Foaming material and refrigeration device
By using specific proportions of polyether polyol and other components in the insulation layer of the refrigerator to mix foaming, the problem of high thermal conductivity of existing foamed materials resulting in poor insulation effect of refrigerators is solved, and better insulation effect and reduced energy consumption and production costs are achieved.
Patent Information
- Application Number
- CN202510058682.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-14
- Publication Date
- 2025-04-25
AI Technical Summary
The existing foaming materials have a high thermal conductivity, which leads to poor insulation effect of the refrigerator, thereby increasing energy consumption.
The foaming material with a lower thermal conductivity is prepared by mixing and foaming the polyether polyol, surfactant, catalyst, water, foaming agent and isocyanate in a specific proportion.
The insulation effect of the refrigerator is improved, the energy consumption of the refrigerator is reduced, and the quality of foamed materials is reduced by reducing the molding density, thereby reducing production costs.
Smart Images
Figure BDA0005242467810000041 
Figure BDA0005242467810000081
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of foaming materials, and in particular to a foaming material and a refrigeration device. Background Art
[0002] With the improvement of people's living standards, refrigerators have become one of the indispensable electrical appliances in modern family life. The refrigerator body and door are usually equipped with an insulation layer, which can isolate the temperature exchange between the inside and outside of the refrigerator and prevent the external temperature from affecting the internal temperature of the refrigerator, thereby maintaining the internal temperature of the refrigerator constant, reducing the working times of the compressor, and achieving the purpose of energy saving.
[0003] The material of the heat-insulating layer is usually a foam material. However, the thermal conductivity of the existing foam material is relatively high, which results in a poor heat-insulating effect of the refrigerator. Summary of the invention
[0004] Based on this, an embodiment of the present application provides a foaming material and a refrigeration device.
[0005] In a first aspect, an embodiment of the present application provides a foaming material, which includes, by weight: 85-93 parts of polyether polyol, 3-5 parts of surfactant, 1-5 parts of catalyst, 2.5-5 parts of water, 15-19 parts of foaming agent and 140-150 parts of isocyanate.
[0006] In some embodiments, the polyether polyol is formed by copolymerizing propylene oxide and 4-butylbenzene-1,2-diamine using 4-butylbenzene-1,2-diamine as an initiator; and / or,
[0007] The hydroxyl value of the polyether polyol is 540 mg KOH / g to 560 mg KOH / g, the viscosity of the polyether polyol is 5100 mPa.s to 5300 mPa.s, the pH value of the polyether polyol is 5 to 7, and the relative density of the polyether polyol is 1.1 to 1.2.
[0008] In some embodiments, the surfactant comprises silicone oil; and / or,
[0009] The isocyanate includes polymethylene polyphenyl isocyanate.
[0010] In some embodiments, the surfactant includes at least one of silicone oil AK88310 and silicone oil B8496 and at least one of silicone oil UR5981 and silicone oil UR-5961; and / or,
[0011] The viscosity of the polymethylene polyphenyl isocyanate is 180 mPa·s to 220 mPa·s, and the isocyanate content of the polymethylene polyphenyl isocyanate is 30 wt % to 32.2 wt %.
[0012] In some embodiments, the blowing agent comprises at least one of cyclopentane and n-butane; and / or,
[0013] The catalyst includes at least one of a foaming catalyst, a gelling catalyst and a trimerization catalyst.
[0014] In some embodiments, when the blowing agent consists of cyclopentane and n-butane, the mass ratio of the cyclopentane to the n-butane is (7-8):1; and / or,
[0015] When the catalyst consists of a foaming catalyst, a gel catalyst and a trimerization catalyst, the mass ratio of the foaming catalyst, the gel catalyst and the trimerization catalyst is (0.8-1.2):(0.8-1.2):(0.8-1.2).
[0016] In some embodiments, the foaming catalyst includes pentamethyldiethylenetriamine, the gelling catalyst includes at least one of BX6212 and BX6211B, and the trimerization catalyst includes 2-hydroxy-N,N,N-trimethyl-1-propylamine formate.
[0017] In a second aspect, an embodiment of the present application provides a refrigeration device, comprising a thermal insulation layer, wherein the thermal insulation layer comprises the foaming material as described above.
[0018] In some embodiments, the refrigeration device includes a box body, the box body includes a shell and a box liner that are spaced apart, the box liner is arranged on the inner side of the shell, and the insulation layer is provided between the shell and the box liner.
[0019] In some embodiments, the refrigeration device includes a door body, and the door body includes a door panel and a door liner that are spaced apart, and the insulation layer is provided between the door panel and the door liner.
[0020] The foaming material provided in the embodiment of the present application can be used to prepare the insulation layer of the refrigerator. The foaming material is prepared by mixing and foaming polyether polyol, surfactant, catalyst, water, foaming agent and isocyanate in a specific proportion. The obtained foaming material has a low thermal conductivity, which can improve the insulation effect of the refrigerator and thus reduce the energy consumption of the refrigerator. In addition, the foaming material also has a small molding density. When the volume of the insulation layer is constant, the mass of the foaming material filled in the refrigerator can be reduced by reducing the molding density, thereby reducing the production cost of the refrigerator. DETAILED DESCRIPTION
[0021] The technical solutions in the embodiments of the present application are described clearly and completely below. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.
[0022] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0023] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.
[0024] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.
[0025] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.
[0026] The embodiment of the present application provides a foaming material, which includes, by weight: 85-93 parts of polyether polyol, 3-5 parts of surfactant, 1-5 parts of catalyst, 2.5-5 parts of water, 15-19 parts of foaming agent and 140-150 parts of isocyanate.
[0027] Illustratively, in parts by weight, in the foaming material, the number of polyether polyols may be 85 parts, 87 parts, 89 parts, 91 parts, 93 parts, etc., the number of surfactants may be 3 parts, 5 parts, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, etc., the number of catalysts may be 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, etc., the number of water may be 2.5 parts, 5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts, 5 parts, etc., the number of blowing agents may be 15 parts, 16 parts, 17 parts, 18 parts, 19 parts, etc., and the number of isocyanates may be 140 parts, 142 parts, 145 parts, 148 parts, 150 parts, etc.
[0028] Before use, the foaming material of the embodiment of the present application first needs to mix the components under a pressure of 3-5 bar, and then use a gun head to inject the mixture into a mold (such as a refrigerator body or a refrigerator door). The polyether polyol and isocyanate react to form polyurethane foam. During the reaction, the foaming agent evaporates to form pores. Since the polyurethane foam is a hard foam, it will form a closed cell rate of more than 95%. The pores will lock the foaming agent to prevent the foaming agent from evaporating and escaping.
[0029] The foaming material provided in the embodiment of the present application can be used to prepare the insulation layer of the refrigerator. The foaming material is prepared by mixing and foaming polyether polyol, surfactant, catalyst, water, foaming agent and isocyanate in a specific proportion. The obtained foaming material has a low thermal conductivity, which can improve the insulation effect of the refrigerator and thus reduce the energy consumption of the refrigerator. In addition, the foaming material also has a small molding density. When the volume of the insulation layer is constant, the mass of the foaming material filled in the refrigerator can be reduced by reducing the molding density, thereby reducing the production cost of the refrigerator.
[0030] Illustratively, the polyether polyol is formed by copolymerizing propylene oxide and 4-butylbenzene-1,2-diamine using 4-butylbenzene-1,2-diamine as an initiator.
[0031] The CAS number of the 4-butylbenzene-1,2-diamine is 3663-23-8, and the structural formula of the 4-butylbenzene-1,2-diamine is:
[0032]
[0033] It should be noted that, since 4-butylbenzene-1,2-diamine has a toluenediamine structure, the polyether polyol prepared with 4-butylbenzene-1,2-diamine as an initiator has a self-catalytic function, and has a high reaction activity with polymethylene polyphenyl isocyanate, which can reduce the use of catalysts. At the same time, the curing speed in the later stage of foaming is faster, and the thermal conductivity of the generated polyurethane rigid foam material is lower, thereby achieving a better thermal insulation effect.
[0034] Exemplarily, the hydroxyl value of the polyether polyol is 540 mg KOH / g to 560 mg KOH / g, the viscosity (25°C) of the polyether polyol is 5100 mPa.s to 5300 mPa.s, the pH value of the polyether polyol is 5 to 7, the relative density of the polyether polyol is 1.1 to 1.2, and in some embodiments, the relative density of the polyether polyol is 1.114.
[0035] Exemplarily, the surfactant includes silicone oil. In some embodiments, the surfactant includes at least one of silicone oil AK88310 and silicone oil B8496 and at least one of silicone oil UR5981 and silicone oil UR-5961.
[0036] In some embodiments, silicone oil AK88310 and silicone oil B8496 are purchased from Dongguan Yingxin New Materials Technology Co., Ltd., and silicone oil UR5981 and silicone oil UR-5961 are purchased from Aoshijia Material Technology (Shanghai) Co., Ltd.
[0037] Exemplarily, the blowing agent includes at least one of cyclopentane and n-butane.
[0038] Exemplarily, when the blowing agent consists of cyclopentane (CP) and n-butane (R600), the mass ratio of cyclopentane to n-butane may be (7-8):1, such as 7:1, 7.2:1, 7.5:1, 7.8:1, 8:1, and the like.
[0039] It can be understood that cyclopentane is a high-boiling point alkane foaming agent, and n-butane is a low-boiling point alkane foaming agent (boiling point is -0.5°C). When the foaming agent is composed of cyclopentane and n-butane, among the foaming agents, cyclopentane plays a major foaming role, and n-butane plays an auxiliary foaming role. However, due to the high boiling point of cyclopentane, it is easy to cause the density of the foam to be too high. Therefore, by adding the low-boiling point foaming agent n-butane, the molding density of the foamed material can be reduced.
[0040] Exemplarily, the catalyst includes at least one of a foaming catalyst, a gelling catalyst and a trimerization catalyst.
[0041] Exemplarily, when the catalyst consists of a foaming catalyst, a gel catalyst and a trimerization catalyst, the mass ratio of the foaming catalyst, the gel catalyst and the trimerization catalyst can be (0.8-1.2):(0.8-1.2):(0.8-1.2), for example, 1:1:1, 0.8:1:0.8, 0.8:1:1.2, 1.2:1:0.8, 1.2:1:1.2, etc.
[0042] Exemplarily, the foaming catalyst includes pentamethyldiethylenetriamine (PC-5), the gelling catalyst includes at least one of BX6212 and BX6211B, and the trimerization catalyst includes 2-hydroxy-N,N,N-trimethyl-1-propylamine formate (TMR-2).
[0043] In some embodiments, pentamethyldiethylenetriamine (PC-5) was purchased from Dongguan Yingxin New Materials Technology Co., Ltd.
[0044] In some embodiments, gel catalysts BX6212 and BX6211B are purchased from Jiahua Chemical New Materials Co., Ltd.
[0045] In some embodiments, 2-hydroxy-N,N,N-trimethyl-1-propylamine formate (TMR-2) was purchased from Xindian Chemical Materials (Shanghai) Co., Ltd.
[0046] Exemplarily, the isocyanate includes polymethylene polyphenyl isocyanate.
[0047] Exemplarily, the viscosity of the polymethylene polyphenyl isocyanate is 180 mPa·s to 220 mPa·s, for example, 180 mPa·s, 190 mPa·s, 200 mPa·s, 210 mPa·s, 220 mPa·s, etc.
[0048] Illustratively, the isocyanate (HNCO) content of the polymethylene polyphenyl isocyanate is 30 wt% to 32.2 wt%, for example, 30 wt%, 30.5 wt%, 31.1 wt%, 31.6 wt%, 32.2 wt%, and the like.
[0049] Illustratively, the polymethylene polyphenyl isocyanate is purchased from Wanhua Chemical Group Co., Ltd.
[0050] Exemplarily, the water is deionized water.
[0051] An embodiment of the present application further provides a refrigeration device, comprising a thermal insulation layer, wherein the thermal insulation layer comprises the foaming material in any of the above embodiments.
[0052] Exemplarily, the refrigeration device includes a box body, the box body includes a shell and a box liner that are spaced apart, the box liner is arranged on the inner side of the shell, and the insulation layer is provided between the shell and the box liner.
[0053] Exemplarily, the refrigeration device includes a door body, the door body includes a door panel and a door liner that are spaced apart, and the thermal insulation layer is provided between the door panel and the door liner.
[0054] Exemplarily, the refrigeration device can be a refrigerator, a freezer, a cold drink machine, a refrigerated wine cabinet, a freezer, an ice chest, an ice cream machine, an ice maker, etc.
[0055] The foaming material of the present application is described in detail below in the form of specific embodiments.
[0056] Example 1
[0057] A foaming material, comprising, by weight, 89 parts of polyether polyol, 4 parts of surfactant, 3 parts of catalyst, 3.75 parts of water, 17 parts of foaming agent and 145 parts of isocyanate;
[0058] The polyether polyol is formed by copolymerizing propylene oxide and 4-butylbenzene-1,2-diamine using 4-butylbenzene-1,2-diamine as an initiator;
[0059] The surfactant is silicone oil AK88310 and silicone oil UR5981, wherein the mass ratio of silicone oil AK88310 to silicone oil UR5981 is 1:1;
[0060] The foaming catalyst is composed of pentamethyldiethylenetriamine, gel catalyst BX6212, and 2-hydroxy-N,N,N-trimethyl-1-propylamine formate, wherein the mass ratio of pentamethyldiethylenetriamine, gel catalyst BX6212, and 2-hydroxy-N,N,N-trimethyl-1-propylamine formate is 1:1:1;
[0061] The foaming agent is composed of cyclopentane and n-butane, wherein the mass ratio of cyclopentane to n-butane is 7.5:1;
[0062] The isocyanate is polymethylene polyphenyl isocyanate.
[0063] Example 2
[0064] A foaming material, compared with Example 1, the difference is that: the number of parts of each component is different;
[0065] In this embodiment 2, the foaming material includes, by weight, 85 parts of polyether polyol, 3 parts of surfactant, 1 part of catalyst, 2.5 parts of water, 15 parts of foaming agent and 140 parts of isocyanate.
[0066] Example 3
[0067] A foaming material, compared with Example 1, the difference is that: the number of parts of each component is different;
[0068] In this embodiment 3, the foaming material includes, by weight, 93 parts of polyether polyol, 5 parts of surfactant, 5 parts of catalyst, 5 parts of water, 19 parts of foaming agent and 150 parts of isocyanate.
[0069] Example 4
[0070] A foaming material, compared with Example 1, the difference is that: the polyether polyol is Puranol RF8310 (PolyOne).
[0071] Example 5
[0072] A foaming material, compared with Example 1, differs in that: the foaming agent consists only of cyclopentane.
[0073] Example 6
[0074] A foaming material, compared with Example 1, differs in that: the foaming agent is composed of n-butane only.
[0075] Comparative Example 1
[0076] A foaming material, compared with Example 1, the difference is that: the proportions of polyether polyol and isocyanate are different, and the proportions of other components are the same;
[0077] In Comparative Example 1, the foaming material includes 80 parts of polyether polyol and 160 parts of isocyanate, based on parts by weight.
[0078] Comparative Example 2
[0079] A foaming material, compared with Example 1, the difference is that: the proportions of polyether polyol and isocyanate are different, and the proportions of other components are the same;
[0080] In Comparative Example 2, the foaming material includes 100 parts of polyether polyol and 130 parts of isocyanate, in parts by weight.
[0081] The foaming materials of Examples 1-6 of the present application and Comparative Examples 1-2 were tested, and the testing method was as follows: after mixing the components of the foaming material, the mixture was injected into the mold (refrigerator body) using a gun tip at an injection pressure of 135 bar, and the polyether polyol and isocyanate reacted to form polyurethane rigid foam, and then the parameters such as the molding density, thermal conductivity, and deformation rate of the polyurethane rigid foam were measured.
[0082] (1) Molding density (kg / m 3): Molded density is the density of the foam in the mold excluding the skin, measured according to ASTM D 1622-88.
[0083] (2) Deformation rate (%): measured according to the test method for dimensional stability of rigid foam plastics GB / T 8811-2008.
[0084] (3) Thermal conductivity (mW / m·K): Measured at an average temperature of 10°C (upper plate 2°C, lower plate 18°C) using an EKO HC-074-200 thermal conductivity meter according to ISO 12939-01 / DIN 52612. Foam samples were cut from the center of the molded part 24 hours after the foam was prepared, and the samples were measured immediately after cutting.
[0085] The test results are shown in Table 1.
[0086] Table 1
[0087]
[0088] It can be seen from Table 1 that the molding density of the foaming materials of Examples 1-6 is less than the molding density of the foaming materials of Comparative Examples 1-2, and the thermal conductivity of the foaming materials of Examples 1-6 is less than the thermal conductivity of the foaming materials of Comparative Examples 1-2. It is known that the difference between Examples 1-6 of the present application and Comparative Examples 1-2 is that in Examples 1-6 of the present application, the number of parts of polyether polyol is 85-93 parts, and the number of parts of isocyanate is 140-150 parts, while the numbers of parts of polyether polyol and isocyanate in Comparative Examples 1 and 2 are both beyond the above ranges, which means that when polyether polyol and isocyanate are mixed and foamed according to a mass ratio of (85-93): (140-150), the obtained foaming material has a smaller molding density and a lower thermal conductivity, thereby being able to improve the thermal insulation effect of the refrigerator and reduce the production cost of the refrigerator.
[0089] Comparing Examples 1-3 with Example 4, it can be seen that the molding density of the foaming materials of Examples 1-3 is less than the molding density of the foaming material of Example 4, and the thermal conductivity of the foaming materials of Examples 1-3 is less than the thermal conductivity of the foaming material of Example 4. It is known that the difference between Examples 1-3 of the present application and Example 4 is that in Examples 1-3 of the present application, the polyether polyol is formed by copolymerizing propylene oxide and 4-butylbenzene-1,2-diamine with 4-butylbenzene-1,2-diamine as an initiator, while the polyether polyol in Example 4 is Puranol RF8310. This shows that compared with the existing polyether polyols, the polyether polyol formed by copolymerizing propylene oxide and 4-butylbenzene-1,2-diamine with 4-butylbenzene-1,2-diamine as an initiator used in Examples 1-3 of the present application can more effectively reduce the molding density and thermal conductivity of the foaming material.
[0090] Comparing Examples 1-3 with Examples 5-6, it can be seen that the molding density of the foaming materials of Examples 1-3 is lower than the molding density of the foaming materials of Examples 5-6, and the thermal conductivity of the foaming materials of Examples 1-3 is lower than the thermal conductivity of the foaming materials of Examples 5-6. It is known that the difference between Examples 1-3 of the present application and Examples 5-6 is that in Examples 1-3 of the present application, the foaming agent is composed of cyclopentane and n-butane in a mass ratio of 7.5:1, while the foaming agent in Example 5 is composed of only a single cyclopentane, and the foaming agent in Example 6 is composed of only a single n-butane. This shows that when the foaming agent is composed of cyclopentane and n-butane, the molding density and thermal conductivity of the foaming material can be more effectively reduced.
[0091] In addition, it can be seen from Table 1 that the deformation rates of the foamed materials of Examples 1-6 are all lower than 5%, which indicates that the foamed materials of Examples 1-6 of the present application have good dimensional stability.
[0092] The foaming material and refrigeration device provided in the embodiments of the present application are described in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the present application. At the same time, for those skilled in the art, according to the idea of the present application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present application.
Claims
1. A foaming material, characterized in that: In parts by weight, the foaming material comprises: 85-93 parts of polyether polyol, 3-5 parts of surfactant, 1-5 parts of catalyst, 2.5-5 parts of water, 15-19 parts of foaming agent and 140-150 parts of isocyanate.
2. The foam material according to claim 1, characterized in that: The polyether polyol is formed by copolymerizing propylene oxide and 4-butylbenzene-1,2-diamine using 4-butylbenzene-1,2-diamine as an initiator; and / or, The hydroxyl value of the polyether polyol is 540 mg KOH / g to 560 mg KOH / g, the viscosity of the polyether polyol is 5100 mPa.s to 5300 mPa.s, the pH value of the polyether polyol is 5 to 7, and the relative density of the polyether polyol is 1.1 to 1.
2.
3. The foam material according to claim 1, characterized in that: The surfactant comprises silicone oil; and / or, The isocyanate includes polymethylene polyphenyl isocyanate.
4. The foam material according to claim 3, characterized in that: The surfactant includes at least one of silicone oil AK88310 and silicone oil B8496 and at least one of silicone oil UR5981 and silicone oil UR-5961; and / or, The viscosity of the polymethylene polyphenyl isocyanate is 180 mPa·s to 220 mPa·s, and the isocyanate content of the polymethylene polyphenyl isocyanate is 30 wt % to 32.2 wt %.
5. The foaming material according to any one of claims 1 to 4, characterized in that: The foaming agent comprises at least one of cyclopentane and n-butane; and / or, The catalyst includes at least one of a foaming catalyst, a gelling catalyst and a trimerization catalyst.
6. The foam material according to claim 5, characterized in that: When the foaming agent consists of cyclopentane and n-butane, the mass ratio of the cyclopentane to the n-butane is (7-8):1; and / or, When the catalyst consists of a foaming catalyst, a gel catalyst and a trimerization catalyst, the mass ratio of the foaming catalyst, the gel catalyst and the trimerization catalyst is (0.8-1.2):(0.8-1.2):(0.8-1.2).
7. The foam material according to claim 5, characterized in that: The foaming catalyst includes pentamethyldiethylenetriamine, the gelling catalyst includes at least one of BX6212 and BX6211B, and the trimerization catalyst includes 2-hydroxy-N,N,N-trimethyl-1-propylamine formate.
8. A refrigeration device, characterized in that: It comprises a heat-insulating layer, wherein the heat-insulating layer comprises the foaming material according to any one of claims 1 to 7.
9. The refrigeration device according to claim 8, characterized in that: The refrigeration device comprises a box body, which comprises a shell and a box liner which are spaced apart from each other. The box liner is arranged on the inner side of the shell body, and the heat-insulating layer is arranged between the shell body and the box liner.
10. The refrigeration device according to claim 8, characterized in that: The refrigeration device comprises a door body, and the door body comprises a door panel and a door liner which are arranged at intervals, and the heat-insulating layer is arranged between the door panel and the door liner.