the structure are measured For example, the thickness of the metal foil and resin composition layer is measured. The thickness of 5 locations was measured for one field of view, and the average value was used as the thickness of each layer.

As for the auxiliary board for drilling of this embodiment, the adhesive force between the resin composition layer and the metal foil measured by the method described in the following Examples is preferably 200 gf or more. In addition, the hole position accuracy measured according to the method described in the embodiments described later is preferably 18.0 μm or less.

[VI: Manufacturing method of auxiliary plate for drilling] The method of manufacturing the auxiliary plate for drilling of this embodiment is not particularly limited, and general manufacturing methods can be used. For example, the auxiliary board for drilling can be manufactured as follows. The auxiliary board for drilling of this embodiment is manufactured by forming a resin composition layer on at least one side of a metal foil. The method of forming a resin composition layer is not specifically limited, A well-known method can be adopted. As such a method, for example, a resin composition obtained by dissolving or dispersing an aqueous dispersion of a polyurethane resin (A), a water-soluble resin (B), and optionally added additives in a solvent The solution is coated on the metal foil by a method such as a coating method, and further dried, and/or cooled and solidified.

When the solution of the resin composition is coated on the metal foil by a coating method and the like is further dried to form the resin composition layer, the solvent used in the solution of the resin composition is preferably water and a boiling point lower than water A mixed solution composed of a solvent is preferred. By using a mixed solution composed of water and a solvent with a lower boiling point than water, the residual bubbles in the resin composition layer can be reduced more effectively. The type of 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 solvents such as methyl ethyl ketone and acetone can also be used. As for other solvents, it can be used as a solvent obtained by mixing a part of water and/or an alcohol compound with tetrahydrofuran and/or acetonitrile, which are highly compatible with the resin composition.

[VII: Drilling method] The drilling method of this embodiment has a hole forming step, which uses the above-mentioned auxiliary board for drilling to form holes in a laminate or multilayer board. More specifically, in the hole forming step, the auxiliary board for drilling is arranged on the top surface of the laminate or multilayer board, and the laminate or multilayer board is formed from the top surface of the auxiliary board for drilling. Drill holes and form holes in the laminate or multilayer board. In addition, if the drilling is done with a drill with a diameter (drill diameter) of 0.30 mmφ or less, the purpose of the present embodiment can be more effectively and reliably achieved. Especially for the use of drills with a diameter of 0.05mmφ or more and 0.30mmφ or less, and further use of small diameter drills with a diameter of 0.05mmφ or more and 0.20mmφ or less, which is important for hole position accuracy, it is more ideal to consider the point of greatly improving the hole position accuracy and drill life. . In addition, the drill bit diameter of 0.05mmφ is the lower limit of the drill bit diameter that can be obtained. If a drill with a smaller diameter is available, there is no such restriction. In addition, for drilling using a drill with a diameter of more than 0.30mmφ, the auxiliary board for drilling of this embodiment can also be used without problems. In addition, as for the laminated board, a copper-clad laminated board is generally used, and the laminated board of this embodiment may be a laminated board without copper foil on the outer layer. That is, in this embodiment, unless otherwise specified, the laminated board refers to a copper-clad laminated board and/or a laminated board without copper foil on the outer layer.

The auxiliary board for drilling of the present embodiment can be suitably used when, for example, a printed circuit board material, more specifically, a laminate or a multilayer board is drilled. Specifically, it is possible to arrange the auxiliary board for drilling on at least the top surface of one or more laminated boards or multilayer boards (for example, printed circuit board materials) stacked on the metal foil side to contact the printed circuit board material, And from the top surface of the auxiliary board (resin composition layer side) drilled.

As mentioned above, although this embodiment was demonstrated, this invention is not limited to this embodiment mentioned above. Various changes can be added to the present invention without departing from the gist of the invention. [Example]

Hereinafter, the examples of the present invention and the comparative examples falling outside the scope of the present invention will be compared and described. In addition, hereinafter "polyethylene glycol" is sometimes abbreviated as "PEG", and "polyethylene oxide" is sometimes abbreviated as "PEO".

Hereinafter, the measuring method of the adhesive force and the measuring method of the hole position accuracy in the Examples and Comparative Examples will be described. <Measurement method of adhesive force> The adhesive force is measured as follows. First, three samples were prepared by cutting the auxiliary boards for drilling produced in the Examples and Comparative Examples into a width of 3 mm and a length of 100 mm. Then, a double-sided tape is attached to the entire surface of the resin composition layer of the sample, and the sample is attached to a fixed table by the double-sided tape. After that, peel off 10mm between the resin composition layer and the metal foil from one end of the sample to which the double-sided tape is attached, and install a jig for installing the spring balance on the metal foil part of the peeled sample. Install a spring scale (manufactured by SANKO, with a maximum measurable value of 1000 gf) on the jig and stretch it at a speed of 1 cm/sec in a direction 180° relative to the attached surface, and read the index value of the spring scale. The measurement was performed on 3 samples, and the average value of the addition of 3 times was used as the value of the adhesive force. When there is no peeling between the metal foil and the resin composition layer, it is marked as ">1000".

<Measurement of hole position accuracy> The hole position accuracy is measured as follows. The top surface of the copper-clad laminate (trade name: HL832, copper foil thickness: 12μm, double-sided board, manufactured by Mitsubishi Gas Chemical Co., Ltd.) with a thickness of 0.2mm (trade name: HL832, copper foil thickness: 12μm) The auxiliary board for drilling produced in the Examples and Comparative Examples had the resin composition layer side as the top surface. Furthermore, a 1.5mm thick abutment board (paper-phenol laminated board, trade name "PS1160-G", manufactured by Lee Cheong Co., Ltd.) is placed on the back (bottom surface) of the lowermost board of the stacked copper clad laminate ). A 0.2mmφ drill bit (trade name: C-CFU020S, manufactured by Tungaloy Co., Ltd.) was used to perform a total of 6000 holes under the conditions of rotation speed: 200,000 rpm, delivery speed: 2.6 m/min, and number of holes: 3,000 holes per drill bit. Drilling processing.

(此處，n表示所使用之鑽頭的根數。)The holes of the 3000th hole (the first drill bit) and the 6000th hole (the second drill bit) are measured in stack using a hole analyzer (model: HA-1AM, manufactured by Hitachi-Via-Mechanics Co., Ltd.) The deviation between the hole position on the back (bottom) of the bottom plate of the copper clad laminate and the specified coordinates. For the component of one drill bit, calculate the average value and standard deviation (σ) for the deviation, and calculate the "average value + 3σ". After that, as the hole position accuracy of the entire drilling process, calculate the average value of each "average value + 3σ" for the two drills used. The formula used to calculate the accuracy of the hole position is as follows (1). 【Number 1】

(Here, n represents the number of drill bits used.)

<Raw materials> Table 1 shows the main specifications of polyurethane resin (A), water-soluble resin (B), additives, solvents, and metal foil used in the manufacture of auxiliary boards for drilling in the examples and comparative examples And manufacturers.

【Table 1】

Table 2 shows the details of the polyurethane resin (A) used in the Examples and Comparative Examples. The ratio (mole ratio) of the number of moles of structural units derived from diisocyanate to the number of moles of structural units derived from polyols in Table 2 is based on the ¹ H-NMR method and DQF- which are one of nuclear magnetic resonance spectroscopy methods. Calculated by COSY method. The number average molecular weight is measured by the method mentioned later. Regarding the resin solid content concentration, the polyurethane resin (A) used in the form of an aqueous dispersion is the amount (mass%) of the resin solid content in the aqueous dispersion.

【Table 2】

The resin of the trade name "HYDRAN WLS210" is a cycloaliphatic diisocyanate-aliphatic polyol copolymer, which is an isophorone diisocyanate-aliphatic polyol copolymer. The constituent units derived from diisocyanate in the copolymer are derived from isophorone diisocyanate, and the constituent units derived from aliphatic polyol are derived from 1,6-hexanediol and 6-hydroxyadipate-1-hexanol Ester (the reaction product of caprolactone and 1,6-hexanediol). Regarding the isophorone diisocyanate-aliphatic polyol copolymer, the structural unit derived from the diisocyanate has a structure of an aliphatic cyclic hydrocarbon (alicyclic ring) instead of an aromatic ring.

The ratio of the number of moles of constituent units derived from diisocyanate to the number of moles of constituent units derived from aliphatic polyol (the ratio of constituent units derived from diisocyanate to constituent units derived from aliphatic polyol) is the ratio of constituent units derived from diisocyanate Mole number of constituent unit: Mole number of constituent unit derived from aliphatic polyol=6:94. In this case, the molar number of the structural unit derived from the aliphatic polyol is the molar number of the structural unit derived from 1,6-hexanediol, and the molar number of the structural unit derived from 6-hydroxyadipate-1- The total number of moles of the constituent units of hexyl ester.

The resin of the trade name "SUPER FLEX 820" is an aromatic diisocyanate-aliphatic polyol copolymer, which is 2,4-toluene diisocyanate-aliphatic polyol copolymer. The structural unit derived from diisocyanate in the copolymer is derived from 2,4-toluene diisocyanate, and the structural unit derived from aliphatic polyol is derived from 3-methyl-1,5-pentanediol, 1,4-ring Hexane, dimethanol and triethylene glycol. Regarding the 2,4-toluene diisocyanate-aliphatic polyol copolymer, the structural unit derived from the diisocyanate has an aromatic ring (the structure of an aromatic cyclic hydrocarbon).

The ratio of the number of moles of structural units derived from diisocyanate to the number of moles of structural units derived from aliphatic polyol is the number of moles of structural units derived from diisocyanate: the number of moles of structural units derived from aliphatic polyol =28:72. In this case, the molar number of the structural unit derived from the aliphatic polyol is the molar number of the structural unit derived from 3-methyl-1,5-pentanediol, which is derived from the 1,4-ring The total of the number of moles of the structural unit of hexane dimethanol and the number of moles of the structural unit derived from triethylene glycol.

The resin of the trade name "HYDRAN APX101H" is an aliphatic diisocyanate-aromatic polyol copolymer, which is a hexamethylene diisocyanate-aromatic polyol copolymer. The structural unit derived from the diisocyanate in the copolymer is derived from hexamethylene diisocyanate, and the structural unit derived from the aromatic polyol is derived from the diethylene glycol-terephthalic acid copolymer. Regarding the hexamethylene diisocyanate-aromatic polyol copolymer, the structural unit derived from the diisocyanate does not have an alicyclic ring, and the structural unit derived from the aromatic polyol has an aromatic ring. The ratio of the number of moles of structural units derived from diisocyanate to the number of moles of structural units derived from aromatic polyol is the number of moles of structural units derived from diisocyanate: the number of moles of structural units derived from aromatic polyol = 7:93.

<Method for measuring the number average molecular weight of polyurethane resin (A)> The number average molecular weight of polyurethane resin (A) is measured by liquid chromatography with a GPC column (Shimadzu Corporation ( (Stock) made by the company), measured with polystyrene as a standard material, and calculated as a relative average molecular weight. The following shows the equipment used and analysis conditions. [Use equipment] Shimadzu high-performance liquid chromatography ProminenceLIQUID system controller: CBM-20A infusion unit: LC-20AD online degasser: DGU-20A3 autosampler: SIL-20AHT column oven: CTO-20A differential refraction Rate detector: RID-10A LC workstation: LCSolution [Analysis conditions] Column: Phenogel 5μ 10E5A 7.8×300×1, Phenogel 5μ 10E4A 7.8×300×1, Phenogel 5μ 10E3A 7.8×300×1, made by Phenomenex Guard column: Phenogel guard column 7.8×50×1, Phenomenex eluent: tetrahydrofuran Kanto Chemical Co., Ltd. for HPLC Flow rate: 1.00mL/min Column temperature: 45°C <detection volume Polystyrene for thread production> Shodex standard SL105, SM105 manufactured by Showa Denko Polystyrene with number average molecular weight 580, 1390, 2750, 6790, 13200, 18500, 50600, 123000, 259000, 639000, 1320,000, 2.480000

Hereinafter, the manufacturing method of the auxiliary board for drilling in an Example and a comparative example is demonstrated. <Example 1> An aqueous dispersion of isophorone diisocyanate-aliphatic polyol copolymer (trade name: HYDRAN WLS210, number average molecular weight: 35000, derived from isophorone diisocyanate-aliphatic polyol copolymer) as polyurethane resin (A) Number of moles of structural units of phorone diisocyanate: number of moles of structural units derived from aliphatic polyol=6:94, resin solid content concentration: 35% by mass, manufactured by DIC Corporation) 105 parts by mass ( 30 parts by mass in terms of resin solid content), polyethylene oxide as a polymer water-soluble resin (b1) (trade name: ALKOX E-45, weight average molecular weight: 560,000, manufactured by Mingcheng Chemical Industry Co., Ltd.) 7.0 parts by mass and 63.0 parts by mass of polyethylene glycol (trade name: PEG4000S, weight average molecular weight: 3300, manufactured by Sanyo Chemical Co., Ltd.) as a low-molecular-weight water-soluble resin (b2) dissolved in a water/methanol mixed solvent (Mass ratio 50/50) A solution with a solid content concentration of the resin composition of 30% by mass was prepared.

With respect to 100 parts by mass of the solid content of the resin composition in the solution, 1.2 parts by mass of a surface conditioner (BYK349, manufactured by BYK-Japan Co., Ltd.) was added, and further, with respect to 100 parts by mass of the solid content of the resin composition in the solution Parts, 0.25 parts by mass of sodium formate (manufactured by Mitsubishi Gas Chemical Co., Ltd.) was added and dispersed uniformly to obtain a resin composition solution for forming a resin composition layer.

Coat the obtained resin composition solution with a coating bar on the aluminum foil used as metal foil (use aluminum foil: JIS-A1100H1.80, thickness: 0.1mm, manufactured by Mitsubishi Aluminum Co., Ltd.), and dry and cure the resin The thickness of the composition layer becomes 0.05 mm. Then, it was dried at 120° C. for 3 minutes using a dryer, and then cooled and solidified to produce an auxiliary board for drilling.

The adhesion force between the metal foil and the resin composition layer of the drilling auxiliary board was measured for three times by the above method, and the added average value was obtained. In addition, drilling was performed in the above-mentioned method, and the hole position accuracy was measured. The results are shown in Table 3.

<Examples 2 to 5> According to the method described in Example 1, a resin composition solution was prepared according to the types and blending amounts of the raw materials shown in Table 3, and the thickness of the resin composition layer after drying and curing was A 0.05mm auxiliary board for drilling. For the obtained auxiliary board for drilling, the adhesion between the metal foil and the resin composition layer and the hole position accuracy during drilling were measured. The results are shown in Table 3.

<Comparative Examples 1 to 6> According to the method described in Example 1, a resin composition solution was prepared according to the types and blending amounts of the raw materials shown in Table 3, and the thickness of the resin composition layer after drying and curing was A 0.05mm auxiliary board for drilling. For the obtained auxiliary board for drilling, the adhesion between the metal foil and the resin composition layer and the hole position accuracy during drilling were measured. The results are shown in Table 3.

<Judgment Criteria> The adhesion criteria shown in Table 3 are as follows. The load during drilling and processing is applied to the auxiliary plate, so if the adhesion between the metal foil and the resin composition layer is weak, the resin composition layer may peel off. As a result of diligent research by the inventors of the present case, it was found that if the adhesive force is 200 gf or more, the resin composition layer does not peel off during drilling. Therefore, in terms of the criterion for judging adhesion, if it is 200gf or more, it is judged as "A", and if it is less than 200gf, it is judged as "B".

The judgment criteria of the hole position accuracy shown in Table 3 are as follows. When the hole position accuracy calculated by the above formula (1) is 18 μm or less, it is marked as "A" with excellent characteristics, and when it is larger than 18 μm, it is marked as "B".

The criteria for the comprehensive judgment shown in Table 3 are as follows. If both the adhesion force judgment result and the hole position accuracy judgment result are "A", the adhesion between the metal foil and the resin composition layer is strong, and the hole position accuracy is excellent, so the comprehensive judgment mark is "A", the hole position When at least one of the accuracy judgment result and the adhesion judgment result is "B", the comprehensive judgment is marked as "B".

＜黏著力判定基準＞ 200gf以上：A 未達200gf：B ＜孔位置精度判定基準＞ 18μm以下：A 超過18μm：B ＜綜合判定的基準＞ 黏著力判定結果及孔位置精度判定結果之兩者為A：A 黏著力判定結果及孔位置精度判定結果中之至少一者為B：B【table 3】

<Adhesion Judgment Criteria> 200gf or more: A less than 200gf: B <Hole Position Accuracy Judgment Criteria> 18μm or less: A over 18μm: B <Comprehensive Judgment Criteria> Both of the adhesion judgment result and the hole position accuracy judgment result are A: A. At least one of the adhesion force judgment result and the hole position accuracy judgment result is B: B

From the results of Examples 1 to 5 shown in Table 3, it can be seen that the polyurethane resin (A) in the resin composition layer of the auxiliary board for drilling has structural units derived from alicyclic diisocyanate and The copolymer of the constituent units of aliphatic polyol, the content of the polyurethane resin (A) is 30 mass parts relative to the total 100 parts by mass of the polyurethane resin (A) and the water-soluble resin (B) If it is 60 parts by mass or more, the adhesion between the metal foil and the resin composition layer of the auxiliary plate for drilling is strong, and the hole position accuracy of the drilling process of the auxiliary plate is also good.

On the other hand, from the results of Comparative Examples 1 and 2, it can be seen that even if the polyurethane resin (A) in the resin composition layer is composed of structural units derived from alicyclic diisocyanate and aliphatic polyols The copolymer of the unit, if the content of the polyurethane resin (A) is less than 30 parts by mass relative to the total 100 parts by mass of the polyurethane resin (A) and the water-soluble resin (B), The adhesion between the metal foil of the auxiliary board for drilling and the resin composition layer is still weak. In addition, by the drilling of the auxiliary plate, the resin composition layer was peeled off, and the hole position accuracy was deteriorated.

Furthermore, in Comparative Examples 3 to 5, the structural unit derived from diisocyanate in the polyurethane resin (A) is a structural unit derived from an aromatic diisocyanate, and is not a structural unit derived from an alicyclic diisocyanate. In these Comparative Examples 3 to 5, even if the content of the polyurethane resin (A) in the resin composition layer is 100% relative to the total of the polyurethane resin (A) and the water-soluble resin (B) The part by mass is 30 parts by mass or more and 60 parts by mass or less. Although the adhesion between the metal foil of the auxiliary plate for drilling and the resin composition layer is strong, the accuracy of the hole positions processed by the auxiliary plate is poor. The reason is that due to the high cohesive force of the urethane bond from the aromatic diisocyanate and the high rigidity of the aromatic ring, the resin composition layer in the auxiliary board lacks lubricity.

Moreover, in Comparative Example 6, the diisocyanate unit in the polyurethane resin (A) is a structural unit derived from an aliphatic diisocyanate without alicyclic ring, and the polyol unit is a structural unit derived from an aromatic polyol. In this comparative example 6, even if the content of the polyurethane resin (A) in the resin composition layer is 100 parts by mass relative to the total of the polyurethane resin (A) and the water-soluble resin (B) 30 parts by mass to 60 parts by mass, the resin composition layer of the auxiliary plate still lacks lubricity, and the hole position accuracy of the drilling process of the auxiliary plate is poor. The reason is the high cohesive force and high rigidity of the aromatic ring due to the urethane bond of the aromatic polyol.

From the above conclusion, it can be seen that the content of polyurethane resin (A) in the resin composition layer constituting the auxiliary board for drilling is relative to the difference between the polyurethane resin (A) and the water-soluble resin (B) If the total 100 parts by mass is 28 parts by mass or more and 60 parts by mass or less, and the polyurethane resin (A) is a copolymer having structural units derived from alicyclic diisocyanates and structural units derived from aliphatic polyols, drill The adhesion between the metal foil and the resin composition layer in the auxiliary plate for holes is strong, and the hole position accuracy in the drilling process using the auxiliary plate is also good.

According to the present embodiment, it is possible to provide an auxiliary board for drilling. Compared with the conventional auxiliary board for drilling, the hole position accuracy is excellent, and the occurrence of drill breakage due to peeling between the metal foil and the resin composition layer is affected. It is suppressed and does not require an adhesive layer that was necessary in the past, so the economy is also excellent.

This application is based on a Japanese patent application (Japanese Patent Application 2016-047989) filed on March 11, 2016, the content of which is incorporated herein for reference. [Industrial availability]

The present invention can provide a drilling auxiliary board composed of a metal foil and a layer containing a resin composition formed on at least one side of the metal foil without interposing an adhesive layer, the metal foil and the resin composition containing layer The adhesive strength of the layer is strong, and the hole position accuracy during drilling is excellent. Therefore, the present invention has industrial applicability in such a field.

Claims (11)

An auxiliary board for drilling, comprising: a metal foil; and a metal foil formed on at least one side of the metal foil without interposing an adhesive layer and including a polyurethane resin (A) and a water-soluble resin (B ) The layer of the resin composition; the content of the polyurethane resin (A) in the layer containing the resin composition is relative to the polyurethane resin (A) and the water-soluble resin (B The total 100 parts by mass of) is 28 parts by mass or more and 60 parts by mass or less. The polyurethane resin (A) is a copolymer having structural units derived from alicyclic diisocyanate and structural units derived from aliphatic polyols . For example, the auxiliary board for drilling of item 1 of the scope of patent application, wherein the content of the water-soluble resin (B) in the layer containing the resin composition is relative to the polyurethane resin (A) and the water-soluble The total 100 parts by mass of the resin (B) is 40 parts by mass or more and 72 parts by mass or less. For example, the auxiliary board for drilling of item 1 or 2 of the scope of patent application, wherein the polyurethane resin (A) is composed of the constituent unit derived from alicyclic diisocyanate and the aliphatic polyol Copolymers composed of units. For example, the auxiliary board for drilling according to item 1 or 2 of the scope of patent application, wherein the alicyclic diisocyanate includes isophorone diisocyanate. For example, the auxiliary board for drilling according to item 4 of the scope of patent application, wherein the ratio of the structural unit derived from isophorone diisocyanate and the structural unit derived from aliphatic polyol possessed by the copolymer is calculated in moles , The molar number of the structural unit derived from isophorone diisocyanate: the molar number of the structural unit derived from aliphatic polyol is in the range of 3:97-9:91. For example, the auxiliary board for drilling of item 1 or 2 of the scope of patent application, wherein the number average molecular weight of the polyurethane resin (A) is 5000 to 50000. For example, the auxiliary board for drilling of item 1 or 2 of the scope of patent application, wherein the water-soluble resin (B) is selected from polyethylene oxide, polypropylene oxide, polyvinylpyrrolidone, and cellulose derivatives , Polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyoxyethylene monoether compound, polyoxyethylene monostearate, polyoxyethylene sorbitan monostearate, polyglycerol monostearate One or more of the group consisting of fatty acid ester, polyethylene oxide-polypropylene oxide copolymer, and their derivatives. For example, the auxiliary board for drilling of item 7 of the scope of patent application, wherein the water-soluble resin (B) contains a polymer water-soluble resin (b1) having a weight average molecular weight of 50,000 to 1,500,000, and a water-soluble resin of 1,000 to 30,000 Low-molecular weight-average molecular weight water-soluble resin (b2), the high-molecular water-soluble resin (b1) contains selected from the group consisting of polyethylene oxide, polypropylene oxide, polyvinylpyrrolidone, and cellulose derivatives At least one of the group, the low-molecular-weight water-soluble resin (b2) contains a monoether compound selected from polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyoxyethylene, and polyoxyethylene monomer At least one of the group consisting of stearate, polyoxyethylene sorbitan monostearate, polyethylene oxide-polypropylene oxide copolymer, and derivatives thereof. For example, the auxiliary board for drilling of item 1 or 2 of the scope of patent application, wherein the thickness of the layer containing the resin composition is 0.02 mm or more and 0.3 mm or less. For example, the auxiliary board for drilling in item 1 or 2 of the scope of patent application, wherein the thickness of the metal foil is 0.05mm or more and 0.5mm or less. A method of drilling drilling, by arranging the auxiliary board for drilling as in any one of the scope of patent application 1 to 10 on the top surface of the laminated board or multilayer board, and from the auxiliary board for drilling The top surface of the laminated board or multilayer board is drilled, and holes are formed in the laminated board or multilayer board.