JP2013074226A - Light irradiation module and printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light irradiation device which is not easily affected by heat radiated from ultraviolet light emitting elements even when the mounting density of the ultraviolet light emitting elements becomes relatively high and realizes relatively high ultraviolet irradiation energy.SOLUTION: A light irradiation module has: a light irradiation device where light emitting elements are disposed on one main surface of a substrate; and a plate like heat radiation member having a passage, where a coolant for cooling the light irradiation device flows, therein. The heat radiation member has an opening of the passage on a main surface positioned at the light irradiation device, and the substrate of the light irradiation device is disposed so that the opening of the heat radiation member is covered by the other main surface. A distance between the main surface of the heat radiation member and the other main surface of the substrate becomes longer at a center part of the substrate relative to an outer peripheral part of the substrate.

Description

  The present invention relates to a light irradiation module and a printing apparatus used for curing an ultraviolet curable resin or a paint.

  2. Description of the Related Art Conventionally, ultraviolet irradiation apparatuses are widely used for the purpose of fluorescence reaction observation in medical and bio fields, sterilization applications, adhesion of electronic components, curing of ultraviolet curable resins and inks, and the like. A high-pressure mercury lamp is used as a lamp light source for UV irradiation devices used for curing UV curable resins used for bonding small parts in the field of electronic components, etc., and UV curable ink used for printing. And metal halide lamps are used.

  In recent years, there has been a strong desire to reduce the global environmental load on a global scale, and there has been an active movement to adopt an ultraviolet light emitting element as a lamp light source capable of suppressing the generation of ozone with a relatively long life, energy saving. .

  However, since the illuminance of the ultraviolet light emitting element is relatively low, for example, as described in Patent Document 1, a device in which a plurality of light emitting elements are mounted on one substrate is prepared, and the plurality of devices are mounted on a support. The module of the structure is generally used, and the ultraviolet irradiation energy necessary for the effect of the ultraviolet curable ink is secured.

  However, there is an increasing demand for improvement in ultraviolet irradiation energy, and attempts have been made to increase the mounting density of the ultraviolet light emitting elements. However, although the heat generation from the ultraviolet light emitting elements is relatively small, A device with a higher mounting density has a problem that heat radiation cannot be sufficiently performed, which hinders improvement of ultraviolet irradiation energy.

JP 2008-244165 A

  The present invention has been made in view of the above problems, and realizes relatively high UV irradiation energy by efficiently dissipating the heat generated from the UV light emitting elements even if the mounting density of the UV light emitting elements is relatively high. An object of the present invention is to provide a light irradiation device, a module, and a printing apparatus.

  A light irradiation module according to the present invention has a light irradiation device in which a light emitting element is disposed on one main surface of a substrate, and a flat plate-shaped heat dissipation device having a flow path through which a coolant for cooling the light irradiation device can flow. The heat radiation member has an opening of the flow path on a main surface located on the light irradiation device side, and the substrate of the light irradiation device has the opening of the heat radiation member. The distance between the main surface of the heat dissipating member and the other main surface of the substrate is longer at the center than the outer edge portion of the substrate. .

  The opening has a first opening located on the supply side of the flow path and a second opening located on the discharge side of the flow path.

  Further, the second opening is arranged at a position where the distance from the position corresponding to the center of the substrate is shorter than that of the first opening.

  Further, the first opening is disposed so as to surround the second opening.

  Furthermore, the present invention also provides a printing apparatus comprising printing means for printing on a recording medium, and the above-described light irradiation module for irradiating the printed recording medium with light.

  According to the light irradiation module of the present invention, a flat plate heat dissipation device having a light irradiation device in which a light emitting element is disposed on one main surface of a substrate and a flow path through which a coolant for cooling the light irradiation device can flow. And the heat radiation member has an opening of the flow path on a main surface located on the light irradiation device side, and the substrate of the light irradiation device is formed of the heat radiation member. It arrange | positions so that opening may be covered with the other main surface, and the distance of the said main surface of the said heat radiating member and the other main surface of the said board | substrate is long in the center part rather than the outer edge part of the said board | substrate. For this reason, it becomes possible to supply a relatively large amount of the refrigerant directly to the central portion of the substrate, which is relatively high in temperature due to the heat generated by the light emitting element, and the heat dissipation of the substrate is maintained high. At the same time, variations in the temperature distribution of the substrate are kept relatively small.

  Therefore, according to the light irradiation device of the present embodiment, even if the mounting density of the ultraviolet light emitting elements is relatively high, it is hardly affected by the heat generated by the ultraviolet light emitting elements themselves and realizes a relatively high ultraviolet irradiation energy. A light irradiation device is realized.

FIG. 1 is a bottom view of a light irradiation module according to an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along line 1I-1I of the light irradiation module shown in FIG. FIG. 3 is a cross-sectional view of the light irradiation module shown in FIG. 1 taken along line 1II-1II. 4 is a top view of a printing apparatus using the light irradiation module shown in FIG. FIG. 5 is a side view of the printing apparatus shown in FIG. FIG. 6 is a cross-sectional view showing a first modification of the light irradiation device shown in FIG. FIG. 7 is a cross-sectional view showing a second modification of the light irradiation device shown in FIG. FIG. 8 is a cross-sectional view showing a third modification of the light irradiation device shown in FIG. Fig.9 (a) is a top view which shows an example of the member for thermal radiation which comprises the light irradiation device shown in FIG. FIG.9 (b) is a top view which shows the other example of the member for thermal radiation which comprises the light irradiation device shown in FIG.

  Hereinafter, the light irradiation module and the printing apparatus of the present invention will be described with reference to the drawings.

  The light irradiation module 1 shown in FIGS. 1 and 2 is incorporated in a printing apparatus such as an offset printing apparatus or an inkjet printing apparatus that uses ultraviolet curable ink, and the object (recording medium) is coated with the ultraviolet curable ink. It functions as an ultraviolet light generation light source of an ultraviolet irradiation module that cures the ultraviolet curable ink by irradiating ultraviolet rays later.

  The light irradiation module 1 includes a light irradiation device 2 and a flat plate-like heat radiating member 100 having therein a flow path 110 through which a coolant for cooling the light irradiation device 2 can flow.

  First, the light irradiation device 2 will be described.

(Light irradiation device)
As shown in FIGS. 2 and 3, the light irradiation device 2 includes a substrate 10 having a plurality of openings 12 on one main surface 11 a, a plurality of connection pads 13 provided in each opening 12, and the substrate 10. A plurality of light emitting elements 20 disposed in each opening 12 and electrically connected to the connection pad 13, and a plurality of sealing materials 30 filled in each opening 12 and covering the light emitting element 20. I have.

  The substrate 10 includes a stacked body 40 in which a first insulating layer 41 and a second insulating layer 42 are stacked, and an electrical wiring 60 that connects the light emitting elements 20 to each other, and is viewed from the main surface 11a side in plan view. Thus, the light emitting element 20 is supported in the opening 12 provided on the one main surface 11a.

  The first insulating layer 41 includes, for example, an aluminum oxide sintered body, an aluminum nitride sintered body, a mullite sintered body, ceramics such as glass ceramics, and resins such as epoxy resins and liquid crystal polymers (LCP). , Etc.

  The other main surface 11 b of the substrate 10 has a recess 11 c so that the center portion is located closer to the one main surface 11 a side of the substrate 10 than the outer edge portion of the substrate 10.

  Next, the electrical wiring 60 is formed in a predetermined pattern using a conductive material such as tungsten (W), molybdenum (Mo), manganese (Mn), copper (Cu), and the like. Alternatively, it functions as a power supply wiring for supplying a current from the light emitting element 20.

  Next, in the second insulating layer 42 laminated on the first insulating layer 41, the opening 12 that penetrates the second insulating layer 42 is formed.

  The opening 12 has an inner peripheral surface 14 inclined so that each opening has a larger opening area on the one main surface 11a side of the substrate 10 than the mounting surface of the light emitting element 20, and when viewed in plan, For example, it has a substantially circular shape. The opening shape is not limited to a circular shape, and may be a substantially rectangular shape.

  Such an opening 12 has a function of reflecting light emitted from the light emitting element 20 upward on the inner peripheral surface 14 to improve light extraction efficiency.

  In order to improve the light extraction efficiency, the material of the second insulating layer 42 is a porous ceramic material having a relatively good reflectivity with respect to light in the ultraviolet region, such as an aluminum oxide sintered body, an oxide It is preferable to form with a zirconium sintered body and an aluminum nitride sintered body. Further, from the viewpoint of improving the light extraction efficiency, a metal reflection film may be provided on the inner peripheral surface 14 of the opening 12.

  Such openings 12 are arranged vertically and horizontally over the entire main surface 11 a of the substrate 10. For example, in this embodiment, they are arranged in a staggered pattern. By arranging in a staggered pattern, the light emitting elements 20 can be arranged with higher density, and the illuminance per unit area can be made relatively high. Here, to arrange in a zigzag pattern is synonymous with arranging at the grid points of the diagonal grid.

  In the light irradiation device 2 of this embodiment, the arrangement shape of the openings 12 is a staggered lattice shape, but it may be a regular lattice shape, and may be arranged in any manner as long as the required illuminance is satisfied.

  Of course, the light outputs of the plurality of light emitting elements 20 of the present embodiment have substantially the same value. For example, the variation of the light output as a whole of the plurality of light emitting elements 20 of the present embodiment is within 10%.

  When the substrate 10 including the laminate 40 including the first insulating layer 41 and the second insulating layer 42 as described above is used, when the first insulating layer 41 and the second insulating layer 42 are made of ceramics or the like, It is manufactured through the following steps. First, a plurality of ceramic green sheets manufactured by a conventionally known method is prepared. A hole corresponding to the opening is formed in the ceramic green sheet corresponding to the opening 12 by a method such as punching. Next, after printing (not shown) a metal paste to be the electric wiring 60 on the green sheet, the green sheet is laminated so that the printed metal paste is positioned between the green sheets. Examples of the metal paste used for the electric wiring 60 include a paste containing a metal such as tungsten (W), molybdenum (Mo), manganese (Mn), and copper (Cu). Next, by firing the laminate, the substrate 10 having the electrical wiring 60 and the opening 12 can be formed by firing the green sheet and the metal paste together. The concave portion 11c may be formed by a press or the like on the surface that becomes the other main surface 11b of the first insulating layer 41 of the green sheet before firing, or a convex weight is placed on the other main surface 11b during firing. It may be formed by grinding, or may be formed by grinding the other main surface 11b after firing.

  Moreover, when the 1st insulating layer 41 and the 2nd insulating layer 42 consist of resin, the following methods can be considered as the manufacturing method of the board | substrate 10, for example. First, a precursor sheet of a thermosetting resin is prepared. Next, a plurality of precursor sheets are laminated so that lead terminals made of a metal material to be the electrical wiring 60 are disposed between the precursor sheets and the lead terminals are embedded in the precursor sheets. Examples of the material for forming the lead terminal include metal materials such as Cu, Ag, Al, iron (Fe) -nickel (Ni) -cobalt (Co) alloy, and Fe-Ni alloy. And after forming the hole corresponding to the opening part 12 in the precursor sheet | seat, and the dent corresponding to the recessed part 11c by methods, such as a laser processing and an etching, the board | substrate 10 is completed by thermosetting this. In addition, when forming a hole and a dent by laser processing, it may be after thermosetting the precursor sheet.

  On the other hand, in the opening 12 of the substrate 10, a connection pad 13 electrically connected to the light emitting element 20 and a bonding material 15 such as solder, gold (Au) wire, aluminum (Al) wire, etc. are connected to the connection pad 13. And the sealing material 30 for sealing the light emitting element 20 are provided.

  The connection pad 13 is formed of a metal layer made of a metal material such as tungsten (W), molybdenum (Mo), manganese (Mn), and copper (Cu). If necessary, a nickel (Ni) layer, a palladium (Pd) layer, a gold (Au) layer, or the like may be further laminated on the metal layer. The connection pad 13 is connected to the light emitting element 20 by a bonding material 15 such as solder, gold (Au) wire, or aluminum (Al) wire.

  The light-emitting element 20 includes, for example, a light-emitting diode in which a p-type semiconductor layer and an n-type semiconductor layer made of a semiconductor material such as GaAs or GaN are stacked on an element substrate 21 such as a sapphire substrate, or a semiconductor layer is organic. An organic EL element made of a material is used.

The light emitting element 20 is connected to a semiconductor layer 22 having a light emitting layer and a connection pad 13 disposed on the substrate 10 through a bonding material 15 such as solder, gold (Au) wire, aluminum (Al) wire, or the like. First element electrodes 23 and 24 made of a metal material such as Ag are provided, and are connected to the substrate 10 by wire bonding. The light emitting element 20 emits light having a predetermined wavelength according to the current flowing between the element electrodes 23 and 24 with predetermined luminance, and emits the light to the outside through the element substrate 21 or directly. As is well known, the element substrate 21 can be omitted. Further, the connection between the element electrodes 23 and 24 of the light emitting element 20 and the connection pad 13 may be performed by a conventionally known flip lip connection technique using solder or the like as the bonding material 15.

  In the present embodiment, an LED that emits UV light having a wavelength spectrum peak of 250 to 395 [nm] or less is employed. That is, in this embodiment, a UV-LED element is employed as the light emitting element 20. The light emitting element 20 is formed by a conventionally known thin film forming technique.

  And this light emitting element 20 is sealed with the sealing material 30 mentioned above.

  The sealing material 30 is formed of an insulating material such as a light-transmitting resin material, and prevents the entry of moisture from the outside by sealing the light emitting element 20 well, or from the outside. The impact is absorbed and the light emitting element 20 is protected.

  The sealing material 30 is a material having a refractive index between the refractive index of the first element substrate 31a constituting the light emitting element 20 (1.7 for sapphire) and the refractive index of air (about 1.0). For example, the light extraction efficiency of the light emitting element 20 can be improved by being formed of, for example, a silicone resin (refractive index: about 1.4).

  The sealing material 30 is formed by mounting the light emitting element 20 on the substrate 10, filling a precursor such as a silicone resin into the opening 12, and curing it.

(Embodiment of light irradiation module)
The light irradiation module 1 shown in FIG. 2 includes a heat radiating member 100 and a light irradiating device 2 disposed on the heat radiating member 100. The light irradiating device 2 is an adhesive 120 such as silicone resin or epoxy resin. Is disposed on the main surface of the heat dissipation member 100.

  The heat dissipation member 100 functions as a support for the light irradiation device 2 and as a heat dissipation body for radiating heat generated by the light irradiation device 2 to the outside. As a material for forming the heat radiating member 100, a material having a high thermal conductivity is preferable. Examples thereof include various metal materials, ceramics, and resin materials. The heat dissipation member 100 of this embodiment is formed of copper.

  A flow path 110 through which a coolant for cooling the light irradiation device 2 can flow is formed inside the heat radiation member 100, and an opening 110a of the flow path 110 is formed on the main surface 100a located on the light irradiation device 2 side. have. And it arrange | positions so that the opening 110a may be covered with the other main surface 11b of the board | substrate 10 of the light irradiation device 2. FIG.

  Thus, by arranging the opening 110a so as to be covered with the other main surface 11b of the substrate 10 of the light irradiation device 2, the refrigerant flowing through the flow path 110 formed inside the heat radiation member 100 is directly irradiated with light. It comes into contact with the device 2, and the heat of the light irradiation device 2 can be radiated relatively efficiently. Moreover, since the other main surface 11b of the substrate 10 has the recess 11c, the amount of refrigerant supplied to the central portion of the light irradiation device 2 that is relatively high in temperature due to the heat generated by the plurality of light emitting elements 20 is relatively small. Since it can be increased, the in-plane temperature variation of the light irradiation device 2 can be made relatively small.

Furthermore, if the light irradiation module 1 is installed with the one main surface 11a of the substrate 10 on which the light emitting element 20 in the light irradiation device 2 is arranged facing the direction of the gravitational field, the temperature of the light irradiation device 2 becomes relatively high. In the central portion, the refrigerant flows in a direction from the other main surface 11 b side of the light irradiation device 2 toward the main surface 100 a side of the heat radiation member 100, and at the outer edge portion of the light irradiation device 2, the refrigerant is the main heat radiation member 100. Thermal convection that flows in the direction from the surface 100a side toward the other main surface 11b side of the light irradiation device 2 is generated, and a relatively efficient refrigerant replacement is performed, so that heat dissipation can be further maintained high. It becomes possible, and the temperature variation in the surface of the light irradiation device 2 can be made relatively small.

  Therefore, according to the light irradiation device 2 of the present embodiment, even if the mounting density of the ultraviolet light emitting elements is relatively high, it is hardly affected by the heat generated by the ultraviolet light emitting elements themselves and realizes a relatively high ultraviolet irradiation energy. A light irradiation device is realized.

(Embodiment of printing apparatus)
As an embodiment of the printing apparatus of the present invention, the printing apparatus 200 shown in FIGS. 4 and 5 will be described as an example. The printing apparatus 200 includes a transport mechanism 210 for transporting the recording medium 250, an inkjet head 220 as a printing mechanism for printing on the transported recording medium 250, and an ultraviolet for the recording medium 250 after printing. The light irradiation module 1 which irradiates light and the control mechanism 230 which controls light emission of the light irradiation module 1 are provided. Here, the recording medium 250 corresponds to the above-described object.

  The transport mechanism 210 is for transporting the recording medium 250 so as to pass through the inkjet head 220 and the light irradiation module 1 in this order. The transport mechanism 210 and the mounting table 211 are arranged to face each other and are rotatably supported. And a roller 212. The recording medium 250 supported by the mounting table 211 is sent between the pair of transport rollers 212, and the transport roller 212 is rotated to send the recording medium 250 in the transport direction.

  The inkjet head 220 has a function of attaching a photosensitive material to the recording medium 250 conveyed via the conveyance mechanism 210. The ink-jet head 220 is configured to eject droplets containing the photosensitive material toward the recording medium 250 and adhere to the recording medium 250. In the present embodiment, ultraviolet curable ink is employed as the photosensitive material. Examples of the photosensitive material include a photosensitive resist and a photocurable resin in addition to the ultraviolet curable ink.

  In the present embodiment, a line-type inkjet head is adopted as the inkjet head 220. The inkjet head 220 has a plurality of ejection holes 220a arranged in a line, and is configured to eject ultraviolet curable ink from the ejection holes 220a. The inkjet head 220 ejects ink from the ejection holes 220a to the recording medium 250 transported in a direction orthogonal to the arrangement of the ejection holes 220a, and deposits the ink on the recording medium, thereby causing the recording medium to adhere to the recording medium. Printing is performed.

  In the present embodiment, a line-type inkjet head has been described as an example of the printing mechanism, but the present invention is not limited to this. For example, a serial-type inkjet head may be employed, A serial type spray head may be employed. Further, as the printing mechanism, an electrostatic head that accumulates static electricity of the recording medium 250 and attaches the photosensitive material with the static electricity may be employed, or the recording medium 250 is immersed in a liquid photosensitive material and the photosensitive medium is used. An immersion apparatus for attaching a conductive material may be employed. Further, a brush, a brush, and a roller may be employed as the printing mechanism.

In the printing apparatus 200, the light irradiation module 1 has a function of exposing the photosensitive material attached to the recording medium 250 conveyed via the conveyance mechanism 210. The light irradiation module 1 is provided on the downstream side in the transport direction with respect to the inkjet head 220. In the printing apparatus 200, the light emitting element 20 and the second light emitting element 30b have a function of exposing the photosensitive material attached to the recording medium 250.

  The control mechanism 230 has a function of controlling light emission of the light irradiation module 1. The memory of the control mechanism 230 stores information indicating light characteristics that make it relatively good to cure the ink droplets ejected from the inkjet head 220. Specific examples of the stored information include wavelength distribution characteristics suitable for curing ejected ink droplets, and numerical values representing emission intensity (emission intensity in each wavelength range). In the printing apparatus 200 of the present embodiment, by including the control mechanism 230, the magnitude of the drive current input to the plurality of light emitting elements 20 can be adjusted based on the stored information of the control mechanism 230. From this, according to the printing apparatus 200, light can be irradiated with an appropriate ultraviolet irradiation energy according to the characteristics of the ink to be used, and the ink droplet can be cured with a relatively low energy light.

  In the printing apparatus 200, the transport mechanism 210 transports the recording medium 250 in the transport direction. The inkjet head 220 discharges ultraviolet curable ink to the recording medium 250 being conveyed, and causes the ultraviolet curable ink to adhere to the surface of the recording medium 250. At this time, the ultraviolet curable ink to be attached to the recording medium 250 may be attached to the entire surface, partially attached, or attached in a desired pattern. In the printing apparatus 200, the ultraviolet curable ink attached to the recording medium 250 is irradiated with ultraviolet rays emitted from the light irradiation module 1 to cure the ultraviolet curable ink.

  In the printing apparatus 200 of the present embodiment, the above-described effects of the light irradiation module 1 can be enjoyed.

  While specific embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications can be made without departing from the spirit of the invention.

  For example, like the 1st modification shown in FIG. 6, you may provide the 1st opening 110b located in the supply side of the flow path 110, and the 2nd opening 110c located in the discharge | emission side. This configuration is preferable because the refrigerant flows from the first opening 110b located on the supply side to the second opening 110c located on the discharge side, so that the refrigerant can be replaced more favorably in the recess 11c. .

  Further, as in the second modification shown in FIG. 7, the first opening 110b located on the supply side of the flow path 110 and the second opening 110c located on the discharge side are provided, and the second opening 110c is the second opening 110c. It is preferable that the distance from the position corresponding to the center of the substrate 10 is shorter than the one opening 110b. In the second modification, the second opening 110 c is disposed at a position corresponding to the center of the substrate 10. By adopting such a configuration, the refrigerant is radiated from the side of the other main surface 11b of the light irradiation device 2 near the center of the light irradiation device 2 where the temperature is relatively high due to heat generated by the plurality of light emitting elements 20. Since the convection is performed in the direction toward the main surface 100a side of 100, the discharge efficiency of the refrigerant in the recess 11c can be increased, and the refrigerant can be replaced in the recess 11c, which is preferable.

Further, as in the third modification shown in FIG. 8, the first opening 110b located on the supply side of the flow path 110 and the second opening 110c located on the discharge side are provided, and surround the second opening 110c. Thus, it is preferable to arrange the first opening 110b. Arranging the first opening 110b so as to surround the second opening 110c is, for example, the first opening 110b integrated so as to surround the outer periphery of the second opening 110c as shown in FIG. Alternatively, as shown in FIG. 9C, the outer periphery of the second opening 100c may be surrounded by a plurality of first openings 110b. By setting it as such a structure, the refrigerant | coolant which flowed into the recessed part 11c from the 1st opening 110b located in a supply side turns into a flow which goes to the center part from the outer edge part of the board | substrate 10, and the center part of the board | substrate 10 is the light irradiation device 2. In order to correspond to the position where the temperature is relatively high, the refrigerant convects in the direction from the other main surface 11b side of the light irradiation device 2 to the main surface 100a side of the heat radiation member 100, whereby the refrigerant in the recess 11c. This is preferable because the replacement of the above is performed satisfactorily.

  In the light irradiation module 1 of the present embodiment, one light irradiation device 2 is disposed on the heat dissipation member 100, but a plurality of light irradiation devices 2 may be arranged vertically and horizontally on the heat dissipation member 100. .

  In order to make the illumination distribution of the light irradiation module 1 uniform, it is preferable that the adjacent light irradiation devices 2 are in close contact with each other.

  Thus, the light irradiation module 1 in which the plurality of light irradiation devices 2 are arranged on the heat radiation member 100 can irradiate the recording medium with a relatively wide ultraviolet ray.

  The embodiment of the printing apparatus 200 is not limited to the above embodiment. For example, a so-called offset printing type printer that rotates a shaft-supported roller and conveys a recording medium along the roller surface may exhibit the same effect.

  In the present embodiment, an example in which the light irradiation module 1 is applied to the printing apparatus 200 using the inkjet head 220 is shown. The light irradiation module 1 cures, for example, a photo-curing resin spin-coated on the surface of the object. It can also be applied to the curing of various types of photo-curing resins such as dedicated devices. Moreover, you may use the light irradiation module 1 for the irradiation light source etc. in an exposure apparatus, for example.

DESCRIPTION OF SYMBOLS 1 Light irradiation module 2 Light irradiation device 10 Board | substrate 11a One main surface 11b The other main surface 11c Recess 12 Opening part 13 Connection pad 14 Inner peripheral surface 15 Joining material 20 Light emitting element 21 Element substrate 22 Semiconductor layer 23, 24 Element electrode 30 Sealing Material 40 Laminate 41 First Insulating Layer 42 Second Insulating Layer 60 Electrical Wiring 100 Heat Dissipating Member 100a Main Surface 110 Channel 110a Opening 110b First Opening 110c Second Opening 120 Adhesive 200 Printing Device 210 Conveying Mechanism 211 Place 212 Transport roller 220 Inkjet head 220a Discharge hole 230 Control mechanism 250 Recording medium

Claims (5)

A light irradiation device having a light emitting element disposed on one main surface of the substrate, and a flat plate-like heat radiating member having a flow path through which a coolant for cooling the light irradiation device can flow,
The heat dissipation member has an opening of the flow path on a main surface located on the light irradiation device side,
The substrate of the light irradiation device is disposed so as to cover the opening of the heat dissipation member with the other main surface,
The light irradiation module, wherein a distance between the main surface of the heat radiating member and the other main surface of the substrate is longer at a central portion than an outer edge portion of the substrate.   2. The light irradiation module according to claim 1, wherein the opening includes a first opening located on a supply side of the flow path and a second opening located on a discharge side of the flow path.   The light irradiation module according to claim 2, wherein the second opening is disposed at a position where a distance from a position corresponding to the center of the substrate is shorter than the first opening.   The light irradiation module according to claim 2, wherein the first opening is disposed so as to surround the second opening. Printing means for printing on a recording medium;
A printing apparatus comprising: the light irradiation module according to claim 1, which irradiates light onto the printed recording medium.

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