RU2521908C1 - Stencil for hole drilling - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: stencil comprises a layer of crystallised water-soluble polymer composition from 0.02 to 0.3 mm thick which is applied onto at least one surface of backing up metal foil. Average size of the crystal grain of the water-soluble polymer composition amounts to 5-70 mcm, and standard grain size deviation does not exceed 25 mcm. Surface roughness Sm in the point of drill bit tip entering the water-soluble polymer composition layer amounts to maximum 8 mcm. The layer is formed by applying of hot melt of the water-soluble polymer composition directly onto the backing up metal foil or by applying of solution containing the water-soluble polymer composition with the following drying and further cooling under the temperature reducing from (120-160)°C to (25-40)°C during 60 sec at cooling rate of at least 1.5°C/sec.

EFFECT: prevention of polymer sticking to the drill bit tip and damage of the latter.

6 cl, 6 dwg, 5 tbl

Description

FIELD OF TECHNOLOGY

The invention relates to a stencil (a sheet with an arrangement of holes) for drilling holes, which is used when drilling holes in a multilayer (layered) material plated with copper, or in a multilayer printed circuit board.

BACKGROUND OF THE INVENTION

A common method for drilling holes in a copper-clad multilayer material or in a multilayer printed circuit board that is used to make printed circuit board components is a method in which a conventional carrier (rigid) metal foil, such as aluminum foil, or a sheet obtained by applying a layer of the polymer composition to the surface of the carrier metal foil (hereinafter, in the proposed description, this sheet is generally referred to as a "stencil for drilling holes"), placing They are used as a stencil and an accessory board on the upper surface of a copper-clad multilayer material, a multilayer printed circuit board or a bundle of a plurality of copper-clad multilayer materials or multilayer printed circuit boards, and then drilled holes.

Recently, the following requirements have been imposed on multilayer materials clad with copper and multilayer printed circuit boards used as components of printed circuit boards: providing a denser arrangement of components, increasing productivity and reducing costs, as well as improving the quality of drilling while improving location accuracy holes. Among examples of solving these problems, mention may be made of the drilling method proposed in Patent Document 1, JP H04-92494 A, comprising using a sheet of a water-soluble polymer such as polyethylene glycol. In addition, in Patent Document 2, JP H05-169400 A, a drill hole sheet was proposed including a lubricant obtained by applying a layer of a water-soluble polymer to a metal foil. Additionally, in Patent Document 3, JP 2003-136485 A, a drill hole stencil made by applying a layer of a water-soluble polymer to an aluminum foil was described, followed by the formation of a thin coating of a thermosetting polymer on this layer.

Nevertheless, since the development of techniques for reducing the size of printed circuit boards is slower than the rate of decrease in semiconductor sizes, a technological gap is created that tightens requirements for increasing the number of devices on printed circuit boards. To meet these requirements, it is necessary to achieve even higher accuracy of the location of the holes on the boards, as well as to create a stencil for drilling holes, characterized by even higher accuracy of the location of the holes.

In addition, due to increased competition as a result of globalization and the entry into the international market of new developing countries, the requirements for increased productivity and lower costs have become even more stringent than before. Thus, in order to further increase the accuracy of the location of the holes and increase the number of boards drilled at one time, it is necessary to create a stencil for drilling holes with even higher accuracy of the location of the holes.

SUMMARY OF THE INVENTION

The tasks solved by the invention

As indicated above, the requirements for multilayer materials clad with copper and multilayer printed circuit boards used as components of printed circuit boards include: increasing the number of devices placed on them, increasing productivity and reducing costs, and, in particular, improving location accuracy drilling holes, described in more detail below.

Firstly, an increase in the number of devices placed on printed circuit boards is expressed in a simple transition to minimum hole diameters. In mass production, the diameter of the drilled holes was reduced to 0.3 mm, 0.25 mm and 0.2 mm, and even to 0.15 mm and 0.105 mm. So, for drilling holes of extremely small diameters, for example, with minimum hole diameters of 0.08 mm, 0.075 mm, 0.06 mm and 0.05 mm, laser processing is used. The reason for this transition is that an extremely small diameter drill tip made of superhard metal is very brittle and breaks easily, and breaking a drill tip having an extremely small diameter is more likely to occur with traditional stencils for drilling holes. Using traditional techniques, it is not possible to prevent breakage of the drill tip and drill holes of extremely small diameters with high accuracy.

Secondly, the adhesion of the polymer to the tip of the drill reduces the accuracy of the location of the holes during drilling due to the displacement of the centering of the drill as a result of fluctuations in the center of gravity of the drill relative to the center line during its rotation. The sticking of even small amounts of polymer on the tip of the drill with an extremely small diameter is very likely to cause a shift in the center of the drill. In addition, if the adhered polymer is detached from the tip in the same place where the hole is drilled, the drill tip is in contact with the detached polymer, which causes a decrease in the centering accuracy of the drill tip and, as a result, a decrease in the accuracy of the hole location or breakage of the drill tip. Thus, despite the fact that when using drill tips with extremely small diameters, there should be a significant reduction in the amount of polymer wound on the drill tip, since the spiral groove for ejecting drilled material on the drill tip having an extremely small diameter is very narrow and shallow, the polymer easily wound on the tip of the drill, and this problem cannot be solved using traditional techniques. It should be noted that the aforementioned alignment means the ability to move exactly forward in the direction of the recess during drilling.

Thirdly, when the tip of the drill contacts a layer of the polymer composition deposited on the stencil, the cutting surface located on the tip is introduced into the layer of the polymer composition with sliding. When sliding, the degree of alignment decreases and, since the tip of the drill has an extremely small diameter due to an increase in the number of devices placed on the board, sliding must be limited to increase the accuracy of the location of the holes. Nevertheless, since the sliding of the drill tip with an extremely small diameter is additionally due to small irregularities on the surface of the polymer composition layer, with strong slipping, the drill tip can break. Using traditional techniques, it is impossible to reduce the degree of slip, which reduces the accuracy of the location of the holes.

Fourth, regardless of the diameter of the drill tip, market requirements include increased productivity and lower costs. Additionally, there is competition, exacerbated by globalization and the entry into the market of new developing countries, and the need for computerized technological design. In addition, the increase in drilling time due to an increase in the number of holes, which, in turn, is caused by an increase in the number of devices placed on the circuit boards, and the competition created by laser processing techniques, are factors that increase production productivity and reduce the cost of production. For example, along with globalization, the transfer of production to countries with a different price structure leads to higher competition, and in order to create a sales market for developing countries with extremely low average incomes, it is necessary to significantly reduce the cost of production. In particular, since market competition, which requires increasing production productivity and lowering the cost of production, is becoming tougher than before, there is a need to further increase the accuracy of the location of holes and increase the number of circuit boards, for example, of multilayer material clad with copper, or multilayer printed circuit boards in one pack drilled at a time, which can lead to increased productivity, reduced capital investment in drilling equipment, and reduced cost of production. However, using traditional methods, it is impossible to simultaneously reduce the cost of products, i.e. solve a problem that becomes more and more difficult every year, and increase the number of boards in a pack. In addition, an increase in the number of boards in a pack means the overlapping of so many sheets of copper-clad multilayer material or multilayer printed circuit boards that can still be processed using a drill tip with a known blade length while maintaining a high accuracy of the holes both above and above and at the bottom of a stack of sheets of copper-clad multilayer material or multilayer printed circuit boards.

The above problems can be solved by providing a drill hole stencil of the present invention to prevent breakage of the drill tip, providing high accuracy of hole placement and less polymer adhering to the drill tip compared to a conventional drill stencil.

Ways to solve problems

As a result of numerous studies aimed at solving the above problems, the inventors have revealed the particular importance of the influence of the surface condition at the point of penetration of the drill tip into the polymer composition layer, in particular the effect of the average crystalline grain size of the water-soluble polymer composition and the standard deviation of the grain size, as well as roughness Sm surface (average distance between bumps) at the point of insertion of the tip of the drill into the layer of the polymer composition. In addition, the authors found that the regulation of the cooling conditions during the manufacture of the stencil allows you to control the crystallization ability of the water-soluble polymer composition, as a result of which many high-density crystals having small sizes and a small standard deviation in size can be obtained, and the roughness is reduced Sm surface. The results obtained made it possible to increase the degree of alignment of the drill tip even when working with a drill tip of extremely small diameter, to increase the accuracy of the location of the holes during drilling, to reduce the amount of polymer wound on the drill tip, and to reduce the likelihood of breakage of the drill tip.

The invention is based on the results obtained, and its essence is as follows:

(1) A stencil for drilling holes, comprising a layer of crystallizable water-soluble polymer composition, the thickness of which is from 0.02 to 0.3 mm, formed on at least one surface of the carrier metal foil, in which the average crystal grain size of the water-soluble polymer composition is from 5 to 70 μm, and the standard deviation of the grain size is not more than 25 μm, the surface roughness Sm at the point of insertion of the drill tip into the layer of a water-soluble polymer composition is not more e 8 μm, and a layer of a water-soluble polymer composition is obtained by applying directly to the supporting metal foil a hot melt of the water-soluble polymer composition or by applying a solution containing a water-soluble polymer composition, followed by drying and subsequent cooling, including a temperature decrease from values from 120 ° C to 160 ° C, to values ranging from 25 ° C to 40 ° C, for 60 seconds at a cooling rate of at least 1.5 ° C / s.

(2) A stencil for drilling holes according to the above (1), in which the average crystal grain size of the water-soluble polymer composition is from 5 to 40 μm, and the standard deviation of the grain size is not more than 17 μm, and the surface roughness Sm of the layer of the water-soluble polymer composition at the point of entry of the tip of the drill is not more than 7 microns.

(3) A drill-hole stencil according to the above (1), wherein the water-soluble polymer composition comprises a water-soluble polymer (A) and further comprises at least one substance selected from a hydrophobic material (B1), a material (B2) having a temperature a melting point which exceeds the melting point of the water-soluble polymer (A) and a material (B3) that improves compatibility with the water-soluble polymer (A).

(4) A stencil for drilling holes according to the above (1), wherein the solution containing the water-soluble polymer composition further comprises water and a solvent whose boiling point is lower than the boiling point of water.

(5) A stencil for drilling holes according to the above (1), wherein the thickness of the carrier metal foil is from 0.05 to 0.5 mm.

(6) Stencil for drilling holes according to paragraph (1) above, used for processing multilayer materials clad with copper.

The beneficial effect of the invention

Since a drill hole stencil according to the invention can be obtained in which the water-soluble layer of the polymer composition comprises a plurality of closely spaced crystals with small crystal grains and a small standard deviation in size, and also has a reduced surface roughness Sm, the alignment of the drill tip can be improved, which provides drilling with high accuracy of the location of the holes and reducing the amount of polymer wound on the tip of the drill, which, in its turn, significantly reduces the frequency of breakage of the drill tip during drilling. Thus, the invention can provide high quality drilling and high productivity.

BRIEF DESCRIPTION OF GRAPHIC MATERIALS

Below the invention is described with reference to the accompanying graphic materials, in which:

figure 1 presents a series of enlarged photographs showing the surface condition of the layers of water-soluble polymer compositions in Examples and Comparative Examples;

Figure 2 is a schematic cross-sectional view showing drilling conditions using a conventional stencil for drilling holes;

3 is a schematic cross-sectional view showing drilling conditions using a stencil for drilling holes according to the invention;

figure 4 presents a graph showing the dependence of the accuracy of the location of the holes on the average size of crystalline grains in the layers of water-soluble polymer compositions obtained in the Examples and Comparative Examples;

figure 5 presents a graph showing the dependence of the accuracy of the location of the holes on the standard deviation of the sizes of crystalline grains in the layers of water-soluble polymer compositions obtained in the Examples and Comparative Examples; and

6 is a graph showing the dependence of the accuracy of the location of the holes on the roughness Sm of the surface layers of water-soluble polymer compositions obtained in the Examples and Comparative Examples.

DETAILED DESCRIPTION OF THE EMBODIMENTS OF THE INVENTION

The drilling template according to the invention is a drilling template comprising a layer of a water-soluble polymer composition capable of crystallizing (hereinafter referred to as a "layer of a water-soluble polymer composition") formed on at least one surface of a carrier metal foil.

In the stencil for drilling holes according to the invention, crystalline grains in a water-soluble polymer composition for which the grain size is in a certain range and the standard deviation is in a certain range are located on the surface of the stencil; this property, as well as the creation of a surface roughness Sm at the insertion point of the drill tip, the values of which are also in a certain range, can increase the accuracy of the location of the holes, reduce the amount of sticking polymer and prevent breakage of the drill tip during drilling.

To increase the accuracy of the location of the holes during drilling, the average crystal grain size of the water-soluble polymer composition should be from 5 to 70 microns, preferably should be from 5 to 50 microns, more preferably should be from 5 to 40 microns, more preferably should be from 5 to 30 microns , particularly preferably should be 5 to 20 microns, and most preferably should be 5 to 10 microns. It was experimentally found that if the average size of crystalline grains is less than 5 μm, then the surface of the water-soluble polymer composition becomes too smooth, which leads to slipping of the cutting surface of the drill tip, reducing the efficiency of the insertion of the drill into the surface of the stencil and deterioration of alignment, that is, with a significant reduction in size crystalline grains the accuracy of the location of the holes cannot be improved. On the other hand, it was experimentally established that if this value is more than 70 μm, then the irregularities created by crystalline grains affect the insertion of the drill tip into the surface of the stencil, which leads to poor centering and, consequently, to a decrease in the accuracy of the location of the holes.

Figure 2 schematically shows the drilling conditions using a conventional stencil for drilling holes, and Figure 3 schematically shows the drilling conditions using a stencil for drilling holes according to the invention. As shown in FIG. 3, in the presence of layer 2 of a water-soluble polymer composition according to the invention, in which the average crystal grain size 2a-2d of which layer 2 of the water-soluble polymer composition is optimized in accordance with the size of the tip of the drill 1, a high tip insertion efficiency is achieved 1 tip of the drill into layer 2 of a water-soluble polymer composition and it becomes possible to increase the accuracy of the location of the holes. On the other hand, as shown in FIG. 2, if there is a traditional layer 20 of the polymer composition in which the crystalline grains 20a-20c of which the layer 20 of the polymer composition are larger than the size of the tip 1 of the drill tip, the tip 1 of the drill tip may slip over the surfaces crystalline grains 20a-20c, which leads to a deterioration in alignment and a decrease in the accuracy of the location of the holes.

According to the invention, the size of the crystal grains (which may be referred to as the “crystal grain size”) of the water-soluble polymer composition according to the invention means the maximum diameter of the crystal grains located on the surface of the layer of the water-soluble polymer composition when viewing the screen from above in a direction perpendicular to the surface.

A method for measuring the average size of crystalline grains of a water-soluble polymer composition includes examining the surface of the layer of the polymer composition on a stencil for drilling holes using a V-Laser microscope with a 200-fold increase (model VK-9700, Keyence Corporation), measuring the maximum diameter of 50 randomly selected crystalline grains using the aforementioned microscope and calculating the average value (number average), which is taken as the average grain size of the water-soluble polymer composition. It should be noted that according to the invention, the calculation is carried out without considering grains with a crystalline grain size of less than 1 μm.

Additionally, in order to increase the accuracy of the location of the holes during drilling, in addition to optimizing the crystal grain sizes of the water-soluble polymer composition, it is necessary that the standard deviation of the average crystal grain size is not more than 25 μm, preferably not more than 20 μm, more preferably not more than 17 μm, more preferably not more 15 microns, particularly preferably not more than 10 microns, and most preferably not more than 5 microns. The reason for limiting the standard deviation values is that during the experiments the following was discovered: if the standard deviation exceeds 25 μm even with small average sizes of crystalline grains, large-diameter grains are scattered, forming large irregularities, which reduces the accuracy of the hole arrangement.

The method for calculating the standard deviation of the average crystal grain size of a water-soluble polymer composition includes examining the surface of the polymer composition layer on a stencil for drilling holes using a V-Laser microscope with a 200-fold increase (model VK-9700, Keyence Corporation), measuring the maximum diameter of 50 randomly selected crystalline grains using the mentioned microscope and the calculation of the average value. Then, the standard deviation of the measured maximum diameters of 50 crystalline grains is calculated.

In addition, the surface roughness of the layer of water-soluble polymer composition at the insertion point of the drill tip, in particular the average distance Sm between irregularities, which is defined in JIS B0601 (1994), should be no more than 8 μm, preferably not more than 7 μm, more preferably not more than 6 microns, more preferably not more than 5 microns and most preferably not more than 4 microns. The reason for this limitation is that during the experiments the following was discovered: if the surface roughness is more than 8 μm, the accuracy of the hole arrangement decreases and the alignment of the drill decreases, since the surface roughness affects the efficiency of the insertion of the drill tip into the surface of the stencil.

A method for determining the surface roughness Sm of a layer surface of a water-soluble polymer composition involves examining the surface of the layer of polymer composition using a 200-fold V-Laser microscope (Model VK-9700, Keyence Corporation), subtracting noise, and introducing gradient corrections (gradient surface corrections and automatic correction range of heights) and determining the surface roughness in the estimation range, the length of which is 500 μm in an arbitrary direction in the observed image (linear roughness agrees about JIS B0601 (1994)). Similar measurements are made for five points of one received image and the average value is calculated, which is taken as Sm.

A layer of a water-soluble polymer composition formed on a stencil for drilling holes according to the invention is obtained by applying directly to the carrier metal foil a hot melt of a water-soluble polymer composition and cooling, or by applying a solution containing a water-soluble polymer composition, by a coating method or the like, drying and cooling.

The water-soluble polymer composition included in the stencil for drilling holes according to the invention is a crystallizable composition comprising a water-soluble polymer (A). In particular, examples of the composition include a mixture of a water-soluble polymer (A), other materials, and the like. Other materials according to the invention include various inorganic compounds, organic compounds, mixtures, composite materials, complexes, low molecular weight substances, monomers, oligomers, high molecular weight substances, polymerization materials, natural polymers, fibers, mineral materials, hydrophobic materials, hydrophilic materials and the like.

The type of the water-soluble polymer (A) mentioned above is not particularly limited provided that it is a water-soluble polymer capable of crystallization, but preferably it is a water-soluble polymer having a high crystallization tendency, and preferably is one or more polymers selected from a group consisting of, for example, polyalkylene oxides, sodium polyacrylate, polyacrylamide, carboxymethyl cellulose, polytetramethylene glycol and polyesters polyalkylene glycol th.

Preferred examples of the polyalkylene oxides mentioned above are polyethylene oxide, polypropylene oxide and the like. More preferred is polyethylene oxide, which does not create steric barriers in the molecular structure. The polyalkylene glycol polyester is a condensation product obtained by the reaction of a polyalkylene glycol with a dibasic acid. Preferred examples of polyalkylene glycols include glycols such as, for example, polyethylene glycol, polypropylene glycol, polytetramethylene glycol and their copolymerization products and similar materials. Thus, the dibasic acid is preferably selected from partial esters of polycarboxylic acids, for example phthalic acid, isophthalic acid, terephthalic acid, sebacic acid and pyromellitic acid, acid anhydrides and the like. In addition, a condensation product containing polyethylene oxide as the main chain without creating steric hindrances in the molecular structure is more preferred.

Also, the water-soluble polymer composition according to the invention is preferably a composition comprising at least one material selected from a water-soluble polymer (A), a hydrophobic material (B1), a material (B2) whose melting point is higher than the melting temperature of the water-soluble polymer (A), and material (B3) that enhances compatibility between the water-soluble polymer (A) and the solvent.

When a hydrophobic material (B1) is added to the water-soluble polymer composition, the hydrophobic material (B1) is dispersed in the water-soluble polymer composition, and when the water-soluble polymer composition solidifies upon cooling, the particles of the hydrophobic material (B1), due to their hydrophobicity, serve as crystallization centers, causing the precipitation of many small crystalline grains of a water-soluble polymer composition.

Adding material (B2) to the water-soluble polymer composition, the melting temperature of which is higher than the melting temperature of the water-soluble polymer (A), allows you to create a difference in the curing rate during curing of the water-soluble polymer composition upon cooling. In particular, particles of material (B2) having a higher melting point, which solidifies in the early stages of curing, serve as crystallization centers, causing the deposition of many small crystalline grains of a water-soluble polymer composition. Among the materials (B2), the melting points of which are higher than the melting points of the water-soluble polymer (A), there are materials that not only cause the formation of fine crystalline grains with high efficiency, but also further reduce the surface roughness Sm of the layer surface of the water-soluble polymer composition.

The addition of a material (B3) to the water-soluble polymer composition that enhances compatibility between the water-soluble polymer (A) and the solvent contributes to the formation of fine crystalline grains during curing of the water-soluble polymer composition by drying and cooling, since the hydroxy groups contained in the molecular structure (B3) contribute to uniform dispersion water-soluble polymer (A) in a solvent. Among the materials (B3) that increase the compatibility between the water-soluble polymer (A) and the solvent, there are materials that not only cause the formation of fine crystalline grains with high efficiency, but also further reduce the surface roughness Sm of the layer surface of the water-soluble polymer composition.

In addition, any of these hydrophobic materials (B1), materials (B2), the melting point of which is higher than the melting temperature of the water-soluble polymer (A), and materials (B3) that increase the compatibility between the water-soluble polymer (A) and the solvent, can be the only the material or may be a mixture of two or more materials. Additionally, any of the hydrophobic materials (B1), materials (B2), the melting temperature of which is higher than the melting temperature of the water-soluble polymer (A), and materials (B3) that increase the compatibility between the water-soluble polymer (A) and the solvent, can be used in combination.

Additionally, the total amount of hydrophobic material (B1), material (B2) in the mixture, the melting point of which is higher than the melting temperature of the water-soluble polymer (A), and material (B3), which increases the compatibility between the water-soluble polymer (A) and the solvent, in terms of 100 mass. parts of water-soluble polymer (A) should be from 0.1 mass. parts to 5 mass. parts, preferably from 0.1 mass. parts to 3 mass. parts, more preferably from 0.2 mass. parts to 3 mass. parts and particularly preferably from 0.2 mass. parts to 2 mass. parts. If this amount is less than 0.1 mass. parts, the density of the crystals may be low, and if this amount is more than 5 mass. parts, it is economically disadvantageous. It is wise to choose materials (B1, B2, B3) that even in small quantities can achieve the desired effect.

According to the invention, the choice of hydrophobic material (B1) is not particularly limited, provided that it has hydrophobic properties. As examples of hydrophobic polymers, long chain alcohols, hydrophobic polysaccharides, inorganic compounds and the like can be used. In particular, examples of thermoplastic polymers can include powders or particles, including urethane, silicon, acrylic based, and polyetherimides, polyimides, polyvinyl chloride, vinyl acetate, polyamides, polypropylene, polyvinyl acetate, polybutene, polymethacrylamide, powdered cellulose cellulose derivatives, polyvinyl ether, phenoxy-containing polymers, a copolymer of ethylene and vinyl alcohol, polytetrafluoroethylene and the like; examples of thermosetting polymers may include powders or particles including epoxy polymers, silicon-containing polymers, phenolic polymers, urea polymers, acrylic polymers, polyethylene glycol dimethacrylate polymer, a polymer including bismaleimide, a polymer including bismaleimidtriazine, a polymer including cyanate, a polymer, a cyanate, and similar substances; examples of long chain alcohols may include lauryl alcohol, cetyl alcohol, stearyl alcohol, oleyl alcohol, linolyl alcohol and the like; examples of inorganic compounds may include materials including talc, molybdenum disulfide, zinc molybdate, graphite, tungsten disulfide, fluorinated graphite, boron nitride and the like; in addition, accordingly, one or two or more substances in the mixture can be used. Also, as a more preferred hydrophobic material (B1), enhancing the effect according to the invention, stearyl alcohol, zinc molybdenum, graphite, boron nitride and the like are used. They are preferred because they have a high dispersion ability in a solution of a water-soluble polymer composition.

The choice of material (B2), the melting temperature of which is higher than the melting temperature of the water-soluble polymer (A), is also not particularly limited, provided that its melting temperature is higher than the melting temperature of the water-soluble polymer (A). For example, amino acids, organic acids, salts of organic acids, organic salts, organic phosphates, polysaccharides, rosins, inorganic compounds and the like can be used for this purpose. In particular, amino acids include monosodium glutamate and the like; organic acids include malic acid, malonic acid, succinic acid, fumaric acid, maleic acid, cyanuric acid and the like; organic acid salts include metal and organic acid salts, for example malic acid, malonic acid, succinic acid, fumaric acid, maleic acid, formic acid, acetic acid, propionic acid, stearic acid, cyanuric acid and the like; organic salts include melamine cyanurate and the like; organic phosphates include sodium adenosine triphosphate salt and the like; polysaccharides include cellulose, chitin, starch, glycogen, agarose, pectin and the like; rosins include tall oil rosin, tall oil fatty acid rosin and the like; and inorganic compounds include sodium chloride, sodium sulfate, magnesium sulfate and the like. In particular, more preferred materials (B2), the melting point of which is higher than the melting temperature of the water-soluble polymer (A), enhancing the effect according to the invention include sodium glutamate, succinic acid, sodium formate, calcium formate, sodium stearate, calcium stearate, cellulose and the like substances.

Examples of material (B3) that improves compatibility between the water-soluble polymer (A) and the solvent include polyalcohols, sugar alcohols, amino acid derivatives of alcohols and the like containing a hydroxy group in the molecular structure. Polymers such as polyethylene glycol included in the water-soluble polymer (A) should be excluded from the group of polyalcohols; however, in addition to polymers, polyalcohols include trimethylolpropane, pentaerythritol, neopentyl glycol, trimethylol ethane and the like; sugar alcohols include sorbitol, xylitol, inositol and the like; and amino acid derivatives of alcohols include hydroxyaniline, oxytoluidine, tyrosine, aminodeoxy and the like. In particular, more preferred materials (B3) that increase the compatibility between the water-soluble polymer (A) and the solvent, which enhance the effect of the invention, include pentaerythritol, sorbitol, xylitol, inositol and the like.

The thickness of the layer of the water-soluble polymer composition may vary depending on the diameter of the drill tip used for drilling, the structure of the processed multilayer material clad with copper, or a multilayer printed circuit board and similar factors, but usually this thickness is from 0.02 to 0.3 mm and preferably between 0.02 and 0.2 mm. If the thickness of the layer of water-soluble polymer composition is less than 0.02 mm, then it does not provide sufficient lubricating action, that is, the load on the drill tip increases, which can lead to breakage of the drill tip. On the other hand, if the layer thickness of the water-soluble polymer composition is more than 0.3 mm, this can increase the amount of polymer wound on the tip of the drill.

In particular, when applying the solution containing the water-soluble polymer composition directly to the supporting metal foil by a coating method or the like, the solution used is preferably a solution containing water and a solvent, the boiling point of which is lower (more preferably lower than at least 15 ° C) the boiling point of water. The choice of a solvent whose boiling point is lower than the boiling point of water is not particularly limited, and for this purpose, for example, ethanol and alcohols such as methanol and isopropyl alcohol, and low boiling solvents, for example methyl ethyl ketone and acetone, can be used.

The presence of a solvent whose boiling point is lower than the boiling point of water helps to reduce the size of crystalline grains and to reduce the surface roughness Sm, which increases the accuracy of the location of the holes. Each of the solvents has a distinctive property: ethanol contributes to a decrease in crystalline grain size, and methyl ethyl ketone contributes to a decrease in the surface roughness Sm. The use of ethanol with high efficiency increases the accuracy of the hole arrangement. More preferred low boiling solvents are ethanol and acetone. In general, increasing the added amount of a low boiling solvent helps to reduce the size of the crystalline grain, reduce the surface roughness Sm, and reduce the standard deviation of the size of the crystal grains. However, as the added amount of the low boiling solvent increases, the effect of increasing the accuracy of the hole arrangement is gradually saturated. In addition, if the difference in boiling points of the low boiling solvent and water is less than 15 ° C, the desired effect is hardly achieved.

The ratio of added water to solvent, the temperature of which boiling below the boiling point of water should be in the range of 90/10 to 50/50, preferably should be in the range of 80/20 to 50/50, and most preferably should be in the range of 70 / 30 to 50/50. If the ratio of the added water to the solvent, the boiling point of which is lower than the boiling point of water, is less than 10, then the crystallization density can be reduced. If the ratio of added water to solvent, the boiling point of which is lower than the boiling point of water, is more than 50, then this is economically disadvantageous and can lead to production disruptions carried out on an industrial scale.

If in the manufacture of a stencil, a method of applying a hot melt of a water-soluble polymer composition directly to a supporting metal foil and subsequent cooling is used, then the choice of a method for producing a stencil has no particular restrictions.

Conventional kneading agents may be used to knead the water-soluble polymer composition; for this purpose, for example, a biaxial roller mill, a mixer, a two-blade kneading machine, a plunger extruder and the like are preferably used. In addition, to prevent decomposition of the water-soluble polymer composition when it is kneaded, the water-soluble polymer composition is preferably kneaded in a nitrogen atmosphere. Additionally, to uniformly disperse the water-soluble polymer composition, the composition is preferably kneaded at a temperature of from 120 ° C to 160 ° C. If the kneading temperature is less than 120 ° C, then the water-soluble polymer composition becomes heterogeneous, which can adversely affect such product properties as, for example, the appearance and accuracy of the hole arrangement, and if the kneading temperature is more than 160 ° C, then decomposition water-soluble polymer composition, which can adversely affect the properties of the product, for example, the accuracy of the location of the holes.

The choice of the method of applying a coating of a water-soluble polymer composition directly to a supporting metal foil also has no particular limitations.

For this purpose, a conventional coating apparatus may be used; Preferred examples of the plants used include a scraper device for coating, an extrusion device for coating, a spinneret device for coating, an irrigation device and the like. If upon application a layer of a water-soluble polymer composition of uneven thickness is obtained, this can adversely affect the properties of the product, for example, the accuracy of the location of the holes, therefore the above-mentioned device is preferably used for uniformly coating a hot melt of a water-soluble polymer composition.

If for applying a solution containing a water-soluble polymer composition directly onto a supporting metal foil, the above-described coating method or a similar method is used followed by drying and cooling, the choice of the method of coating the stencil is not particularly limited, and the traditional method can be applied for this purpose installation for coating. For example, for coating in the form of a layer of a water-soluble polymer composition of uniform thickness, conventional coating agents are preferably used, for example a coating device with a grooved roller, a roller coating device, a scraper coating device, an extrusion coating device, a spinneret coating device coatings, irrigation coating apparatus and similar devices. The uneven layer thickness of the water-soluble polymer composition can adversely affect the properties of the product, for example, the accuracy of the location of the holes, therefore, the above method is preferably used to uniformly apply a solution of the water-soluble polymer composition.

In addition, it is necessary to optimize the conditions for coating from a solution of a water-soluble polymer composition directly on a supporting metal foil and subsequent drying of the solution of a water-soluble polymer composition depending on the thickness of the layer of the water-soluble polymer composition and the amount of water.

In particular, to perform drying, it is necessary to maintain a temperature of 120 ° C to 160 ° C for a time of 10 seconds to 600 seconds, it is preferable to maintain a temperature of 120 ° C to 160 ° C for a time, of 10 seconds to 500 seconds, it is more preferable to maintain a temperature of 120 ° C to 160 ° C for a time of 15 seconds to 40 seconds, and it is most preferable to maintain a temperature of 120 ° C to 150 ° C for a period of 20 seconds or more about 300 seconds. If the drying temperature is less than 120 ° C, or if the exposure time at the drying temperature is less than 10 seconds, then there is a possibility that the solvent will remain inside the layer of the water-soluble polymer composition or the amount of heat required to melt the water-soluble polymer composition will not be reached, which will result to irregularities in the layer of a water-soluble polymer composition. On the other hand, if the drying temperature is high and exceeds 200 ° C, or if the exposure time is more than 600 seconds, then the water-soluble polymer composition decomposes, which leads to a deterioration in the appearance of the product.

Additionally, after coating from a solution of a water-soluble polymer composition onto a carrier metal foil and drying, the concentration of solvent remaining in the layer of the water-soluble polymer composition after drying is preferably less than 5%.

In addition, in order to obtain a high density of crystals in the layer of the polymer composition, along with conventional drying, ultrasonic vibrations and drying under reduced pressure can be applied.

It should be noted that the cooling of a water-soluble polymer composition using a traditional technique in which the cooling rate is less than 1.2 ° C / s can result in large crystalline grains, high standard deviations and surface roughness Sm, which may impair the accuracy of the arrangement holes, increase the amount of sticking polymer and create similar problems. Thus, the cooling conditions according to the invention include the need for cooling from an initial cooling temperature of 120 ° C to 160 ° C to a final cooling temperature of 25 ° C to 40 ° C for 60 seconds at a cooling rate of component not less than 1,5 ° C / sec.

If the final temperature to which cooling is performed is more than 40 ° C, then a reduction in diameter and obtaining uniform crystalline grains, which are the hallmarks of the invention, cannot be realized. Similarly, if the cooling time is more than 60 seconds, then reducing the diameter and obtaining homogeneous crystalline grains, which are the hallmarks of the object of the invention, also cannot be realized. On the other hand, if the temperature to which the cooling is performed has a low value, but is more than 15 ° C, then the stencil warps, and, in addition, dew condensation may occur after processing, which is undesirable.

If the cooling rate is less than 1.5 ° C / s, then the cooling time is extended to a period of more than 60 seconds, which is undesirable.

To obtain a more pronounced effect of reducing the diameter and uniformity of the crystal grains, cooling is preferably carried out from a temperature of 120 ° C to 160 ° C to a temperature of 25 ° C to 40 ° C for 50 seconds at a cooling rate of at least 2 ° C / s, preferably from a temperature of 120 ° C to 160 ° C, to a temperature of 25 ° C to 40 ° C for 40 seconds, with a cooling rate of at least 2.5 ° C / s, more preferably from a temperature of 120 ° C to 160 ° C, to temperatures of 25 ° C to 40 ° C for 30 seconds, with a cooling rate of at least 3 ° C / s, particularly preferably from a temperature of 120 ° C to 160 ° C to a temperature of 25 ° C to 40 ° C, for 20 seconds, at a cooling rate of at least 4.5 ° C / sec, and most preferably from a temperature of 120 ° C to 160 ° C to a temperature of 25 ° C to 40 ° C, for 15 seconds, at a cooling rate of at least 6 ° C / s.

The choice of a carrier metal foil to be included in the stencil for drilling holes according to the invention is not particularly limited provided that it is made of a metal material with high adhesion to a water-soluble polymer composition and can withstand the impact of the drill tip. As the metal from which the supporting metal foil is obtained, aluminum can, for example, be used; the thickness of the carrier metal foil is usually from 0.05 to 0.5 mm, preferably 0.05 to 0.3 mm. If the thickness of the aluminum foil is less than 0.05 mm, then during the drilling, burrs quickly form on the multilayer material, and if the thickness of the foil is more than 0.5 mm, it is difficult to eject the chips generated during drilling. The material of the aluminum foil is preferably aluminum, the purity of which is not less than 95%, in particular materials of the grades 5052, 3004, 3003, 1N30, 1N99, 1050, 1070, 1085, 1100, 8021 and similar materials mentioned in JIS H4100 are used , JIS H4160 and JIS H4170. Obtaining a carrier metal foil from high-purity aluminum foil, along with the lubricating effect of a water-soluble polymer composition, can reduce the impact of the tip of the drill bit, increase the efficiency of the input tip of the drill tip and the accuracy of the holes.

In addition, to increase adhesion to the water-soluble polymer composition, it is preferable to use aluminum foil on the surface of which a polymer membrane with a thickness of from 0.001 to 0.02 mm is preliminarily applied, and more preferably the thickness of the polymer membrane is from 0.001 to 0.15 mm, and particularly preferably the thickness a polymer membrane ranges from 0.001 to 0.1 mm. The choice of the polymer from which the polymer membrane is obtained is not particularly limited provided that it improves the adhesion strength to the water-soluble polymer composition, and thermoplastic polymers or thermosetting polymers can be used for this purpose. For example, thermoplastic polymers include urethane based polymers, vinyl acetate based polymers, vinyl chloride based polymers, polyester based polymers and their copolymers. Thermosetting polymers include, for example, epoxide-based polymers and cyanate-based polymers. Additionally, according to the invention, a commercially available metal foil with a polymer coating previously applied to it using a known method can also be used as a carrier metal foil.

A drilling stencil according to the invention is used for drilling holes in printed circuit materials, for example, copper plated multilayer materials or multilayer printed circuit boards. In particular, the stencil is placed on top of one or a plurality of layers of copper-clad multilayer material, or one or a plurality of multilayer printed circuit boards arranged in such a way that the carrier metal foil is facing the printed circuit material, and drilling is performed from the side of the layer surface of a water-soluble polymer composition applied on a stencil for drilling holes.

DESCRIPTION OF EMBODIMENTS OF THE INVENTION

Below the invention is described in more detail using Examples and Comparative Examples. It should be noted that the Examples are only one of non-limiting embodiments of the present invention. It should also be noted that in the Examples, "polyethylene glycol" may be indicated by the abbreviation "PEG" (eng. Polyethylene glycol), and "polyethylene oxide" by the abbreviation "PEO" (eng. Polyethylene oxide).

Table 1 presents the technical characteristics of polymers, solvents, additives and a supporting metal foil, as well as the cooling conditions that were used to obtain stencils for drilling in the Examples and Comparative Examples, as well as the characteristics of the diameters of the drill tips that were used for drilling.

Table 1 Classification Name and condition Trade name Manufacturer Notes Polymer type (a) Polyethylene oxide ALTOP MG150 Meisei Chemical Works, Ltd. Mn = 150,000 (b) Polyethylene oxide ALKOX L11 Meisei Chemical Works, Ltd. Mn = 110000 (c) Polyethylene glycol PEG20000 Sanyo Chemical Industries, Ltd. Mn = 20,000 (d) Polyethylene glycol PEG4000 Sanyo Chemical Industries, Ltd. Mn = 4000 (e) Polycondensation product of polyethylene glycol and dimethyl terephthalate PAOGEN PP-15 Dai-ichi Kogyo Seiyaku, Co., Ltd. Mn = 100000 Solvent (f) Water Ion Exchange Purified Water B.p. = 100 ° C (g) Meoh Wako Pure Chemical Industries, Ltd. T. boiling point = 64.7 ° C, 99.9% pure (h) MEK Wako Pure Chemical Industries, Ltd. B.p. = 79.5 ° C, 99.9% pure (i) IPA Wako Pure Chemical Industries, Ltd. T. boil. = 83 ° C, purity 99.9% (j) EtOH Wako Pure Chemical Industries, Ltd. T. boil = 78.4 ° C, purity 99.9% (k) Acetone Wako Pure Chemical Industries, Ltd. T. boiling point = 56.1 ° C, purity 99.9%

Additive (B1) Hydrophobic Material (l) Acrylic-based thermoplastic polymer BYK-011 BYK Chemie Japan - (m) Silicon-based thermoplastic polymer BYK-349 BYK Chemie Japan - (B2) High melting point material (n) Sodium formate Mitsubishi Gas Chemical Company, Inc. - (o) Sodium chloride Wako Pure Chemical Industries, Ltd. - (B3) Compatibility Enhancing Material (p) Pentaerythritol Wako Pure Chemical Industries, Ltd. Carrier Metal Foil (t) 70µ aluminum Mitsubishi Aluminum Co., Ltd. Specialist. JIS, aluminum alloy number 1100 (u) Aluminum 100µ Mitsubishi Aluminum Co., Ltd. Specialist. JIS, aluminum alloy number 1100 Cooling rate (q) Quick cooling at 3.1 ° C / s (Drying at 120 ° C for 3 minutes → Cooling to 25 ° C in 30 seconds) (r) Quick cooling at 2.2 ° C / s (Drying at 160 ° C for 3 minutes → Cooling to 30 ° C in 60 seconds) (s) Slow cooling at 1.1 ° C / s (Drying at 120 ° C for 3 minutes → Cooling to 25 ° C in 90 seconds) Drill Tip Diameter (v) 0.08 mm ϕ KMV J948 0.08 × 1.2 Union Tool Co. (w) 0.105 mm ϕ KMCL518A 0.105 × 1.8 Union Tool Co. (x) 0.15 mm ϕ NEU L004 0.15 × 2.5 Union Tool Co.

IPA - isopropyl alcohol (isopropyi alcohol)

MEK - methyl ethyl ketone

Example 1

80 mass. parts of polyethylene oxide, the number average molecular weight of which was 150,000 (ALTOP MG-150, supplied by Meisei Chemical Works, Ltd.), and 20 mass. parts of polyethylene glycol, the number average molecular weight of which was 20,000 (PEG20000 supplied by Sanyo Chemical Industries, Ltd.) was dissolved in water so that the solid polymer content was 30%. Then added 0.5 mass. parts of sodium formate (supplied by Mitsubishi Gas Chemical Company, Inc.), calculated on the solids content of the water-soluble polymer mixture, and brought to complete dissolution. An aluminum foil, on one surface of which was coated with an epoxy polymer membrane with a thickness of 0.01 mm (used aluminum foil: 1100 (thickness 0.07 mm), supplied by Mitsubishi Aluminum Co, Ltd.) was applied with a barcode device a solution of the obtained water-soluble polymer composition so that the layer thickness of the water-soluble polymer composition after drying was 0.03 mm, dried using a drying device at 120 ° C for 3 minutes and further cooled at a cooling rate of 3.1 ° C / sec, receiving a stencil for drilling holes (see Table 2).

The resulting drill hole stencil was placed on top of a stack of six stacked sheets of copper plated laminate, each 0.1 mm thick (CCL-HL832HS, copper foil, both 5 micron surfaces, supplied by Mitsubishi Gas Chemical Company, Inc .) so that the layer of the water-soluble polymer composition is the uppermost layer; a stack of sheets of copper-clad multilayer material stacked on top of each other was placed on an auxiliary board (bakelite plate) and 20 drills were performed, including 3000 holes for one drill tip, with the following parameters: drill tip diameter 0.105 mm (KMS L518A 0.105 × 1.8 , supplied by Union Tool Co.), a rotation speed of 330,000 rpm, and a feed speed of 8 μm / revolution (see Table 2).

The average size (μm) of crystalline grains of water-soluble polymer compositions, the standard deviation (μm) of the size of crystalline grains and the surface roughness Sm (μm) of the stencils are shown in Table 3.

Examples 2 to 20 and Comparative Examples 1 to 36

Water-soluble polymer compositions, the parameters of which are presented in Table 1 and Table 2, used in Examples 2-20 and Comparative Examples 1-36, were obtained in accordance with the words of Example 1, deposited on sheets of aluminum foil, dried and cooled, resulting in received stencils for drilling, with which they performed drilling.

So, in Example 2, 80 mass. parts of polyethylene oxide, the number average molecular weight of which was 150,000 (ALTOP MG-150, supplied by Meisei Chemical Works, Ltd.), and 20 mass. parts of polyethylene glycol, the number average molecular weight of which was 20,000 (PEG20000 supplied by Sanyo Chemical Industries, Ltd.) was dissolved in a mixture of water and MeOH (methanol) to obtain a solid polymer content of 30%. The water / MeOH ratio was 90 mass. parts / 10 mass. parts. This example shows the use of a low boiling solvent whose boiling point is lower than the boiling point of water.

In contrast, Comparative Example 26 used the commercially available "LX120" supplied by Sang-A Flontec Co., Ltd, in Comparative Example 27 used the commercially available "AL-100040" supplied by Yong Li Chuan Industrial Co., Ltd, and in Comparative Example 29 used the commercially available "LAE-1007" supplied by Uniplus Electonics Co., Ltd.

The average size (μm) of the crystal grains of water-soluble polymer compositions, the standard deviation (μm) of the crystal grain sizes and the surface roughness Sm (μm) of the stencils are shown in Table 3. Additionally, Figure 1 shows enlarged images of the state of the surface layers of some examples of water-soluble polymer compositions (Examples 2, 3, 10, 12 and 19 and Comparative Examples 2, 10, 20, 26 and 28).

Table 2-1 No. E1 E2 E3 E4 E5 E6 E7 E8 Polymer type (a) ALTOP MG150 80 80 80 0 80 80 0 80 (b) ALKOX L11 0 0 0 0 0 0 0 0 (c) PEG20000 twenty twenty twenty twenty twenty twenty twenty twenty (d) PEG4000 0 0 0 60 0 0 60 0 (e) PAOGEN PP-15 0 0 0 twenty 0 0 twenty 0 Solvent (f) Water one hundred 90 90 70 90 90 70 90 (g) MeOH b.p. = 64.7 ° C 0 10 10 0 10 10 0 10 (h) MEK bp = 79.5 ° C 0 0 0 0 0 0 0 0 (i) IPA bp = 83 ° C 0 0 0 thirty 0 0 thirty 0 (j) EtOH b.p. = 78.4 ° C 0 0 0 0 0 0 0 0 (k) Acetone b.p. = 56.1 ° C 0 0 0 0 0 0 0 0 Additive (B1) (l) BYK-011 0,0 0,0 0,0 0,0 0,0 0,0 0,0 0,0 (m) BYK-349 0,0 0,0 0,0 0,0 0,0 0,0 0,0 0,0 (B2) (n) Sodium formate 0.5 0.5 0.4 0.3 0.4 0.4 0.3 0.4 (o) Sodium chloride 0,0 0,0 0,0 0,0 0.5 0.5 0,0 0.5 (B3) (p) Pentaerythritol 0,0 0,0 0,0 2.0 0,0 0,0 2.0 0,0 Cooling rate (q) Quick cooling at 3.1 ° C / s ○ ○ ○ ○ ○ ○ (r) Fast cooling at 2.2 ° C / s ○ ○ (s) Slow cooling at 1.1 ° C / s Carrier Metal Foil (t) 70 μm aluminum ○ ○ ○ ○ (u) 100 μm aluminum ○ ○ ○ ○ Drill Tip Diameter (v) 0.08 mm ϕ (w) 0.105 mm ϕ ○ ○ ○ ○ (x) 0.15 mm ϕ ○ ○ ○ ○

No. E9 E10 E11 E12 E13 E14 E15 E16 Polymer type (a) ALTOP MG150 0 80 80 80 80 0 80 80 (b) ALKOX L11 80 0 0 0 0 twenty 0 0 (c) PEG20000 twenty twenty twenty twenty twenty 80 twenty twenty (d) PEG4000 0 0 0 0 0 0 0 0 (e) PAOGEN PP-15 0 0 0 0 0 0 0 0 Solvent (f) Water 90 90 90 one hundred 90 60 90 90 (g) MeOH b.p. = 64.7 ° C 10 10 10 0 10 40 10 10 (h) MEK bp = 79.5 ° C 0 0 0 0 0 0 0 0 (i) IPA bp = 83 ° C 0 0 0 0 0 0 0 0 (j) EtOH b.p. = 78.4 ° C 0 0 0 0 0 0 0 0 (k) Acetone b.p. = 56.1 ° C 0 0 0 0 0 0 0 0 Additive (B1) (l) BYK-011 0,0 0,0 0,0 0,0 0,0 0,0 0,0 0,0 (m) BYK-349 0,0 0,0 0,0 0,0 0,0 0,0 0,0 0,0 (B2) (n) Sodium formate 0.1 0.3 0,0 0.3 0.3 0.3 0.1 0.4 (o) Sodium chloride 0,0 0,0 0.5 0,0 0,0 0,0 0,0 0,0 (B3) (p) Pentaerythritol 0,0 0,0 0,0 0,0 0,0 0,0 0,0 0,0 Cooling rate (q) Quick cooling at 3.1 ° C / s ○ ○ ○ ○ ○ ○ (r) Fast cooling at 2.2 ° C / s ○ (s) Slow cooling at 1.1 ° C / s Carrier Metal Foil (t) 70 μm aluminum ○ ○ (u) 100 μm aluminum ○ ○ ○ ○ ○ ○ Drill Tip Diameter (v) 0.08 mm ϕ (w) 0.105 mm ϕ ○ ○ (x) 0.15 mm ϕ ○ ○ ○ ○ ○ ○

Table 2-2 No. E17 E18 E19 E20 C1 C2 C3 C4 Polymer type (but) ALTOP MG150 0 80 0 80 80 80 0 80 (b) ALKOXL11 80 0 twenty 0 0 0 80 0 (from) PEG20000 twenty twenty 80 twenty twenty twenty twenty twenty (d) PEG4000 0 0 0 0 0 0 0 0 (e) PAOGEN PP-15 0 0 0 0 0 0 0 0 Solvent (f) Water 90 90 60 90 80 60 90 80 (g) MeOH b.p. = 64.7 ° C 10 10 40 10 0 40 10 0 (h) MEK bp = 79.5 ° C 0 0 0 0 twenty 0 0 0 (i) IPA bp = 83 ° C 0 0 0 0 0 0 0 0 (j) EtOH b.p. = 78.4 ° C 0 0 0 0 0 0 0 0 (k) Acetone b.p. = 56.1 ° C 0 0 0 0 0 0 0 twenty Additive (B1) (l) BYK-011 0.1 0,0 0,0 0,0 0,0 0,0 0,0 0,0 (m) BYK-349 0,0 0,0 0,0 0,0 0,0 0,0 0,0 0,0 (B2) (n) Sodium formate 0,0 0,0 0.3 0.4 0,0 0,0 0.1 0,0 (o) Sodium chloride 0,0 0.1 0,0 0.5 0,0 0,0 0,0 0,0 (B3) (p) Pentaerythritol 0,0 0,0 0,0 0,0 0,0 0,0 0,0 0,0 Cooling rate (q) Quick cooling at 3.1 ° C / s ○ ○ ○ ○ ○ ○ ○ (r) Fast cooling at 2.2 ° C / s ○ (s) Slow cooling at 1.1 ° C / s Carrier Metal Foil (t) 70 μm aluminum ○ ○ ○ (u) 100 μm aluminum ○ ○ ○ ○ ○ Drill Tip Diameter (v) 0.08 mm ϕ ○ (w) 0.105 mm ϕ ○ ○ (x) 0.15 mm ϕ ○ ○ ○ ○ ○

No. C5 C6 C7 C8 C9 C10 C11 C12 Polymer type (but) ALTOP MG150 80 0 0 80 80 0 80 80 (b) ALKOX L11 0 80 80 0 0 80 0 0 (from) PEG20000 twenty twenty twenty twenty twenty twenty twenty twenty (d) PEG4000 0 0 0 0 0 0 0 0 (e) PAOGEN PP-15 0 0 0 0 0 0 0 0 Solvent (f) Water 80 80 90 one hundred 80 90 90 80 (g) MeOH b.p. = 64.7 ° C 0 twenty 10 0 0 10 10 twenty (h) MEK bp = 79.5 ° C 0 0 0 0 0 0 0 0 (i) IPA bp = 83 ° C 0 0 0 0 twenty 0 0 0 (j) EtOH b.p. = 78.4 ° C twenty 0 0 0 0 0 0 0 (k) Acetone b.p. = 56.1 ° C 0 0 0 0 0 0 0 0 Additive (B1) (l) BYK-011 0,0 0,0 0.1 0,0 0,0 0,0 0.1 0,0 (m) BYK-349 0,0 0,0 0,0 0,0 0,0 0,0 0,0 0,0 (B2) (n) Sodium formate 0,0 0,0 0,0 0.1 0,0 0,0 0,0 0,0 (o) Sodium chloride 0,0 0,0 0,0 0,0 0,0 0,0 0,0 0,0 (B3) (p) Pentaerythritol 0,0 0,0 0,0 0,0 0,0 0,0 0,0 0,0 Cooling rate (q) Quick cooling at 3.1 ° C / s ○ ○ ○ ○ ○ ○ ○ ○ (r) Fast cooling at 2.2 ° C / s (s) Slow cooling at 1.1 ° C / s Carrier Metal Foil (t) 70 μm aluminum (u) 100 μm aluminum ○ ○ ○ ○ ○ ○ ○ ○ Drill Tip Diameter (v) 0.08 mm ϕ (w) 0.105 mm ϕ (x) 0.15 mm ϕ ○ ○ ○ ○ ○ ○ ○ ○

Table 2-3 No. C13 C14 C15 C16 C17 C18 C19 C20 Polymer type (but) ALTOP MG150 80 80 80 80 80 80 80 80 (b) ALKOX L11 0 0 0 0 0 0 0 0 (from) PEG20000 twenty twenty twenty twenty twenty twenty twenty twenty (d) PEG4000 0 0 0 0 0 0 0 0 (e) PAOGEN PP-15 0 0 0 0 0 0 0 0 Solvent (f) Water 90 90 90 90 90 90 60 80 (g) MeOH b.p. = 64.7 ° C 10 10 10 10 10 10 0 0 (h) MEK bp = 79.5 ° C 0 0 0 0 0 0 0 0 (i) IPA bp = 83 ° C 0 0 0 0 0 0 0 0 (j) EtOH b.p. = 78.4 ° C 0 0 0 0 0 0 40 twenty (k) Acetone b.p. = 56.1 ° C 0 0 0 0 0 0 0 0 Additive (B1) (l) BYK-011 0.3 0.1 0,0 0,0 0.3 0,0 0,0 0,0 (m) BYK-349 0,0 0,0 0,0 0.1 0,0 0,0 0,0 0,0 (B2) (n) Sodium formate 0,0 0,0 0,0 0,0 0,0 0,0 0,0 0,0 (o) Sodium chloride 0,0 0,0 0.5 0,0 0,0 0.5 0,0 0,0 (B3) (p) Pentaerythritol 0,0 0,0 0,0 0,0 0,0 0,0 0,0 0,0 Cooling rate (q) Rapid cooling at 3.1 ° C / s ○ ○ ○ ○ ○ ○ ○ ○ (r) Fast cooling at 2.2 ° C / s (s) Slow cooling at 1.1 ° C / s Carrier Metal Foil (t) 70 μm aluminum ○ ○ ○ ○ (u) 100 μm aluminum ○ ○ ○ ○ Drill Tip Diameter (v) 0.08 mm ϕ (w) 0.105 mm ϕ ○ ○ ○ ○ (x) 0.15 mm ϕ ○ ○ ○ ○

No. C21 C22 C23 C24 C25 C26 C27 C28 Polymer type (but) ALTOPMG150 80 80 80 80 80 - - one hundred (b) ALKOX L11 0 0 0 0 0 - - 0 (from) PEG20000 twenty twenty twenty twenty twenty - - 0 (d) PEG4000 0 0 0 0 0 - - 0 (e) PAOGENPP-15 0 0 0 0 0 - - 0 Solvent (f) Water 90 90 90 60 80 - - one hundred (g) MeOH b.p. = 64.7 ° C 10 10 10 0 0 - - 0 (h) MEK bp = 79.5 ° C 0 0 0 0 0 - - 0 (i) IPA bp = 83 ° C 0 0 0 0 0 - - 0 (j) EtOH b.p. = 78.4 ° C 0 0 0 40 twenty - - 0 (k) Acetone b.p. = 56.1 ° C 0 0 0 0 0 - - 0 Additive (B1) (l) BYK-011 0,0 0,0 0,0 0,0 0,0 - - 0,0 (m) BYK-349 0,0 0,0 0,0 0,0 0,0 - - 0,0 (B2) (n) Sodium formate 0.4 0.4 0,0 0,0 0,0 - - 0,0 (o) Sodium chloride 0.5 0.5 0,0 0,0 0,0 - - 0,0 (B3) (p) Pentaerythritol 0,0 0,0 0,0 0,0 0,0 - - 0,0 Cooling rate (q) Quick cooling at 3.1 ° C / s ○ ○ - - ○ (r) Fast cooling at 2.2 ° C / s - - (s) Slow cooling at 1.1 ° C / s ○ ○ ○ - - Carrier Metal Foil (t) 70 μm aluminum ○ ○ ○ ○ (u) 100 μm aluminum ○ ○ ○ ○ Drill Tip Diameter (v) 0.08 mm ϕ ○ ○ (w) 0.105 mm ϕ ○ ○ (x) 0.15 mm ϕ ○ ○ ○ ○

Table 2-4 No. C29 C30 C31 C32 C33 C34 C35 C36 Polymer type (but) ALTOPMG150 - 90 90 80 80 80 one hundred 80 (b) ALKOX L11 - 0 0 0 0 0 0 0 (from) PEG20000 - 10 10 twenty twenty twenty 0 twenty (d) PEG4000 - 0 0 0 0 0 0 0 (e) PAOGENPP-15 - 0 0 0 0 0 0 0 Solvent (f) Water - one hundred one hundred one hundred one hundred one hundred one hundred 80 (g) MeOH b.p. = 64.7 ° C - 0 0 0 0 0 0 0 (h) MEK bp = 79.5 ° C - 0 0 0 0 0 0 0 (i) IPA bp = 83 ° C - 0 0 0 0 0 0 0 (j) EtOH b.p. = 78.4 ° C - 0 0 0 0 0 0 twenty (k) Acetone b.p. = 56.1 ° C - 0 0 0 0 0 0 0 Additive (B1) (l) BYK-011 - 0,0 0,0 0,0 0,0 0,0 0,0 0,0 (m) BYK-349 - 0,0 0,0 0,0 0,0 0,0 0,0 0,0 (B2) (n) Sodium formate - 0,0 0,0 0,0 0,0 0,0 0,0 0,0 (o) Sodium chloride - 0,0 0,0 0,0 0,0 0,0 0,0 0,0 (B3) (p) Pentaerythritol - 0,0 0,0 0,0 0,0 0,0 0,0 0,0 Cooling rate (q) Quick cooling at 3.1 ° C / s - ○ ○ ○ ○ ○ ○ (r) Fast cooling at 2.2 ° C / s - (s) Slow cooling at 1.1 ° C / s - Carrier Metal Foil (t) 70 μm aluminum ○ ○ ○ ○ ○ (u) 100 μm aluminum ○ ○ ○ Drill Tip Diameter (v) 0.08 mm ϕ ○ (w) 0.105 mm ϕ ○ ○ ○ ○ (x) 0.15 mm ϕ ○ ○ ○

Assessment Methods

For each of the drill stencil samples obtained in the Examples and Comparative Examples, the following property evaluations were performed.

Drilling procedure

To evaluate the properties of each of the obtained samples, drilling was carried out under the following conditions.

When drilling with a drill, the tip diameter of which was 0.15 mm ϕ, each sample was placed on top of a pack of four superimposed sheets of copper-clad multilayer material 0.2 mm thick (CCL-HL832, copper foil, both surfaces 12 μm, supplied by Mitsubishi Gas Chemical Company, Inc.) so that the layer of the water-soluble polymer composition is the topmost layer; a stack of sheets of copper-clad laminated material stacked on top of each other was placed on an auxiliary board (bakelite board) and 20 drills were performed, including 3000 holes for one drill tip, with the following parameters: diameter of the drill tip 0.15 mm (NED L004 0.15 × 2.5, supplied by Union Tool Co.), a rotation speed of 200,000 rpm and a feed speed of 20 μm / revolution.

When drilling with a drill with a tip diameter of 0.105 mm, each sample was placed on top of a pack of six superimposed sheets of copper-clad multilayer material 0.1 mm thick (CCL-HL832HS, copper foil, both surfaces 5 μm supplied by Mitsubishi Gas Chemical Company, Inc.) so that the layer of the water-soluble polymer composition is the topmost layer; a stack of sheets of copper-clad laminated material stacked on top of each other was placed on a support plate (bakelite plate), and 20 drills were performed, including 3000 holes for one drill tip, with the following parameters: drill tip diameter 0.105 mm (KMS L518 0.105 × 1, 8, supplied by Union Tool Co.), a rotation speed of 330,000 rpm and a feed speed of 8 μm / revolution.

When drilling with a drill, the tip diameter of which was 0.08 mm, each sample was placed on top of a pack of four superimposed sheets of multilayer material clad with copper, 0.1 mm thick (CCL-HL832HS, copper foil, both surfaces 5 μm, supplied Mitsubishi Gas Chemical Company, Inc.) so that the layer of the water-soluble polymer composition is the topmost layer; a stack of sheets of copper-clad laminated material stacked on top of each other was placed on an auxiliary board (bakelite plate) and 20 drills were performed, including 3,000 holes for one drill tip, with the following parameters: drill tip diameter 0.08 mm (KMV J948 0.08 × 1.2, supplied by Union Tool Co.), a rotation speed of 330,000 rpm and a feed speed of 6 μm / revolution.

Test 1

Hole accuracy

The offset of the location of the holes relative to the required coordinates when drilling 3,000 holes was determined on the back surface of the bottom plate of a stack of sheets of copper-clad laminated material superimposed on each other using an aperture analyzer (model NA-1AM, supplied by Hitachi Via Mechanics, Ltd.), the average value was calculated and standard deviation (σ) for one tip of the drill and calculated "average + 3σ". Then calculated the average value from the "average + 3σ" for 20 drills.

The results of evaluating the accuracy of the location of the holes are presented in Table 3. Additionally, Figures 4-6 show the dependences of the accuracy of the location of holes on the average size of crystalline grains, standard deviations of the average size of crystalline grains, and surface roughness Sm, respectively.

Test 2

Amount of polymer adhering to the drill

After drilling 3,000 holes, each of the 20 drill tips was examined under a 25x microscope (Model VHK-100 supplied by Keyence Corporation), determining the amount of polymer adhering to the drill compared to the diameter of the drill tip. Evaluation of the results was performed based on the criteria listed below; evaluation results are presented in Table 3.

○: The maximum diameter together with the polymer adhering to the drill is less than 1.5 times the diameter of the drill tip

Δ: The maximum diameter together with the polymer adhering to the drill is at least 1.5 times the diameter of the drill tip

×: The polymer adhering to the drill around the tip of the drill is split off and settles on the surface of the stencil during drilling

Test 3

Number of breakdowns of the drill tips

Drilling was carried out using 20 drill tips, and the number of breakages of the drill tips was determined. The resulting number of breakdowns of the drill tips is presented in Table 3.

Based on the above Tests 1-3, a comprehensive assessment was made in accordance with the criteria listed below:

: средний размер кристаллических зерен - не более 40 мкм / стандартное отклонение среднего размера кристаллических зерен - не более 17 мкм / шероховатость Sm поверхности - не более 7 мкм, смещение расположения отверстий - не более 23 мкм, отсутствие поломок наконечников сверла, отсутствие полимера, налипшего на сверло

: average size of crystalline grains - not more than 40 microns / standard deviation of the average size of crystalline grains - not more than 17 microns / surface roughness Sm - not more than 7 microns, hole displacement not more than 23 microns, no breakage of drill tips, no polymer sticking to the drill

○: average size of crystalline grains - not more than 70 microns / standard deviation of the average size of crystalline grains - not more than 25 microns / surface roughness Sm - not more than 8 microns, hole displacement - not more than 25 microns, no breakage of drill tips, no polymer, stuck to the drill

Δ: Average crystal grain size / standard deviation of the average crystal grain size / roughness Sm of the surface does not meet the specified requirements, the displacement of the holes is not more than 25 μm, there is no breakage of the drill tips, there is no polymer adhering to the drill

×: The average size of crystalline grains / standard deviation of the average size of crystalline grains / roughness Sm of the surface does not meet the specified requirements, the offset location of the holes is more than 25 μm, there is no breakage of the tips of the drill, there is no polymer adhering to the drill

×Ч: Average crystal grain size / standard deviation of the average crystal grain size / surface roughness Sm does not meet the specified requirements, there are breakages in the drill tips or polymer sticking to the drill

Table 3 No. Result Rating The average size of crystalline grains (microns) Standard deviation of the average crystal grain size (μm) Roughness Sm Surface (μm) (one) (2) (3) Comprehensive Assessment Hole Accuracy from Wed + 3σ (μm) Drill tip breakage Polymer sticking to the drill bit E1 28.5 9.85 3.2 21,2 ○ ○

E2 18.2 3.92 3.6 19.5 ○ ○

E3 20.1 5.00 3.9 20.6 ○ ○

E4 37.9 7.66 4.0 22.5 ○ ○

E5 18.7 5.93 4.1 18.8 ○ ○

E6 18.5 4,55 4.3 21,4 ○ ○

E7 39.6 8.64 4.6 22.1 ○ ○

E8 14,4 4.06 5.1 24.5 ○ ○ ○ E9 58.3 23.05 5.1 24.9 ○ ○ ○ E10 34,4 8.19 5.2 20.3 ○ ○

E11 21.3 6.00 5.9 21.1 ○ ○

E12 39,4 7.86 5.9 21,4 ○ ○

E13 17.3 4.14 6.2 18.9 ○ ○

E14 66.9 15.67 6.6 20.9 ○ ○ ○ E15 58.4 17.04 6.7 20,4 ○ ○ ○ E16 19.6 7.52 6.8 20.3 ○ ○

E17 55.1 19.28 6.8 21.3 ○ ○ ○ E18 40.1 12.25 6.9 23.7 ○ ○ ○ E19 61.1 12.08 7.3 20.6 ○ ○ ○ E20 18.5 4,55 4.3 14.2 ○ ○

C1 69.2 28.05 4.1 24.6 ○ ○ Δ C2 70.9 29.52 4.3 26.5 ○ ○ × C3 61.7 26.11 5,4 27.9 ○ ○ × C4 67.2 28.00 5.9 24.6 ○ ○ Δ C5 62.1 26.83 6.2 23.8 ○ ○ Δ C6 88.2 32,40 6.2 23.3 ○ ○ Δ C7 79.1 30.57 6.3 22.2 ○ ○ Δ C8 69.7 27.13 6.8 20.9 ○ ○ Δ C9 75.6 30.64 7.8 25.6 ○ ○ × C10 90.2 34.68 8.1 25.1 ○ ○ × C11 52,2 23.04 8.2 25,2 ○ ○ × C12 80.9 21.57 8.7 26.5 ○ ○ × C13 53.0 15.18 8.8 26.8 ○ ○ × C14 52,5 13.54 9.3 26.5 ○ ○ × C15 32.1 12.90 9.5 21,4 ○ ○ Δ C16 54.8 19.36 9.6 24.5 ○ ○ Δ C17 65,4 18.91 9.6 22.1 ○ ○ Δ C18 37.9 12.59 9.8 27.1 ○ ○ × C19 61,4 21.24 10.5 26.8 ○ ○ × C20 83.1 29.53 13.7 27.7 ○ ○ × C21 37.7 10.97 8.8 15.8 ○ Δ ×Ч C22 37.7 10.97 8.8 25.5 ○ Δ ×Ч C23 170.3 53.28 9.7 27.9 ○ Δ ×Ч C24 61,4 21.24 10.5 17.7 ○ Δ ×Ч C25 199.6 51.09 11,4 25,2 ○ Δ ×Ч C26 87.9 30.88 11.5 21,2 ○ Δ ×Ч C27 69.9 19.33 11.9 26.8 ○ Δ ×Ч C28 135.7 54.44 12.3 28.6 ○ Δ ×Ч C29 243.2 86.60 17.6 25.7 ○ Δ ×Ч C30 274.0 101.94 18.2 31.9 ○ Δ ×Ч C31 285.0 101.87 19.1 29.2 ○ Δ ×Ч C32 330.3 117.41 21,2 29.9 ○ Δ ×Ч C33 155.8 34.00 36,2 27.6 ○ Δ ×Ч C34 409.4 134.41 10.3 29.6 ○ × ×Ч C35 185.0 47.83 12.6 29.8 ○ × ×Ч C36 83.1 29.53 13.7 × × ×Ч

As can be seen from the data shown in Table 3, among the products of Comparative Examples 26, 27 and 29, which are commercially available traditional products, there are no products having a combination of small average crystalline grain sizes, small standard deviation of the average crystal grain size and low surface roughness Sm .

A comparison of the data shown in Table 3 in FIGS. 4-6 for the water-soluble polymer compositions used to obtain the samples of Examples 1-20, with the data obtained for the compositions of Comparative Examples 1-36, clearly shows the critical effect of the average crystal grain size , standard deviation of the average crystalline grain size and surface roughness Sm of the layer of water-soluble polymer composition on the accuracy of the location of the holes. In addition, it is obvious that the water-soluble polymer compositions of the samples obtained in Examples 1-20 provide good results in terms of polymer sticking to the drill and breakage of the drill tips compared to the materials of Comparative Examples 1-36.

In addition, it is obvious that if the average crystal grain size of the water-soluble polymer composition and the standard deviation of the grain size are small, high hole accuracy can be obtained, and low roughness values Sm of the stencil surface provide a reduction in the amount of polymer adhering to the drill bit.

Table 4 below shows the results of drilling tests using the materials of Example 20 and Comparative Example 21 with a drill tip diameter of 0.08 mm, taken from Tables 2 and 3;

the results of drilling with a drill bit with a tip diameter of 0.08 mm shown in Table 4 show that suitable values of the average crystal grain size and standard deviations of grain size, surface roughness Sm, hole accuracy and polymer adhesion to the drill can be obtained using materials in the manufacture of which was used rapid cooling of the layer of water-soluble polymer composition.

Table 4-1 No. E20 C21 Polymer type (a) ALTOP MG150 80 80 (a) PEG20000 twenty twenty Solvent (f) Water 90 90 (g) MeOH b.p. = 64.7 ° C 10 10 (j) EtOH b.p. = 78.4 ° C 0 0 Additive (B2) (n) Sodium formate 0.4 0.4 (o) Sodium chloride 0.5 0.5 Cooling rate (q) Quick cooling at 3.1 ° C / s ○ (s) Slow cooling at 1.1 ° C / s ○ Carrier Metal Foil (t) 70 μm aluminum ○ ○ Drill Tip Diameter (v) 0.08 mm ϕ ○ ○

Table 4-2 No. Physical property assessment result Physical property assessment result Comprehensive Assessment The average size of crystalline grains (microns) Standard deviation of the average crystal grain size (μm) Roughness Sm Surface (μm) Hole Accuracy from cf. + 3σ (μm) Drill tip breakage Polymer sticking to the drill bit E20 18.5 4,55 4.3 14.2 ○ ○

C21 37.7 10.97 8.8 15.8 ○ Δ ×Ч

The following Table 5 shows the drilling test results using the materials of Examples 5 and 6 and Comparative Example 22 with a drill tip diameter of 0.105 mm, taken from Tables 2 and 3; the results of drilling with a drill with a tip diameter of 0.105 mm shown in Table 5 show that suitable values of the average size of crystalline grains and standard deviations of grain size, surface roughness Sm, the accuracy of the location of holes and the sticking of polymer to the drill can be obtained using materials that were used to make rapid cooling of a layer of a water-soluble polymer composition was used.

Table 5-1 No. E5 E6 C22 Polymer type (a) ALTOP MG150 80 80 80 (a) PEG20000 twenty twenty twenty Solvent (f) Water 90 90 90 (g) MeOH b.p. = 64.7 ° C 10 10 10 (j) EtHO b.p. = 78.4 ° C 0 0 0 Additive (B2) (n) Sodium formate 0.4 0.4 0.4 (o) Sodium chloride 0.5 0.5 0.5 Cooling rate (q) Quick cooling at 3.1 ° C / s 0 0 (s) Slow cooling at 1.1 ° C / s 0 Carrier Metal Foil (t) 70 μm aluminum 0 0 0 Drill Tip Diameter (v) 0.105 mm ϕ 0 0 0

Table 5-2 No. Physical property assessment result Physical property assessment result Comprehensive Assessment The average size of crystalline grains (microns) Standard deviation of the average crystal grain size (μm) Roughness Sm Surface (μm) Hole Accuracy from cf. + 3σ (μm) Drill tip breakage Polymer sticking to the drill bit E5 18.7 5.93 4.1 18.8 ○ ○

E6 18.5 4,55 4.3 21,4 ○ ○

C22 37.7 10.97 8.8 25.5 ○ Δ ×Ч

The invention provides the possibility of obtaining a stencil for drilling holes, the use of which provides high accuracy of the location of the holes, less polymer adhering to the tip of the drill, and a lower frequency of breakage of the tip of the drill compared to using a traditional template for drilling holes. Drilling with high accuracy the location of holes of very small diameters, which were traditionally obtained only by laser processing, reducing the sticking of polymer to the drill tip and reducing the frequency of breakage of the drill tip are very important for industrial production, as this contributes to a decrease in cost and increase production productivity.

Numerical designations:

one Drill tip 2, 20 Layer of polymer composition 3 Carrier Metal Foil

Claims (6)

1. A stencil for drilling holes containing a layer of crystallizable water-soluble polymer composition, the thickness of which is from 0.02 to 0.3 mm, formed on at least one surface of the carrier metal foil, in which the average crystal grain size of the water-soluble polymer composition is from 5 up to 70 μm, and the standard deviation of the grain size is not more than 25 μm, the surface roughness Sm at the point of insertion of the drill tip into the layer of a water-soluble polymer composition is not more 8 μm, the layer of the water-soluble polymer composition obtained by applying directly to the supporting metal foil hot melt of the water-soluble polymer composition or by applying a solution containing the water-soluble polymer composition, followed by drying, followed by cooling, including temperature reduction from values from 120 ° C up to 160 ° C, to values ranging from 25 ° C to 40 ° C, for 60 seconds at a cooling rate of at least 1.5 ° C / s. 2. The stencil according to claim 1, in which the average crystal grain size of the water-soluble polymer composition is from 5 to 40 μm, and the standard deviation of the grain size is not more than 17 μm, and the surface roughness Sm of the layer of water-soluble polymer composition at the point of entry of the drill tip is not more than 7 microns. 3. The stencil according to claim 1, in which the water-soluble polymer composition contains a water-soluble polymer (A) and further comprises at least one substance selected from a hydrophobic material (B1), material (B2) having a melting point higher than the melting temperature of the water-soluble polymer (A) and material (B3) that improves compatibility with the water-soluble polymer (A). 4. The stencil according to claim 1, in which the solution containing the water-soluble polymer composition further comprises water and a solvent whose boiling point is lower than the boiling point of water. 5. The stencil according to claim 1, in which the thickness of the carrier metal foil is from 0.05 to 0.5 mm 6. The stencil according to claim 1, which is intended for processing multilayer materials clad with copper.

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