Method for manufacturing magnetic recording medium and heat treatment apparatus used therein

Abstract

The purpose of the present invention is to provide a method for producing a magnetic recording medium, which can stably produce a magnetic recording medium in which ozone generation is suppressed and which has good bonding force between a protective film layer and a lubricant layer. The method for manufacturing a magnetic recording medium according to the present invention is a method for manufacturing a magnetic recording medium in which at least a magnetic layer, a protective film layer, and a lubricant layer are laminated in this order on a non-magnetic substrate, and the surface of the lubricant layer is heat-treated by illumination from an LED light source.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a magnetic recording medium and a heat treatment device used therein. Background Art

[0002] A hard disk device used as a storage device of an information processing device has a magnetic head for regeneration and recording and a magnetic recording medium having a magnetic layer. In the magnetic recording medium, the durability of the magnetic recording medium is deteriorated due to wear damage caused by contact and sliding with the magnetic head. In order to prevent this, a protective film layer and a lubricant layer are provided on the magnetic layer. As the protective film layer, a hard carbon film is generally used in the past. The lubricant layer is generally formed by applying a liquid perfluoropolyether compound or the like on the surface.

[0003] It is known that various treatments are applied to the lubricant layer for the purpose of improving the bonding strength of the protective film layer to the lubricant layer. For example, Patent Document 1 discloses a method of applying a heat treatment to the applied lubricant layer and then irradiating the layer with an ultraviolet lamp. It is also disclosed that the irradiation treatment is performed in an inert gas atmosphere or in a vacuum in order to suppress the generation of ozone during the irradiation treatment.

[0004] [Prior art literature]

[0005] [Patent Literature]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 11-25452 Summary of the invention

[0007] [Problems to be solved by the invention]

[0008] It is clear here that the light of the ultraviolet lamp decomposes oxygen to produce ozone. Therefore, although the light treatment is carried out in an inert gas atmosphere or in a vacuum, a small amount of ozone is produced, and the ozone decomposes and destroys the lubricant molecules contained in the lubricant layer.

[0009] When investigating the cause of the ozone generation, it was found that a small amount of oxygen adsorbed on the surface of the magnetic recording medium was brought into the processing device and decomposed into ozone. The elemental oxygen of ozone comes from, for example, moisture adsorbed on the substrate and the inner wall of the device. When the lubricant layer is processed in the atmosphere, the interior of the processing device is filled with an inert gas atmosphere, and a lot of atmospheric components are also brought into the processing device. In addition, it is difficult for an ultraviolet lamp to obtain parallel light, and the light diffuses to the surroundings, so that the processing substrate of the processing device is also irradiated with light, thereby, oxygen adsorbed on the inner wall of the processing device is also decomposed into ozone.

[0010] In order to suppress the decomposition of oxygen, an ultraviolet lamp with a peak wavelength range that does not allow ozone to be generated is used. Ultraviolet lamps also contain weak light of various wavelengths outside the peak wavelength, so the weak light will decompose oxygen and produce ozone.

[0011] In view of the above situation, one embodiment of the present invention aims to provide a method for manufacturing a magnetic recording medium and a heat treatment device used therein, which can stably manufacture a magnetic recording medium that suppresses ozone generation and has good bonding strength between a protective film layer and a lubricant layer.

[0012]

Methods to solve the problem

[0013] In order to achieve the above object, the present invention adopts the following structure.

[0014] (1) A method for producing a magnetic recording medium, wherein at least a magnetic layer, a protective film layer, and a lubricant layer are sequentially laminated on a non-magnetic substrate.

[0015] The surface of the lubricant layer is heated by light from an LED light source.

[0016] (2) According to the method for manufacturing a magnetic recording medium described in (1), the light emitted from the LED light source has a central wavelength of less than 500 nm, and the central wavelength does not include a wavelength range of 170 nm to 190 nm.

[0017] (3) The method for producing a magnetic recording medium according to (1) or (2), wherein the heat treatment is performed at a pressure close to atmospheric pressure.

[0018] (4) The method for producing a magnetic recording medium according to any one of (1) to (3), wherein the heat treatment is performed in an air atmosphere.

[0019] (5) The method for producing a magnetic recording medium according to any one of (1) to (4), wherein the heat treatment is performed for no longer than 60 seconds.

[0020] (6) A heat treatment device used in the method for producing a magnetic recording medium according to any one of (1) to (4), comprising:

[0021] a first LED light source that emits light to one side of the substrate to heat the substrate,

[0022] a second LED light source that emits light to the other side of the substrate to heat the substrate,

[0023] A mechanism in which the outer peripheral end of the substrate is supported by a supporting component so that the substrate can be inserted and removed between the first LED light source and the second LED light source.

[0024] (7) In the heat treatment apparatus according to (6), 50% or more of the light from the first LED light source and 50% or more of the light from the second LED light source are directly irradiated onto the substrate.

[0025] (8) In the heat treatment device according to (6) or (7), the distance between the first LED light source and the second LED light source and the substrate is 50 mm or less.

[0026] (9) In the heat treatment device according to any one of (6) to (8), the light emitted from the first LED light source and the second LED light source has a central wavelength of less than 500 nm and does not include a wavelength range of 170 nm to 190 nm.

[0027] (10) The heat treatment device according to any one of (6) to (9), further comprising a control device for causing the first LED light source and the second LED light source to emit light only when the substrate is disposed between the first LED light source and the second LED light source.

[0028] [Effects of the Invention]

[0029] According to a method for producing a magnetic recording medium according to one embodiment of the present invention, generation of ozone when the surface of the lubricant layer of the magnetic recording medium is heat-treated can be suppressed, thereby stably producing a magnetic recording medium having good bonding strength between the protective film layer and the lubricant layer.

[0030] In addition, a method for manufacturing a magnetic recording medium according to one embodiment of the present invention can make the light intensity from the LED light source in the irradiated surface approximately uniform, thereby manufacturing a magnetic recording medium with uniform in-plane distribution of the bonding force between the protective film layer and the lubricant layer.

[0031] In a heat treatment device in one embodiment of the present invention, the LED light source emits light only when a processing substrate is set between a pair of LED light sources, so that the heat light from one LED light source does not deteriorate the other LED light source, thereby achieving a long life. In addition, in a heat treatment device in one embodiment of the present invention, the LED light source emits light only during heat treatment, thereby reducing power consumption.

[0032] Furthermore, the heat treatment apparatus according to one embodiment of the present invention can be used in the atmosphere, and thus the productivity of the magnetic recording medium can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0033]

Figure 1

[0034]

Figure 2

[0035]

Figure 3

[0036] Hereinafter, the mode for implementing the present invention will be described with reference to the accompanying drawings. In addition, in order to facilitate the understanding of the description, the same symbols are given to the same structural elements in each drawing, and repeated descriptions are omitted. In addition, the scales of the components in the drawings are sometimes different from the actual ones. The "to" indicating a numerical range in this specification means that, unless otherwise specified, the numerical values ​​recorded before and after it are included as the lower limit and upper limit.

[0037] When describing the method for producing a magnetic recording medium according to an embodiment of the present invention and a heat treatment apparatus used therein, the magnetic recording medium obtained by the method for producing a magnetic recording medium according to the present embodiment will be described.

[0038] <Magnetic recording media>

[0039] Figure 1 1 is a schematic cross-sectional view showing an example of a magnetic recording medium. Figure 1 As shown, the magnetic recording medium 10 is a laminated body in which a magnetic layer 12 , a protective film layer 13 , and a lubricant layer 14 are laminated in this order on a non-magnetic substrate 11 .

[0040] In this embodiment, an example is given in which an adhesive layer (not shown), a soft magnetic base layer (not shown), a seed layer (not shown), and an orientation control layer (not shown) are sequentially stacked between the non-magnetic substrate 11 and the magnetic layer 12. The adhesive layer, the soft magnetic base layer, the seed layer, and the orientation control layer are provided as required, and some or all of them may not be provided.

[0041] As the non-magnetic substrate 11, a laminated body in which a film composed of NiP or a NiP alloy is formed on a substrate composed of a metal material such as Al or an alloy material such as Al alloy can be used. In addition, as the non-magnetic substrate 11, a substrate composed of a non-metallic material such as glass, ceramic, silicon, silicon carbide, carbon, resin, etc. can be used, and a laminated body in which a film composed of NiP or a NiP alloy is formed on a substrate composed of the non-metallic material can also be used.

[0042] The adhesive layer inhibits the corrosion of the non-magnetic substrate 11 when the non-magnetic substrate 11 and the soft magnetic base layer provided on the adhesive layer are arranged in contact. As the material of the adhesive layer, for example, Cr, Cr alloy, Ti, Ti alloy, etc. can be appropriately selected. In order to fully obtain the effect brought by the provision of the adhesive layer, the thickness of the adhesive layer is preferably more than 2nm. The adhesive layer can be formed by, for example, a sputtering method.

[0043] In addition, in this specification, the thickness of the adhesive layer refers to the length in the direction perpendicular to the main surface of the adhesive layer. The thickness of the adhesive layer is, for example, the thickness when measuring any position in the cross section of the adhesive layer. In the cross section of the adhesive layer, when measuring multiple places at any position, it can be the average value of the thickness of these measurement positions. Other layers can also be measured by the same method as the thickness of the adhesive layer.

[0044] The soft magnetic base layer preferably has a structure in which a first soft magnetic film, an intermediate layer composed of a Ru film, and a second soft magnetic film are stacked in sequence. That is, the soft magnetic base layer preferably has an intermediate layer composed of a Ru film sandwiched between two soft magnetic films, whereby the upper and lower soft magnetic films of the intermediate layer have an anti-ferromagnetic coupling (Anti-Fero Coupling, AFC) bonding structure. By having the soft magnetic base layer have an AFC bonding structure, it is possible to improve resistance to external magnetic fields and resistance to the WATE (Wide Area Tack Erasure) phenomenon, which is a problem unique to perpendicular magnetic recording.

[0045] The film thickness of the soft magnetic base layer is preferably 15nm to 80nm, more preferably 20nm to 50nm. If the film thickness of the soft magnetic base layer is above 15nm, the magnetic flux from the magnetic head can be fully absorbed, and insufficient writing is suppressed, thereby suppressing the deterioration of the recording and reproducing characteristics. On the other hand, if the film thickness of the soft magnetic base layer is below 80nm, a significant reduction in productivity is suppressed.

[0046] The first soft magnetic film and the second soft magnetic film are preferably made of CoFe alloy. When the first soft magnetic film and the second soft magnetic film are made of CoFe alloy, a high saturation magnetic flux density Bs (1.4 (T) or more) can be achieved. In addition, the CoFe alloy used in the first soft magnetic film and the second soft magnetic film is preferably added with any one or more of Zr, Ta, and Nb. Thus, the amorphization of the first soft magnetic film and the second soft magnetic film can be promoted, the orientation of the seed layer formed on the soft magnetic base layer can be improved, and the floating amount of the magnetic head can be reduced.

[0047] The soft magnetic underlayer can be formed by, for example, sputtering.

[0048] The seed layer controls the orientation and crystal size of the orientation control layer and the magnetic layer 12 disposed thereon. By providing the seed layer, the magnetization direction of the magnetic layer 12 is more firmly fixed in a direction perpendicular to the non-magnetic substrate 11 while the component of the magnetic flux generated from the magnetic head in the perpendicular direction relative to the substrate surface becomes larger.

[0049] The seed layer is preferably made of a NiW alloy. When the seed layer is made of a NiW alloy, other elements such as B, Mn, Ru, Pt, Mo, and Ta may be added to the NiW alloy as required.

[0050] The thickness of the seed layer is preferably 2 nm to 20 nm. If the thickness of the seed layer is 2 nm or more, the effect of providing the seed layer can be fully obtained. If the thickness of the seed layer is 20 nm or less, the increase in the size of the crystal can be suppressed.

[0051] The seed layer can be formed by, for example, a sputtering method.

[0052] The orientation control layer controls the orientation of the magnetic layer 12 well. The orientation control layer is preferably made of Ru or Ru alloy. The film thickness of the orientation control layer is preferably 5nm to 30nm. If the film thickness of the orientation control layer is less than 30nm, the distance between the magnetic head and the soft magnetic base layer is small, and the magnetic flux from the magnetic head can be steep. In addition, if the film thickness of the orientation control layer is more than 5nm, the orientation of the magnetic layer 12 can be well controlled.

[0053] The orientation control layer may be composed of a single layer or a plurality of layers. When the orientation control layer is composed of a plurality of layers, all of the orientation control layers may be composed of the same material or at least a part of the layers may be composed of different materials.

[0054] The orientation control layer can be formed by a sputtering method.

[0055] The magnetic layer 12 is composed of a magnetic film whose easy magnetization axis is oriented in a direction substantially perpendicular to the substrate surface of the non-magnetic substrate 11. The magnetic layer 12 contains Co and Pt, and may contain oxides, Cr, B, Cu, Ta, and Zr to further improve the SNR characteristics. Examples of the oxide contained in the magnetic layer 12 include SiO2, SiO, Cr2O3, CoO, Ta2O3, and TiO2.

[0056] The magnetic layer 12 may be a single-layer structure or a multi-layer structure with different compositions. For example, when the magnetic layer 12 is composed of three layers, namely, the first magnetic layer, the second magnetic layer, and the third magnetic layer, the first magnetic layer is preferably composed of a material having a granular structure composed of a material containing Co, Cr, Pt, and an oxide. As the oxide contained in the first magnetic layer, it is preferred to use oxides such as Cr, Si, Ta, Al, Ti, Mg, and Co. Among them, TiO2, Cr2O3, SiO2, etc. can be used appropriately. In addition, the first magnetic layer is preferably composed of a composite oxide to which two or more oxides are added. Among them, Cr2O3-SiO2, Cr2O3-TiO2, SiO2-TiO2, etc. can be used appropriately.

[0057] The second magnetic layer can be made of the same material as that of the first magnetic layer. The second magnetic layer is preferably made of a material having a granular structure.

[0058] The third magnetic layer is preferably composed of a material having a non-granular structure composed of a material containing Co, Cr, and Pt but not containing oxides. The third magnetic layer may contain one or more elements selected from B, Ta, Mo, Cu, Nd, W, Nb, Sm, Tb, Ru, Re, and Mn in addition to Co, Cr, and Pt. By containing the above elements in addition to Co, Cr, and Pt, the third magnetic layer can promote the miniaturization of magnetic particles or improve the crystallinity and orientation, so that the magnetic recording medium 10 can have recording and reproducing characteristics and thermal shock characteristics suitable for higher density recording.

[0059] The thickness of the magnetic layer 12 is preferably 5 nm to 25 nm. If the thickness of the magnetic layer 12 is 5 nm or more, sufficient reproduction output can be obtained and thermal shock characteristics can be maintained. In addition, if the thickness of the magnetic layer 12 is 25 nm or less, hypertrophy of magnetic particles in the magnetic layer 12 is suppressed, noise increase during recording and reproducing is suppressed, and deterioration of recording and reproducing characteristics represented by signal / noise ratio (S / N ratio) and recording characteristics (OW) is suppressed.

[0060] In order to achieve higher recording density, the magnetic layer 12 is preferably a perpendicular magnetic recording magnetic layer with its easy magnetization axis oriented substantially perpendicular to the substrate surface of the nonmagnetic substrate 11. The magnetic layer 12 may be an in-plane magnetic recording magnetic layer.

[0061] The magnetic layer 12 can be formed by any conventionally generally used method such as vapor deposition, ion beam sputtering, magnetron sputtering, etc. The magnetic layer 12 is usually formed by a sputtering method such as ion beam sputtering and magnetron sputtering.

[0062] The protective film layer 13 is provided on the upper surface of the magnetic layer 12 to protect the magnetic layer 12. As the protective film layer 13, carbon materials such as CVD carbon, amorphous carbon, hydrogen-containing carbon, nitrogen-containing carbon, fluorine-containing carbon, etc. formed by plasma CVD method, and ceramic materials such as silicon dioxide and zirconium oxide can be used. Among them, hard and dense CVD carbon is suitable for use not only from the perspective of durability but also from the perspective of economy and productivity. In order to improve durability while reducing the loss during recording and reproducing, the film thickness of the protective film layer 13 is set to 10 to 150 (1nm to 15nm), preferably 20 to 60 (2nm to 6nm).

[0063] The lubricant layer 14 is provided on the upper surface of the protective film layer 13 and is the uppermost layer of the magnetic recording medium 10. The lubricant layer 14 contains, for example, a polymer of a perfluoropolyether compound containing a polymerizable unsaturated group. As the perfluoropolyether compound containing a polymerizable unsaturated group, a compound having an organic group with a polymerizable unsaturated bond bonded to at least one end of the perfluoropolyether as the main chain can be used.

[0064] <Method for producing magnetic recording medium>

[0065] The method for manufacturing a magnetic recording medium according to the present embodiment includes a step (heating treatment step) of sequentially stacking a magnetic layer 12 and a protective film layer 13 on a non-magnetic substrate 11, stacking a lubricant layer 14 on the surface of the protective film layer 13, and then heating the surface of the lubricant layer 14 by irradiating light from an LED light source (a first LED light source 22 and a second LED light source 23 described later). The method for manufacturing a magnetic recording medium according to the present embodiment, by adopting such a heating treatment step, suppresses the generation of ozone by decomposition of oxygen in the heating treatment step, and thus can stably manufacture a magnetic recording medium having good bonding strength between the protective film layer 13 and the lubricant layer 14. In addition, the effect of improving the bonding strength between the protective film layer 13 and the lubricant layer 14 is caused by, in addition to the heating effect caused by the irradiation of light, the molecular structure of the lubricant molecules contained in the lubricant layer 14 is changed by the irradiation of light from the LED light source, thereby improving the bonding between the lubricant molecules contained in the lubricant layer 14 and the protective film layer 13, thereby obtaining a magnetic recording medium having good bonding strength between the protective film layer 13 and the lubricant layer 14.

[0066] That is, LED light sources are easier to obtain parallel light than conventional ultraviolet lamps, which suppress the diffusion of light to the surroundings, so that light is irradiated outside the processing substrate, and the decomposition of oxygen adsorbed on the walls of the device, etc., to produce ozone is suppressed. In addition, since the wavelength range of the emitted light is narrow, it is easy to design a light source that suppresses the decomposition of oxygen to produce ozone.

[0067] The light emitted from the LED light source (LED light) preferably has a central wavelength of less than 500 nm and does not include a central wavelength in the wavelength range of 170 nm to 190 nm. This is because light in the wavelength range of 170 nm to 190 nm often decomposes oxygen to generate ozone.

[0068] By using such an LED light source, the LED light decomposition of oxygen to produce ozone is suppressed. Therefore, in the manufacturing method of the magnetic recording medium involved in the present embodiment, the heat treatment can be carried out in the atmosphere, that is, under a pressure near the atmospheric pressure, in the atmospheric atmosphere, and at the same time, the heating device is also simple, thereby reducing the manufacturing cost of the magnetic recording medium and the manufacturing cost of the heating device.

[0069] LED light sources can emit directional light, so the directivity of the heat rays emitted from LED light sources is higher than that of other heating methods. Therefore, the heat rays are concentrated on the processing substrate of the heating device, and the components other than the processing substrate, that is, the supporting components of the processing substrate, the inner wall of the heating device, etc., are not exposed to the heat rays, thereby increasing the heating processing speed.

[0070] In the manufacturing method of the magnetic recording medium of the present embodiment, the heat treatment is preferably performed within 60 seconds, and more preferably within 20 seconds. By shortening the processing time in this way, the risk of contamination of the magnetic recording medium during the heat treatment can be reduced while reducing the manufacturing cost of the magnetic recording medium.

[0071] <Heat treatment equipment>

[0072] Figure 2 is a schematic cross-sectional view showing an example of a heat treatment apparatus used in manufacturing a magnetic recording medium according to an embodiment of the present invention, Figure 3 1 is a schematic oblique view showing an example of a light source of a heat treatment device. Figure 2 As shown, the heat treatment device 20 includes a first LED light source 22 for emitting (irradiating) light (first light ray) to one side (heat treatment surface) 21a of the substrate 21 to heat the substrate 21, a second LED light source 23 for emitting light (second light ray) to the other side (heat treatment surface) 21b of the substrate 21 to heat the substrate 21, and a mechanism 25 for supporting the outer peripheral end portion 21c of the substrate 21 by a supporting component 24 to allow the substrate 21 to move in and out between the first LED light source 22 and the second LED light source 23. Figure 2 In the figure, the mechanism 25 for allowing the substrate 21 and the supporting member 24 to enter and exit has the function of enabling the substrate 21 to be raised and lowered as indicated by the arrow.

[0073] In addition, if Figure 3 As shown in FIG. 1 , the LED light source 30 constituting the first LED light source 22 and the second LED light source 23 is composed of a large number of LED elements 32 mounted on a body 31 of the LED light source 30. Furthermore, the large number of LED elements 32 mounted on the body 31 of the LED light source 30 are arranged as shown in FIG. Figure 2 The two heat-treated surfaces 21 a and 21 b of the substrate 21 shown are opposed to each other.

[0074] Each LED element 32 is arranged so that the emitted light has directivity with the direction perpendicular to the main surface 31a of the main body 31 of the LED light source 30 as the central axis. The directivity of the LED element 32 is preferably ±60° or less with respect to the central axis.

[0075] Here, the angle of the directivity of the LED element 32 is defined as the angle relative to the central axis at which the illuminance is 50% when the illuminance of the central axis is 100% with the brightest light-emitting position of the LED element 32 as the central axis. In addition, the substrate 21 has an opening at the center, so the LED light source 30 may not be provided with the LED element 32 near the center of the body 31.

[0076] As described above, the heat treatment device 20 includes a first LED light source 22 and a second LED light source 23. The first LED light source 22 and the second LED light source 23 use Figure 3The LED light source 30 of the structure shown can perform high-speed heat treatment on the two surfaces (heat treatment surfaces 21a, 21b) of the substrate 21. Therefore, the heat treatment device 20 can perform high-speed heat treatment on the two surfaces of the magnetic recording medium by using the magnetic recording medium 10 on the substrate 21, thereby improving the productivity of the magnetic recording medium 10.

[0077] In the heat treatment device 20, preferably more than 50% of the light from the first LED light source 22 and more than 50% of the light from the second LED light source 23 are directly irradiated to the substrate 21. By adopting such a structure, the heat treatment device 20 can concentrate the heat light emitted from the first LED light source 22 and the second LED light source 23 on the substrate 21, and the parts other than the substrate 21 are not exposed to the heat light, thereby improving the processing speed while suppressing the generation of impurities.

[0078] In the heat treatment device 20, the distance L between the substrate 21 and the first LED light source 22 and the second LED light source 23 is preferably less than 50 mm. By adopting such a structure, the heat treatment device 20 can concentrate the heat rays emitted from the first LED light source 22 and the second LED light source 23 on the substrate 21, thereby increasing the processing speed.

[0079] In the heat treatment device 20, the light emitted from the first LED light source 22 and the second LED light source 23 preferably has a central wavelength of less than 500 nm, and the central wavelength does not include a wavelength range of 170 nm to 190 nm. By making the central wavelength of the light emitted from the first LED light source 22 and the second LED light source 23 not include a wavelength range of 170 nm to 190 nm, the decomposition of oxygen to generate ozone can be suppressed.

[0080] The heat treatment device 20 can reduce the generation of ozone by photodecomposition of oxygen by using the first LED light source 22 and the second LED light source 23 having the above-described structure.

[0081] The heat treatment device 20 preferably includes a control device that causes the first LED light source 22 and the second LED light source 23 to emit light only when the substrate 21 is disposed between the first LED light source 22 and the second LED light source 23. In addition, when the substrate 21 is disposed between the first LED light source 22 and the second LED light source 23, it means that the substrate 21 is Figure 2 Status shown.

[0082] By adopting such a structure, the heat treatment device 20 can reduce the following situation: the light from one of the first LED light source 22 and the second LED light source 23 is irradiated to the other LED light source, and the heat generated thereby causes the degradation of the other LED light source. In addition, the heat treatment device 20 only emits the first LED light source 22 and the second LED light source 23 during the heat treatment, thereby achieving a longer life of the first LED light source 22 and the second LED light source 23 while reducing the power consumption of the heat treatment device 20.

[0083] In addition, the conventionally used ultraviolet lamps are difficult to switch on and off within 60 seconds, and the light emission needs about 1 hour to be stable. On the other hand, in the present embodiment, the first LED light source 22 and the second LED light source 23 can be easily switched on and off at high speed, and the light emission is also stable at the same time, so the heat treatment device 20 can improve the productivity of the magnetic recording medium 10 with good bonding force of the protective film layer 13 and the lubricant layer 14 by using the first LED light source 22 and the second LED light source 23.

[0084] The above embodiments are described, but the above embodiments are given as examples, and the present invention is not limited by the above embodiments. The above embodiments can be implemented in various other forms, and various combinations, omissions, substitutions, changes, etc. can be made without departing from the scope of the gist of the invention. These embodiments and their variations belong to the scope and gist of the invention, and also belong to the invention recorded in the patent claims and their equivalents.

[0085] [Description of Reference Numerals]

[0086] 10 Magnetic Recording Media

[0087] 11 Non-magnetic substrate

[0088] 12 Magnetic layer

[0089] 13 Protective film layer

[0090] 14 Lubricant layer

[0091] 20 Heat treatment device

[0092] 21 substrate

[0093] 22First LED light source

[0094] 23 Second LED light source

[0095] 24 Support components

[0096] 25 Institutions

[0097] 30 LED light source

[0098] 32 LED components

Claims

1. A method for manufacturing a magnetic recording medium, comprising: laminating at least a magnetic layer, a protective film layer and a lubricant layer in sequence on a non-magnetic substrate; The surface of the lubricant layer is heated by light from an LED light source. 2 . The method for manufacturing a magnetic recording medium according to claim 1 , wherein the central wavelength of the light emitted from the LED light source is less than 500 nm, and the central wavelength does not include a wavelength range of 170 nm to 190 nm. 3 . The method for producing a magnetic recording medium according to claim 1 , wherein the heat treatment is performed at a pressure close to atmospheric pressure. 4 . The method for producing a magnetic recording medium according to claim 1 , wherein the heat treatment is performed in an air atmosphere. 5 . The method for producing a magnetic recording medium according to claim 1 , wherein the heat treatment is performed for no longer than 60 seconds.

6. A heat treatment device used in the method for manufacturing a magnetic recording medium according to claim 1, comprising: a first LED light source that emits light to one side of the substrate to heat the substrate; a second LED light source that emits light to the other side of the substrate to heat the substrate, and A mechanism in which the outer peripheral end of the substrate is supported by a supporting member so that the substrate can be inserted and removed between the first LED light source and the second LED light source. 7 . The heat treatment apparatus according to claim 6 , wherein more than 50% of the light from the first LED light source and more than 50% of the light from the second LED light source are directly irradiated onto the substrate. 8 . The heat treatment device according to claim 6 , wherein the distance between the first LED light source and the second LED light source and the substrate is less than 50 mm. 9 . The heat treatment device according to claim 6 , wherein the central wavelength of the light emitted from the first LED light source and the second LED light source is less than 500 nm, and the central wavelength does not include a wavelength range of 170 nm to 190 nm. 10 . The heat treatment device according to claim 6 , further comprising a control device configured to cause the first LED light source and the second LED light source to emit light only when the substrate is disposed between the first LED light source and the second LED light source.

Images