JP2015074221A - Heat insulation die and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat insulation die having the conventional heat insulation layer made of a porous ferrite film effectively suppressing or preventing the deformation of the die surface under high pressure upon molding.SOLUTION: Provided is a die having a heat insulation layer between a die base material made of metal and a metal film composing a molding face, where, (1) the heat insulation layer includes 1) a porous film in which the crystal grains of ferrite are formed so as to be connected into a three-dimensional network shape and 2) a solid material filled at least into a part of gaps in the porous film, and the space between the heat insulation layer and the metal film is provided with a heat conduction layer having a heat conductivity of 100 W/m K or higher at 100°C.

Description

  The present invention relates to a heat insulating mold used for resin molding of, for example, optical elements and precision parts. More specifically, the present invention relates to a heat insulating mold for manufacturing a thin plate-like resin molded product such as a light guide plate.

  Many products such as optical elements and precision parts are made of synthetic resin moldings, but with the miniaturization and high functionality of the products, there is an increasing demand for precision molding technology. An example of such a product is a light guide plate.

  A light guide plate is a thin plate-like material used for display parts, such as a personal computer, a smart phone, and a tablet, for example. The light guide plate has the function of diffusing the light entered from the side surface and emitting uniform light on the surface, but in order to emit light efficiently and as designed, it forms precise and fine irregularities on the back surface There is a need.

  An example of a resin molding method for producing such a fine shape is injection molding. In injection molding, molten resin injected from a nozzle of an injection molding machine passes through a sprue, a runner, a gate, and the like and is filled into a cavity. Thereafter, by opening the mold, the resin molded product cooled and solidified in the cavity is taken out.

  Also in the formation of the light guide plate, by injection molding, molten resin is injected into a cavity made of a mold whose surface is processed with a fine concavo-convex pattern, cooled and solidified, and the fine concavo-convex pattern is transferred It is taken out as a resin molded product having a predetermined shape. That is, the mold gate (for example, side gate) causes the molten resin to flow through the space of the mold cavity with a thin and narrow gap from the groove on one side of the rectangular mold toward the opposite side, A light guide plate having a predetermined shape can be obtained by transferring a fine pattern on the transfer surface of the mold.

  More specifically, when injection molding a light guide plate or the like, a mold including a fixed mold and a movable mold is used, and molten resin is introduced into a cavity formed by the fixed mold and the movable mold. In this case, when the molten resin comes into contact with the mold surface, the surface of the flowing molten resin is cooled and a skin layer is generated. The molten resin flows on the surface of the fine concavo-convex pattern while being cooled by being deprived of heat energy by the mold surface. After the flow is finished and the molten resin has spread over the entire surface of the pattern, the movable mold is pushed in (that is, mold clamping), and by reducing the cavity, the resin with the skin layer formed on the surface of the mold pattern As a result of the pressing, a resin molded product to which the pattern is transferred can be obtained.

  However, in the conventional injection molding, there is a problem that as the transfer pattern of the mold becomes finer, it becomes more difficult to faithfully transfer (reproduce) the fine uneven pattern. This is because when the molten resin flows into the cavity of the mold, the surface of the flowing resin cools by contacting with the cold mold surface, which prevents the transfer. Contributed to this. For this reason, in order to prevent such a transfer failure, apparatus devise such as (i) increasing the temperature of the resin injected into the mold, (ii) heating the mold, (iii) increasing the pressure of mold clamping, etc. Has been made.

  In recent injection resin molding using a mold for molding a fine-shaped resin, in order to accurately transfer the shape of the molten resin that flows into the finely processed grooves deeply formed in the mold, a heat insulating mold is used. Valid (corresponding to (ii) above). In a normal mold (non-insulated mold), the heat energy of the high-temperature molten resin molded on the molding surface of the metal mold is deprived by the mold, resulting in the temperature of the molten resin dropping more than necessary. Whereas transfer defects occur, such heat transfer molds can effectively avoid such transfer defects.

  That is, in the heat insulating mold, since the heat insulating layer is arranged as a lower layer of the molding surface made of the metal film, the heat of the molten resin is not easily transmitted to the metal mold base material in the lower layer of the heat insulating layer. As a result, the temperature drop of the molten resin is suppressed. As a result, the high-temperature molten resin flows into a microfabrication pattern such as a deep groove formed on the mold surface while maintaining a low viscosity (that is, high fluidity). Therefore, the pattern shape can be accurately transferred.

  In the structure of the heat insulating mold, a heat insulating layer having low thermal conductivity and strength is arranged between a metal mold base material and a film forming a resin transfer surface. As the heat insulating layer, a ceramic material having a heat insulating effect and having a strength capable of withstanding a molding pressure during resin molding such as injection molding is selected. For example, a base material, a heat insulating layer provided on the base material by thermal spraying, an intermediate layer provided on the heat insulating layer, and a molding surface that covers the intermediate layer and molds an optical element. An optical element molding die having a surface layer is known (Patent Document 1).

  Moreover, in order to overcome problems such as workability of a heat insulating layer made of a sprayed film, the inventors of the present application formed ferrite ceramic crystal particles in a three-dimensional network as a heat insulating mold for a ceramic material. The invention which concerns on the heat insulation metal mold | die which has a heat insulation layer which consists of a porous membrane and has an infinitely fine space | gap has been proposed previously (patent document 2).

International Publication WO2007 / 020769 Patent No. 4966437

  However, there is room for further improvement in these heat insulating molds. That is, in the case of manufacturing a thin plate-shaped resin molded product such as a light guide plate, it is currently impossible to simply provide a heat insulating layer. The thinner the target resin molded product, the greater the influence of the skin layer due to cooling, and the greater the risk of molding defects even in a heat insulating mold.

  On the other hand, in order to suppress the influence of the cooling of the molten resin when using the heat insulating mold, a method of pouring the molten resin at a higher pressure in order to rapidly inject the molten resin into the mold can be considered. In that case, a heat insulating mold capable of withstanding repeated use under high pressure and high thermal shock is required, but such a heat insulating mold excellent in durability has not yet been developed. For this reason, even if the conventional heat insulation mold is used under high pressure and high thermal shock, the mold will be deformed immediately, making it difficult to reproduce complicated and fine patterns, and relatively short-term use. At present, it is necessary to change the mold.

  Therefore, a main object of the present invention is to provide a heat insulating mold that can transfer a pattern shape more accurately even if it is a thinner plate-like molded body and that is excellent in durability.

  As a result of intensive studies in view of the problems of the prior art, the present inventor has found that a heat insulating mold having a specific structure can achieve the above object, and has completed the present invention.

That is, this invention concerns on the following heat insulation metal mold | die.
1. A mold having a heat insulating layer between a metal mold base material and a metal film constituting the molding surface,
(1) The heat insulating layer includes: 1) a porous film formed by connecting ferrite crystal particles in a three-dimensional network; and 2) a solid material filled in at least a part of voids in the porous film. Including
(2) Between the heat insulating layer and the metal film, a heat conductive layer having a heat conductivity of 100 ° C. of 100 W / m · K or more is provided.
Insulation mold characterized by that.
2. The porous film is formed by hydrothermal synthesis reaction of 1) the surface of a metal mold base material or 2) the surface of a metal layer previously formed on the surface of the mold base material. The heat insulation mold according to Item 1 above.
3. The ferrite has the following general formula A _x Fe _3−x O ₄ (where A represents at least one metal element that can be substituted for the Fe site constituting the spinel-type iron oxide crystal, and x is 0 ≦ x <1. Meet)
Item 3. The heat-insulating mold according to Item 1 or 2, which is a compound having a spinel crystal structure represented by:
4). Item 4. The heat insulating mold according to Item 3, wherein A is at least one of Ca, Zn, Mn, Al, Cr, Li, and Mg.
5. Item 5. The heat insulating mold according to any one of Items 1 to 4, wherein the solid material is inorganic oxide glass.
6). Item 6. The inorganic oxide glass according to Item 5, wherein the inorganic oxide glass is at least one of 1) borosilicate glass, 2) silica glass, and 3) glass containing at least one of aluminum, titanium, zirconium, tin, and iron. Insulation mold.
7). Item 7. The heat insulating mold according to any one of Items 1 to 6, wherein the solid material is produced by impregnating the pores with a liquid raw material of an inorganic oxide and then heat-treating in an oxidizing atmosphere.
8). Item 8. The heat insulating mold according to Item 7, wherein the liquid raw material contains a precursor compound of an inorganic oxide and a solvent.
9. The heat insulation metal mold | die in any one of said claim | item 1-8 used for shaping | molding of the composition containing a resin component.

  According to the present invention, the following excellent effects can be obtained particularly because the heat insulating layer having a specific structure and the heat conductive layer formed thereon are provided.

  That is, in the planar direction (horizontal direction) of the heat insulating mold, a heat conductive layer is formed, so that excellent heat conductivity can be exhibited. For this reason, the metal film / insulation layer due to stress generated by the difference in thermal expansion (thermal expansion difference between the thermal energy transfer area and its surroundings) caused by local transfer of thermal energy of the molten resin injected at high pressure It is possible to effectively prevent the deterioration of the adhesion. On the other hand, in the vertical direction (vertical direction) of the heat insulating mold, the heat insulating layer can exhibit excellent heat insulating properties, and at the same time, since the heat insulating layer itself has high strength, the heat insulating layer itself has excellent durability. In addition, deformation of the heat conduction layer and the like due to the molten resin under high pressure can be effectively suppressed. As a result, it is possible to provide a heat insulating mold that can maintain the accuracy and reliability of transfer even after repeated use over a long period of time.

  More specifically, when resin molding that requires high molding pressure is performed compared to the conventional heat insulating mold, it is difficult to cause dents on the mold surface due to the deterioration of the strength of the heat insulating layer. At the same time, in a large-area, thin-plate shaped cavity, the molten resin reaches the arrival point while reducing the thermal shock while keeping the skin layer formed by cooling from the injection point thin, and accurately transfers complex fine shape patterns can do. As a result, the number of repeated molding of one mold can be significantly increased during resin molding, and as a result, the running cost (manufacturing cost of the resin molded product) is reduced by extending the life of the heat insulating mold. It becomes possible.

  The heat insulating mold of the present invention having such characteristics is particularly suitable for the production of a resin molded product having a fine shape. Therefore, it is useful for manufacturing optical components (prism sheet, light guide plate, optical disk such as CD / DVD disk, diffractive lens), and the like. In particular, it can be suitably used for the production of a thin plate-like resin molded product having a thickness of 3 mm or less, for example.

It is a schematic sectional drawing of the heat insulation metal mold | die in Example 1 of this invention. It is a figure which shows the preparation process of the heat insulation metal mold | die in Example 1 of this invention. It is a flowchart which shows the process of forming the heat insulation layer of the heat insulation metal mold | die in Example 1 of this invention. It is the schematic of the impregnation apparatus of the liquid raw material used for preparation of the heat insulation layer of the heat insulation metal mold | die in Example 1 of this invention. It is a figure which shows the X-ray-diffraction pattern of the heat insulation layer (a) of this invention in Example 1 of this invention, and the conventional heat insulation layer (b). It is the scanning electron microscope image of the surface and cross section of the heat insulation layer (a) of this invention in Example 1 of this invention, and the conventional heat insulation layer (b). It is a figure which shows the general | schematic cross-section block diagram of the measurement sample for thermal insulation evaluation in Example 1 of this invention. It is the schematic of the heat insulation evaluation apparatus in Example 1 of this invention. It is a figure which shows the heat insulation evaluation result of the heat insulation layer (a) of the heat insulation metal mold | die of this invention in Example 1 of this invention, and the conventional heat insulation layer (b). It is the perspective view and sectional drawing of the evaluation sample of the compressive strength of the heat insulation layer in Example 1 of this invention. It is the schematic of the evaluation apparatus of the compressive strength of the heat insulation layer in Example 1 of this invention. It is a graph which shows the relationship between the indentation pressure of the heat insulation layer of this invention in Example 1 of this invention, and the conventional heat insulation layer, and the amount of dents. It is the schematic of the evaluation apparatus of the heat conductivity of the heat conductive layer in Example 1 of this invention. It is a figure which shows the evaluation result of the heat conductive effect of the heat conductive layer in Example 1 and Example 2 of this invention. In FIG. 14, “(a)” indicates the first embodiment, and “(b)” indicates the second embodiment. It is a figure which shows the X-ray-diffraction pattern of each heat insulation layer in Example 2 and Example 4 of this invention. In FIG. 15, “(1)” indicates the second embodiment, and “(2)” indicates the fourth embodiment. It is a schematic perspective view of the resin molded product (light guide plate) which shape | molded molten resin using this invention metal mold | die. It is a figure which shows the process example in the case of shape | molding molten resin using this invention metal mold | die. It is a schematic diagram which shows an example of the layer structure of this invention metal mold | die. It is a schematic diagram which shows the structure of the heat insulation layer of this invention metal mold | die. In this invention, it is a schematic diagram which shows the method of measuring a porosity.

1, 61 Heat insulation mold 2, 62 Metal mold base material 3, 23, 43, 63 Metal layer 4, 24, 44, 64 Heat insulation layer 5, 25, 65 Bonding layer 6, 26, 56, 66 Heat conduction Layer 6a, 26a First heat conductive layer 6b, 26b Second heat conductive layer 7, 27, 57, 67 Metal film 7a First metal film 7b Second metal film 7s, 67s Precision machined surface 11 Impregnation device 12 Liquid material 13 Material Container 14, 21, 41, 51 Sample 15 Impregnation chamber 16, 18 Valve 17 Piping 19 Vacuum exhaust pump 20 Vacuum gauge 22 Metal base material 29 Thermocouple insertion hole
31 Thermal insulation evaluation device 32, 72 Comparative sample 33 Second comparative sample
34, 74 Electric heater 35, 75 Metal plate
36, 37, 38, 76, 77 Thermocouple 39, 79 Multi-temperature recorder 40, 80 Thermal insulation cover 42, 52 Substrate 45 Press test evaluation device 46 Sample stand 47 Mounting stand 48 Hydraulic cylinder 49 Piston rod 50 Pressing jig 62a Metallic metal Central region 62b of the upper surface of the mold base material 64b Peripheral region of the upper surface of the metal mold base material 64a Porous film 64b Solid material 71 Thermal conductivity evaluation device 73 Heat insulation plate 91 Light guide plate resin molded product 92 Light guide plate 93 Sprue portion 94 Runner Part 95 Gate part 101 Fixed mold 102 Movable mold 103 Frame part 104 Projection pin 105 Sprue 106 Runner 107 Cavity 108 Resin

1. Heat insulation mold The heat insulation mold of the present invention (the present invention mold) is a mold having a heat insulation layer between a metal mold base material and a metal film constituting a molding surface,
(1) The heat insulating layer includes: 1) a porous film formed by connecting ferrite crystal particles in a three-dimensional network; and 2) a solid material filled in at least a part of voids in the porous film. Including
(2) Between the heat insulating layer and the metal film, a thermal conductive layer having a thermal conductivity of 100 W / m · K or higher at 100 ° C. is provided.
It is characterized by that.

  As described above, the mold according to the present invention includes a metal mold base material, a heat insulating layer, a heat conductive metal layer, and a metal film as a basic structure, but includes other layers as necessary. Also good. Hereinafter, the configuration of each layer will be described.

  In the present invention, unless otherwise specified, “metal” includes an alloy, an intermetallic compound, and a metalloid in addition to a single metal. Further, the thermal conductivity in the present invention refers to a thermal conductivity of 1 atm and 100 ° C. unless otherwise specified.

  A schematic diagram of a configuration example of the mold of the present invention is shown in FIG. The heat insulation mold 61 of FIG. 18 has a metal mold base material 62, a heat insulation layer 64, a heat conduction layer 66, and a metal film 67 as a basic configuration.

  In this heat insulating mold 61, the heat insulating layer 64 is formed on the central region 62 a leaving the peripheral region 62 b on the upper surface of the metal mold base material 62 on the molding surface side. In FIG. 18, the center region 62a is designed to be higher than the surrounding region 62b. However, the center region and the surrounding region can be set at the same height.

  A schematic diagram of the basic structure of the heat insulating layer 64 is shown in FIG. FIG. 19 is an enlarged view of the three-layer structure portion of the metal mold base material 62, the heat insulating layer 64, and the bonding layer 65. The heat insulating layer 64 is composed of a porous film 64a in which ferrite crystal particles (crystalline particles) are connected in a three-dimensional network and a solid material (solid hard material) 64b contained in the voids. In other words, the heat insulating layer 64 has a structure made of a composite material in which the porous film 64a is a matrix (a skeleton having a predetermined strength) and the solid material 64b is a dispersing material. Thereby, while exhibiting the outstanding heat insulation, especially the intensity | strength in the thickness direction (vertical direction) of a heat insulation layer can be raised more.

  Moreover, the metallic layer 63 can also be formed between the metal mold base material 62 and the heat insulation layer 64 as needed, like this heat insulation mold. By providing the metallic layer, the adhesion (bondability) between the metal mold base material and the heat insulating layer can be further enhanced.

  In the heat insulating mold of FIG. 18, a bonding layer 65 is formed on the heat insulating layer 64, and a heat conductive layer 66 is further formed thereon. That is, in order to further improve the bonding property between the heat insulating layer 64 and the heat conductive layer 66, the bonding layer 65 may be provided as necessary. In particular, as shown in FIG. 18, it is desirable to form the bonding layer 65 so as to surround the upper surface and the side surface of the heat insulating layer 64. Further, it is desirable that both end portions of the bonding layer 65 are extended to a position lower than the lower surface of the heat insulating layer 64 as shown in FIG. 18 in order to further enhance the bonding effect.

  The metal film 67 is formed on the heat conductive layer 66. In this heat insulating mold, the metal film 67 is also formed so as to surround the upper surface and the side surface of the heat insulating layer 64 so as to follow the heat conductive layer 66. On the upper surface (molding surface) of the metal film 67, a precision processed surface 67s having a predetermined uneven shape is formed.

  Hereinafter, the metal mold base material, the heat insulating layer, the heat conductive layer, and the metal film, which form the basic structure of the mold of the present invention, as well as the layers such as the metallic layer and the bonding layer will be described.

Metal mold base metal The metal mold base material only needs to be made of metal, and may be the same material as that used in known or commercially available molds. For example, metal (metal simple substance) such as iron, aluminum, copper,
Examples of the alloy include carbon steel, stainless steel, copper alloy, and titanium alloy. Further, the metal mold base material may be either a melted material or a sintered body. In particular, in the present invention, it is preferable to use an iron-based metal as a metal mold base material in order to achieve both hardness and workability. That is, it is preferable to use at least one iron-based metal of metallic iron and iron alloy. It does not specifically limit as an iron alloy, For example, carbon steel, stainless steel (SUS), chromium molybdenum steel etc. can be used suitably.

  Further, the molding surface side of the metal mold base material may be either a flat surface or a curved surface, and may be a reversing mold of a fine shape to be imparted to the final molded body. It can comprise suitably according to the shape of the molded object to perform. For example, in particular, when the mold requires a deep recess (groove), an inverted mold having a shape to be transferred to the molding surface in advance or a similar shape (concave) is formed on the molding surface side of the metal mold base material. May be.

Heat-insulating layer The heat-insulating layer in the mold of the present invention is filled with 1) a porous film in which ferrite crystal particles are formed in a three-dimensional network, and 2) at least part of voids in the porous film. Containing solid material. As described above, in the mold of the present invention, the heat insulating layer has a structure in which voids of the porous structure (porous and crystalline ferrite film (that is, spinel iron-based oxide)) are filled with a solid material. When using the mold of the present invention, high heat insulating properties can be obtained, and at the same time, deformation of the mold surface due to deformation of the heat insulating layer can be suppressed or prevented at high pressure during resin molding. More specifically, with respect to heat insulation, since the heat insulation layer is formed between the metal mold base material and the metal film constituting the molding surface, the heat of the molten resin molding material It is possible to effectively suppress or prevent a phenomenon in which energy is rapidly taken away by a metal mold base material. In terms of strength, in a heat insulating mold that employs a conventional porous film as a heat insulating layer, the skeletal portion constituting the porous layer collapses due to the high-pressure molten resin, which in turn causes deformation due to the depression of the porous layer. The heat insulation layer of the present invention is composed of a composite material of a specific ferrite porous membrane and a solid material filling the fine voids, so that deformation and the like that occur in a conventional heat insulation mold are effectively prevented. be able to.

  In the mold of the present invention, as the heat insulating layer, for example, as in the heat insulating layer 64 shown in FIG. 19, a porous film 64a in which ferrite crystal particles are connected in a three-dimensional network and voids in the porous film A structure composed of the solid material 64b filled in at least a part of the (pores) can be suitably employed.

  The porous film is formed by forming ferrite crystal particles (crystalline ferrite particles) in a three-dimensional network. In the present invention, by adopting ferrite among metal oxides in particular, higher heat insulation can be obtained, and high adhesion to a metal mold or a metal layer that is the base can be exhibited. The ferrite crystal particles may be twins or may be a series of crystals. The ferrite crystal particles constituting the porous film preferably have a spinel crystal structure as will be described later.

  The form of the porous film is not particularly limited as long as ferrite crystal particles are formed in a three-dimensional network. For example, a porous film may be formed from a three-dimensional network structure in which a plurality of polyhedral crystal particles that are not rounded and have one or more corners are connected. In this case, the voids in the porous film are open pores and communication holes. Thereby, the solid material can be efficiently filled in the entire porous membrane by injecting (impregnating) the liquid material of the solid material into the voids.

In the present invention, the ferrite has the following general formula A _x Fe _3-x O ₄ (where A represents at least one metal element that can be substituted for the Fe site constituting the spinel-type iron oxide crystal, and x represents 0 ≦ x <1 is satisfied.)
It is preferable that it is a compound which has a spinel type crystal structure shown by these.

Since x is 0 ≦ x <1, the case of x = 0, that is, the case of iron ferrite (that is, spinel-type iron oxide Fe ₃ O ₄ ) is included, and a part of the Fe site is replaced with other parts. The composition may be substituted with a metal element.

As described above, A is not limited as long as it is at least one metal element that can be substituted for the Fe site constituting the spinel-type iron oxide crystal, but Ca, Zn, Mn, Al, Cr, Li, and Mg are not particularly limited. It is desirable to be at least one of these. Therefore, in the present invention, a composition in which the A component is at least one of Ca, Zn, Mn, Al, Cr, Li, and Mg may be used. Such a composition itself may be any known one, for example, Ca _0.5 Fe _2.5 O ₄ , ZnFe ₂ O ₄ , MnFe ₂ O ₄ , AlFe ₂ O ₄ , CrFe ₂ O ₄ , Li can be mentioned _0.5 Fe _2.5 O _4, MgFe least one such ₂ O _4.

  The porosity of the porous membrane (porosity in the state before being filled with the solid material) is not limited, but is usually about 5 to 75%, particularly 40 to 60% from the viewpoint that higher heat insulation performance can be achieved. It is preferable to be within the range. The porosity can be controlled by synthesis conditions such as synthesis temperature and raw material concentration. The method for measuring the porosity in the present invention is based on the method shown in Example 1 described later.

  In particular, the porous membrane is formed by hydrothermal synthesis reaction of 1) the surface of a metal mold base material or 2) the surface of a metal layer previously formed on the surface of the mold base material. It is desirable. The porous structure formed in this way is integrally formed with a metal mold base material or the like serving as the base, so that the heat insulating layer can be firmly bonded and fixed.

  Although it is not limited as a solid material filled in at least a part of the voids in the porous membrane, inorganic oxide glass is preferably used because it is particularly excellent in heat insulation and can be synthesized by a sol-gel method or the like. Can do. Depending on the additive composition, the glass generally has a thermal conductivity of about 1 W / m · K, and is a porous ferrite (spinel type iron ferrite: thermal conductivity 6.2 W / m · K). It is a substance with lower thermal conductivity.

  The kind (glass composition) of the inorganic oxide glass is not particularly limited, and can be appropriately selected from known glass compositions such as silica glass, soda lime glass, borosilicate glass, lead glass, and alkali-free glass. . Moreover, the glass composition which contains a metal component other than that in each of these glass is also included by this invention. Although it does not specifically limit as said metal component, At least 1 sort (s), such as aluminum, titanium, tin, zirconium, iron, chromium, zinc, manganese, can be employ | adopted suitably from a viewpoint of intensity | strength and manufacturing efficiency.

  Among these, in the present invention, from the viewpoint of strength and manufacturing process, for example, 1) borosilicate glass, 2) silica glass, and 3) at least one of aluminum, titanium, tin, zirconium, and iron is included in these compositions. At least one kind of inorganic oxide glass can be suitably used.

  In the mold of the present invention, part or all of the voids of the porous membrane are filled with a solid material, and the filling ratio depends on the porosity of the porous membrane, the desired heat insulating layer strength, etc. It can be set appropriately.

  The thickness of the heat insulating layer may be appropriately set according to the type of molding material to be used, desired heat insulating properties, etc., but can generally be set within a range of 15 μm or more. In particular, it is preferably 15 to 1000 μm, and more preferably 30 to 150 μm. By setting the thickness of the heat insulating layer within the above range, it is possible to more effectively trace the base mold shape (base material surface) with a uniform film thickness.

Thermal Conductive Layer In the mold of the present invention, a thermal conductive layer having a thermal conductivity at 100 ° C. of 100 W / m · K or more is provided between the heat insulating layer and the metal film. By arranging the heat conductive layer between the heat insulating layer and the metal film, the heat conductivity in the horizontal direction is increased, the flow path in the direction of travel of the injected molten resin is heated, and the rapid temperature of the molten resin is increased. As a result of effectively suppressing the decrease, the molten resin can be uniformly filled in the unevenness of the entire molding surface, and a predetermined pattern shape can be more reliably transferred. At the same time, when high speed injection of the molten resin into the cavity (molding space), the thermal energy given locally from the molten resin to the surface of the metal film is instantaneously diffused in the heat conductive layer by the heat conductive layer. Deformation of the metal film surface due to local thermal expansion of the metal film due to a rapid temperature rise caused by thermal energy (thermal shock) applied to the surface of the metal film instantaneously at the time of molten resin injection Alternatively, it is possible to suppress or prevent deterioration of bonding adhesion with the heat insulating layer disposed thereunder.

  The material used as the heat conductive layer may be a material having a thermal conductivity of 100 W / m · K or more at 100 ° C., preferably a metal having a thermal conductivity of 100 W / m · K or more, more preferably a thermal conductivity of 150 W / m. A metal having m · K or more, most preferably a metal having a thermal conductivity of 300 W / m · K or more is employed. Examples of such metals include copper (physical property value of 395 W / m · K at 100 ° C.), aluminum (240 W / m · K), magnesium (154 W / m · K), zinc (112 W / m · K). In addition to K), an alloy containing these metals as a main component can be used. In particular, at least one of copper and a copper-based alloy containing copper as a main component can be suitably employed.

  Although the thickness of a heat conductive layer is not limited, Usually, it is about 3-50 micrometers, Preferably you may be 4-20 micrometers. By setting within this range, the effect of the present invention can be obtained more effectively.

  The formation method of a heat conductive layer is not limited, A well-known method is applicable. For example, plating methods such as electrolytic plating and electroless plating (liquid phase growth method); chemical vapor deposition methods such as thermal CVD, MOCVD, and RF plasma CVD; sputtering methods, ion plating methods, MBE methods, and vacuum deposition methods Various known thin film forming methods such as physical vapor deposition methods such as the above can be appropriately employed in combination of one or more.

Metallic layer Although the heat insulating layer in the metal mold of the present invention may be formed directly on the surface of the metal mold base material, in order to further improve the bondability between the heat insulating layer and the metal mold, FIG. As shown in FIG. 5, a metal layer 63 (heat insulation film foundation layer) may be interposed as a foundation layer of the heat insulation layer 64 as necessary. In this case, it is desirable that the metallic layer be formed between the surface of the metal mold base material and the heat insulating layer in contact with both.

  The composition of the metallic layer is not particularly limited as long as the above object can be achieved, but it preferably contains a metal element constituting the composition of the heat insulating layer, and more preferably iron. That is, the skeletal component of the heat insulating layer of the present invention is a porous ferrite film (porous film), which can be suitably formed by, for example, a hydrothermal synthesis reaction, so that while dissolving the surface of the underlying metallic layer, Growth nuclei of the porous ferrite film can be formed on the surface of the metallic layer, and a homogeneous and strong heat insulating layer can be formed using the nuclei as a nucleus. Therefore, since the porous ferrite film is a film containing iron as a main component, it is desirable that the porous ferrite film be a metallic layer made of metallic iron.

Bonding layer In the present invention, a bonding layer can be formed as necessary in order to further improve the adhesion and bonding properties between the heat insulating layer and the heat conductive layer. For example, as shown in FIG. 18, a bonding layer 65 can be interposed between the heat insulating layer 64 and the heat conductive layer 66. Thereby, especially in the formation process of the metal film by a plating method, the heat insulation metal mold | die with which the heat insulation layer and the metal film were joined firmly can be provided.

  The bonding layer may be composed of a single layer or may be composed of multiple layers. The bonding layer may be formed directly on the surface of the heat insulating layer as a single layer. Further, as a two-layer structure including the first bonding layer and the second bonding layer, the second bonding layer may be laminated with the first bonding layer interposed for the purpose of bonding the heat conductive layer to the heat insulating film more firmly. . The bonding layer is preferably formed in contact with both of the heat insulating layer and the heat conductive layer formed on the metal mold base material.

  Usually, the bonding layer is preferably formed on the heat insulating layer. For example, in the case of using a) a vacuum apparatus, a metal film that is easily oxidized to form a strong oxide film on the surface in order to firmly bond to the surface of the heat insulating layer that is an oxide, and further It may be a thin film made of a metal in which another metal film is firmly adhered to the surface, or b) a catalyst metal necessary for directly forming a metal film by electroless plating on the heat insulating layer on the heat insulating layer ( It may be a thin film made of a catalytic metal for the purpose of supporting palladium or the like.

  More specifically, the bonding layer in the case of a) can be suitably formed by sputtering using a sputtering apparatus as the vacuum apparatus. Thus, the bonding layer is formed on the surface uneven portion on the heat insulating layer. The material of the bonding layer is particularly preferably a metal that is easily oxidized to form a strong oxide film on the surface. For example, at least one of titanium (Ti), tantalum (Ta), chromium (Cr), molybdenum (Mo), tungsten (W), and the like is preferable. The thickness of the bonding layer may be appropriately set according to the type of the metal element constituting the bonding layer, the unevenness of the surface of the heat insulating layer, etc., but is usually within a range of about 0.02 to 0.8 μm. .

  In this way, by continuously forming the metal film of the heat conduction layer on the metal film of the bonding layer by the same sputtering method, the metal (bonding film surface) -metal (heat conduction film lower surface) Bonds can be formed.

  In the case of a multilayer, a second bonding layer made of a continuous metal film may be formed on the bonding layer (first bonding layer) for the purpose of further increasing the bonding strength with the heat conductive layer. In this case, the second bonding layer is preferably at least one of iron and an iron alloy. What is necessary is just to set suitably according to the kind of metal element which comprises it, the thickness of a heat insulation layer, surface unevenness | corrugation (surface roughness), etc., However, Usually, it should just be in the range of about 1-6 micrometers.

Metal film The metal film should just be comprised from the metal, and may be the same as the material employ | adopted as the molding surface of a well-known or commercially available metal mold | die. Examples thereof include metals such as iron, nickel, copper and chromium, alloys such as nickel phosphorus alloys, nickel boron, nickel tungsten phosphorus alloys and nickel copper phosphorus alloys.

  Moreover, the structure of the metal film may be a single layer or a multilayer. For example, in order to further improve the adhesion (bondability) between the heat insulating layer and the metal film, the metal film has a two-layer structure including a first metal film and a second metal film, and the metal film bonding layer and the second metal film are A first metal film can be interposed as an adhesive layer (underlayer) between these layers. More specifically, a configuration comprising a metal plating film (first metal film) formed on the metal film bonding layer and a microfabricated metal film (second metal film) formed on the metal plating film is adopted. can do. In this case, regardless of the material constituting the metal film bonding layer, a finely processed metal film (second metal film) whose surface is finely processed (uneven surface) is formed as a layer constituting the molding surface with good adhesion. can do.

  As a method for forming the metal film, for example, a known method can be employed according to the metal species used as the metal film, the composition of the underlying layer, and the like. For example, plating methods such as electrolytic plating and electroless plating (liquid phase growth method); chemical vapor deposition methods such as thermal CVD, MOCVD, and RF plasma CVD; sputtering methods, ion plating methods, MBE methods, and vacuum deposition methods Various known thin film forming methods such as physical vapor deposition methods such as the above can be appropriately employed in combination of one or more.

  When the metal film has a multilayer structure, the formation method of each layer may be different, and any of the above-described thin film formation methods can be used in appropriate combination. For example, when the first metal film as an adhesive layer (underlying layer) and the second metal film formed thereon are used, each layer can be formed by the following method. For example, a metal plating film (first metal film) formed by an electrolytic plating method such as a strike plating film is formed on the metal film bonding layer, and a thick microfabricated metal film is plated on the metal plating film. It can be formed by the method. By taking such a configuration, it is possible to further increase the bonding strength between the metal film bonding layer and the metal film.

  The method for producing the molding surface is not limited, and may be the same as in the case of a known heat insulating mold. For example, a molding surface having a predetermined shape (uneven shape) can be formed by subjecting the metal film surface to mechanical processing such as cutting.

  The thickness of the metal film in the mold of the present invention (in the case of a multilayer structure, the total thickness of each layer) is not particularly limited, but is usually about 20 to 300 μm, and preferably 50 to 150 μm. What is necessary is just to set the thickness of each layer in the case of a multilayer structure suitably according to the number of layers, the material of each layer, etc.

Use of heat insulating mold The heat insulating mold of the present invention can be used in the same manner as known or commercially available molds. Moreover, the molding conditions and the like when molding using a mold can be carried out according to a known method.

  When molding using the mold of the present invention, the mold of the present invention can be used as a part or all of the molding space of the mold. For example, when molding by injection molding into a cavity formed by two molds, a fixed mold and a movable mold, the mold of the present invention can be adopted as at least one of the fixed mold and the movable mold. Moreover, it is possible to carry out molding using the mold of the present invention simply by replacing a part or all of a commercially available mold (molding apparatus) with the mold of the present invention.

  For example, when the resin molded product 91 having two light guide plates as shown in FIG. 16 is injection-molded, in a mold composed of a fixed mold and a movable mold, the mold of the present invention is used as a movable mold. A schematic diagram is shown in FIG. A resin molded product 91 in FIG. 16 is molded in a state where two light guide plates 92 and 92 are connected via a runner portion 94. In this way, two light guide plates are manufactured simultaneously. In FIG. 17, a mold composed of a fixed mold 101 and a movable mold 102 is used as a molding apparatus. After the resin 108 is injected and introduced into the cavity 107 (molding space) between the fixed mold, the movable mold, and the frame body portion 103, the resin 108 is cooled while maintaining the pressure as shown in the figure. . Thereafter, the movable mold 102 is lowered, the frame body portion 103 is moved in the horizontal direction, the mold is opened, and the mold is released, and then the desired resin molded product 91 is collected. In this case, the mold of the present invention is adopted as the movable mold 102, and a predetermined shape is given to the molding surface of the mold of the present invention. The molten resin was injected by the heat insulating layer of the mold of the present invention, and even when the molten resin was introduced into the molding space of the mold, the thermal energy of the molten resin was applied to the molding surface without being rapidly taken away by the mold. As a result of the molten resin all over the unevenness or the groove, the pattern shape is faithfully transferred to the resin molded product. Thereby, a molded product in which a fine shape is accurately reproduced can be obtained.

Molding material In the heat-insulating mold of the present invention, the material (molding material) used therein is not limited, but particularly molding of a composition containing a resin component (particularly a resin composition containing a resin component as a main component) (injection molding, etc.) It is suitable for.

  For example, it can be suitably used for resin molding. Resin components (especially synthetic resins) include polyethylene, polypropylene, polystyrene, polyvinyl chloride, polymethyl methacrylate, polyamide, polycarbonate, ABS resin, polyethylene terephthalate, polytetrafluoroethylene, and other polycycloolefins. Etc. can be mentioned as a preferable example. As a component other than the resin component, for example, a filler, a colorant, an ultraviolet absorber, an antistatic agent, a flame retardant and the like may be included in the composition as necessary.

2. Manufacturing method of heat insulation mold Although this invention metal mold | die can be manufactured by forming and laminating | stacking each above layers, it can manufacture suitably by the following method especially.

That is,
(1) A step of forming a porous film in which ferrite crystal particles are formed in a three-dimensional network form on the surface of the metal mold base material on the molding surface side (porous film forming step);
(2) A step of forming a heat insulating layer in which at least a part of the pores in the porous film is filled with the solid material by filling the solid material into at least a part of the pores in the porous film (solid material Filling process),
(3) forming a metal film bonding layer on the surface of the heat insulating layer by physical vapor deposition (metal film bonding layer forming process);
(4) A step of forming a heat conductive layer having a thermal conductivity of 100 W / m · K or more on the surface of the metal film bonding layer by a physical vapor deposition method (heat conductive layer forming step),
(5) A process of forming a metal film on the surface of the heat conductive layer by a plating method (metal film forming process) and (6) Forming a transfer-shaped surface for resin molding by machining the surface of the metal film Process (molding surface forming process)
The mold according to the present invention can be preferably manufactured by a method for manufacturing a heat-insulating mold characterized in that

Porous film forming step In the porous film forming step, a porous film in which ferrite crystal particles are formed in a three-dimensional network is formed on the surface of the metal mold base material on the molding surface side.

  In the present invention, as the porous film forming step, 1) the surface of the metal mold base material or 2) the surface of the metal layer previously formed on the surface of the mold base material is an aqueous solution containing a metal component or A method including a step of producing a metal oxide by reacting with an aqueous dispersion (treatment liquid) can be suitably employed.

  As the treatment liquid, an aqueous solution or an aqueous dispersion containing a metal component can be suitably used. As the metal component, a component that can form a ferrite crystal may be employed. In particular, (1) Fe alone or (2) at least one of Ca, Zn, Mn, Al, Cr, Li, and Mg and Fe. A combination is desirable. For the preparation of the aqueous solution or aqueous dispersion, for example, a compound serving as a supply source of a metal component can be used. For example, a metal salt, a metal oxide, a metal hydroxide, or the like can be used. For these, any of water-soluble (water-soluble) or poorly water-soluble metal compounds can be used, but in the present invention, a water-soluble metal compound can be more suitably used.

  In addition, the concentration of the metal component in the treatment liquid is not limited and can be appropriately set according to the type of metal component to be used, reaction conditions, etc., but is usually 0.03 to 0.35 g / mL. Is preferred.

  The reaction can be carried out according to a known wet reaction method. For example, any of a method of immersing in a treatment liquid, a method of applying the treatment liquid by spraying, and the like can be employed. In particular, in the present invention, it is preferable to carry out the hydrothermal synthesis reaction using the treatment liquid. The hydrothermal synthesis reaction condition itself may be a known method, but it is particularly preferable to carry out the following method. That is, as the hydrothermal synthesis reaction, 1) a metal mold base material surface or 2) a metal layer surface previously formed on the mold base material is a treatment liquid in which a metal salt, alkali and water are mixed. It is preferable to employ a method including a step of heat-treating in an environment having a saturated water vapor pressure of 100 to 200 ° C. or higher in a state where it is in contact with.

  In the hydrothermal synthesis reaction described above, it is preferable to use a treatment liquid obtained by mixing a metal salt, an alkali and water. The mixing method is not particularly limited, and the blending order is not limited.

  As the metal salt, at least one of an inorganic acid salt and an organic acid salt can be used. As the inorganic acid salt, for example, sulfate, carbonate, chloride and the like can be used. Moreover, acetate, an oxalate, etc. can be used as organic acid salt.

  The alkali is not particularly limited, and for example, at least one of sodium hydroxide, potassium hydroxide, ammonia and the like can be used.

  In the treatment liquid, the metal salt or alkali may be dissolved in water or may be partially dissolved. Moreover, the thing (suspension (water dispersion)) disperse | distributed without melt | dissolving a metal salt or an alkali may be sufficient. In this case, the content of the metal salt in the treatment liquid is generally preferably 0.03 to 0.35 g / mL, although it depends on the type of the metal salt used. Further, the alkali is preferably 0.05 to 0.18 g / mL, although it depends on the type of alkali used.

  Moreover, in this invention, reaction with a process liquid can also be implemented in presence of a reducing agent. By using a reducing agent, it is possible to form a more excellent heat insulating film by suppressing or preventing the production of trivalent iron ions in the reaction system. Therefore, the reducing agent is not limited as long as it can suppress or prevent the production of trivalent iron ions, and can be appropriately selected from known reducing agents. For example, compounds known as antioxidants such as ascorbic acid and hydroquinones can be suitably used. In the present invention, it is preferable to contain a reducing agent in the treatment liquid (particularly, the reducing agent is dissolved in the treatment liquid).

  In the present invention, the treatment liquid is brought into contact with 1) the surface of a metal mold base material or 2) the surface of a metal layer previously formed on the mold base material. That is, the treatment liquid is applied to the region where the heat insulating layer is to be formed. The method of providing is not particularly limited, and can be performed according to a known method such as dipping or coating. As a usage amount of the treatment liquid, it is preferable to give a sufficient amount for forming a predetermined heat insulating layer. Therefore, in this invention, the method of immersing the site | part which should form a heat insulation layer in a process liquid can be employ | adopted suitably, for example.

  The conditions for reacting with the treatment liquid are not particularly limited as long as ferrite can be generated. In particular, when a hydrothermal synthesis reaction is performed as a reaction with the treatment liquid, the temperature and pressure conditions are preferably heat treatment in an environment of a saturated water vapor pressure of 100 to 200 ° C. (particularly 110 to 200 ° C.). . A predetermined heat insulation layer can be suitably formed by heat-treating under such temperature and pressure. Such temperature and pressure conditions can be set using a known device such as an autoclave device (sealed system).

  Moreover, the time (reaction time of hydrothermal synthesis reaction) made to react with a process liquid can be suitably adjusted according to the thickness etc. of a desired heat insulation layer. That is, the reaction may be continued until the heat insulating film having the preferable thickness is formed. In order to obtain a heat insulating film having a uniform thickness with a desired thickness, the reaction is usually performed for 2 to 12 hours in the case of hydrothermal synthesis reaction. What is necessary is just to form by the method of repeating reaction within the range several times.

In the production method of the present invention, the above-described 1. Therefore, it is preferable to use an iron-based metal as the metal base material or the metallic layer. By reacting the iron-based metal surface with the treatment liquid (particularly, hydrothermal synthesis reaction), a ferrite layer as a heat insulating layer can be suitably formed. For example, when generating iron ferrite (when x = 0 described above), according to the hydrothermal synthesis reaction of the present invention, ferrite can be generated from iron through the following steps 1) to 2).
1) Fe ²⁺ + OH ⁻ → Fe (OH) ₂ , 2) Fe (OH) ₂ → Fe ₃ O ₄

As an embodiment of the manufacturing method of the present invention, there are various variations depending on the layer structure, and these are all included in the present invention. For example, in the case of hydrothermal synthesis reaction (or normal wet reaction): a) Production of porous ferrite film by hydrothermal synthesis reaction (wet reaction) on the metal mold base material and the pores of the porous film Including a step of forming a heat insulating film by filling with a solid material, a step of forming a seed layer as a bonding layer on the surface of the heat insulating film by a sputtering method, and a step of forming a metal film by plating on the seed layer. Method b) Step of forming a heat insulating film underlayer which is a metallic layer on the metal mold base material by plating or sputtering, hydrothermal synthesis reaction (wet reaction) and solid on the surface of the heat insulating film underlayer A step of forming a heat insulating film by filling the material, a step of forming a seed layer on the surface of the heat insulating film by a sputtering method, and a metal film by a plating method in contact with the seed layer The method comprising the degree,
c) A step of forming a thermal insulation film underlayer by plating or sputtering on the upper layer of the metal mold base material, and a thermal insulation reaction (wet reaction) and solid material filling on the thermal insulation film underlayer. Forming a bonding layer in contact with the upper surface of the heat insulating layer by sputtering, and further forming a first metal film (underlying adhesion film) thereon by electroplating or sputtering; and A method comprising a step of forming a second metal film in contact with the upper surface by a plating method;
These are all included in the production method of the present invention.

In the solid material filling step, in the solid material filling step, at least a part of the pores in the porous film is filled with the solid material, so that at least a part of the pores in the porous film is filled with the solid material. Form.

  As the solid material filled in the voids of the porous membrane, the various glasses described above can be applied. In this case, the method of filling the solid material is not particularly limited as long as the solid material can be filled in the pores. For example, the step of injecting the liquid material of the solid material into the voids of the porous film and the solid material from the injected liquid material By the method including the step of generating the structure, the structure in which the solid material is filled in the voids (pores) of the porous film can be formed.

  In particular, in the present invention, a solid material can be suitably filled by using a sol-gel method. As a starting material in this case, a material used in a known sol-gel method can be adopted, and a liquid material containing a target oxide precursor (compound) and a solvent can be adopted.

  As said precursor, 1 type (s) or 2 or more types, such as an organometallic compound or an organosilicon compound, a metal salt (however, except an organometallic compound and an organosilicon compound), can be used conveniently, for example.

  Examples of the organometallic compound include metal alkoxides such as zirconium (IV) propoxide and zirconium (IV) butoxide; metal organic acid salts such as zirconium acetate and zinc acetate.

  Examples of organosilicon compounds include alkoxysilane compounds such as methyl silicate (tetramethoxysilane) and ethyl silicate (tetraethoxysilane); organopolysiloxane compounds having a hydroxyl group at the end such as dihydropolydimethylsiloxane; Also, organopolysiloxane having an alkoxysilane functional group can be used.

  Examples of the metal salt include nitrates and chlorides of various metals. In the present invention, a metal salt of an organic acid is included in the organometallic compound.

  As the solvent, (1) water or (2) a mixed solution (mixed solution) of water and a water-soluble organic solvent can be suitably used. The water-soluble organic solvent is not limited, and alcohols such as methanol, ethanol and isopropanol can be suitably used.

  Moreover, a catalyst can also be used for a liquid raw material as needed. For example, as the titanium-based catalyst, one or more of tetraisopropyl orthotitanate, diisopropoxy titanium bis (acetylacetonate), titanium tetra (acetylacetonate), and the like can be used. As the organic tin-based catalyst, one or more of dibutyltin diacetate, tin 2-ethylhexanoate, bis (lauroxydibutyltin) oxide and the like can be used. As the compound containing boron ions, one or more of trimethyl borate and triethyl borate can be used. As a compound containing a halogen ion, 1 type (s) or 2 or more types, such as hydrochloric acid and acidic ammonium fluoride, can be used.

  Specific methods include, for example, a) a hydrolyzable liquid organometallic compound, b) a titanium-based catalyst, an organotin-based catalyst, a compound containing boron ions, a compound containing halogen ions, and c) water. The liquid raw material contained is applied to or impregnated into the porous film, and the reaction proceeds in the voids. By this reaction, the polycondensation reaction by hydrolysis under a catalyst is promoted, and the reaction product filled in the voids is solidified.

  In this case, generally, a liquid organometallic compound that causes hydrolysis, for example, an organopolysiloxane having an alkoxysilane functional group, is hydrolyzed with a titanium-based catalyst such as a titanium chelate compound or an organotin-based catalyst in the presence of moisture (or moisture). Decomposition is accelerated, viscosity increases, and it can be solidified. Further, by adding boron ions and halogen ions to a mixed liquid composed of metal alkoxide, which is the same kind of liquid material, water and alcohol, hydrolysis can be similarly promoted and solidified. These solidified substances are considered to be compounds in which an M—O bond containing an organic component (M represents Si or a metal) is polymerized. It burns down and changes to a hard solid material whose main component is composed of an inorganic oxide glass material (for example, borosilicate glass or the like).

  Subsequently, by heat-treating the reaction product, the reaction product is changed into a hard solid material. The heat treatment temperature varies depending on the type of the solid material and the like, but is particularly preferably a temperature at which the metal mold main body is not softened by annealing, and is usually more preferably about 200 to 300 ° C. Although the heat treatment atmosphere is not limited, a predetermined oxide glass can be generated by oxidatively decomposing an organic component from the reaction product by performing the heat treatment in an oxidizing atmosphere (or in the air).

  The method of injecting the liquid raw material into the porous film is not limited, and a known method can be used. In particular, in the present invention, it is preferable to suitably employ a method including a step of pressurizing the porous membrane in a state of being immersed in the liquid raw material under reduced pressure and a step of effectively injecting the liquid raw material into the voids of the porous membrane. it can. More specifically, a porous membrane is placed in a sealed container, the liquid raw material is introduced in a state where the inside of the sealed container is sufficiently decompressed, and the porous membrane is immersed in the liquid raw material in the sealed empty container. By the method of flowing air (air) and returning from reduced pressure to atmospheric pressure, it is possible to fill the fine voids of the porous membrane with the liquid raw material.

Bonding layer forming step In the bonding forming step, a bonding layer is formed on the surface of the heat insulating layer by physical vapor deposition. The material of the metal film bonding layer is the same as described in 1. As explained in.

  The physical vapor deposition method (PVD method) is not limited, and examples thereof include a sputtering method, an ion plating method, an MBE method, a vacuum deposition method, and the like, and a sputtering method is particularly preferable. The sputtering method can be performed using a known or commercially available sputtering apparatus. In particular, in the present invention, a DC magnetron sputtering apparatus or an RF magnetron sputtering apparatus is preferable, and the sputtering conditions are not limited. Especially, argon is used as an inert gas, and the degree of vacuum is 0.2 to 2.0 Pa. It is desirable to employ the condition that the substrate heating temperature is 50 to 300 ° C.

  The bonding layer may be composed of a single layer or may be composed of multiple layers. In the case of a single layer, it may be a seed layer having a catalytic action for electroless plating. Further, a metal film functioning as a base bonding film for the metal sputtered film may be used. Such a metal film is a metal film for the purpose of firmly adhering to the heat insulating layer made of oxide, and the construction method is a vacuum film-forming method that facilitates the subsequent lamination of the metal material of the heat conductive layer. preferable. When the bonding layer is multi-layered, a two-layer structure in which a second bonding layer made of a metal having conductivity that promotes plating formation of the heat conductive layer on the bonding layer (first bonding layer) can be adopted. .

  That is, the step of forming the bonding layer includes a step of forming a first bonding layer as a bonding film with the heat insulating layer by a sputtering method and a step of forming a second bonding layer as a conductive metal film by a sputtering method. It may be a composite process.

  As the bonding layer, a metal that is easily oxidized to form a strong oxide film on the surface is particularly preferable. For example, titanium (Ti), tantalum (Ta), chromium (Cr), molybdenum (Mo), tungsten (W) or the like or an alloy thereof is preferable. The thickness of the bonding layer, which is the bonding layer, may be appropriately set according to the type of metal element constituting the bonding layer, the thickness of the heat insulating layer, the surface unevenness, etc., but the effect of the present invention can be achieved more effectively. From the standpoint of doing, it is usually set to about 0.02 to 0.8 μm.

  In addition, the material of the second bonding layer in the case of forming the second bonding layer is not particularly limited as long as it is made of a highly conductive metal. In particular, a metal or the like that can easily form a dense film by a sputtering method and that can easily form a strong metal plating film by an electrolytic plating method can be suitably used. In particular, as the composition of the conductive metal film, for example, an iron metal alone or an alloy such as an iron alloy can be suitably employed. The thickness of the second bonding layer may be appropriately set according to the type of metal element constituting the second bonding layer, the unevenness of the surface of the heat insulating layer, etc., but is usually about 1 to 6 μm. .

Thermal conductive layer forming step In the thermal conductive layer forming step, a thermal conductive layer having a thermal conductivity of 100 W / m · K or more is formed on the surface of the bonding layer by physical vapor deposition.

  As the heat conductive layer having a thermal conductivity of 100 W / m · K or more, the metals exemplified above can be suitably used. A heat conductive layer made of such a metal is also preferable in that a physical vapor deposition method can be applied.

  The physical vapor deposition method (PVD method) is not limited, and examples thereof include a sputtering method, an ion plating method, an MBE method, a vacuum deposition method, and the like, and a sputtering method is particularly preferable. The sputtering method can be performed using a known or commercially available sputtering apparatus. In particular, in the present invention, a DC magnetron sputtering apparatus or an RF magnetron sputtering apparatus is preferable, and the sputtering conditions are not limited. Especially, argon is used as an inert gas, and the degree of vacuum is 0.2 to 2.0 Pa. It is desirable to employ the condition that the substrate heating temperature is 50 to 300 ° C.

  Further, the configuration of the heat conductive layer may be a single layer or a multilayer. In the case of a multilayer, the second heat conductive layer made of a thick metal film can be formed on the single layer film by a wet method such as an electrolytic plating method having a high film formation rate. Moreover, in the case of a multilayer, the multilayer which is the same material mutually may be sufficient, and the multilayer which consists of a mutually different material may be sufficient. In this case, it is particularly preferable to form the second heat conductive layer using a material such as copper. In addition, although the thickness in that case changes with sizes and shapes of a metal mold | die, the thickness of a heat insulation layer, etc., it is usually preferable to set it as about 5-50 micrometers from the viewpoint of achieving the effect of this invention more effectively. .

Metal film forming step In the metal film forming step, a metal film is formed on the surface of the heat conductive layer by a plating method. In this case, the step of forming a metal film on the surface of the conductive metal film using a plating method can be carried out according to a known method, but is preferably carried out by the following method. That is, when the metal film bonding layer is a seed layer made of a catalytic metal film, it is desirable to form a metal film by an electroless plating method after forming the base electroless plating film. Further, a method of forming a metal film by an electroless plating method after forming a base electroplating film using a conductive metal film forming a metal film bonding layer as an electrode is desirable. Here, the Ni strike plating method is particularly desirable as a method for forming the base electroplating film. Further, as the metal film formed on the surface by the electroless plating method, a nickel phosphorus alloy plating film is particularly preferable. The conditions of the strike plating method or the electroless plating method may follow a known method.

Molding surface forming step In the molding surface forming step, the surface of the metal film is machined to form a transfer shape surface for resin molding. The machining may be performed according to a known method. For example, a desired shape (uneven shape) can be imparted to the surface of the metal film using a known or commercially available precision cutting machine or the like.

  The features of the present invention will be described more specifically with reference to examples. However, the scope of the present invention is not limited to the examples.

Example 1
In FIG. 1, sectional drawing which shows the structure of the heat insulation metal mold | die 1 of this invention of the present Example 1 is shown. The heat insulating mold 1 is a mold used for molding a resin part having a precise finely processed shape such as a light guide plate shown in FIG. 16, and is a rectangular parallelepiped having a longitudinal direction of 100 mm, a lateral direction of 62 mm, and a height of 15 mm. Shape.

  Stainless steel having high hardness was used as the material of the metal mold base material 2 constituting the mold. The metal mold base material 2 has a rectangular parallelepiped shape having a longitudinal direction of 100 mm, a lateral direction of 62 mm, and a height of 14.5 mm. A stepped grinding process is performed to remove the outer peripheral portion having a width of 0.3 mm and a height of 2 mm from the upper surface, thereby forming a convex shape.

  A metallic layer 3 (thickness 3 μm) made of an iron film is disposed on the convex surface of the metal mold base 2 on the molding surface side, and a crystalline iron ferrite film (that is, a thickness of 3 μm) is formed thereon. A heat insulating layer 4 (thickness: 200 μm) filled with a solid material made of inorganic oxide glass mainly composed of silicon, boron and tin is disposed in a void of a porous film made of spinel iron oxide), and further A bonding layer 5 made of titanium is disposed on the surface, and a heat conductive layer 6 is formed thereon. The heat conductive layer 6 is composed of a total of 20 μm copper layers, a first heat conductive layer 6 a made of copper having a thickness of 2 μm and a second heat conductive layer 6 b made of copper having a thickness of 18 μm. Further, a first metal film 7a (nickel) having a thickness of 2 μm is coated on the heat conductive layer. Further, a second metal film 7b (amorphous nickel phosphorus alloy) for precision machining having a thickness of 200 μm is formed by electroless nickel plating. The molding surface side of the metal film 7 is a precision machined surface 7s in which a fine pattern for resin molding having a maximum depth of 25 μm is formed by precision machining.

  According to the above configuration, the voids in the conventional porous ferrite film effective as the heat insulating layer of the heat insulating mold are mainly composed of silicate inorganic glass having lower thermal conductivity than ordinary ceramics such as ferrite. Because it has a layer structure filled with solid material, it retains the low thermal conductivity as a ceramic material as in the past, but the weakness of the conventional porous ferrite thermal insulation film, that is, the mold forming surface by high-pressure molding of resin products It is possible to effectively suppress or prevent the dent deformation. As a result, good resin molding of a thin molded product having a fine pattern that requires high-pressure molding can be performed over a longer period of time.

  In FIG. 2, the example of a manufacturing process of the heat insulation metal mold | die 1 of this invention is shown. Hereinafter, each step will be described in accordance with the steps shown in FIG.

  On the surface of the metal mold base material 2 made of stainless steel having the above dimensions, a metallic layer 3 that is an iron film having a thickness of 3 μm was formed by an electroplating method using an iron sulfate plating bath (FIG. 2 ( 1)).

  A heat insulating layer 4 (thickness: 200 μm) formed by filling the voids of the porous ferrite film with an amorphous inorganic solid compound was formed on the metallic film 3 (FIG. 2 (2)). For the heat insulating layer 4, first, the voids of the porous ferrite film having a thickness of 250 μm were filled with a solid material, and then processed by precision mechanical polishing so that a smooth surface was obtained up to a thickness of 200 μm, thereby producing the heat insulating layer 4. .

  The filling of the solid material was performed through the four steps shown in FIG. That is, (1) a step of forming a porous ferrite film on the molding surface side of a metal mold base material, (2) a step of impregnating the voids of the porous ferrite film with a liquid material of a solid material, (3) Through a step of solidifying the liquid raw material by promoting solvent vaporization and hydrolysis reaction; and (4) a step of changing the solidified impregnated material into a predetermined solid material by heat treatment in an oxidizing atmosphere. Carried out.

First, a method for forming a porous ferrite film on the metallic layer 3 on the molding surface side of the metal mold base material will be described below. An aqueous solution in which 417 g of ferrous sulfate (FeSO ₄ · 7H ₂ O) was dissolved in 600 ml of water prepared by distillation in nitrogen gas was mixed with 600 ml of an aqueous solution of 216 g of sodium hydroxide (NaOH) to obtain a suspension. Prepared. The above suspension was placed in a cylindrical autoclave reaction vessel made of stainless steel having an internal volume of 2 liters, and the mold base material on which the metallic layer 3 was formed was immersed therein and held using a jig. The metallic mold base material 2 was previously masked with a sealing tape made of ethylene tetrafluoride except for the molding surface on which the metallic layer 3 was formed. The above operation was performed in a nitrogen gas atmosphere. The autoclave reaction vessel was externally heated to react at 130 ° C. for 20 hours. After the reaction time, the mold base material was taken out together with the jig, and washed sufficiently with water in order to separate from the powder compound of the reaction residue produced at the same time. The autoclave reaction vessel was also washed with water in order to remove the reaction residue produced in the same manner, and again the same amount of suspension was prepared as above, and the mold base material was attached together with the jig. The reaction process at 20 ° C. for 20 hours was repeated 8 times. In this way, a porous ferrite film having a thickness of 250 μm was formed.

  Next, prior to impregnating the voids of the porous ferrite film with the liquid material of the solid material, a liquid material of the solid material was prepared. As a liquid raw material, a mixed solution (125 ml of ethyl silicate, 10 ml of triethyl borate, 2 ml of tin ethylhexanoate, 3 ml of 0.1N-hydrochloric acid and 10 ml of ion-exchanged water at room temperature in the atmosphere (dissolved) A total of 150 ml) was used. This mixed solution gradually increases in viscosity with time and starts to solidify. Therefore, using the impregnation apparatus 11 shown in FIG. 4, this liquid raw material was immediately impregnated into the voids of the porous ferrite film formed on the molding surface side of the metal mold base material 2. The impregnation apparatus 11 shown in FIG. 4 includes two raw material containers 13 containing a liquid raw material 12 and an impregnation chamber 15 in which a sample 14 to be impregnated can be fixed. Are connected by a pipe 17 equipped with A vacuum exhaust pump 19 is connected to the impregnation chamber 15 via an open / close valve 18 so that the inside of the impregnation chamber 15 can be decompressed. A vacuum gauge 20 is attached to the impregnation chamber 15 so that the internal vacuum can be confirmed.

  A specific impregnation method is shown below. First, the impregnation chamber 15 of the impregnation apparatus 11 is opened, and a sample 14, which is a metal mold base material in which a porous ferrite film is formed on the molding surface side, is installed and fixed. Next, the valve 18 is opened, the vacuum exhaust pump 19 is operated, and the inside of the impregnation chamber 15 is decompressed. Next, the valve 18 is closed and the valve 16 is opened. At this time, the liquid raw material 12 stored in the raw material container 13 passes through the pipe 17 and is poured into the impregnation chamber 15 to which the sample 14 exposed to the reduced pressure atmosphere is fixed, and the internal pressure of the impregnation chamber 14 is atmospheric pressure. become. At this time, the liquid material that has flowed is impregnated into the voids that are open pores in the porous ferrite film formed in the sample 14. By the above operation, the liquid raw material was impregnated into the porous ferrite film.

  Subsequently, the impregnated liquid raw material was solidified by promoting solvent vaporization and hydrolysis reaction. That is, the metal mold base material on which the porous ferrite film impregnated with the liquid material is formed is wiped and removed from the excessive amount of the liquid material adhering to the surface, and then the humidity is 90% and the temperature is 70 ° C. The liquid raw material impregnated inside the polycrystalline ferrite film was solidified by putting it in a held constant temperature and humidity chamber and allowing it to stand for 10 hours, and promoting the hydrolysis reaction simultaneously with the removal of the solvent of the liquid raw material by vaporization. .

  Subsequently, the solidified impregnated material was changed to a solid material by heat treatment in an oxidizing atmosphere. The metallic mold base material provided with the porous ferrite film containing the impregnated material impregnated with the liquid raw material is solidified by performing a heat treatment for 3 hours at 300 ° C. in the atmosphere using an electric furnace. The organic component of the impregnated material was removed by vaporization or combustion, and the solidified impregnated material was changed to a solid material. Thereafter, a porous ferrite film (thickness: 250 μm) in which the voids were filled with a solid material was processed by precision mechanical polishing so that a smooth surface appeared to a thickness of 200 μm to form the heat insulating layer 4.

  Next, the bonding layer 5 and the first heat conduction layer are formed on the surface of the heat insulating film 4 using a dual high frequency magnetron sputtering apparatus having a planetary rotation mechanism and having a reverse sputtering function capable of installing two types of 6-inch diameter targets. 6a was formed (FIGS. 2 (3) and 2 (4)). That is, with respect to the metal mold base material formed up to the heat insulating film 4, the lower part of the metal mold base material 2 on which the heat insulating layer 4 is formed is masked except for the upper surface portion that is stepped. . Next, in the sputtering apparatus, the metal mold base material is attached to the substrate holder at an angle of 30 ° with respect to the target, and the substrate holder is rotated as a planet while the two-layer laminated sputtering film is formed as follows. Formed. That is, in a sputtering apparatus in which a metal titanium target and a metal copper target are previously installed, the metal mold base material on which the heat insulating layer 4 is formed is attached to the substrate holder and heated at 150 ° C. for 1 hour while being evacuated. After that, the surface of the metal mold base material on which a sputtered film was to be formed was reverse sputtered at a vacuum degree of 8 Pa using argon gas as a sputtering gas to perform surface cleaning. After that, while rotating the planet holder together with the planet, first, using a metal titanium target, sputtering was performed at a vacuum degree of 0.6 Pa and a sputtering input power of 2 kW for 2 minutes, thereby forming the bonding layer 5 with a thickness of 0.2 μm. Further, a dense first heat conductive layer 6a having a thickness of 2 μm was continuously formed by performing sputtering for 2 minutes with a sputtering input power of 2 kW at the same degree of vacuum using a metallic copper target.

  As for the film thicknesses of the bonding layer 5 and the first heat conductive layer 6a, a calibration curve of the relationship between the film thickness and the film formation time formed on the glass substrate attached to the substrate holder by changing the film formation time is prepared. Then, it was determined along the calibration curve from the sputter formation time. Here, utilizing the property that metal titanium easily forms a strong oxide film in the presence of oxygen, the titanium film of the bonding layer 5 reacts with the oxygen component of the composition of the heat insulating layer material made of the oxide immediately below. The titanium film at the interface is oxidized for the purpose of increasing the adhesion strength. Further, the copper film of the first heat conductive layer 6a thereon has a role of enhancing the thermal conductivity in the planar direction, and is bonded to the underlying titanium film to increase the adhesion strength, and at the same time has a high electrical conductivity. Therefore, the copper film of the second heat conductive layer 6b formed on the upper part by plating is also in close contact with each other to form a uniform film.

  Subsequently, the copper film of the 2nd heat conductive layer 6b was formed in the surface of the 1st heat conductive layer 6a (FIG. 2 (5)). That is, with respect to the metal mold base material formed up to the first heat conductive layer 6a, first, except for the upper surface portion, the other lower part is masked, and copper sulfate electroplating is performed to form a dense 18 μm thick. A second heat conductive layer 6b was formed. As described above, the heat conductive layer 6 (total thickness 20 μm) composed of the first heat conductive layer 6a and the second heat conductive layer 6b thereon was formed.

  Next, a first metal film 7a (nickel) having a thickness of 2 μm was coated by a nickel strike plating method. Further, a second metal film 7b (amorphous nickel phosphorus alloy) for precision machining having a thickness of 250 μm was formed by an electroless nickel plating method. Thus, the metal film 7 which consists of the 1st metal film 7a and the 2nd metal film 7b on it was formed, and it heat-processed at 200 degreeC for 3 hours (FIG. 2 (6)).

  Thereafter, using a precision cutting machine, the metal film 7 was first subjected to side processing so as to be smooth with the side surface of the metal mold base material 2. Subsequently, precision machining surface 7s was formed by precision grinding of the second metal film 7b to obtain a heat insulating mold 1 (FIG. 2 (7)).

  In addition, although the method by a plating method was illustrated in the present Example as a formation method of the metallic layer 3 which consists of an iron film formed on the surface of metal mold base materials 2, as a metal film, it is just under a heat insulation film. What is necessary is just the metal film which consists of a metal element which forms the heat insulation film | membrane. Further, the method for forming the metal film is not limited to the plating method described in this embodiment. For example, this iron film may be formed directly on the surface of the mold base material by a sputtering method.

Structural analysis of heat insulating layer Regarding the heat insulating layer 4 in the heat insulating mold 1 of the present invention, in order to confirm whether a film of a desired material is formed, the same material as the metal mold base material 2 (stainless steel) as a substrate A rectangular substrate (size: length 50 mm × width 20 mm × thickness 2.0 mm) was prepared, and a sample in which the heat insulating film A was formed on the substrate in the same manner as the method for forming the heat insulating layer 4 described above was prepared. Got ready. For comparison, a sample was also prepared in which a heat insulating film B made of a porous ferrite film, which is a material of a heat insulating layer of a conventional heat insulating mold, was formed on a substrate of the same material and the same size. The material of the heat insulating film A was evaluated in comparison with the heat insulating film B. A method for manufacturing the heat insulating film A and the heat insulating film B will be described below. First, two rectangular substrates were prepared, and a similar metal film was formed in the same manner as in the step of manufacturing the heat insulating mold 1 (FIG. 2 (1)). Thereafter, in the same manner as in FIG. 2 (2), suspensions having the same composition prepared from the same raw materials at the same mixing ratio are used, the same autoclave reaction vessel is used, and the same hydrothermal synthesis conditions are set at 130 ° C. as described above. A porous ferrite film having a thickness of 250 μm was produced by repeating the reaction process for 20 hours in the same manner. The porous ferrite film obtained here is the same as the porous ferrite film of the heat insulation layer of the conventional heat insulation mold. One of these two sheets was used as a comparative sample on which the heat insulating film B was formed. The remaining one sheet was impregnated with the above-mentioned porous ferrite film with the liquid raw material having the same composition in the same manner as the process shown in FIG. 3, and the same solidification treatment and heat treatment in the atmosphere were performed. Thus, the sample in which the heat insulation film | membrane A (film thickness of 250 micrometers) which is the same heat insulation layer as the heat insulation metal mold | die of this invention was formed was obtained.

  With respect to each of the heat insulating film A and the heat insulating film B formed on the substrate, the composition was analyzed using a fluorescent X-ray apparatus, and the crystal structure was examined by X-ray diffraction analysis using CuKα rays. As a result of the composition analysis, iron, silicon and tin were detected in the heat insulating film A. In this analysis method, boron, oxygen, etc., which are light elements below chlorine, cannot be detected. However, triethyl borate used as a raw material is a highly hydrolyzable substance, so the constituent element boron is porous ferrite. It is surmised that it remains in the hydrolysis product solidified in the pores of the membrane. Since this solidified hydrolysis product is calcined at 300 ° C. in the atmosphere to obtain a solid substance, it is considered that this solid substance has a composition of at least silicon, tin, boron and oxygen. On the other hand, in the heat insulation film B, only iron was detected as a metal element.

FIG. 5 shows X-ray diffraction patterns of the heat insulating film A (“(a) the heat insulating layer of the present invention” in FIG. 5) and the heat insulating film B (“(b) a conventional heat insulating layer” in FIG. 5). As shown in FIG. 5, it can be seen that the heat insulating layer B is composed of a crystal phase that can be identified as spinel iron oxide (= iron ferrite) having a lattice constant a ₀ = 8.40 、, Fe ₃ O ₄ . On the other hand, the heat insulation film A is a spinel type iron oxide (= iron ferrite) having a lattice constant a ₀ = 8.40 、, a phase having high crystallinity that can be identified as Fe ₃ O ₄ , and 2 ° has a vertex at 22 ° of 15 °. It was confirmed that the solid material was made of an amorphous substance (that is, Si—B—Sn—O-based inorganic oxide glass) showing a broad peak in a range of ˜35 °.

  Furthermore, about the heat insulation film | membrane A and the heat insulation film | membrane B, the film | membrane surface and the cross section were observed using the scanning electron microscope (SEM). The observation surface of each sample was prepared by manually polishing the surface of the film using a number 1000 polishing sheet. Further, the film cross section was prepared by cutting the substrate into two by machining and manually polishing the cut surface using a No. 1000 polishing sheet. They were observed. Scanning electron microscope images of the polishing surface and the cross section of the heat insulating film A ("(a) the heat insulating layer of the present invention" in FIG. 6) and the heat insulating film B ("(b) conventional heat insulating layer" in FIG. 6) are shown. It is shown in FIG. Unlike the heat insulation film B, the heat insulation film A was found to have white amorphous particles. Considering the result of the composition analysis and the result of the X-ray diffraction analysis, it can be determined that these amorphous particles are made of Si—B—Sn—O based inorganic oxide glass.

  The porosity of the heat insulation film A and the heat insulation film B was also measured. The heat insulating film A and the heat insulating film B after the above analysis were used as measurement samples. The measurement of the porosity was performed according to the non-contact surface roughness measurement method using a laser microscope disclosed in Patent Document 2. The measurement sample was a No. 1000 polishing sheet, and the surface was roughly polished from the film surface to a depth of about 50 μm, and then carefully hand polished using a No. 4000 wrapping film sheet to prepare a smooth surface for measuring the porosity. Here, the measurement sample of the heat insulation film A is amorphous solid material particles made of Si—B—Sn—O-based inorganic oxide glass in the voids scattered in the porous ferrite layer. There is a possibility that a large error occurs in the accuracy of the non-contact surface roughness due to the transmission of light. In order to prevent this measurement error, a palladium film having a thickness of 0.1 μm was formed on the measurement surface by using a direct current sputtering apparatus, and this was used as a measurement sample.

For each measurement sample, four square regions having a side of 150 μm were extracted from the entire sample surface in order to measure the porosity. As shown in FIG. 20 (a), using a non-contact surface roughness measurement method using a laser microscope (magnification 2000 times at the time of measurement), the uneven shape in the depth direction for each extracted square region Was measured. That is, the straight portion (length 150 μm) on the upper side of the square region was measured, the cross-sectional image was cut out, and the unevenness was measured in the depth profile (FIG. 20B) of the obtained uneven shape. The total ratio (FIG. 20 (c)) of the horizontal distance of the concave portion having a depth of 5 μm from the surface with respect to the total distance of 150 μm was defined as the ratio (porosity) Pa _{1 of the} pores existing on the measurement line.

In the same manner, parallel to the upper horizontal side of the above-mentioned square region, the vertical sides of 150 μm are spaced at intervals of 25 μm, and from the depth profile of the concavo-convex shape of the cross-section of the straight line connecting the both ends (distance 150 μm), was porosity was determined and the porosity Pa of the square regions the values of the porosity Pa ₁ ～Pa ₇ obtained from all seven straight portions and arithmetic mean. Similarly, the porosity Pa, Pb, Pc, and Pd of four square regions in the measurement sample were respectively obtained, and the porosity P of the heat insulating film A was calculated from the arithmetic mean value thereof. As a result, the porosity of the heat insulation film A was 10%, and the porosity of the heat insulation film B was 53%. Calculation from this value shows that 81% by volume of the voids in the porous membrane are filled with a solid material.

Evaluation of heat insulation About the same layer structure as the heat insulation metal mold | die of this invention, the heat insulation performance of the said 2 types of heat insulation film | membrane A and the heat insulation film | membrane B was evaluated. Sample 21 for thermal insulation evaluation and comparative sample 32 having a heat insulating layer made of the same material and the same structure as the heat insulating film A or B and further having a metal film formed thereon were prepared. FIG. 7 shows a schematic cross-sectional configuration diagram of the sample 21 in which the heat insulating film A is arranged. The comparative sample 32 is the same as the configuration shown in FIG. 7 except that the material of the heat insulating film is the heat insulating film B. Sample 21 was produced as follows. First, a rectangular parallelepiped (material: carbon steel) block having a square bottom with a side of 30.0 mm and a height of 100.0 mm is prepared, with a diameter of 3.5 mm at the center of the side surface at a height of 90 mm from the bottom. A thermocouple mounting hole 29 having a depth of 15.0 mm was formed to produce a metal substrate 22. Similar to the method of forming the heat insulating film A using the metal substrate 22, a metallic film 23 made of an iron film having a thickness of 3 μm is formed from the bottom to a position of 5.0 mm, and a thickness of 210 μm is formed thereon. The heat insulating layer 24 made of the same heat insulating film A as the heat insulating layer 4 of the heat insulating mold 1 of the present invention was formed.

  Subsequently, the portion excluding the heat insulating layer 24 is masked, and the apparatus used for forming the heat insulating mold 1 and the first heat conductive layer 6a of the present invention is used, and the sputtering method is performed under the same film forming conditions. The bonding layer 25 made of titanium having the same thickness as the bonding layer 5 of the heat insulating mold 1 of the invention and the first heat conductive layer 26a made of copper of 2 μm were formed. Further, for the metal base material formed up to the first heat conductive layer 26a, the other lower part is masked except for only the flat portion on the upper surface, and copper sulfate electroplating is performed, so that the second heat of 18 μm thickness is obtained. Conductive layer 26b was formed.

  Thereafter, a first metal film 27a made of nickel having a thickness of 2 μm was coated by a nickel strike plating method. Further, a second metal film 27b made of an amorphous nickel phosphorus alloy film having a thickness of 20 μm is formed on the two metal films continuously by an electroless plating method made of different plating solutions. A sample 21 was produced by forming the metal film 27 thus formed. For comparison of the thermal insulation evaluation, instead of the thermal insulation layer 24 made of the thermal insulation film A of the sample 21, the comparative sample 32 in which the thermal insulation layer made of the thermal insulation film B having the same thickness of 210 μm was formed. Got ready. Furthermore, a second comparative sample 33 having no heat insulating film was also produced for the purpose of evaluating the same heat insulating property. The second comparative sample 33 has a configuration in which the metal film 23, the heat insulating layer 24, and the bonding layer 25 are removed from the sample 21.

  In FIG. 8, the schematic sectional drawing of the heat insulation evaluation apparatus 31 used by the present Example is shown. This apparatus has a structure in which a highly conductive metal plate 35 made of stainless steel having a size of 100 mm × 150 mm and a thickness of 4 mm is disposed on an electric heater 34. Due to this configuration, the entire surface of the metal plate 35 has a uniform temperature during heating. The above three types of sample 21, comparative sample 32, and second comparative sample 33 were coated with thermally conductive silicon grease on their bottom surfaces and placed on the surface of this metal plate 35. Thermocouples 36, 37, and 38 are attached to the thermocouple attachment holes of the sample 21, the comparative sample 32, and the second comparative sample 33, respectively, and the temperature of each metal substrate inserted by them is a multi-temperature recorder. 39 can be recorded. That is, the evaluation of heat insulation was performed by simultaneously heating each sample uniformly by operating the electric heater 34, and measuring the temperature of the metal base material of each sample, and comparing how the temperature rises. . In addition, in the temperature measurement of heat insulation evaluation, the evaluation apparatus was covered with the heat insulation cover 40 in order to make each metal base material of a sample hard to be influenced by external air.

  Evaluation of heat insulation was performed by starting heating from room temperature using the electric heater 34 and examining how the temperature of each sample increased for 60 minutes. The result is shown in FIG. Since the sample 21 having the heat insulating film A of the present invention has a slower temperature rise of the metal base material than the second comparative sample 33 without the heat insulating film, the presence of the heat insulating film A makes it difficult to transfer heat to the metal base material. It can be seen that there is an effect, that is, the heat insulating film A contributes to the heat insulating effect. Moreover, it turns out that the heat insulation film | membrane A of this invention has a heat insulation property substantially equivalent to the conventional heat insulation film | membrane B. FIG.

Evaluation of heat insulating layer strength In this example, the compressive strength of the heat insulating layer 4 (that is, the heat insulating film A) was also evaluated. For the compressive strength, a sample 41 having a heat insulating layer 44 similarly manufactured using the same material as that of the heat insulating layer 4 of the heat insulating mold 1 of this embodiment is manufactured, and the change in film thickness due to the compression pressure of the heat insulating layer is examined. Was evaluated by FIG. 10 shows a perspective view of the appearance of the sample 41 and a cross-sectional view cut along a plane connected by W-XYZ in the perspective view. A sample 41 has a square shape with a side of 40 mm and a stainless steel substrate 42 with a thickness of 10 mm and a metal film 43 (thickness 3 μm) made of square iron with a size of 10 mm on a side and a heat insulating layer 44 (thickness). 150 μm) of laminated films are arranged. That is, first, the same method as the metallic film 3 and the heat insulating layer 4 of the heat insulating mold 1 of the present embodiment is used on the entire surface of the stainless steel substrate having the above-mentioned size, and the thickness of the same composition is 3 μm. A laminated film composed of the metallic film and a heat insulating layer having a thickness of 200 μm was formed. Subsequently, by using a grinding machine, the remaining part is removed by cutting so that only the square shape with a side of 10 mm on the side of the central part of the substrate 42 is left, and the thickness of the heat insulating layer becomes 150 μm. Thus, the laminated film of the metal film 43 and the heat insulation layer 44 was processed so that the surface was smooth, and the sample 41 was produced.

  The evaluation apparatus shown in FIG. 11 was used for the evaluation of the compressive strength of the heat insulating layer. The evaluation device 45 includes a sample table 46, a mount 47 installed on the sample table 46, and a hydraulic cylinder 48 attached to the mount 47. A pressing jig 50 is attached to the tip of the piston rod 49 of the pressure cylinder 48. The pressing jig 50 has a smooth bottom surface with a diameter of 30 mm, and has an internal structure designed so that the pressing pressure of the piston rod 49 is evenly applied to the surface of the sample 41. The sample 41 was placed on the sample table 46 and arranged between the sample table 46 and the pressing jig 50 arranged on the upper side. The compression strength is evaluated by operating the hydraulic cylinder 48 to push down the piston rod 49 and press the heat insulating layer 44 having a square surface of 10 mm on one side on the bottom surface of the pressing jig 50. This was done by measuring the change in the thickness of the heat insulating layer 44 due to the applied compression pressure. FIG. 12 shows the amount of change in the shrinkage of the indentation pressure generated by using the hydraulic cylinder 48 and the thickness of the heat insulating layer 44 (that is, the amount of depression). For comparison, the same heat insulating film B as the heat insulating layer of the conventional mold was formed in place of the heat insulating layer 44 of the above-described sample 41 to produce a comparative sample. The same measurement is performed for this comparative sample, and the relationship between the indentation pressure and the amount of depression is shown in FIG.

  As can be seen from FIG. 12, the same heat insulating film B as the heat insulating layer of the conventional heat insulating mold showed a large dent amount, and the dent amount further increased as the pushing pressure was increased. However, in the heat insulating film A corresponding to the heat insulating layer 54 of the heat insulating mold of the present invention, the dent amount is hardly detected at an indentation pressure of 1 ton per square centimeter, and the dent amount is further detected at an indentation pressure of 5 ton per square centimeter. It can be seen that is hardly detected. That is, it can be seen that the heat insulating layer of the heat insulating mold of the present invention has higher compressive strength than the heat insulating layer of the conventional heat insulating mold.

Evaluation of Thermal Conductivity of Thermal Conductive Layer The thermal conductivity was evaluated for the purpose of examining the effect of the thermal conductive layer of the heat insulating mold of the present invention. Evaluation of thermal conductivity is performed by preparing a sample 51 of a substrate on which a metal film having a thermal conductive layer is formed as an underlayer and a comparative sample 72 of a substrate on which only a metal film having no thermal conductive layer is formed, and evaluating the thermal conductivity. I went by the method. Sample 51 was produced as follows. That is, the substrate 52 (size: length 10.0 mm × width 6.7 mm × thickness) made of stainless steel SUS304 (thermal conductivity at 100 ° C .: 16.3 W / m · K), which is a metal material having low thermal conductivity. 0.3 mm), a first heat conductive layer made of copper having a thickness of 2 μm is formed by sputtering on the surface in the same manner as in the heat insulating mold of the present invention of Example 1, and subsequently thickened by electrolytic plating. A second heat conductive layer made of copper having a thickness of 18 μm was laminated and combined to form a heat conductive layer 56 made of copper having a thickness of 20 μm. Further, after a first metal film (nickel) having a thickness of 2 μm is formed on the heat conductive layer 56 by a nickel strike plating method, a second metal film (amorphous nickel) having a thickness of 100 μm is continuously formed by an electroless plating method. A metal film 57 having a thickness of 102 μm was formed by stacking and combining (phosphorus alloy). In addition, the comparative sample 72 is formed by directly forming a 2 μm-thick first metal film (nickel) on a SUS304 substrate of the same size by a nickel strike plating method, and then continuously forming a 100 μm-thickness by an electroless plating method. A second metal film (amorphous nickel phosphorus alloy) was formed, and a metal film having a thickness of 102 μm, which was the same as that of sample 51, was formed.

  FIG. 13 shows a schematic cross-sectional view of the thermal conductivity evaluation apparatus 71 used in this example. A schematic cross-sectional configuration diagram of the sample 51 and the comparative sample 72 is also shown in FIG. This apparatus has a structure in which a highly conductive metal plate 75 is disposed on an electric heater 74. The metal plate 75 is made of a processed body of a metal copper block, and a 20 mm portion from the lower ends of the sample 51 and the comparative sample 72 can be closely attached and fixedly held. Due to this configuration, the lower ends of the sample 51 and the comparative sample 72 fixed to the metal plate 75 are set to a uniform temperature during heating. Each of the sample 51 and the comparative sample 72 is protected by being closely adhered to the surface by two heat insulating plates 73 made of ethylene tetrafluoride resin, and the surface of the metal film 57 at a position 5 mm from the upper end of each is heat-insulated. Thermocouples 76 and 77 are attached between the plates 73, respectively, so that the temperature of each metal film surface can be recorded in the multi-temperature recorder 79. Evaluation of thermal conductivity was performed by simultaneously heating the lower part of each sample from room temperature by operating the electric heater 74 and measuring the temperature rise of the metal film near the upper end of each sample. In order to make the temperature of the sample surface less susceptible to the influence of outside air, a heat insulating cover 80 was attached to the evaluation device during the thermal conductivity evaluation.

  The results of the sample having the heat conductive layer and the comparative sample without the heat conductive layer are shown in FIGS. 14 (a) and 14 (c), respectively. The sample 51 having the heat conductive layer 56 of the present invention has a faster temperature rise of the metal film than the comparative sample 72 having no heat conductive layer, so that the heat conductive layer diffuses the heat energy of the heat source and is far from the heat source. It turns out that there exists an effect which makes it easy to transmit a thermal energy to the metal film in a position.

Example 2
In the heat insulation mold 1 of the present invention in Example 1, the solid material constituting the heat insulation layer 4 is changed to an inorganic oxide glass mainly composed of main silicon and boron, and further the bonding layer 5 and the first heat conductive layer 6a. Were changed to a 0.02 μm thick titanium film and a 4 μm thick copper film, respectively. Further, the second heat conductive layer 6b is omitted. That is, the heat conductive layer 6 is only a copper film having a thickness of 4 μm. Except for these points, the configuration was the same as that of the heat insulating mold of Example 1.

  The solid material constituting the heat insulating layer is impregnated in the voids of the porous ferrite film prepared in advance by the same method as in Example 1 using the following liquid material instead of the liquid material shown in Example 1, and the atmosphere Prepared by firing in. As the liquid raw material, 40 ml of ethyl silicate, 80 ml of triethyl borate and 0.7 g of ammonium ammonium fluoride were mixed solvent 80 ml (the mixed solvent used here was ion-exchanged water: ethanol: 2-propanol = 1: 1: 5). (Prepared in (volume ratio)), a total of 200 ml of the mixed solution obtained by mixing and dissolving in the atmosphere at room temperature was used.

In the same manner as the sample on which the heat insulating film A of Example 1 was formed, regarding the heat insulating film formed on the substrate in this example, X-ray diffraction analysis by CuKα ray and the surface and cross section of the film were scanned with an electron microscope (SEM). ). The X-ray diffraction pattern is shown in FIG. In addition to the highly crystalline phase that can be identified for iron ferrite (Fe ₃ O ₄ ), an amorphous material that exhibits a broad peak in the range of 2θ = 15 ° to 35 ° having an apex at 2θ = 22 ° (ie, Si -B—O-based inorganic oxide glass) and a solid material phase that is considered to be composed of a mixture of substances suggesting highly crystalline silicic acid-based compounds exhibiting sharp peaks at 2θ = 14 ° and 28 °. Recognize.

  Further, from the observation result by the scanning electron microscope, as in FIG. 6 of Example 1, amorphous particles that appear white that can be judged as a solid material in the voids scattered in the porous ferrite layer constituting the conventional heat insulating layer are shown. I found it. Together with the result of the composition analysis and the result of the X-ray diffraction analysis, these amorphous particles can be judged as a solid material composed of a mixture of Si—B—O based inorganic oxide glass and a crystalline silicic acid based compound.

  In addition, the porosity of the heat insulation film | membrane A was 12%. It was found that 77% by volume of the voids in the porous membrane were filled with the solid material.

  The method for forming the laminated film of the bonding layer was the same as in Example 1, and the film formation time was changed to 12 seconds for titanium film formation and 10 minutes for copper film formation.

  The heat insulation and the heat insulation layer strength were evaluated using the same evaluation method as in Example 1. It was confirmed that the heat insulation performance and compressive strength equivalent to those of Example 1 were obtained. Further, regarding the evaluation of thermal conductivity, the same evaluation as in Example 1 was performed using a copper film having the same thickness of 4 μm as the thermal conductive layer in Example 2. The result is shown in FIG. The effect of thermal conductivity due to the presence of the thermal conductive layer can be confirmed. Therefore, it was confirmed that the configuration of Example 2 is also effective as a heat insulating mold that achieves both high heat insulating performance and high compressive strength.

Example 3
In the heat insulation mold 1 of the present invention in Example 1, the solid material constituting the heat insulation layer 4 is changed to an inorganic oxide glass whose main components are silicon, titanium and boron, and the bonding layer 5 and the first The heat conductive layer 6a was changed to a tantalum film having a thickness of 0.05 μm and a copper film having a thickness of 1 μm. The second heat conductive layer 6b was not changed. As a result, the thickness of the heat conductive layer 6 was changed to 19 μm. Except for these points, the configuration was the same as that of the heat insulating mold of Example 1.

  The solid material constituting the heat insulating layer is impregnated in the voids of the porous ferrite film prepared in advance by the same method as in Example 1 using the following liquid material instead of the liquid material shown in Example 1, and the atmosphere It was produced by firing inside. As the liquid raw material, 33 ml of ethyl silicate, 7 ml of tetraisopropyl orthotitanate, 80 ml of triethyl borate and 0.7 g of ammonium ammonium fluoride were mixed in 80 ml of mixed solvent (the mixed solvent used here is the same as in Example 3). A total of 200 ml of the mixed solution obtained by mixing and dissolving at room temperature was used.

In the same manner as in Example 1, regarding the heat insulating film formed on the substrate in this example, the X-ray diffraction analysis using CuKα rays and the surface and cross section of the film were observed using a scanning electron microscope (SEM). The X-ray diffraction pattern is similar to the pattern of FIG. 15 (1) of Example 3, and has a highly crystalline phase that can be identified as iron ferrite (Fe ₃ O ₄ ) and a vertex 15 at 2θ = 22 °. Amorphous material showing a broad peak in the range of ° to 35 ° (ie, Si—B—Ti—O inorganic oxide glass) and high crystallinity showing sharp peaks at 2θ = 14 ° and 28 ° It was a mixed phase of a solid material considered to consist of a mixture of substances suggesting silicic acid compounds.

  Further, from the observation result by the scanning electron microscope, as in FIG. 6 of Example 1, amorphous particles that appear white that can be judged as a solid material in the voids scattered in the porous ferrite layer constituting the conventional heat insulating layer are shown. I found it. In consideration of the result of the composition analysis and the result of X-ray diffraction analysis, these amorphous particles are solid materials composed of a mixture of Si-B-Ti-O inorganic oxide glass and a crystalline silicate compound. It can be judged.

  In addition, the porosity of the heat insulation film | membrane A was 12%. It was found that 77% by volume of the voids in the porous membrane were filled with the solid material.

  The method for forming the laminated film of the bonding layer was the same as in Example 1, and the film formation time was changed to 25 seconds for tantalum film formation and 2 minutes 30 seconds for copper film formation.

  With respect to the heat insulating property, the heat insulating layer strength, and the heat conductivity of the heat conductive layer, evaluation was performed using the same evaluation method as in Example 1. It was confirmed that the heat insulation performance and compressive strength equivalent to those of Example 1 were obtained. Moreover, the effect of the heat conductive layer was also confirmed. The configuration of Example 3 was also found to be effective as a heat insulating mold that achieves both high heat insulating performance and high compressive strength.

Example 4
In the heat insulating mold 1 of the present invention in Example 1, the solid material constituting the heat insulating layer 4 is changed to a substance composed of an inorganic oxide glass whose main components are silicon, zircon and tin, and further the bonding layer 5. Was changed to an iron film having a thickness of 0.2 μm. Except for these points, the configuration was the same as that of the heat insulating mold of Example 1.

  The solid material constituting the heat insulating layer is impregnated in the voids of the porous ferrite film prepared in advance by the same method as in Example 1 using the following liquid material instead of the liquid material shown in Example 1, and the atmosphere Prepared by firing in. As the liquid raw material, 115 ml of ethyl silicate, 70 ml of zirconium (IV) propoxide (approx. 70%, 1-propanol solution), 2 ml of tin 2 ethylhexanoate, 3 ml of 0.1N-hydrochloric acid, and 10 ml of ion-exchanged water in the air In total, 200 ml of the mixed solution obtained by mixing at room temperature was used.

In the same manner as the sample on which the heat insulating film A of Example 1 was formed, regarding the heat insulating film formed on the substrate in this example, X-ray diffraction analysis by CuKα ray and the surface and cross section of the film were scanned with an electron microscope (SEM). ). The X-ray diffraction pattern is shown in FIG. In addition to the highly crystalline phase that can be identified as iron ferrite (Fe ₃ O ₄ ), an amorphous substance (ie, Si—Zr) having a peak broadened in the range of 15 ° to 40 ° having an apex at 2θ = 25 °. It can be seen that there is a solid material phase made of (Sn—O-based inorganic oxide glass).

  Further, from observation with a scanning electron microscope, as in FIG. 6 of Example 1, there are amorphous particles that appear white that can be judged as a solid material in voids scattered in the porous ferrite layer constituting the conventional heat insulating layer. I understood it. In view of the result of the composition analysis and the result of the X-ray diffraction analysis, these amorphous particles can be determined as a solid material made of Si—Zr—Sn—O based inorganic oxide glass.

  The porosity of the heat insulating film A was 10%. It was confirmed that 81% by volume of voids in the porous membrane were filled with a solid material.

  The bonding layer 5 was formed by the same method as in Example 2, and the film formation time was changed to 1 minute for iron film formation.

  The heat insulation and the heat insulation layer strength were evaluated using the same evaluation method as in Example 1. It was confirmed that the heat insulating performance and compressive strength equivalent to those of Example 1 were obtained. It was confirmed that the configuration of this example is also effective as a heat insulating mold that achieves both high heat insulating performance and high compressive strength.

Example 5
In the same manner as in Example 1, the bonding layer 5 was changed to a tungsten film having a thickness of 0.2 μm, and the heat conductive layer 6 was changed to a copper film having a thickness of 6 μm. As the formation conditions, the respective film formation times were changed to 1 minute 45 seconds for the tungsten film formation and 15 minutes for the copper film formation. Except for these points, the configuration was the same as that of the heat insulating mold of Example 1.

  The heat insulation and the heat insulation layer strength were evaluated using the same evaluation method as in Example 1. It was confirmed that the heat insulation performance and compressive strength equivalent to those of Example 1 were obtained. It was confirmed that the configuration of this example is also effective as a heat insulating mold that achieves both high heat insulating performance and high compressive strength.

Example 6
In the same manner as in Example 1, the bonding layer 5 was changed to a molybdenum film having a thickness of 0.8 μm. As the formation conditions, the film formation time was changed to 5 minutes. Except for these points, the configuration was the same as that of the heat insulating mold of Example 1.

  The heat insulation and the heat insulation layer strength were evaluated using the same evaluation method as in Example 1. It was found to have the same heat insulating performance and compressive strength as Example 1. It was confirmed that the configuration of this example is also effective as a heat insulating mold that achieves both high heat insulating performance and high compressive strength.

Example 7
In the same manner as in Example 1, the bonding layer 5 was changed to a chromium film having a thickness of 0.2 μm. As the formation conditions, the film formation time was changed to 50 seconds. Except for these points, the configuration was the same as that of the heat insulating mold of Example 1.

  The heat insulation and the heat insulation layer strength were evaluated using the same evaluation method as in Example 1. It was found to have the same heat insulating performance and compressive strength as Example 1. It was confirmed that the configuration of this example is also effective as a heat insulating mold that achieves both high heat insulating performance and high compressive strength.

Example 8
In the same manner as in Example 1, the bonding layer 5 was changed to an iron film having a thickness of 4 μm. As the formation conditions, the film formation time was changed to 10 minutes. Except for these points, the configuration was the same as that of the heat insulating mold of Example 1.

  The heat insulation and the heat insulation layer strength were evaluated using the same evaluation method as in Example 1. It was found to have the same heat insulating performance and compressive strength as Example 1. It was confirmed that the configuration of this example is also effective as a heat insulating mold that achieves both high heat insulating performance and high compressive strength.

  The mold of the present invention having a heat insulating layer made of ceramics with high mechanical strength against compressive stress has excellent durability in mold strength of the molding surface against long-term repeated use of resin molding. Since it is possible, for example, it is useful as a long-life heat insulating mold for resin molding of complex shapes such as optical elements and fine pattern shaped molded bodies. It can also be applied to uses such as a mold for nanoimprinting.

Claims (9)

A mold having a heat insulating layer between a metal mold base material and a metal film constituting the molding surface,
(1) The heat insulating layer includes: 1) a porous film formed by connecting ferrite crystal particles in a three-dimensional network; and 2) a solid material filled in at least a part of voids in the porous film. Including
(2) Between the heat insulation layer and the metal film, a thermal conductivity layer having a thermal conductivity at 100 ° C. of 100 W / m · K or more is provided.
Insulation mold characterized by that. The porous film is formed by hydrothermal synthesis reaction of 1) the surface of a metal mold base material or 2) the surface of a metal layer previously formed on the surface of the mold base material. The heat insulation metal mold | die of Claim 1. The ferrite has the following general formula A _x Fe _3−x O ₄ (where A represents at least one metal element that can be substituted for the Fe site constituting the spinel-type iron oxide crystal, and x is 0 ≦ x <1. Meet)
The heat insulation metal mold | die of Claim 1 or 2 which is a compound which has a spinel type crystal structure shown by these. The heat insulation metal mold | die of Claim 3 whose said A is at least 1 sort (s) of Ca, Zn, Mn, Al, Cr, Li, and Mg. The heat insulation metal mold | die in any one of Claims 1-4 whose solid material is inorganic oxide glass. The inorganic oxide glass is at least one of 1) borosilicate glass, 2) silica glass, and 3) glass containing at least one of aluminum, titanium, zirconium, tin and iron. Insulation mold. The heat insulating mold according to any one of claims 1 to 6, wherein the solid material is produced by impregnating the pores with a liquid raw material of an inorganic oxide and then heat-treating in an oxidizing atmosphere. The heat insulation metal mold | die of Claim 7 in which a liquid raw material contains the precursor compound and solvent of an inorganic oxide. The heat insulation metal mold | die in any one of Claims 1-8 used for shaping | molding of the composition containing a resin component.