Heat treatment apparatus
09759488 · 2017-09-12
Assignee
Inventors
Cpc classification
F27B9/36
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F27B9/145
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F26B13/10
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F27B9/28
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
International classification
F27B9/28
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
C23C14/56
CHEMISTRY; METALLURGY
C23C14/54
CHEMISTRY; METALLURGY
F27B9/36
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F27B9/14
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
Abstract
A heat treatment apparatus includes: a plurality of rollers guiding a substrate, each of the rollers having a roller width greater than a substrate width; a heater including a heating surface which has a width greater than the substrate width; and a heat shield member arranged between a heating surface exposed portion of the heating surface, which is exposed while protruding from an end of the substrate in a width direction of the substrate along the width direction and a roller exposed portion of the specific roller included in the plurality of rollers, the roller exposed portion being exposed while protruding from the end of the substrate in the width direction to the same direction in which the heating surface exposed portion protrudes, the heat shield member shielding heat radiation from the heating surface exposed portion to an outer circumferential surface of the roller exposed portion.
Claims
1. A heat treatment apparatus for performing a heat treatment of a substrate by heating the substrate while feeding the substrate in a longitudinal direction of the substrate, the substrate having a strip shape which extends in the longitudinal direction and a specific substrate width, the heat treatment apparatus comprising: a plurality of rollers guiding the substrate to be fed along a predetermine pathway, each of the rollers including an outer circumferential surface which is contactable with the substrate and a roller width which is greater than the specific substrate width; a heater including a heating surface which has a width greater than the specific substrate width, the heater being arranged so that the heating surface faces a surface of the substrate fed along the pathway, the heater heating the substrate by heating from the heating surface; and a heat shield member inhibiting the outer circumferential surface of the specific roller included in the plurality of rollers from being heated by heat radiation from the heating surface, the heat shield member being arranged between a heating surface exposed portion of the heating surface, which is exposed while protruding from an end of the substrate in a width direction of the substrate along the width direction and a roller exposed portion of the specific roller, which is exposed while protruding from the end of the substrate in the width direction to the same direction in which the heating surface exposed portion protrudes, the heat shield member being shaped to shield the heat radiation from the heating surface exposed portion to the outer circumferential surface of the roller exposed portion.
2. The heat treatment apparatus according to claim 1, further comprising a chamber surrounding a heat treatment space to house the plurality of rollers and the heater in the heat treatment space, the chamber including a heat shield member holding portion which holds the heat shield member so that the heat shield member is detachable.
3. The heat treatment apparatus according to claim 1, wherein the heat shield member is a heat shield panel which is arranged along a heating face of the heating surface exposed portion so as to face the heating face and cover the heating face.
4. The heat treatment apparatus according to claim 1, wherein the plurality of rollers includes a plurality of upper rollers which are arranged at intervals in a predetermined horizontal moving direction and a plurality of lower rollers which are arranged in a position lower than the upper rollers and at intervals in the moving direction, and wherein the heater is a plate heater arranged in a vertically standing manner between portions of the substrate, which are fed in an up and down direction between the upper rollers and lower rollers and which are provided adjacent to each other in the moving direction.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12)
(13)
(14)
(15)
DESCRIPTION OF THE PREFERRED EMBODIMENTS
(16) Hereinafter, preferred embodiments of the present invention will be described by referring to the drawings. In addition, an example of a heat treatment apparatus to which the present invention is applied includes a degassing apparatus, but the present invention is not limited to the degassing apparatus. The present invention can be applied to other heat treatments, for example, to a heat shrinking apparatus by which a substrate formed of a plastic film is heated to be shrunk and deformed.
(17)
(18) The substrate 10 is of a stripped shape having a longitudinal direction. The degassing apparatus performs the degassing treatment by heating the substrate 10 while feeding the substrate 10 in the longitudinal direction. Such degassing treatment is, for example, a treatment in which the substrate 10 is heated to thereby separate oligomer or moisture contained in the substrate 10 therefrom as gas. Materials of the substrate 10 are not limited. The substrate 10 may be formed of, for example, a film of plastic such as PET (Polyethylene Terephthalate), or a metallic foil such as an aluminum foil or an SUS (stainless steel) foil.
(19) As shown in
(20) The substrate supply portion 12 includes a substrate supply roller 22 and a guide roller 24 at downstream of the substrate supply roller 22. The substrate supply roller 22 is configured by a roller shaft 26 and the pre-degassed substrate 10 rolled around the roller shaft 26. The substrate supply roller 22 rolls out the pre-degassed substrate 10 along with rotation of the roller shaft 26.
(21) The degassing portion 14 includes plural guide rollers and plural heaters. The plural guide rollers are arranged so as to guide the substrate 10 to be fed along a predetermined pathway. The plural heaters are arranged so as to heat a surface of the substrate 10 fed along the pathway, by heat radiation. Details of the degassing portion 14 will be described below.
(22) The substrate collecting portion 16 includes a substrate collecting roller 28 and a guide roller 30 at upstream of the substrate collecting roller 28. The substrate collecting roller 28 is configured by a roller shaft 32 and the degassed substrate 10 rolled around the roller shaft 32. The substrate collecting roller 28 rolls up the degassed substrate 10 around the roller shaft 32 along with rotation of the roller shaft 32.
(23) The tension adjustment portion 18 includes a drive roller 34, tension detection rollers 36, 38 respectively arranged at upstream and downstream of the drive roller 34, a motor (not shown) connected to the drive roller 34, and a controller (not shown). The tension detection rollers 36, 38 detect tensions of the substrate 10 at upstream and downstream of the drive roller 34, respectively. The motor drives the drive roller 34 to rotate the drive roller 34 in a direction indicated by arrows in
(24) In the present invention, a concrete configuration of each portion other than the degassing portion 14 will not be limited. For example, the substrate supply portion 12 or the substrate collecting portion 16 may be arranged at a section outside the vacuum chamber 20.
(25) As shown in
(26) The vacuum flange 40 holds one end portion of a component included in each of the substrate supply portion 12, the degassing portion 14, the substrate collecting portion 16, and the tension adjustment portion 18 and supports the component via the single end portion. The other end portion of the component is connected to a common support flange 44 which is shown in
(27) The chamber body 42 includes a cylindrical circumferential wall 46 surrounding the substrate supply portion 12, the degassing portion 14, the substrate collecting portion 16, and the tension adjustment portion 18 as shown in
(28) Furthermore, a roller shaft of each of the rollers other than the roller shafts 26, 32 is not shown in
(29) Next, the details of the degassing portion 14 will be explained with reference to
(30) In the first embodiment, as shown in
(31) Each of the rollers 54 to 58 includes a cylindrical outer circumferential surface 60. A roller support shaft 62 protrudes further outward from both ends of each roller 54 to 58 in the width direction thereof (in the right to left direction in
(32) With respect to the rollers 54 to 58, the substrate 10 is hung over a lower portion of the outer circumferential surface 60 of each of the lower rollers 54, 56, 58 and an upper portion of the outer circumferential surface 60 of each of the upper rollers 55, 57 in a zig-zag manner so as to be alternatively in contact with the lower portion and the upper portion, respectively. Therefore, a feeding force along the longitudinal direction of the substrate 10 is applied thereto; thereby, each of the rollers 54 to 58 guides the substrate 10 while rotating so that the substrate 10 is fed in the up to down direction while moving in the right to left direction (i.e., so that the substrate 10 is moved in a meandering manner).
(33) In the first embodiment, the plural heaters included in the degassing portion 14 include plate heaters 65, 66. Each of the plate heaters 65, 66 having a flat plated shape is arranged in a position to effectively heat the substrate 10 by its own heat generation and heat radiation. Specifically, the substrate 10 hung over the rollers 54 to 58 so as to be fed in the up to down direction as described above includes plural vertical portions 11 arranged in the moving direction (four vertical portions in total in the first embodiment). The plate heaters 65, 66 are each arranged between the vertical portions 11 positioned at both sides of each upper roller 55, 57 in the right to left direction in
(34) Each of the plate heaters 65, 66 includes a heater body of a rectangular shape and a frame body 67 surrounding an outer periphery of the heater body. The frame body 67 has heat insulation properties. The heater body includes a front and back pair of heating surfaces 68A, 68B, and the heating surfaces 68A, 68B are exposed in an area at an inner side of the frame body 67. Each plate heater 65, 66 is arranged in such that the heating surfaces 68A, 68B respectively face surfaces of the vertically extending portions 11 of the substrate 10, and the vertically extending portions 11 are heated by the heat radiation from the heating surfaces 68A, 68B to the vertically extending portions 11.
(35) The degassing apparatus further includes plural heat shield panels 70 each serving as a heat shield member. The heat shield panel 70 inhibits a temperature rising of a specific one of the rollers 54 to 58 due to the heat radiation from each of the plate heaters 65, 66 to the specific roller and thereby serve to inhibit the substrate 10 from being thermally damaged by the temperature rising.
(36) Before explaining the heat shield panels 70, reasons of the occurrence of heating by the heat radiation from the heating surfaces 68A, 68B of each of the plate heaters 65, 66 to the specific roller will be described with reference to the configuration illustrated in
(37) Heating by the heat radiation from the heating surfaces 68A, 68B to each of the rollers 54 to 58 is caused by the followings: 1) exposure of each roller 54 to 58 protruding from the substrate; 2) exposure of the heating surfaces 68A, 68B of each plate heater 65, 66, which protrude from the substrate; and 3) heat radiation between the exposed portions.
(38) 1) Exposure of Each Roller 54 to 58 Protruding from the Substrate
(39) The degassing apparatus is adapted to treatments of plural types of substrates having different widths (dimensions in a direction perpendicular to the longitudinal direction), therefore being designed to be suitable for one of the substrates, which has the largest width. Specifically, a roller width Wr (an axial dimension shown in
(40) Accordingly, in a case where the substrate 10 having a substrate width WO shown in
W1=(Wr−WO)/2
(41) As indicated in the formula, the greater a difference between the roller width Wr and the substrate width WO is, the greater the width W1 of each of the roller exposed portions 59 is. For example, in an apparatus in which a roller width of each roller 54 to 58 is set at 1400 mm so that a substrate having the largest width of 1340 mm can be treated, in a case where the substrate width WO of the substrate 10 to be actually treated is 1000 mm, the roller exposed portions 59 each having the width W1 of 200 mm are generated at both outer sides of the substrate 10 in the width direction thereof.
(42) 2) Exposure of the Heating Surfaces 68A, 68B of Each Plate Heater 65, 66, which Protrude from the Substrate
(43) A width Wh of the heating surface 68A, 68B of each of the plate heaters 65, 66 shown in
(44) Therefore, in a case where the substrate 10 having the substrate width WO (smaller than the largest width) is hung over the intermediate portion of each roller 54 to 58 in the width direction as described above, both end portions of the heating surface 68A, 68B in the width direction thereof largely protrude outward from the both ends of the substrate 10 in the width direction thereof in the same way as the outer circumferential surface 60 of the roller. Portions of the heating surface 68A, 68B, which are exposed while not being covered by the substrate 10 as described above, i.e., heating surface exposed portions 69 each has a width W2, and the width W2 is indicated by the following formula.
W2=(Wh−WO)/2
(45) As indicated in the formula, the greater a difference between the width Wh of the heating surface 68A, 68B and the substrate width WO is, the greater the width W2 of each of the heating surface exposed portions 69 is. For example, in an apparatus in which a width of the heating surface 68A, 68B is set at 1400 mm so that a substrate having the largest width of 1340 mm can be treated, in a case where the substrate width WO of the substrate 10 to be actually treated is 1000 mm, the heating surface exposed portions 69 each having the width W2 of 200 mm are generated at the both outer sides of the substrate 10 in the width direction thereof.
(46) 3) Heat Radiation Between the Exposed Portions
(47) As described above, each roller 54 to 58 and the heating surface 68A, 68B respectively include exposed portions which are exposed from the substrate 10 while not being covered by the substrate 10, i.e., the roller exposed portion 59 and the heating surface exposed portion 69. Therefore, a direct heat radiation from the heating surface exposed portion 69 to the outer circumferential surface 60 of the roller exposed portion 59 may occur. For example, as shown in
(48) Such heating may not only cause a raise in temperature of a portion of the outer circumferential surface 60 of the upper roller 57, which is exposed at the outer side of the substrate 10, but also cause by heat transfer on the upper roller 57, a rise in temperature of a portion of the outer circumferential surface 60 of the upper roller 57, which makes contact with the substrate 10, and further a rise in temperature of the substrate 10. Furthermore, a temperature of the heating surface 68A, 68B is generally set higher (for example, 200 degrees Celsius) than a target heating temperature (for example, 150 degrees Celsius) of the substrate 10. Accordingly, the temperature of the upper roller 57 and the temperature of the substrate 10 making in contact with the upper roller 57 may be increased by the heat radiation to the roller exposed portion 59 to be higher than the target heating temperature. Thus, when the temperature of the substrate 10 reaches a heat resistant limit thereof, the substrate 10 may be thermally damaged. Heating of the roller exposed portion by such heat radiation may be remarkably generated similarly by other heat radiations from the heating surface 68B of the plate heater 65 to the lower roller 58 and from the heating surface 68A of the plate heater 66 to the upper roller 55 and the lower roller 54.
(49) Each of the heat shield panels 70 is used when the substrate 10 having the substrate width WO is treated. The heat shield panels 70 are respectively arranged so as to shield the heat radiations which may be generated as described above when the substrate 10 is treated and so as to inhibit the temperature rising of each roller due to the heat radiations. Specifically, the heat shield panels 70 according to the first embodiment are arranged at both outer sides of the respective vertical portions 11 in the width direction of the substrate 10 having the substrate width WO, and each of the heat shield panels 70 has a shape which covers an entire area of the heating surface exposed portion 69 of the heating surface 68A, 68B of each of the plate heaters 65, 66 in the up and down direction thereof.
(50) Specifically, as shown in
(51) The heat shield panel 70 may be formed by a material which effectively shields the heat radiation from the heating surface exposed portion 69 to the roller exposed portion 59, and the material may be selected within such extent as appropriate. Specifically, it is preferable that the material includes a laminated structure formed by plural thin plates. In view of easiness of handling the heat shield panel 70 and inhibition of a temperature rising of the heat shield panel 70, the thin plate is preferably made of a lightweight material superior in heat dissipation, such as a material made of aluminum or aluminum alloy. Alternatively, the heat shield panel 70 may be cooled, for example, by water or the like.
(52) A dimension of each of the heat shield panels 70 in the up and down direction is desirably established to shield the heat radiation from the target heating surface exposed portion to the roller exposed portion over the whole area in the up and down direction. Alternatively, the dimension of the heat shield panel 70 in the up and down direction may be established to only partially shield the heat radiation. The greater the shielding degree for the heat radiation is, the more remarkably a temperature rising of the target roller exposed portion is inhibited; therefore, the substrate is further surely inhibited from being thermally damaged.
(53) In addition, according to the same idea as above, a portion of the heat shield panels 70 illustrated in
(54) The arrangement, the shape, or the like of each of the heat shield panels 70 may be modified as appropriate as long as the heat shield panel 70 can shield the heat radiation. For example, as shown in
(55) The vacuum chamber 20 includes plural heat shield panel holding portions (each serving as a heat shield member holding portion) which hold the heat shield panels 70 so that the heat shield panels 70 are respectively detachable. As shown in
(56) With the heat shield panel holding portion, each heat shield panel 70 is inserted from above between the holding portions 77, 78 of the corresponding heat shield panel double-supporting member 76 in a state where as shown in
(57) Such attachment and removal of the heat shield panel 70 enable substrates having different widths from one another to be successfully treated by the same degassing apparatus. Specifically, in the event of treating the substrate 10 having the substrate width WO, the heat shield panel 70 is held by the heat shield panel holding portion as described above; thereby, the heat radiation from the heating surface exposed portion 69 of the plate heater 65, 66 to the roller exposed portion 59 of the specific roller is shielded and a temperature rising of the specific roller can be inhibited. Meanwhile, the heat shield panel 70 is removed from the heat shield panel holding portion; thereby, a substrate 10L having a substrate width W3 (for example, the largest width) greater than the substrate width WO, for example, as indicated by two-dot chain lines in
(58) Further, the present invention may be provided with plural types of heat shield members depending on plural types of substrate widths. For example, in order to treat a substrate having a substrate width greater than the substrate width WO shown in
(59) The heat shield panel holding portion for supporting the heat shield panel 70 so that the heat shield panel 70 is detachable as described above is not limited to the configuration allowing the heat shield panel 70 to be inserted from above as described above. The concrete configuration of the heat shield panel holding portion can be designed as appropriate depending on a structure of a chamber which includes the heat shield panel holding portion. Such example will be shown as a second embodiment of the present invention in
(60) The degassing apparatus according to the second embodiment includes a vacuum chamber 80 as a chamber of the apparatus, and the vacuum chamber 80 is formed of a substantially cuboid-shaped box. The vacuum chamber 80 includes a ceiling wall, a bottom wall, and plural side walls, and the plural side walls include a front surface wall 81, a rear surface wall 82, and right and left side surface walls 84. The vacuum chamber 80 houses a degassing portion which is the same as the degassing portion 14 according to the first embodiment. That is, the degassing portion includes plural rollers 86 arranged separately at upper and lower sides and plural plate heaters 88. The front surface wall 81 and the rear surface wall 82 support both end portions of each of the rollers 86 via bearings so that the roller 86 is rotatable, and the front surface wall 81 and the rear surface wall 82 support both end portions of each of the plate heaters 88 in the width direction thereof.
(61) Openings 90 allowing the plural rollers 86 and the plural plate heaters 88 to be opened to the outside along an axial direction of the rollers 88 are formed in the front surface wall 81 and the rear surface wall 82, respectively. Likewise, openings 92 allowing the degassing portion to be opened to the outside in the right and left direction are formed in the right and left side surface walls 84. Further, doors 93 and doors 94 for opening and closing the openings 90 and the openings 92, respectively are formed in the walls 81, 82 and the walls 84 so as to rotate via hinges. The doors 93 and the doors 94 close the openings 90 and the openings 92, thereby sealing a degassing space within the vacuum chamber 80. Meanwhile, the doors 93 and the doors 94 open the openings 90 and the openings 92, thereby enabling an operation such as maintenance through the openings 90 and the openings 92.
(62) The vacuum chamber 80 configured as described above can also hold a heat shield panel 70, which is the same as the heat shield panel 70 according to the first embodiment, so that the heat shield panel 70 is detachable. Thus, it is preferable that the vacuum chamber 80 is configured to include a pair of lower and upper heat shield panel double-supporting portions 96, 98. The heat shield panel double-supporting portions 96, 98 are provided in appropriate positions in the up and down direction so as to be fixed to the front surface wall 81 and the rear surface wall 82, thereby holding the corresponding heat shield panel 70 from above and below. Such configuration allows the heat shield panel 70 to be horizontally inserted through the openings 90 or the opening 92 and attached between the heat shield panel double-supporting portions 96, 98. The heat shield panel 70 inserted can be fixed by a bolt or the like to at least one of the heat shield panel double-supporting portions 96, 98.
(63) On the other hand, it is not necessarily required that the heat shield member according to the present invention is detachable. For example, in an apparatus which treats only a substrate having a predetermined substrate width, attachment and removal of the heat shield member is not necessarily required. Even in such case, each roller and a heating surface of a heater have a roller exposed portion and a heating surface exposed portion, respectively, when a roller width of the roller is designed to be greater than the substrate width in order to surely feed the substrate and when a width of the heating surface of the heater is designed to be greater than the substrate width in order to inhibit the substrate from being unevenly heated. Therefore, the heat shield member is arranged so as to shield heat radiation from the heating surface exposed portion to the roller exposed portion; thereby, a temperature rising of the roller due to the heat radiation can be inhibited.
(64) The present invention does not restrict the concrete shape and arrangement of the heat shield member. For example, the heat shield member according to the present invention is not limited to the heat shield panel 70 that covers the heating surface exposed portion 69 as described above. The heat shield member of the present invention may be a member provided between a heating surface exposed portion and a roller exposed portion so as to shield heat radiation from the heating surface exposed portion to the roller exposed portion. Alternatively, for example, the heat shield member of the present invention may have a cylindrical shape so as to cover an outer circumferential surface of the roller exposed portion from the outside thereof. Such example is shown as a third embodiment of the present invention in
(65) The degassing apparatus according to the third embodiment includes plural cylindrical heat shield members 100 instead of the heat shield panel 70 in the degassing apparatus according to the first embodiment. Each of the heat shield members 100 has a shape which covers the roller exposed portion 59 of each of the rollers 54 to 58. The heat shield member 100 is detachably fixed to the roller support shaft 62 integrally rotating with each roller 54 to 58. In particular, each heat shield member 100 includes a roller fixing portion 102, a heat shield portion 104, and a connecting portion 106. The roller fixing portion 102 is of a cylindrical shape having a small diameter and fixed onto an outer circumferential surface of the roller support shaft 62. The heat shield portion 104 is of a cylindrical shape having an inner diameter greater than an outer diameter of the roller exposed portion 59 so as to cover a radially outward side of the roller exposed portion 59. The connecting portion 106 is of an annular plate shape which is positioned at the outer side of each roller 54 to 58 in the width direction thereof so as to be radially connected to the roller fixing portion 102 and the heat shield portion 104.
(66) The heat shield members 100 can also inhibit roller exposed portions of rollers to which the heat shield members 100 are to be attached from being heated by heat radiation from a specific heating surface exposed portion. In addition, each heat shield member 100 is circumferentially split, for example, into a halved configuration. Therefore, the heat shield member 100 can be attached to and removed from each roller 54 to 58 in a state where each roller 54 to 58 is supported by a chamber, i.e., in a state where each roller 54 to 58 is not removed from the chamber.
(67) Compared with the heat shield member 100 according to the third embodiment, the heat shield panel 70 according to the first embodiment has advantages of being simply shaped to shield heat radiation and of being easily arranged. In particular, the heat shield panel 70 is different from the heat shield member 100 arranged adjacent to the outer circumferential surface 60 of the roller exposed portion 59 and may not make contact with the outer circumferential surface 60 at the time of setting the heat shield panel 70. Therefore, the heat shield panel 70 can be more easily arranged in a predetermined position than the heat shield member 100.
(68) The present invention does not restrict the concrete configuration and arrangement of plural rollers and a heater. For example, the plural rollers may be arranged so as to feed a substrate in a meandering manner, but not limited to such arrangement. The plural rollers may be variously arranged depending on pathways for feeding desired substrates. In addition, the heater may be configured so that both surfaces of a plate-shaped heater body form heating surfaces as with the plate heater 65, 66, but not limited to such configuration. Alternatively, the heater may include a single heating surface.
(69) Such example is shown as a fourth embodiment of the present invention in
(70) In the degassing apparatus of the fourth embodiment, in a case where the heater 116 needs to be arranged above the horizontally extending portion 13 of the substrate 10, i.e., in a case where the heating surface 118 of the heater 116 needs to be arranged so as to face downward, for convenience of the layout of the degassing apparatus, heating surface exposed portions of the heating surface 118, which protrude outward from ends of the substrate 10 in the width direction thereof, may heat roller exposed portions of the lower rollers 111, 114, which protrude outward from the ends of the substrate 10 in the width direction thereof, by heat radiation. In such case, a heat shield member for shielding the heat radiation from the heating surface exposed portions to the roller exposed portions, for example, a heat shield panel 120 positioned at a lower side of the heating surface 118 to cover the heating surface exposed portions of the heating surface 118 is provided as shown in
(71) The present invention includes the foregoing fourth embodiment while being especially effective in a case where as in the first embodiment, the plural upper and lower rollers that move the substrate in a meandering manner are combined with the plate heater that is arranged to face the vertically extending portion of the substrate. In such type of the degassing apparatus, the foregoing combination enables the degassing treatment of the substrate to be effectively performed by a compact configuration. On the other hand, according to the present invention, the upper rollers and the lower rollers are provided closely to one another in the moving direction, and a distance between the heating surface exposed portion of the heater axially protruding from the substrate and the roller exposed portion of the corresponding specific roller to the heating surface exposed portion is small. Therefore, in a case where the outer circumferential surface of the roller exposed portion is heated by heat radiation from the heating surface exposed portion, a temperature of the roller exposed portion remarkably increases. The heat shield member according to the present invention is applied to the degassing apparatus of the foregoing type; thereby, the temperature of the specific roller can be effectively inhibited from increasing regardless of whether each of the rollers and the plate heater are provided closely.