JP4610274B2 - Manufacturing method of electronic parts - Google Patents

Description

  The present invention relates to a method for manufacturing an electronic component such as a multilayer capacitor or a multilayer ceramic wiring board.

  In recent years, with the miniaturization of electronic devices, there has been a demand for miniaturization and high performance in electronic components such as multilayer capacitors and multilayer ceramic wiring boards. Such an electronic component is formed by adding an organic binder, a plasticizer, a solvent, etc. to ceramic powder to form a slurry, forming a ceramic green sheet with a doctor blade, etc., and then printing a conductive paste containing metal powder. A ceramic green sheet laminate is obtained by forming a conductor layer on the ceramic green sheet, and then laminating and pressing the ceramic green sheets on which a plurality of conductor layers are formed. It is obtained by firing the laminate.

  In response to the demand for higher functionality for electronic components, this multilayer ceramic wiring board is required to have particularly high dimensional accuracy. This is a mask that prints solder paste on the connection conductor on the surface of the multilayer ceramic wiring board when mounting chip components such as IC chips and chip capacitors on the multilayer ceramic wiring board when there are dimensional variations in the multilayer ceramic wiring board This is because there is a problem in that it is necessary to prepare a plurality of conductors in accordance with the dimensions, or when mounting by an automatic machine based on the outer periphery of the multilayer ceramic wiring board, it cannot be mounted accurately on the connection conductor on the surface of the multilayer ceramic wiring board. .

  Two methods have been proposed for this problem. (1) A method of applying pressure to the ceramic ceramic green sheet laminate during firing and suppressing the shrinkage of the ceramic green sheet laminate to a predetermined degree by the pressure; and (2) on both sides or one side of the ceramic green sheet laminate, In this method, constrained green sheets that do not substantially shrink at the firing temperature of the ceramic component of the ceramic green sheets are laminated and fired to prevent shrinkage in the longitudinal and lateral directions of the ceramic green sheet laminate.

  As a method of (1), according to Patent Documents 1 and 2, during the firing, the pressure is continuously applied to the surface of the ceramic green sheet laminated body in time, and the pressure is applied to the ceramic green sheet laminated body. A method is shown in which a ceramic green sheet laminate is fired to reduce the shrinkage in the XY plane to a predetermined level and to remove distortion such as warpage of the ceramic sintered body. As for the above pressure, it is shown that the average shrinkage rate in the X and Y directions of the surface layer can be made zero when the applied pressure is 10 to 350 MPa.

  As a method of (2), Patent Documents 3 to 5 disclose that an inorganic material that does not sinter at the firing temperature of the ceramic component in the ceramic green sheet, an organic binder, and a plasticizer on both surfaces or one surface of the ceramic green sheet laminate. A method of laminating and firing a constrained green sheet containing an organic component such as the above has been proposed. According to this restraint firing method, in order to restrain the shrinkage at the time of firing, shrinkage occurs only in the thickness direction of the ceramic green sheet laminate, and shrinkage does not occur in the longitudinal direction and lateral direction of the laminated surface, and the firing shrinkage This suppresses the dimensional variation of the ceramic substrate caused by the variability and improves the dimensional accuracy of the glass ceramic substrate.

  However, the manufacturing methods of (1) and (2) described above that suppress or prevent sintering shrinkage in the vertical and horizontal directions of the laminated surface are reasonable when manufacturing a large number of ceramic substrates. Productivity is not considered much. For example, in the method (1) of firing while applying pressure, since the applied pressure is as large as about 10 to 350 MPa, it is necessary to perform firing in a firing furnace having a pressurizing mechanism, which is not suitable for mass production. In the method (2) using the constrained green sheet, removal of the constrained green sheet after firing is necessary for the thickness of the sheet, and these become waste.

Therefore, Patent Document 6 that solves the problem of productivity has been proposed. According to Patent Document 6, an inorganic material that does not sinter at the firing temperature of the ceramic component is applied to the ceramic base plate, and a ceramic green sheet laminate is pressure-bonded to the coated surface side to form a crimped body and fired. In this case, it is possible to restrain the shrinkage of the ceramic green sheet laminate during firing only by placing a slight weight, and after firing, there is an inorganic material that does not sinter between the glass ceramic substrate and the ceramic base plate. The glass ceramic substrate and the ceramic base plate can be separated relatively easily.
JP-A-62-260777 Japanese Patent Laid-Open No. 5-283272 JP-A-4-243978 Japanese Patent Laid-Open No. 5-28867 JP-A-5-102666 JP 2000-26167 A

  However, an inorganic material that is not sintered at the firing temperature of the glass ceramic component is applied to the ceramic floor, and the ceramic green sheet laminate is pressure-bonded to the coated surface to form a pressed body and fired. However, due to the thickness variation that occurs after coating, there is a problem in that the ceramic green sheet laminate partially undergoes shrinkage variation due to firing, resulting in partial warping and waviness. For example, when it is applied to the entire surface of the ceramic base plate with a slightly larger area than the ceramic base plate, the coating liquid flows out to the side surface of the ceramic base plate, thereby reducing the coating thickness of the end surface portion of the ceramic base plate. Conversely, when the coating is applied in a slightly smaller area than the ceramic base plate, the thickness of the boundary portion of the coating layer increases due to the surface tension of the coating solution. This change in coating thickness can be ignored when the coating thickness is as thick as several hundreds μm. However, when the coating thickness is as thin as about 20 to 30 μm, the change in coating thickness cannot be ignored.

  In addition, the ceramic green sheet laminate and the ceramic base plate are pressure-bonded so that it is not necessary to place the ceramic green sheet laminate on the ceramic base plate during firing, but the raw ceramic green sheet laminate and the fired ceramic base plate are elastic. However, it is difficult to uniformly press the ceramic green sheet laminate without deformation. For example, when pressure bonding is performed by a press machine at 130 ° C. and 20 MPa, the pressure is not uniformly transmitted to the ceramic green sheet laminate when the press pressure rises due to a slight difference between the plane of the upper and lower punches and the plane of the ceramic base plate. The locally high part of the plate causes elastic deformation. As a result, when pressure is applied to 20 MPa, the ceramic green sheet laminate is partially deformed. Therefore, in the above method, although the dimensional variation due to the firing shrinkage variation can be suppressed, there is a problem in that the dimensional variation occurs due to deformation when the ceramic base plate and the ceramic green sheet laminate are pressure-bonded.

  The present invention has been completed in view of the above-mentioned conventional problems, and the object thereof is to produce a high-dimensional precision electronic component in a rational manner with a small amount of waste. It is providing the manufacturing method of the electronic component which can be performed.

In the method for producing an electronic component of the present invention, a constrained green sheet that does not substantially contract at the firing temperature of the ceramic green sheet laminate is placed on the ceramic base plate, and then on each of the upper and lower surfaces of the ceramic green sheet laminate, Firing in a state where the ceramic base plate is placed so that the constrained green sheet is in contact with the upper and lower surfaces, and then the ceramic fired body as an electronic component and the ceramic base plate are separated, The constrained green sheet contains a melting component that is in a molten state when the firing temperature is raised, and the heating during the firing temperature rise causes the molten component to be in a molten state and the restraining green sheet is softened, The ceramic green sheet laminate is deformed to follow the shape of the upper and lower surfaces of the ceramic green sheet laminate, Serial shrinkage of the ceramic green sheet and laminate adheres integrally to said ceramic green sheet laminate is characterized Rukoto constrained.

  The electronic component manufacturing method of the present invention is preferably characterized in that the melting component has a melting point of 35 to 100 ° C.

  According to the method for manufacturing an electronic component of the present invention, since the constrained green sheet contains a melting component that melts when heated, the constrained green sheet is softened at the beginning of the temperature rise in the firing step, and the surface of the ceramic green sheet laminate is Since the deformation follows the shape, the constrained green sheet and the ceramic green sheet laminate are in close contact with each other without generating a gap between the constrained green sheet.

  Further, since the constrained green sheet is prepared on a smooth carrier by preparing a slurry and using a doctor blade method or the like, the thickness variation of the constrained green sheet is small. Therefore, the ceramic green sheet laminate is partially subjected to shrinkage variation due to firing and does not cause partial warping or undulation.

  In addition, since the constrained green sheet is softened only by heating and has adhesiveness, there is no need to press the ceramic base plate and the ceramic green sheet laminate by pressure, and between the ceramic base plate and the ceramic green sheet laminate. It only needs to be put in and does not need to be pressurized. The ceramic green sheet laminate and its surface shape are deformed by the pressurization for producing the pressure-bonded body because the ceramic floor plate and the ceramic green sheet laminate can be adhered without gaps by softening the restrained green sheet by its own weight and heating. There is nothing. Therefore, since the constrained green sheet and the ceramic green sheet laminate that are softened at the initial stage of the temperature rise in the firing process are in close contact with each other, the shrinkage of the ceramic green sheet laminate is constrained by the constrained green sheet. Substantially no firing shrinkage and firing shrinkage variation can be suppressed. As a result, the ceramic sintered body obtained by firing has a high dimensional accuracy without deformation.

  Further, the shrinkage of the ceramic green sheet laminate is constrained so that the shrinkage of both main surfaces (upper and lower surfaces) is substantially the same without firing shrinkage. Therefore, the warp caused by the shrinkage mismatch between both main surfaces and the undulation caused by the partial shrinkage mismatch do not occur.

  Further, in the present invention, when a melting component of the constrained green sheet having a melting point of 35 to 100 ° C. is used, the constrained green sheet does not soften and deform at room temperature, so that the handling up to the firing process is easy. At the same time, organic components such as an organic binder (hereinafter also referred to as a binder) and a plasticizer in the ceramic green sheet are not decomposed during heating at the early stage of temperature increase in the firing step. Therefore, there is no gap between the constrained green sheet and the ceramic green sheet laminate due to the cracked gas, and the constrained green sheet is peeled off during the firing process, making it impossible to restrain firing shrinkage. This is more preferable because the restraining force is not uniform due to peeling and the fired electronic component is not deformed.

  The method for manufacturing an electronic component of the present invention will be described in detail below. FIGS. 1A and 1B are cross-sectional views for each process showing an example of an embodiment of a method for manufacturing an electronic component according to the present invention, wherein 1 is a ceramic base plate, 2 constrained green sheets, and 3 is a ceramic green sheet. The laminate 4 is a conductor layer.

  First, the ceramic base plate 1 whose main component is an inorganic material that is not sintered at the sintering temperature of the ceramic green sheet laminate 3 is prepared. The ceramic base plate 1 is preferably reused many times from the viewpoint of high productivity. Therefore, the main component of the ceramic base plate is preferably a high-purity alumina which is an oxide having a high melting point and is chemically stable. .

  The thickness of the ceramic base plate 1 is preferably as thick as possible because warping is likely to occur when it is repeatedly reused and fired. However, if the thickness is too thick, volatilization of decomposed organic components may be hindered. There is sex. Therefore, for example, it is preferable to use porous alumina that does not hinder the volatilization of organic components, and to use a thickness of about 5 mm that does not deform even after repeated firing.

Next, the constraining green sheet 2 is mainly composed of a hardly sinterable inorganic material such as Al ₂ O ₃ , ZrO ₂ , SiO ₂ or the like that does not substantially shrink at the sintering temperature of the ceramic green sheet laminate 3. Add a solvent (organic solvent, water, etc.) to inorganic powder, binder, and melted components, and if necessary, add a specified amount of plasticizer and dispersant to obtain a slurry. Is obtained by molding.

  Here, “substantially does not shrink” means that the shrinkage of the constraining green sheet 2 in the XY plane direction is suppressed to 1% or less, preferably 0.8% or less, more preferably 0.5% or less. means. The “XY plane” refers to a plane defined by the X direction and the Y direction when the thickness direction of the constraining green sheet 2 is the Z direction in three-dimensional coordinates.

  As the binder blended in the constraining green sheet 2, those conventionally used for ceramic green sheets can be used. For example, acrylic (acrylic acid, methacrylic acid or ester homopolymer or copolymer thereof) , Concretely acrylic acid ester copolymer, methacrylic acid ester copolymer, acrylic acid ester-methacrylic acid ester copolymer, etc.), polyvinyl butyral, polyvinyl alcohol, acrylic-styrene, polypropylene carbonate And homopolymers or copolymers of cellulose and cellulose. In view of decomposition and volatility in the firing step, an acrylic binder is more preferable.

  The molten component contained in the constrained green sheet 2 is in a molten state when heated at the initial stage of temperature rise in the firing step, and includes hydrocarbons, fatty acids, esters, fatty alcohols, polyhydric alcohols, and the like. Considering the solubility in a solvent when preparing the slurry, hydrocarbons, esters, fatty alcohols and polyhydric alcohols having a small molecular weight and polarity are preferred. Further, in view of compatibility with the above-described acrylic binder, esters, fatty alcohols, and polyhydric alcohols are more preferable.

  Among the above-mentioned melting components, those having a melting point of 35 to 100 ° C. are preferable. When a material having a melting point in this range is used, the restraint green sheet 2 does not soften and deform at room temperature, so that it is easy to handle until the initial temperature rise in the firing process. The sheet 2 and the ceramic green sheet laminate 3 can be easily stacked. In addition, since organic components such as a binder and a plasticizer in the constrained green sheet 2 are not decomposed during heating at the initial stage of temperature increase in the firing step, the cracked gas causes the constrained green sheet 2 to be sandwiched between the ceramic green sheet laminate 3. No voids are generated. Specific examples of the melting component having a melting point of 35 to 100 ° C. include hexadecanol, polyethylene glycol, polyglycerol, stearylamide, oleylamide, ethylene glycol monostearate, paraffin, stearic acid, and silicone. .

  The content of the molten component contained in the constrained green sheet 2 varies depending on at least the binder component to be used and the amount thereof and the molten component to be used, but the constrained green sheet 2 is softened in a state where the molten component is melted. Or the quantity which deform | transforms following the shape of the ceramic green sheet laminated body 3 located in the bottom and the conductor layer 4 formed in the surface is required. In addition, the filling rate of the hardly sinterable inorganic material in the constrained green sheet 2 can be lowered by increasing the content of the molten component. As a result, the constrained green sheet 2 after firing has the advantage that the constrained green sheet 2 can be easily removed because the melted components and the organic binder are burned away, so that the constrained green sheet 2 can be easily removed. There is a disadvantage that the surface roughness of the sintered body becomes large.

If the thickness of the constrained green sheet 2 is a method using the conventional constrained green sheet (the method of (2) above), the thickness of the constrained green sheet 2 needs to be 10% or more with respect to the thickness of the ceramic green sheet laminate 3 only on one side. However, in the present invention, the ceramic base plate 1 and the constrained green sheet 2 are also brought into close contact with each other by heating at the initial stage of temperature rise in the firing step, so that the thickness of the ceramic base plate 1 is sufficiently 5 mm. Shrinkage is constrained. Accordingly, the thickness of the constrained green sheet 2 is formed on the ceramic base plate 1 and the ceramic green sheet laminate 3 positioned on or below the constrained green sheet 2 in a state where the molten component is melted and softened. Any thickness that can be deformed following the shape of the conductor layer 4 is acceptable. For example, the surface of the ceramic base plate 1 has almost no unevenness, but most of the surface unevenness of the ceramic green sheet laminate 3 is caused by the thickness of the conductor layer 4, so that the thickness of the conductor layer 4 is more than about 20 to 30 μm. It is sufficient if the thickness of the restraining green sheet 2 is slightly thick. Thereby, the quantity which the restraint green sheet 2 after baking removes becomes very small, and the amount of waste can be reduced.

  The ceramic green sheet laminate 3 is obtained by forming a ceramic green sheet and forming a conductor layer 4 thereon and aligning and stacking a desired number of sheets.

As the ceramic green sheet, a mixture of ceramic powder, a binder, a solvent and the like is used. Examples of the ceramic powder include glass ceramic powder (a mixture of glass powder and filler powder) in the case of a ceramic wiring board, and composite perovskite ceramic powder such as BaTiO ₃ system and PbTiO ₃ system in the case of a multilayer capacitor. And is appropriately selected according to the characteristics required for the electronic component.

Examples of the glass component of the glass ceramic powder include SiO ₂ —B ₂ O ₃ system, SiO ₂ —B ₂ O ₃ —Al ₂ O ₃ system, SiO ₂ —B ₂ O ₃ —Al ₂ O ₃ —MO system (however, , M represents Ca, Sr, Mg, Ba or Zn), SiO ₂ —Al ₂ O ₃ —M ¹ O—M ² O system (where M ¹ and M ² are the same or different, and Ca, Sr , Mg, Ba or Zn), SiO ₂ —B ₂ O ₃ —Al ₂ O ₃ —M ¹ O—M ² O system (where M ¹ and M ² are the same as above), SiO ₂ — B ₂ O ₃ —M ³ ₂ O system (where M ³ represents Li, Na or K, SiO ₂ —B ₂ O ₃ —Al ₂ O ₃ —M ³ ₂ O system (where M ³ is The same), Pb glass, Bi glass and the like.

Further, as the filler powder of the glass ceramic powder, for example, a composite oxide of Al ₂ O ₃ , SiO ₂ , ZrO ₂ and an alkaline earth metal oxide, a composite oxide of TiO ₂ and an alkaline earth metal oxide, A ceramic powder such as a composite oxide (for example, spinel, mullite, cordierite) containing at least one selected from Al ₂ O ₃ and SiO ₂ can be used.

  As the binder blended in the ceramic green sheet, those conventionally used in ceramic green sheets can be used as in the case of the constraining green sheet 2. In view of decomposition and volatility in the firing process, an acrylic binder is more preferable for the ceramic green sheet.

  Ceramic green sheets are obtained by adding a solvent (organic solvent, water, etc.) to the above ceramic powder, binder, and melted components, and if necessary, a predetermined amount of plasticizer and dispersant to obtain a slurry. It can be obtained by molding by the method, die coater method, etc.

  As a method of forming the conductor layer 4 on the ceramic green sheet, for example, a method of printing a conductor paste obtained by pasting a conductor material powder by a screen printing method or a gravure printing method, a plating method or a vapor deposition method, etc. There is a method of directly forming a metal film having a predetermined pattern shape by a method, or a method of transferring a metal film formed by printing, shape processing, plating, vapor deposition or the like in a predetermined pattern shape onto a ceramic green sheet. Examples of the conductive material include one or more of W, Mo, Mn, Au, Ag, Cu, Pd (palladium), Pt (platinum), etc., and in the case of two or more, mixing, alloy, layer Any form such as another coating may be used.

  Before forming the conductor layer 4, a through conductor such as a via-hole conductor or a through-hole conductor for connecting the upper and lower conductor layers 4 may be formed as necessary. This through conductor is formed by means such as embedding a conductive paste obtained by pasting a conductive material powder into a through hole formed in a ceramic green sheet by punching, laser processing or the like by printing or press filling.

  As a method of laminating a desired number of ceramic green sheets on which the conductor layer 4 is formed, a pressing method can be mentioned. As the condition, thermocompression bonding by heating, adhesion with an adhesive, or the like can be considered.

  And as shown to Fig.1 (a), it laminates | stacks in order of the ceramic base plate 1, the restraint green sheet 2, the ceramic green sheet laminated body 3, the restraint green sheet 2, and the ceramic base plate 1, and it bakes.

  The firing process includes an organic component removal process and a ceramic powder sintering process. The removal of the organic component is performed by heating the ceramic green sheet laminate 3 in a temperature range of 100 to 800 ° C. to decompose and volatilize the organic component. The sintering temperature varies depending on the ceramic composition and is performed within a range of about 800 to 1600 ° C. The firing atmosphere varies depending on the ceramic powder and the conductor material, and is performed in the air, in a reducing atmosphere, in a non-oxidizing atmosphere or the like, and may contain water vapor or the like in order to effectively remove organic components.

  Also, during firing, a weight is applied to the upper surface of the uppermost ceramic base plate 1 in order to assist the adhesion of the ceramic base plate 1, the constraining green sheet 2 and the ceramic green sheet laminate 3 and to prevent warping. A load may be applied, for example, by placing it. As the weight, it is preferable to use, for example, porous ceramics or metal so as not to prevent volatilization of the decomposed organic component. A porous weight may be placed on the upper surface of the ceramic green sheet laminate 3, and a non-porous weight may be placed thereon. Moreover, it is good also as a substitute for weight by making the thickness of the ceramic floor board 1 thick, and the effect of the assistance of contact | adherence and prevention of curvature similarly is acquired.

  At the beginning of the temperature rise of firing, the constrained green sheet 2 softens because it contains a melting component that melts upon heating, and deforms following the shape of the surface of the ceramic green sheet laminate 3 as shown in FIG. Therefore, the constraining green sheet 2 and the ceramic green sheet laminate 3 are in close contact with each other without generating a gap between the constraining green sheet 2.

  Further, the constraining green sheet 2 is softened only by heating and has adhesiveness. Therefore, the constraining green sheet 2 only needs to be placed between the ceramic floor plate 1 and the ceramic green sheet laminate 3 and does not require pressure. Since the ceramic floor plate 1 and the ceramic green sheet laminate 3 can be adhered without any gap by softening the self-weight of the ceramic green sheet laminate 3 and the constrained green sheet 2 by heating, the ceramic green sheet laminate 3 and its surface can be applied by pressurization for producing a crimped body. The shape does not deform. Therefore, since the constrained green sheet 2 softened at the initial stage of heating in the firing step and the ceramic green sheet laminate 3 are in close contact with each other, the shrinkage of the ceramic green sheet laminate 3 is constrained by the constrained green sheet 2. The sheet laminate 3 is not substantially fired and shrunk and variation in firing shrinkage is suppressed, and the obtained ceramic fired body has a high dimensional accuracy without deformation.

  Further, when the melting component of the constraining green sheet 2 having a melting point of 35 to 100 ° C. is used, the constraining green sheet 2 is not softened and deformed at room temperature, so that the handling up to the firing process becomes easy. At the same time, since organic components such as binders and plasticizers in the ceramic green sheet are not decomposed during heating at the beginning of the temperature rise in the firing process, voids are generated in the constrained green sheet 2 and the ceramic green sheet laminate 3 by the decomposition gas. In the middle of the firing process, the restraining green sheet 2 peels off, making it impossible to restrain firing shrinkage, or part of the restraining force makes the restraining force non-uniform and deforms the fired electronic component. This is more preferable.

  When applying a powder of a hardly sinterable inorganic material, which is a component of the constrained green sheet 2 that does not substantially shrink, to the ceramic floor plate 1 and pressing and firing the ceramic green sheet laminate 3 and the constrained green sheet 2, Sintering of the ceramic green sheet laminate 3 was substantially suppressed, but the dimensional accuracy of the electronic component obtained by sintering was about ± 0.5% (dimensional error). However, in the present invention, when the constrained green sheet 2 containing a molten component is used, the dimensional accuracy of the ceramic green sheet laminate 3 and the electronic component is ± 0.2% or less, and it is experimentally shown that found.

  The constrained green sheet 2 becomes a constrained layer by removing organic components by firing, but is very fragile and can be easily separated from the ceramic base plate 1. However, since the constraining layer is attached to the surface of the sintered ceramic body after firing, the constraining layer is removed. The removal method is not particularly limited as long as it can remove the constraining layer attached to the surface. For example, polishing, water jet, chemical blasting, sand blasting, wet blasting (a method of spraying abrasive grains and water by air pressure), etc. Is mentioned.

  Good connection to the surface of the conductive layer 4 exposed on the surface of the ceramic sintered body from which the constraining layer has been removed, for preventing the corrosion of the conductive layer 4 or to an external substrate such as solder or metal wire or other electronic components. Therefore, Ni or Au plating may be applied.

  Since the electronic component manufactured by the method as described above has high dimensional accuracy, high-density mounting required as an electronic component can be achieved and excellent electrical characteristics can be obtained.

(A), (b) is sectional drawing for every process which shows an example of embodiment of the manufacturing method of the electronic component of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Ceramic base plate 2 ... Restraint green sheet 3 ... Ceramic green sheet laminated body 4 ... Conductor layer

Claims (2)

A constrained green sheet that does not substantially shrink at the firing temperature of the ceramic green sheet laminate is placed on the ceramic floor plate, and then the constrained green sheet is in contact with the upper and lower surfaces of the ceramic green sheet laminate, respectively. In this way, the ceramic base plate is fired in a state where the ceramic base plate is installed, and then the ceramic fired body as the electronic component and the ceramic base plate are separated from each other. It contains a molten component that is sometimes in a molten state, and by heating at the time of firing, the molten component becomes a molten state and the constrained green sheet is softened, and the shape of the upper and lower surfaces of the ceramic green sheet laminate The ceramic base plate, the constraining green sheet and the ceramic green sheet Method of manufacturing an electronic component body and is in close contact integrated in the contraction of the ceramic green sheet laminate, wherein Rukoto constrained.   The method for manufacturing an electronic component according to claim 1, wherein the melting component has a melting point of 35 to 100 ° C.

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