JP6617024B2 - Light emitting device - Google Patents

Description

  The present invention relates to a light emitting device.

  One of the light sources of a light emitting device is an organic EL element. The organic EL element has a configuration in which an organic layer is disposed between a first electrode serving as an anode and a second electrode serving as a cathode. Since the organic layer is vulnerable to water and oxygen, it needs to be sealed. For example, Patent Document 1 describes that an organic EL element is covered with a thermoplastic resin layer, and further a metal foil is provided thereon.

Patent Document 2 describes that a sealing portion having a recess is used as a sealing portion that shields the display portion from outside air. In patent document 2, the display part is arrange | positioned in the recessed part. The edge of the sealing portion is fixed to the substrate of the display portion using an adhesive. A planarizing layer is formed between the substrate and the adhesive. The planarization layer is formed using an insulating material such as SiN or SiO ₂ . In Patent Document 2, the purpose of forming the planarization layer is to ensure airtightness. The method for forming a planarization layer in Patent Document 2 is film formation and patterning.

JP 2014-154507 A JP 2005-251630 A

  In the structure described in Patent Document 1, the light emitting portion of the organic EL element is sealed using a resin film and a metal sheet such as a metal foil or a metal film. As a result of investigation by the present inventors, since the resin is more permeable to moisture and oxygen than metal, moisture and oxygen are introduced from the portion of the resin film located on the end surface of the sealing structure into the sealing structure. It has been found that there is a possibility of intrusion and the performance of the sealing structure is improved by suppressing the thickness from the end face of the resin film.

  As a problem to be solved by the present invention, when a light emitting part of an organic EL element is sealed using a resin film and a metal sheet, the resin film is sealed from a portion located on the end surface of the sealing structure. One example is to reduce the amount of moisture and oxygen that enter the structure.

The invention according to claim 1 is a substrate;
A light emitting part formed on the substrate;
A wiring part formed on the substrate and electrically connected to the light emitting part;
A first insulating layer formed on at least a part of the wiring portion;
A resin film covering at least a part of the wiring part and the light emitting part;
A metal sheet located on the resin film and covering at least a part of the wiring part and the light emitting part;
With
The first region which is at least part of the resin film overlapping with the first insulating layer is lighter than the second region of the resin film located between the light emitting portion and the first insulating layer. It is.

It is a top view which shows the structure of the light-emitting device which concerns on embodiment. It is the figure which removed the sealing member and the connection member from FIG. FIG. 3 is a diagram in which a second electrode is removed from FIG. 2. It is the figure which removed the 2nd insulating layer and the organic layer from FIG. It is the figure which removed the 1st wiring part and the electroconductive part from FIG. It is AA sectional drawing of FIG. It is sectional drawing for demonstrating the manufacturing method of a light-emitting device. 6 is a cross-sectional view illustrating a configuration and a manufacturing method of a light emitting device according to Modification 1. FIG. It is sectional drawing which shows the structure of the light-emitting device which concerns on the modification 2, and a manufacturing method.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same reference numerals are given to the same components, and the description will be omitted as appropriate.

(Embodiment)
FIG. 1 is a plan view showing a configuration of a light emitting device 10 according to the embodiment. FIG. 2 is a view in which the sealing member 220 and the connecting members 200 and 202 are removed from FIG. FIG. 3 is a diagram in which the second electrode 130 is removed from FIG. 2. FIG. 4 is a diagram in which the second insulating layer 150 and the organic layer 120 are removed from FIG. 3. FIG. 5 is a diagram in which the first wiring part 114 and the conductive parts 160 and 170 are removed from FIG. 4.

  The light emitting device 10 according to the embodiment includes a substrate 100, a light emitting unit 140, a first wiring unit 114, a first insulating layer 155, a resin film 190, and a metal sheet 180. The light emitting unit 140 is formed on the substrate 100. The first wiring part 114 is formed on the first electrode 110 and is electrically connected to the light emitting part 140. The first insulating layer 155 is formed on at least a part of the first wiring part 114. The resin film 190 covers at least a part of the first wiring part 114 and the light emitting part 140. The metal sheet 180 is located on the resin film 190 and covers at least a part of the first wiring part 114 and the light emitting part 140. In addition, at least a part of the resin film 190 overlapping with the first insulating layer 155 (hereinafter referred to as a first region 192) is a region of the resin film 190 between the light emitting unit 140 and the first insulating layer 155. It is thinner than the region located above (hereinafter referred to as second region 194). Hereinafter, the light emitting device 10 will be described in detail.

  In the example shown in FIGS. 1 to 5, the light emitting device 10 is a lighting device. However, the light emitting device 10 may be a display. The light emitting device 10 may be a bottom emission type light emitting device or a top emission type light emitting device. The light emitting device 10 is formed using a substrate 100.

When the light emitting device 10 is a bottom emission type, the substrate 100 is formed of a light transmissive material such as glass or a light transmissive resin. On the other hand, when the light emitting device 10 is a top emission type, the substrate 100 may be formed of the above-described translucent material or may be formed of a material that does not have translucency. The substrate 100 is, for example, a polygon such as a rectangle. Further, the substrate 100 may have flexibility. In the case where the substrate 100 has flexibility, the thickness of the substrate 100 is, for example, not less than 10 μm and not more than 1000 μm. In particular, when the substrate 100 is made of a glass material and has flexibility, the thickness of the substrate 100 is, for example, 200 μm or less. In the case where the substrate 100 is made of a resin material and is flexible, the material of the substrate 100 includes, for example, PEN (polyethylene naphthalate), PES (polyethersulfone), PET (polyethylene terephthalate), or polyimide. Is formed. In the case where the substrate 100 includes a resin material, an inorganic barrier film such as SiN _x or SiON is formed on at least the light emitting surface (preferably both surfaces) of the substrate 100 in order to suppress moisture from passing through the substrate 100. ing.

  A light emitting unit 140 is formed on the substrate 100. The light emitting unit 140 is an organic EL element, and includes a first electrode 110, an organic layer 120, and a second electrode 130. The organic layer 120 is located between the first electrode 110 and the second electrode 130.

  At least one of the first electrode 110 and the second electrode 130 is a transparent electrode having optical transparency. For example, when the light emitting device 10 is a bottom emission type light emitting device, at least the first electrode 110 is a transparent electrode. On the other hand, when the light emitting device 10 is a top emission type light emitting device, at least the second electrode 130 is a transparent electrode. Note that both the first electrode 110 and the second electrode 130 may be transparent electrodes.

  The transparent conductive material constituting the transparent electrode is a metal-containing material, for example, a metal oxide such as ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), IWZO (Indium Tungsten Zinc Oxide), or ZnO (Zinc Oxide). is there. The thickness of the first electrode 110 is, for example, not less than 10 nm and not more than 500 nm. The first electrode 110 is formed using, for example, a sputtering method or a vapor deposition method (for example, a vacuum vapor deposition method). The first electrode 110 may be a carbon nanotube, a conductive organic material such as PEDOT / PSS, or a thin metal electrode.

  Of the first electrode 110 and the second electrode 130, the non-transparent electrode is selected from, for example, a first group consisting of Al, Au, Ag, Pt, Mg, Sn, Zn, and In. Or a metal layer made of an alloy of metals selected from this first group. This electrode is formed by using, for example, a sputtering method or a vapor deposition method (for example, a vacuum vapor deposition method).

  When the light emitting device 10 is a top emission type light emitting device, the first electrode 110 may have a structure in which a metal layer and a transparent conductive layer are stacked in this order.

  The organic layer 120 has a configuration in which, for example, a hole injection layer, a light emitting layer, and an electron injection layer are stacked in this order. A hole transport layer may be formed between the hole injection layer and the light emitting layer. In addition, an electron transport layer may be formed between the light emitting layer and the electron injection layer. The organic layer 120 may be formed by a vapor deposition method (for example, a vacuum vapor deposition method). In addition, at least one layer of the organic layer 120, for example, a layer in contact with the first electrode may be formed by a coating method such as an inkjet method, a printing method, or a spray method. In this case, the remaining layers of the organic layer 120 are formed by vapor deposition. Moreover, all the layers of the organic layer 120 may be formed using the apply | coating method.

  A conductive portion 116 is formed on the first electrode 110. The conductive portion 116 is formed using a material having a sheet resistance lower than that of the first electrode 110, such as a metal or an alloy, and functions as an auxiliary electrode of the first electrode 110. The conductive portion 116 may be formed using one metal film, or may be formed using a stacked film in which a plurality of metal films are stacked. The conductive part 116 may be, for example, a laminated film in which a Mo alloy, an Al alloy, and a Mo alloy are laminated in this order. Note that a conductive portion 160 and a conductive portion 170 described later also have a cross-sectional structure similar to that of the conductive portion 116. The conductive portion 116 is formed using, for example, a vapor deposition method using a mask (for example, a vacuum vapor deposition method) or a sputtering method. In the example shown in this drawing, a plurality of conductive portions 116 are formed on the first electrode 110. The plurality of conductive portions 116 are parallel to each other.

  In the example shown in FIGS. 1 to 5, the light emitting device 10 has a plurality of stripe-shaped light emitting portions 140. The first electrode 110 and the second electrode 130 are common electrodes of the plurality of light emitting units 140, but the first electrode 110 and the second electrode 130 may be divided for each light emitting unit 140. . Further, the above-described conductive portion 116 is provided in each of the plurality of light emitting portions 140. In addition to the organic layer 120, a second insulating layer 150 is formed between the first electrode 110 and the light emitting unit 140.

  The second insulating layer 150 covers a region other than the light emitting unit 140 in the first electrode 110. In other words, a plurality of rectangular openings 152 are formed in the second insulating layer 150. These openings 152 are provided in order to bring the organic layer 120 into contact with the first electrode 110, and extend in parallel to each other. A portion of the second insulating layer 150 located between the openings 152 overlaps with the conductive portion 116. In other words, the conductive portion 116 is covered with the second insulating layer 150.

  The second insulating layer 150 is made of a photosensitive resin material such as polyimide. The second insulating layer 150 is formed by applying a resin material to be the second insulating layer 150 and then exposing and developing the resin material. This step is performed, for example, after forming the first electrode 110 and the conductive portion 116 and before forming the organic layer 120. In addition, when a part of the organic layer 120 is formed by a coating method, if the second insulating film 150 has liquid repellency, the coating material is repelled by the second insulating film 150 when the organic layer 120 is applied. The For this reason, it is difficult for the coating material of the organic layer 120 to swell at the edge of the second insulating film 150 or at the boundary between the second insulating film 150 and the organic layer 120, and as a result, variation in the thickness of the organic layer 120 can be suppressed.

  The light emitting device 10 has a first terminal 112 and a second terminal 132. The first terminal 112 is electrically connected to the first electrode 110, and the second terminal 132 is electrically connected to the second electrode 130. For example, the first terminal 112 and the second terminal 132 include a layer formed of the same material as that of the first electrode 110.

  A first wiring part 114 is provided between the first terminal 112 and the first electrode 110. The first wiring part 114 is a member that electrically connects the first terminal 112 and the light emitting part 140 (specifically, the first electrode 110). A lead-out wiring may also be provided between the second terminal 132 and the second electrode 130. This lead wiring is referred to as a second wiring part 134. When simply denoted as a wiring part, this wiring part may be either the first wiring part 114 or the second wiring part 134. In the present embodiment, the first terminal 112, the second terminal 132, and the first wiring portion 114 have a layer formed of the same material as the first electrode 110. Of the first terminal 112 and the first wiring part 114, a layer formed of the same material as the first electrode 110 is integrated with the first electrode 110. On the other hand, the layer formed of the same material as the first electrode 110 in the second terminal 132 is separated from the first electrode 110.

  In the example shown in FIGS. 1 to 5, the substrate 100 is rectangular. The first terminal 112 is provided along each of two opposite sides of the four sides of the substrate 100, and the second terminal 132 is provided along each of the remaining two sides of the substrate 100. ing.

  The first terminal 112 and the first wiring part 114 have a conductive part 160, and the second terminal 132 has a conductive part 170. The conductive portions 160 and 170 both extend along different sides of the substrate 100. The conductive portions 160 and 170 are formed of a layer containing the same material as that of the conductive portion 116.

  The connection member 200 is connected to the first terminal 112, and the connection member 202 is connected to the second terminal 132. The connection members 200 and 202 are, for example, REIT wiring or tab wiring. A portion of the connecting member 200 that is connected to the first terminal 112 extends in the same direction (first direction) as the first terminal 112, and the first terminal is interposed via a conductive adhesive layer. 112 is fixed and electrically connected. A portion of the connecting member 202 connected to the second terminal 132 extends in the same direction as the second terminal 132 (a direction intersecting the first direction, for example, a direction orthogonal to the first direction). In addition, the second terminal 132 is fixed and electrically connected via a conductive adhesive layer. The conductive adhesive layer includes a plurality of particles having conductivity at least on the surface (hereinafter referred to as conductive particles). The connection member 200 is electrically connected to the first terminal 112 via conductive particles in the conductive adhesive layer, and the connection member 202 is also electrically connected to the second terminal 132 via conductive particles in the conductive adhesive layer. Connected to.

  The light emitting device 10 includes a sealing member 220. The sealing member 220 includes a metal sheet 180 and a resin film 190.

  The metal sheet 180 is formed using a metal such as aluminum and has a sheet shape, for example, a metal foil or a metal film. By using the metal sheet, in addition to sealing the light emitting unit 140, the heat dissipation performance of the light emitting device 10 can be improved. The thickness of the metal sheet 180 is, for example, not less than 0.01 μm and not more than 0.5 mm, particularly preferably not less than 0.05 mm and not more than 2 mm. The edge of the metal sheet 180 has a shape that is pushed down compared to other portions of the metal sheet 180. Thus, a space is formed on the center side of the metal sheet 180. And the light emission part 140 and the desiccant 186 are arrange | positioned inside this space.

  A resin film 190 is provided on almost the entire surface of the metal sheet 180 facing the substrate 100. The resin film 190 is provided to fix the metal sheet 180 to the substrate 100 side, and is formed of, for example, an adhesive resin material or an adhesive. As a material constituting the resin film 190, for example, a material described as a sealing layer in Patent Document 1 can be used. Note that the first terminal 112, the second terminal 132, and the connecting members 200 and 202 are located outside the sealing member 220.

  As shown in FIG. 1, a recess 182 is formed on the edge of the metal sheet 180. The recess 182 is a portion of the metal sheet 180 that protrudes toward the resin film 190 and enters the resin film 190 in the thickness direction of the substrate 100. The depth of the recess 182 is, for example, not less than 0.1 μm and not more than 20 μm. In the example shown in FIG. 1, the concave portion 182 surrounds the light emitting unit 140, and the concave portion 182 has no break. In a direction orthogonal to the extending direction of the first terminal 112 (up and down direction in FIG. 3), the recess 182 overlaps at least a part of the first wiring portion 114. In addition, the recess 182 overlaps a part of the second terminal 132 in a direction orthogonal to the extending direction of the second terminal 132 (left-right direction in FIG. 3).

  A first insulating layer 155 is formed between the substrate 100 and the resin film 190. As shown in FIG. 3, the first insulating layer 155 is formed on a region of the first wiring portion 114 that overlaps with the recess 182. In the direction in which the first terminal 112 extends (left and right direction in FIG. 3), the first insulating layer 155 covers the entire first wiring portion 114. On the other hand, the first insulating layer 155 may cover only a part of the first wiring portion 114 in a direction (vertical direction in FIG. 3) orthogonal to the extending direction of the first terminal 112.

  The first insulating layer 155 is also formed in a region of the second terminal 132 that overlaps with the recess 182. In the direction in which the second terminal 132 extends (the vertical direction in FIG. 3), the first insulating layer 155 covers the entire second terminal 132. On the other hand, the first insulating layer 155 covers only a part of the first terminal 112 in the direction orthogonal to the extending direction of the second terminal 132 (the horizontal direction in FIG. 3).

  In the example shown in FIG. 3, the first insulating layer 155 is divided into two first wiring portions 114 and two second terminals 132. However, these four first insulating layers 155 may be connected to each other. In this case, the first insulating layer 155 surrounds the light emitting unit 140 without a break.

  The first insulating layer 155 is formed in the same process as the second insulating layer 150. For this reason, the first insulating layer 155 is formed using the same material as the second insulating layer 150, and the thickness of the first insulating layer 155 is not less than 80% of the thickness of the second insulating layer 150. % Or less. However, the first insulating layer 155 may be formed in a separate process from the second insulating layer 150. In this case, the first insulating layer 155 is formed using a material different from that of the second insulating layer 150, and the first insulating layer 155 may have a thickness different from that of the second insulating layer 150. is there.

  6 is a cross-sectional view taken along the line AA in FIG. In this figure, the connecting member 200 and the conductive resin layer are omitted for the sake of explanation. As shown in this figure, the recess 182 is a portion of the metal sheet 180 that protrudes toward the resin film 190 and the first insulating layer 155. The width w of the recess 182 is, for example, not less than 0.1 mm and not more than 2 mm. Further, a portion of the resin film 190 that overlaps with the concave portion 182 (hereinafter referred to as a first region 192) is thinner than other portions of the resin film 190. For example, the first region 192 is thinner than a portion of the resin film 190 located between the light emitting unit 140 and the first insulating layer 155 (hereinafter referred to as a second region 194). The first region 192 is thinner than the portion of the resin film 190 that overlaps the light emitting unit 140 (hereinafter referred to as the third region 196). The thickness of the first region 192 is, for example, not less than 0.25% and not more than 50% of the thickness of the third region 196. As described above, the concave portion 182 surrounds the light emitting portion 140, and the concave portion 182 has no break. For this reason, the first region 192 also surrounds the light emitting unit 140, and the first region 192 is also unbroken.

  Further, as will be described later, the recess 182 and the first region 192 are formed by pressing the pressing member 300. Therefore, the resin film 190 is located outside the end portion of the metal sheet 180 on at least a part of the end surface of the connection member 200. In other words, a part of the resin film 190 is pushed out of the metal sheet 180.

  As described above, the recess 182 overlaps the first insulating layer 155. For this reason, each of the portion overlapping the first wiring portion 114 and the portion overlapping the second terminal 132 in the first region 192 overlaps the first insulating layer 155.

  The organic layer 120 is also formed on the portion of the second insulating layer 150 that covers the conductive portion 116. The organic layers 120 of the adjacent light emitting units 140 are connected to each other. If it does in this way, the organic layer 120 which the some light emission part 140 has can be connected mutually, and can be made into one organic layer. In this case, when the organic layer 120 is formed, it is not necessary to separate the organic layer 120 into each of the plurality of light emitting units 140.

  Next, the manufacturing method of the light-emitting device 10 is demonstrated using FIG. First, the first electrode 110 is formed on the substrate 100. In this step, the same layer as the first electrode 110 among the first terminal 112, the first wiring portion 114, and the second terminal 132 is also formed. Next, the conductive portion 116 and the conductive portions 160 and 170 are formed in the same process. Next, the second insulating layer 150 and the first insulating layer 155 are formed in the same process. Next, the organic layer 120 and the second electrode 130 are formed in this order.

  Next, the sealing member 220 is prepared. At this stage, the desiccant 186 and the resin film 190 are fixed to the surface of the metal sheet 180 facing the substrate 100. Next, the sealing member 220 is fixed to the substrate 100 using the resin film 190. Since the resin film 190 is formed of a thermoplastic resin, a heat press process is performed in this step.

  In this heat pressing process, as shown in FIG. 7, the frame-shaped pressing member 300 is pressed against the edge of the metal sheet 180. As a result, a recess 182 is formed in the metal sheet 180, and the first region 192 of the resin film 190 becomes thin.

  Thereafter, the connection member 200 is connected to the first terminal 112, and the connection member 202 is connected to the second terminal 132.

  As described above, in the present embodiment, the light emitting unit 140 is sealed by the sealing member 220. The sealing member 220 has a configuration in which a metal sheet 180 and a resin film 190 are stacked. Since the resin film 190 is exposed at the end surface of the sealing member 220, there is a possibility that moisture may reach the light emitting unit 140 through the resin film 190. In addition, the same phenomenon occurs with oxygen, and the light emitting part 140 is seriously damaged, and this causes light emission abnormal parts such as dark spots. On the other hand, in the present embodiment, the resin film 190 is thin in the first region 192. Movement is limited by the reduced area and volume of the path for the invading moisture and oxygen. Therefore, the possibility that moisture or oxygen reaches the light emitting unit 140 through the resin film 190 is reduced. In addition, since the first region 192 of the resin film 190 overlaps the first insulating layer 155, the first wiring portion 114 (or the second terminal 132) is short-circuited with the metal sheet 180 at the portion overlapping the first region 192. Can be suppressed.

(Modification 1)
FIG. 8 is a cross-sectional view illustrating a configuration and a manufacturing method of the light emitting device 10 according to the first modification, and corresponds to FIG. 7 of the embodiment. The light emitting device 10 according to this modification has the same configuration as the light emitting device 10 according to the embodiment except for the following points.

  First, the pressing member 300 overlaps the edge of the metal sheet 180. For this reason, the recess 182 of the metal sheet 180 extends to the edge of the metal sheet 180.

  Also in this modification, the resin film 190 is thin in the first region 192, as in the embodiment. Therefore, the possibility that moisture or oxygen reaches the light emitting unit 140 through the resin film 190 is reduced. In addition, since the first region 192 overlaps with the first insulating layer 155, it is possible to suppress the first wiring part 114 and the second terminal 132 from being short-circuited with the metal sheet 180 at a portion overlapping the first region 192.

(Modification 2)
FIG. 9 is a cross-sectional view illustrating a configuration and a manufacturing method of the light-emitting device 10 according to Modification Example 2, and corresponds to FIG. 7 of the embodiment. The light emitting device 10 according to this modification has the same configuration as the light emitting device 10 according to the embodiment except for the following points.

  First, the pressing member 300 has at least one convex portion 302 on the surface pressed against the metal sheet 180. For this reason, a recess 184 is further formed on the bottom surface of the recess 182 of the metal sheet 180. As a result, the portion of the first region 192 that overlaps the recess 184 is thinner than the other portion of the first region 192.

  Also in this modification, the resin film 190 is thin in the first region 192, as in the embodiment. In addition, a part of the first region 192 is thinner than the other part. Therefore, the possibility that moisture or oxygen reaches the light emitting unit 140 via the resin film 190 is further reduced. In addition, since the first region 192 overlaps with the first insulating layer 155, it is possible to suppress the first wiring part 114 and the second terminal 132 from being short-circuited with the metal sheet 180 at a portion overlapping the first region 192.

  As mentioned above, although embodiment and the Example were described with reference to drawings, these are illustrations of this invention and can also employ | adopt various structures other than the above.

DESCRIPTION OF SYMBOLS 10 Light-emitting device 100 Board | substrate 110 1st electrode 114 1st wiring part 120 Organic layer 130 2nd electrode 132 2nd terminal 134 2nd wiring part 140 Light-emitting part 150 2nd insulating layer 155 1st insulating layer 180 Metal sheet 182 Recessed part 184 Recessed part 190 Resin film 192 First region 194 Second region 196 Third region 220 Sealing member 300 Pressing member 302 Convex portion

Claims (8)

A substrate,
A light emitting part formed on the substrate;
A wiring part formed on the substrate and electrically connected to the light emitting part;
A first insulating layer formed on at least a part of the wiring portion;
A resin film covering at least a part of the wiring part and the light emitting part;
A metal sheet located on the resin film and covering at least a part of the wiring part and the light emitting part;
With
At least a part of the end portion of the resin film is exposed,
In the light emitting device, a first region that is at least a part of a region of the resin film that overlaps the first insulating layer is thinner than a portion of the resin film that overlaps an end portion of the metal sheet .   The light-emitting device according to claim 1.
  The first region is a light emitting device thinner than a second region of the resin film located between the light emitting unit and the first insulating layer. The light-emitting device according to claim 1 or 2 ,
The first region is a light emitting device thinner than a third region of the resin film located on the light emitting unit. In the light-emitting device as described in any one of Claims 1-3 ,
A light emitting device comprising a second insulating layer that defines the light emitting portion and is made of the same material as the first insulating layer. The light-emitting device according to claim 4 .
The thickness of the said 1st insulating layer is a light-emitting device which is 80 to 105% of the thickness of the said 2nd insulating layer. In the light-emitting device as described in any one of Claims 1-5 ,
The light-emitting device in which at least a part of a region of the metal sheet that overlaps the first region protrudes toward the resin film. In the light-emitting device as described in any one of Claims 1-6 ,
A part of the first region is a light emitting device thinner than the other part of the first region. In the light-emitting device as described in any one of Claims 1-7 ,
The light emitting unit is a light emitting device having an organic layer.

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