A packaging structure

Abstract

The present application discloses a packaging structure, including: a packaging body having a mounting surface and a receiving groove covering the mounting surface; a light-emitting unit provided on the mounting surface; a diversion unit provided inside the packaging body for aggregating moisture invading the inside of the packaging body. Wherein, when moisture enters the receiving groove, the moisture adsorbs on the side wall of the corresponding diversion unit and aggregates to form water droplets. Due to the gravitational force of the water droplets, the water droplets flow along the side wall of the diversion unit to the adsorption layer, so that all the moisture in the receiving groove is absorbed by the adsorption layer, improving the reliability of the present packaging structure and effectively avoiding the failure of the light-emitting unit.

Description

Technical Field

[0001] The present disclosure generally relates to the field of packaging technology, and particularly to a packaging structure. Background Art

[0002] OLED is an optoelectronic device that emits light through carrier injection and recombination. The specific process is that electrons are injected through the metal cathode, transmitted through the electron transport material to the light-emitting layer, holes are injected through the metal anode, transmitted through the hole transport material to the light-emitting layer, electrons and holes recombine in the light-emitting layer to form excitons, and the excitons de-excite to emit light. OLED has attracted much attention due to its good light emission uniformity, thinness, bendability, flexibility, stretchability, etc.

[0003] OLED is extremely sensitive to water and oxygen. Therefore, it is necessary to package OLED. Glass packaging is a commonly used packaging method at present. However, the UV glue used in glass packaging does not have water-blocking performance. To solve this problem, a desiccant is usually coated in the packaging area. Therefore, we propose a packaging structure to solve the above problems. Summary of the Invention

[0004] In view of the above defects or deficiencies in the prior art, it is desirable to provide a packaging structure that improves packaging reliability.

[0005] The present application provides a packaging structure, including:

[0006] A packaging body having an installation surface and a receiving groove covering the installation surface; a light-emitting unit is provided on the installation surface;

[0007] A diversion unit disposed inside the packaging body for gathering water vapor invading the inside of the packaging body.

[0008] According to the technical solution provided by the embodiment of the present application, it further includes an adsorption layer disposed on the bottom wall of the receiving groove and / or the installation surface; the diversion unit is in contact connection with the adsorption layer.

[0009] According to the technical solution provided by the embodiment of the present application, the bottom of the diversion unit is connected to the adsorption layer, or penetrates the adsorption layer and is connected to the bottom wall of the receiving groove or the installation surface.

[0010] According to the technical solution provided by the embodiment of the present application, the diversion unit includes: at least one set of diversion components;

[0011] The diversion component has a plurality of diversion members distributed in an array; the extending direction of each diversion member is perpendicular to the installation surface.

[0012] According to the technical solution provided by the embodiment of the present application, the diversion unit includes: at least one group of first diversion components and at least one group of second diversion components; the first diversion components are arranged closer to the center of the light-emitting unit than the second diversion components;

[0013] Both the first diversion components and the second diversion components have a plurality of diversion members distributed in an array; the diversion members of the first diversion components form an angle with the bottom wall of the accommodation groove, and the opening of the angle faces the light-emitting unit; the extending direction of the diversion members of the second diversion components is perpendicular to the installation surface.

[0014] According to the technical solution provided by the embodiment of the present application, the diversion member is a cone structure, and the end surface of the diversion member at the bottom end of the cone can be connected to the adsorption layer, the bottom wall of the accommodation groove or the installation surface.

[0015] According to the technical solution provided by the embodiment of the present application, the edge of the opening of the accommodation groove is connected to the installation surface through a sealing frame adhesive;

[0016] The height of the diversion member is greater than or equal to the depth of the accommodation groove and less than the sum of the depth of the accommodation groove and the thickness of the sealing frame adhesive.

[0017] According to the technical solution provided by the embodiment of the present application, the diversion member is a cone structure formed by stacking multiple layers of water vapor diversion layers, and the hydrophilicity of the multiple layers of water vapor diversion layers increases layer by layer from the bottom end of the cone to the tip of the cone, and / or, pores are formed in the diversion member, and the diameter of the pores gradually decreases from the bottom end of the cone to the tip of the cone.

[0018] According to the technical solution provided by the embodiment of the present application, the material of the diversion member is fluorinated ethylene propylene; the sealing frame adhesive is uv glue; the adsorption layer is a desiccant layer.

[0019] In summary, the present application specifically discloses the specific structure of a packaging structure. The present application uses the upper surface of the substrate as the installation surface, sets a light-emitting unit on the installation surface, opens an accommodation groove on one side of the packaging cover plate, covers it on the installation surface, and sets a diversion unit inside the space formed by the accommodation groove and the installation surface to gather the water vapor invading the inside of the packaging body and prevent the water vapor invading the inside of the packaging structure from damaging the light-emitting unit. Due to the disordered movement of the water vapor, the adsorption layer cannot absorb all the water vapor in the space formed by the accommodation groove and the installation surface. Therefore, a diversion unit is set, which has a guiding and gathering effect on the water vapor invading the packaging body. After the water vapor is gathered, it is guided to the adsorption layer under the action of gravity. When water vapor enters the accommodation groove, the water vapor adsorbs on the side wall of the corresponding diversion unit and gathers to form water droplets. Due to the gravity of the water droplets, they flow along the side wall of the diversion unit to the adsorption layer, so that all the water vapor in the accommodation groove is absorbed by the adsorption layer, improving the reliability of the packaging structure and effectively avoiding the failure of the light-emitting unit. Description of the Drawings

[0020] Other features, objects, and advantages of the present application will become more apparent by reading the following detailed description of non - restrictive embodiments with reference to the accompanying drawings:

[0021] Figure 1 It is a schematic structural diagram of Embodiment 1.

[0022] Figure 2 It is a schematic structural diagram of Embodiment 2.

[0023] Figure 3 It is a schematic structural diagram of Embodiment 3.

[0024] Figure 4 It is a schematic structural diagram of Embodiment 4.

[0025] Figure 5 It is a schematic structural diagram of Embodiment 5.

[0026] Figure 6 It is a schematic structural diagram of a multi - layer water vapor diversion layer.

[0027] Reference numerals in the figure: 1, light - emitting unit; 2, receiving groove; 3, adsorption layer; 4, diversion member; 5, substrate; 6, encapsulation cover plate; 7, sealing frame adhesive; 8, pore. Detailed Embodiments

[0028] The present application will be further described in detail below with reference to the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the related invention and are not intended to limit the invention. Additionally, it should be noted that for ease of description, only parts related to the invention are shown in the drawings.

[0029] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The present application will be described in detail below with reference to the drawings and embodiments.

[0030] Embodiment 1

[0031] Please refer to Figure 1 the schematic structural diagram of the first embodiment of a packaging structure provided by the present application shown in

[0032] a packaging body, the packaging body having an installation surface and a receiving groove 2 covering the installation surface; the light - emitting unit 1 is provided on the installation surface;

[0033] a diversion unit, the diversion unit being disposed inside the packaging body for aggregating water vapor invading the inside of the packaging body.

[0034] In this embodiment, the packaging body includes:

[0035] A substrate 5, whose upper surface serves as a mounting surface for mounting a light-emitting unit 1; wherein, the type of the light-emitting unit 1 is, for example, an organic electroluminescent device or a quantum dot light-emitting device;

[0036] A packaging cover plate 6, which is a cover structure that cooperates with the substrate 5 to package the light-emitting unit 1. A receiving groove 2 is formed on one side of the packaging cover plate 6. When the edges of the packaging cover plate 6 and the substrate 5 are connected by a sealing adhesive 7, the receiving groove 2 covers the light-emitting unit 1; wherein, the type of the sealing adhesive 7 is, for example, a uv adhesive.

[0037] An adsorption layer 3, which is arranged on the bottom wall of the receiving groove 2 and is used for adsorbing water vapor in the space formed by the receiving groove 2 and the mounting surface; here, the type of the adsorption layer 3 is, for example, a desiccant layer.

[0038] A diversion unit, which is connected to the adsorption layer 3 or penetrates through the adsorption layer 3 and is connected to the bottom wall of the receiving groove. Among them, the diversion unit includes: at least one set of diversion components. The diversion components have a plurality of diversion members 4 distributed in an array. The diversion members 4 can surround the light-emitting unit 1 or be located on one side or both sides of the light-emitting unit 1 to guide the water vapor entering the receiving groove 2; and, the extending direction of each diversion member 4 is perpendicular to the mounting surface, as Figure 1 shown, the extending direction of the diversion member 4 is the vertical direction.

[0039] Among them, the diversion member 4 is a cone structure. The end face of the diversion member 4 at the bottom of the cone can be connected to the adsorption layer 3 or penetrate through the adsorption layer 3 and be connected to the bottom wall of the receiving groove 2. And the height of the diversion member 4 is greater than or equal to the depth of the receiving groove 2 and less than the sum of the depth of the receiving groove 2 and the thickness of the sealing adhesive 7, so that the diversion member 4 forms a guiding barrier to effectively block the probability of water vapor contacting the light-emitting unit 1.

[0040] Specifically, the diversion members 4 form a micro-needle structure around the light-emitting unit 1. Among them, the principle of action of the micro-needle structure is similar to that of cactus spines. In arid regions, the survival of cacti mainly depends on their spines. The spines of cacti can collect water vapor condensates in the air, so that the water vapor condensates can adhere to the surface of their needles. In addition, the principle of the beetles in the Namib Desert obtaining water from the thin air through their own elytra on their backs is the same. The height of the diversion member 4 is 1 - 1500 μm, preferably 1 - 50 μm; the diameter is 0.1 - 1000 μm, preferably 0.1 - 100 μm.

[0041] Among them, the material of the diversion member 4 is, for example, fluorinated ethylene propylene, and the diversion member 4 can be prepared by laser engraving.

[0042] Specifically, first place the whole piece of fluorinated ethylene propylene on the bottom wall or mounting surface of the receiving groove 2 where the adsorption layer has been prepared, and then use a laser engraving machine to engrave from its top surface downward. Control the cutting depth by controlling the power of the laser engraving machine.

[0043] As Figure 1 shown, there is a set of diversion components, which includes 10 diversion members 4. For example, according to the contour shape of the light-emitting unit 1, obtain the array distribution path of the diversion members 4, so that the diversion members 4 are evenly distributed around the light-emitting unit 1, and each diversion member 4 penetrates through the adsorption layer 3 and is connected to the bottom wall of the receiving groove 2. The principle of absorbing water vapor is as follows: The water vapor entering the receiving groove 2 is adsorbed on the conical surface of the diversion member 4 and aggregates into water droplets. Due to the gravity of the water droplets, they flow along the conical surface of the diversion member 4 to the adsorption layer 3, so that the water vapor in the receiving groove 2 can be quickly absorbed by the adsorption layer 3, improving the reliability of this packaging structure and effectively avoiding the failure of the light-emitting unit 1. Here, since the flow direction of the water vapor is affected by its gravity, therefore, to ensure that the water vapor is effectively absorbed, when this structure is in use, the light-emitting unit 1 emits light toward the bottom wall of the receiving groove 2.

[0044] Embodiment 2

[0045] Based on Embodiment 1, in this embodiment, the adsorption layer 3 is installed on the mounting surface of the substrate 5, and the adsorption layer 3 is arranged around the light-emitting unit 1.

[0046] In this embodiment, the tip of the diversion member 4 of the diversion unit installed on the adsorption layer 3 faces the inside of the receiving groove 2, and it can also guide the water vapor to be quickly absorbed by the adsorption layer 3. As Figure 2 shown, taking a set of diversion components as an example, the diversion member 4 penetrates through the adsorption layer 3 and is connected to the mounting surface. Since the flow direction of the water vapor is affected by its gravity, when this structure is in use, the light-emitting unit 1 emits light toward the mounting surface.

[0047] Embodiment 3

[0048] In this embodiment, Embodiment 1 and Embodiment 2 are combined, and the adsorption layer 3 is arranged on the bottom wall of the receiving groove 2 and the mounting surface of the substrate 5.

[0049] In this embodiment, the diversion units on one side of the receiving groove 2 and the diversion units on one side of the substrate 5 can be arranged in sequence or alternately.

[0050] For example: when each diversion component of each diversion unit is a set, when arranged in sequence, the first arrangement method is: As Figure 3As shown, the flow guiding assembly on one side of the receiving groove 2 is disposed closer to the light emitting unit 1 than the flow guiding assembly on one side of the substrate 5; the second arrangement is that the flow guiding assembly on one side of the receiving groove 2 is disposed away from the light emitting unit 1 relative to the flow guiding assembly on one side of the substrate 5, and in the first arrangement and the second arrangement, the flow guiding members 4 of the two sets of flow guiding assemblies can be arranged in a staggered manner or the flow guiding members 4 of the two sets of flow guiding assemblies can be arranged in one-to-one correspondence; when arranged alternately, the connecting line shape of the orthographic projections of the flow guiding member 4 of one set of flow guiding assemblies and the flow guiding member 4 of the other set of flow guiding assemblies on the mounting surface is similar to the contour shape of the light emitting unit 1.

[0051] Since the adsorption layer 3 and the flow guiding unit are distributed on both the receiving groove 2 and the mounting surface, regardless of how this structure is used, the light emitting direction of the light emitting unit 1 is not restricted, and moreover, the two air guiding devices can form a more airtight guiding barrier, separating the water vapor from the light emitting unit 1 to the greatest extent. For example Figure 3 In the placement manner of the present structure shown, the receiving groove 2 is in the upper part in the figure, each flow guiding member 4 penetrates through the adsorption layer 3 and is connected to the bottom wall of the corresponding receiving groove 2 or the mounting surface. Assuming that the light emitting direction of the light emitting unit 1 faces the mounting surface, the adsorption layer 3 on the receiving groove 2 absorbs water vapor at a normal speed, and the water vapor that comes into contact with the flow guiding member 4 on one side of the receiving groove 2, after aggregating into water droplets, will quickly drip onto the adsorption layer 3 on the mounting surface under its gravity. Moreover, the water vapor aggregated by the flow guiding member 4 on the mounting surface will, according to its gravity, flow along the conical surface of the flow guiding member 4 onto the adsorption layer 3 on the mounting surface, enabling the adsorption layer 3 to quickly absorb water vapor to improve the reliability of this encapsulation structure.

[0052] Embodiment 4

[0053] Based on Embodiment 1, in this embodiment, the flow guiding unit is designed as: at least one set of first flow guiding assemblies and at least one set of second flow guiding assemblies; and the first flow guiding assemblies are disposed closer to the center of the light emitting unit 1 than the second flow guiding assemblies; both the first flow guiding assemblies and the second flow guiding assemblies include a plurality of flow guiding members 4 arranged in an array.

[0054] In this embodiment, as Figure 4 shown, the flow guiding unit is installed on the bottom wall of the receiving groove 2, the flow guiding member 4 of the first flow guiding assembly forms an angle A with the bottom wall of the receiving groove 2, the opening of the angle A faces the light emitting unit 1, and the angle A is an acute angle; the extending direction of the flow guiding member 4 of the second flow guiding assembly is perpendicular to the mounting surface, and the extending direction of the flow guiding member 4 of the second flow guiding assembly is Figure 4 the vertical direction in

[0055] Among them, the arrangement manner of the flow guiding member 4 of the first flow guiding assembly and the flow guiding member 4 of the second flow guiding assembly can be a staggered distribution or a one-to-one correspondence arrangement;

[0056] As Figure 4As shown, the first flow guiding component and the second flow guiding component are both a group, forming a double-layer guiding barrier. The flow guiding members 4 of both the first flow guiding component and the second flow guiding component penetrate through the adsorption layer 3 and are connected to the bottom wall of the corresponding accommodation groove 2 or the mounting surface. The principle of water vapor absorption is as follows: The water vapor entering the accommodation groove 2 will first be adsorbed on the second flow guiding component. However, due to the gaps between two adjacent flow guiding members 4 of the second flow guiding component, a small amount of water vapor will enter through these gaps. The tip of the first flow guiding component is adjacent to the light emitting unit 1 and can adsorb a small amount of water vapor around the light emitting unit 1. Moreover, since the flow guiding member 4 of the first flow guiding component has an inclination angle, the water vapor adhering to its conical surface can quickly flow towards the adsorption layer 3. Through the cooperation of the first flow guiding component and the second flow guiding component, the water vapor in the accommodation groove 2 can be effectively adsorbed, preventing the light emitting unit 1 from failing. When this structure is in use, the light emitting unit 1 emits light towards the bottom wall of the accommodation groove 2.

[0057] Embodiment 5

[0058] This embodiment combines Embodiment 2 and Embodiment 4. An adsorption layer 3 is provided on the mounting surface of the substrate 5, and the tip of the flow guiding member 4 of the flow guiding unit on one side of the mounting surface faces into the accommodation groove 2. The flow guiding unit on the bottom wall side of the accommodation groove 2 includes at least one group of first flow guiding components and at least one group of second flow guiding components.

[0059] In this embodiment, the flow guiding unit on one side of the substrate 5 is arranged relatively far from the center of the light emitting unit 1 compared to the flow guiding unit on the bottom wall side of the accommodation groove 2. The arrangement of the flow guiding members 4 of the flow guiding unit on one side of the substrate 5 and the second flow guiding components of the flow guiding unit on the bottom wall side of the accommodation groove 2 can be staggeredly distributed, can be arranged in one-to-one correspondence, or the shape of the connection line of their orthographic projections on the mounting surface can be similar to the contour shape of the light emitting unit 1.

[0060] Since both the accommodation groove 2 and the mounting surface are provided with the adsorption layer 3 and the flow guiding unit, regardless of how this structure is used, the light emitting direction of the light emitting unit 1 is not restricted. Moreover, the two air guiding devices can form a more airtight guiding barrier, separating the water vapor from the light emitting unit 1 to the greatest extent. As Figure 5 shown, each flow guiding component of each flow guiding unit is a group, and each flow guiding member 4 penetrates through the adsorption layer 3 and is connected to the bottom wall of the corresponding accommodation groove 2 or the mounting surface. For the upper part of the accommodation groove 2 in the figure, assuming that the light emitting direction of the light emitting unit 1 is towards the bottom wall of the accommodation groove 2, the adsorption layer 3 on the mounting surface absorbs water vapor at a normal speed, and the water vapor contacting the flow guiding member 4 on the mounting surface side will quickly drip onto the adsorption layer 3 on the accommodation groove 2 under its gravity.

[0061] Moreover, the water vapor in contact with the second diversion assembly on the bottom wall of the accommodation groove 2 will flow along the conical surface of the diversion member 4 of the second diversion assembly towards the adsorption layer 3 on the bottom wall of the accommodation groove 2 under the action of its gravity. The tip of the first diversion assembly is adjacent to the light-emitting unit 1, adsorbing a small amount of water vapor around the light-emitting unit, enabling the water vapor adhering to its conical surface to quickly flow towards the adsorption layer 3 on the bottom wall of the accommodation groove 2, effectively adsorbing the water vapor in the accommodation groove 2 and preventing the light-emitting unit 1 from failing.

[0062] Embodiment 6

[0063] Based on Embodiment 1, in this embodiment, the diversion member 4 is designed as a conical structure formed by stacking multiple layers of water vapor diversion layers;

[0064] The hydrophilicity of the multiple layers of water vapor diversion layers increases layer by layer from the bottom of the cone to the tip of the cone.

[0065] In this embodiment, the multiple layers of water vapor diversion layers are in a conical structure, and the surface energy of the multiple layers of water vapor diversion layers gradually increases from the bottom of the cone to the tip of the cone, and the hydrophilicity of the multiple layers of water vapor diversion layers increases layer by layer from the bottom of the cone to the tip of the cone.

[0066] Among them, the number of layers of the water vapor diversion layer is at least 3 layers, and the material of each layer is, for example, at least 3 materials such as bionic gold, urethane compounds, aldehyde compounds, olefin compounds, aromatic hydrocarbon compounds, polyester compounds, epoxy compounds, silicon oxide, silicon oxynitride, titanium oxide, etc. Moreover, the design of each layer of the multiple layers of water vapor diversion layers conforms to the fact that the pore 8 gradually becomes smaller from the bottom end of the cone to the tip of the cone, the surface energy becomes larger from the bottom end of the cone to the tip of the cone, and the material becomes more hydrophilic from the bottom end of the cone to the tip of the cone. Each layer of the water vapor diversion layer can be prepared into a water vapor diversion structure by means of spin coating, slot coating, inkjet printing, PECVD, sputtering, etc.

[0067] Embodiment 7

[0068] Based on Embodiment 1, in this embodiment, as Figure 6 shown, the diversion member 4 is provided with pores 8, and the diameter of the pores 8 gradually decreases from the bottom of the cone to the tip of the cone. The principle of its action is that as the pores 8 decrease, the capillary force will increase, enabling the water vapor to quickly flow towards the side with smaller pores; the water vapor entering the accommodation groove 2 is captured by the tip part of the cone of the diversion member 4, the water vapor enters the pores 8, and is guided by the pores 8 to flow towards the adsorption layer 3 and is absorbed by the adsorption layer 3, reducing or blocking the contact between the water vapor and the light-emitting unit and improving the reliability of the packaging structure. Further, the diversion member 4 of this example can also be a conical structure formed by stacking multiple layers of water vapor diversion layers;

[0069] The hydrophilicity of the multiple layers of water vapor diversion layers increases layer by layer from the bottom of the cone to the tip of the cone.

[0070] The multi-layer water vapor diversion layer is in a conical structure, and the surface energy of the multi-layer water vapor diversion layer gradually increases from the cone bottom to the cone tip, and the hydrophilicity of the multi-layer water vapor diversion layer increases layer by layer from the cone bottom to the cone tip.

[0071] The above description is only a preferred embodiment of the present application and an explanation of the applied technical principles. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solution formed by the specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. For example, the technical solutions formed by mutually replacing the above features with the technical features (but not limited to) having similar functions disclosed in the present application.

Claims

1. An encapsulation structure, characterized in that, it includes: An encapsulation body, the encapsulation body has a mounting surface, and a receiving groove (2) covering the mounting surface; a light-emitting unit (1) is provided on the mounting surface; A diversion unit, the diversion unit is arranged inside the encapsulation body and is used to gather the water vapor invading the inside of the encapsulation body; The diversion unit includes: at least one group of diversion components; the diversion components have a plurality of diversion members (4) distributed in an array; the diversion member (4) is a cone structure, and the end surface of the diversion member (4) at the bottom end of the cone can be connected to the bottom wall of the receiving groove (2) or the mounting surface; It further includes an adsorption layer (3), and the adsorption layer (3) is arranged on the bottom wall of the receiving groove (2) and / or the mounting surface; The diversion unit is in contact connection with the adsorption layer (3); The bottom of the diversion unit is connected to the adsorption layer (3), or penetrates the adsorption layer (3) and is connected to the bottom wall of the receiving groove (2) or the mounting surface.

2. An encapsulation structure according to claim 1, characterized in that, The extending direction of each diversion member (4) is perpendicular to the mounting surface.

3. An encapsulation structure according to claim 2, characterized in that, The diversion units on one side of the receiving groove (2) and the diversion units on one side of the mounting surface are arranged in sequence or alternately.

4. An encapsulation structure according to claim 1, characterized in that, The diversion unit includes: at least one group of first diversion components and at least one group of second diversion components; the first diversion components are arranged relatively closer to the center of the light-emitting unit (1) than the second diversion components; Both the first diversion components and the second diversion components have a plurality of diversion members (4) distributed in an array; the diversion members (4) of the first diversion components form an angle with the bottom wall of the receiving groove (2), and the opening of the angle faces the light-emitting unit (1); the extending direction of the diversion members (4) of the second diversion components is perpendicular to the mounting surface.

5. An encapsulation structure according to claim 1, characterized in that, The edge of the opening of the receiving groove (2) is connected to the mounting surface through a sealing frame adhesive (7); The height of the diversion member (4) is greater than or equal to the depth of the receiving groove (2) and less than the sum of the depth of the receiving groove (2) and the thickness of the sealing frame adhesive (7).

6. An encapsulation structure according to claim 5, characterized in that, The diversion member (4) is a cone structure formed by stacking multiple layers of water vapor diversion layers, and the hydrophilicity of the multiple layers of water vapor diversion layers increases layer by layer from the bottom surface of the cone to the tip of the cone, and / or, pores (8) are provided in the diversion member (4), and the diameter of the pores (8) gradually decreases from the bottom surface of the cone to the tip of the cone.

7. An encapsulation structure according to claim 5, characterized in that, The material of the diversion member (4) is fluorinated ethylene propylene; the sealing frame adhesive (7) is a uv adhesive; the adsorption layer (3) is a desiccant layer.

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