HEAT INSULATING MATERIAL AND REFRIGERATOR

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of International Application No. PCT/KR2025/014840 designating the United States, filed on Sep. 23, 2025, in the Korean Intellectual Property Receiving Office and claiming priority to Korean Patent Application No. 10-2024-0138063, filed on Oct. 10, 2024, in the Korean Intellectual Property Office, the disclosures of each of which are incorporated by reference herein in their entireties.

BACKGROUND

Field

The disclosure relates to an improved heat insulating material and a refrigerator.

Description of Related Art

Heat insulating materials are used to retain heat or block heat transfer. For example, heat insulating materials may be used in refrigerators to insulate the interior of a storage compartment from the outside.

Typically, polyurethane foam is used as an insulating material in refrigerators. Vacuum insulation panels (VIPs), which have lower thermal conductivity than polyurethane foam, have been proposed for use in refrigerators. Using VIPs in refrigerators can reduce the wall thickness of the refrigerator and increase its effective storage capacity.

However, vacuum insulation panels can only be manufactured in simple shapes such as rectangular parallelepipeds. Therefore, they may be difficult to apply to components with complex structures, such as a dyke of a refrigerator.

SUMMARY

Embodiments of the disclosure provide a heat insulating material applicable to components having complex structures.

Embodiments of the disclosure provide a heat insulating material including xenon gas.

Embodiments of the disclosure provide a heat insulating material including a plurality of partition layers to prevent and/or reduce natural convection that may occur internally.

Embodiments of the disclosure provide a refrigerator capable of reducing the amount of heat transferred from the outside to the inside of a storage compartment through a dyke.

A heat insulating material according to an example embodiment of the disclosure may include: an envelope defining a storage space and configured to store gas therein; a first partition layer arranged inside the envelope, configured to divide the storage space in one direction; and a second partition layer arranged inside the envelope and spaced apart from the first partition layer in the one direction, the second partition layer configured to divide the storage space into a plurality of sections together with the first partition layer.

A heat insulating material according to an example embodiment may include: an envelope defining a storage space and configured to store gas therein; and a plurality of partition layers arranged in one direction inside the envelope, configured to divide the storage space, wherein a distance between two adjacent partition layers among the plurality of partition layers in the one direction is 10.4 mm or less.

A refrigerator according to an example embodiment may include: a main body in which a storage compartment is arranged; a door configured to open and close the storage compartment; a door basket arranged on a rear surface of the door; and a dyke arranged along an edge of the rear surface of the door and configured to support the door basket. The dyke may include an envelope configured to form a storage space and to store gas therein; and a plurality of partition layers arranged inside the envelope and spaced apart from each other along a heat transfer path from outside the storage compartment toward the inside of the storage compartment, to divide the storage space.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view illustrating an example heat insulating material according to various embodiments;

FIG. 2 is a diagram illustrating an enlarged view of area A shown in FIG. 1 according to various embodiments;

FIG. 3 is a cross-sectional view taken along line B-B′ in FIG. 1 according to various embodiments;

FIG. 4 is a cross-sectional an arbitrary partition layer and arbitrary space according to various embodiments;

FIG. 5 is a cross-sectional view illustrating an example heat insulating material according to various embodiments;

FIG. 6 is a cross-sectional view illustrating a heat insulating material according to various embodiments;

FIG. 7 is a cross-sectional view illustrating an example heat insulating material according to various embodiments;

FIG. 8 is a perspective view illustrating an example refrigerator according to various embodiments;

FIG. 9 is a cross-sectional view of a dyke and adjacent structures of a refrigerator according to various embodiments.

DETAILED DESCRIPTION

Example embodiments described in the present disclosure and the configurations shown in the drawings are merely examples, and various modifications to the various example embodiments and drawings at the time of filing of the present application are possible.

The same reference numerals or signs used in the drawings of the present disclosure indicate components or elements that perform substantially the same function.

The terms used in the present disclosure are intended to describe various example embodiments, and not to limit or restrict the disclosure. Singular expressions may include plural forms unless clearly indicated otherwise in the context. As used herein, the terms “include” or “have,” and the like, are intended to specify the presence of stated features, numbers, steps, operations, components, parts, or combinations thereof, and do not preclude the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

The terms such as “first,” “second,” etc., used herein may be employed to describe various components, but such components are not limited by these terms. These terms may be used to distinguish one component from another. For example, without departing from the scope of the present disclosure, a first component may be referred to as a second component, and similarly, a second component may be referred to as a first component. The term “and/or” includes a combination of two or more of the listed items or any one of the listed items.

Terms such as “front,” “rear,” “left,” “right,” “upper,” and “lower,” used in the following description, do not limit the shapes or positions of the components.

When a component is described as being “connected,” “coupled,” “supported,” or “in contact” with another component, it includes not only cases where the components are directly connected, coupled, supported, or in contact with each other, but also cases where they are indirectly connected, coupled, supported, or in contact with each other through a third component.

When a component is described as being “on” another component, it includes not only cases where the component is in contact with the other component, but also cases where another component is interposed between the two components.

Hereinafter, various example embodiments according to the present disclosure will be described in greater detail with reference to the accompanying drawings.

FIG. 1 illustrates is a cross-sectional view illustrating an example heat insulating material according to various embodiments. FIG. 2 is an enlarged view of area A shown in FIG. 1 according to various embodiments. FIG. 3 is a cross-sectional view taken along line B-B′ in FIG. 1 according to various embodiments.

Referring to FIGS. 1, 2 and 3, a heat insulating material 1 may include an envelope 10. A storage space 11 may be formed inside the envelope 10. The storage space 11 may be a sealed space separated from the outer space of the envelope 10. There is no particular limitation on the shape of the envelope 10.

The envelope 10 may include a material such as polyethylene terephthalate (PET). However, the material of the envelope 10 is not particularly limited.

Gas may be stored inside the envelope 10. In other words, gas may be stored in the storage space 11 of the envelope 10. The gas may refer to any substance provided in a gaseous state.

One of the main causes of heat conduction is the collision of adjacent molecules. Adjacent molecules may diffuse their internal energy through mutual collision.

When a substance is in a gaseous state, the molecules of the substance may be relatively spaced farther apart from each other. Accordingly, the frequency of collisions between adjacent molecules may be lower than that in the case where the substance is in a liquid or solid state. Due to this property, substances in a gaseous state may have relatively low thermal conductivity.

For example, the gas stored in the storage space 11 of the envelope 10 may include a gas including a substance having relatively low thermal conductivity. For example, the gas stored in the storage space 11 may include xenon gas. For example, the proportion of xenon gas in the storage space 11 may be 99 mol % or more.

Xenon gas is an inert gas with weak intermolecular forces and may have a relatively very low thermal conductivity. For example, the thermal conductivity Kxe of xenon gas may be 5.6 mW/mK.

According to an embodiment of the present disclosure, since xenon gas is stored in the storage space 11 of the envelope 10, the heat insulating material 1 may have a relatively very low thermal conductivity.

The gas may be injected into the storage space 11 under atmospheric pressure. Through this process, inflow of substances other than xenon gas into the storage space 11 may be minimized and/or reduced.

The heat insulating material 1 may include a partition layer 20. The partition layer 20 may be arranged inside the envelope 10. For example, the partition layer 20 may be integrally formed with the envelope 10.

The partition layer 20 may divide the storage space 11. That is, the partition layer 20 may divide the storage space 11 into a plurality of separate spaces 11a, 11b, 11c.

The partition layer 20 may have a thickness that is very small compared to the overall width (in the Y direction) of the heat insulating material 1. For example, the overall width of the heat insulating material 1 may be 20 mm or more, and the thickness of the partition layer 20 may be 0.05 mm.

The partition layer 20 may be provided in plurality. For example, the plurality of partition layers 20 may include a first partition layer 20a and a second partition layer 20b. However, the number of partition layers 20 is not particularly limited. For convenience of explanation, an example embodiment in which only two partition layers 20 are arranged will be described below.

The plurality of partition layers 20 may divide the storage space 11 in one direction. For example, the first partition layer 20a and the second partition layer 20b may each divide the storage space 11 in one direction. For example, the first partition layer 20a and the second partition layer 20b may divide the storage space 11 in a first direction D1, which is the same as the width direction (Y direction) of the envelope 10.

Each of the plurality of partition layers 20 may extend in a direction intersecting with the one direction to divide the storage space 11 in the one direction. For example, the first partition layer 20a and the second partition layer 20b may each extend in a second direction D2 (X direction) intersecting with the first direction D1, thereby dividing the storage space 11 in the first direction D1.

To divide the storage space 11 in one direction, the plurality of partition layers 20 may be arranged spaced apart from each other in the one direction. For example, the first partition layer 20a and the second partition layer 20b may be spaced apart from each other in the first direction D1, thereby dividing the storage space 11 into a first space 11a, a second space 11b, and a third space 11c sequentially arranged along the first direction D1. Although FIG. 1 shows that the two partition layers 20 divide the storage space 11 into three spaces 11a, 11b, 11c, the number of divided spaces may vary depending on the number of partition layers 20.

The one direction in which the plurality of partition layers 20 are arranged may be the same as the direction in which heat is transferred inside the heat insulating material 1. In other words, the direction in which the spaces divided by the plurality of partition layers 20 are arranged may be the same as the direction in which heat is transferred inside the heat insulating material 1. For example, the first direction D1, in which the first partition layer 20a and the second partition layer 20b are arranged, or the first direction D1, in which the first space 11a, the second space 11b, and the third space 11c are arranged, may be the same as the direction in which heat is transferred inside the heat insulating material 1. With this configuration, the amount of heat transferred along the one direction inside the heat insulating material 1 may be reduced. This will be described in greater detail below.

As described above, the gas stored in the storage space 11 may include xenon gas. Since xenon gas is in a gaseous state, there is a possibility that natural convection of the xenon gas may occur within the storage space 11. For example, when a temperature difference occurs inside the storage space 11, natural convection of the xenon gas may occur, and heat may be transferred from a high-temperature region to a low-temperature region.

According to an embodiment of the present disclosure, the plurality of partition layers 20 divides the storage space 11, so the width (Y direction) of each divided space may be narrower than the overall width (Y direction) of the storage space 11. For example, as the first partition layer 20a and the second partition layer 20b divide the storage space 11 into the first space 11a, the second space 11b, and the third space 11c, the widths W1, W2, W3 of each of the spaces 11a, 11b, 11c may be narrower than the overall width of the storage space 11. In this case, the flow of the gas stored in the storage space 11 may be restricted, and natural convection of the xenon gas may be primarily suppressed. This will be described in greater detail below.

According to an embodiment of the present disclosure, since the direction in which the spaces divided by the plurality of partition layers 20 are arranged is the same as the direction in which heat is transferred inside the heat insulating material 1, a temperature difference occurring inside each divided space may be smaller than a temperature difference occurring inside the entire storage space 11. For example, a temperature difference occurring inside each of the first space 11a, the second space 11b, and the third space 11c may be smaller than a temperature difference occurring inside the entire storage space 11. Accordingly, natural convection of xenon gas caused by a temperature difference inside the storage space 11 may be secondarily suppressed.

Each of the plurality of partition layers 20 may include a base layer 21 and a coating layer 22 formed by coating aluminum on the base layer 21.

The base layer 21 may include a material through which gas-phase substances cannot pass. For example, the base layer 21 may include a material provided in the form of closed-cell foam.

Referring to FIG. 2, the closed-cell foam may be a material in which a plurality of cells (or pores) is formed inside. Each of the cells is formed independently and sealed, so they may not be connected to each other. For example, it may be difficult for substances to move between cells. Accordingly, gas may not pass through the base layer 21.

Each of the plurality of cells may be formed in a vacuum state or may include a gas-phase substance therein. Therefore, compared to a case in which no cells are formed in the base layer 21, when the base layer 21 includes a material in the form of closed-cell foam, the thermal conductivity may be relatively lower.

According to an embodiment of the present disclosure, as the base layer 21 includes a material formed in the form of closed-cell foam, xenon gas may be blocked from passing through the partition layer 20, and the thermal conductivity of the heat insulating material 1 may be relatively reduced.

The base layer 21 may include a PET (Polyethylene terephthalate) material. However, there is no particular limitation on the material of the base layer 21.

The coating layer 22 may be configured to prevent and/or reduce heat transfer by thermal radiation. That is, the coating layer 22 may be configured to block the transfer of heat in the form of electromagnetic waves from a high-temperature region. For example, the coating layer 22 may reflect electromagnetic waves generated in a high-temperature region to block heat transfer.

According to an embodiment of the present disclosure, the coating layer 22 may be formed by aluminum coating. Since aluminum has a relatively high reflectivity for thermal radiation, it may effectively reflect electromagnetic waves generated in a high-temperature region. For example, when a material has a temperature of 30° C., it may emit electromagnetic waves with a wavelength of approximately 0.0095 mm via thermal radiation, and aluminum may have a reflectivity of 95% for electromagnetic waves having such a wavelength. Since the heat insulating material 1 includes a plurality of partition layers 20, the effect of thermal radiation reflection may be further enhanced.

The coating layer 22 may be arranged on one surface of the base layer 21. For example, the base layer 21 may include a first surface 211 and a second surface 212 that is opposite to the first surface 211 and located farther than the first surface 211 with respect to a first direction D1, and the coating layer 22 may be arranged on the first surface 211.

As described above, heat may be transferred inside the heat insulating material 1 along the first direction D1. Therefore, in each of the plurality of spaces 11a, 11b, 11c, heat may also be transferred along the first direction D1. Specifically, each of the spaces 11a, 11b, 11c may include a region on one side where the coating layer 22 is not formed, and a region on the other side, opposite to the one side with respect to the first direction D1, where the coating layer 22 is formed, and heat may be transferred from the region on the one side toward the region on the other side. That is, the region on the one side may have a higher temperature than the region on the other side.

In this case, electromagnetic waves emitted from the region on the one side may be reflected by the coating layer 22 arranged in the region on the other side. Accordingly, heat transfer from the one side to the other side by thermal radiation may be prevented/reduced.

However, the coating layer 22 is not necessarily limited to being arranged only on the first surface 211 of the base layer 21. For example, the coating layer 22 may be arranged on both surfaces 211 and 212 of the base layer 21.

The coating layer 22 may cover most of one surface of the base layer 21. For example, the area of the coating layer 22 may be 90% or more of the area of the base layer 21. With such a configuration, the thermal radiation reflection efficiency of the coating layer 22 may be further improved. However, there is no particular limitation on the area of the coating layer 22.

An edge of the coating layer 22 may be arranged to be spaced apart from the envelope 10. For example, the coating layer 22 may not be in contact with the inner surface of the envelope 10.

Aluminum may have a relatively high thermal conductivity. For example, the thermal conductivity of aluminum may be 237 W/mK. Therefore, if the coating layer 22 formed by aluminum coating is in contact with the inner surface of the envelope 10, heat transfer from a high-temperature region outside the heat insulating material 1 to a low-temperature region may occur through the coating layer 22.

According to an embodiment of the present disclosure, by allowing the edge of the coating layer 22 to be spaced apart from the envelope 10, the coating layer 22 may not be in contact with the inner surface of the envelope 10, and heat transfer through the coating layer 22 may be prevented/reduced.

The above has described the configuration of the heat insulating material 1. For example, the heat insulating material 1 may include the envelope 10, xenon gas stored in a storage space 11 inside the envelope 10, and a plurality of partition layers 20 that divide the storage space 11 inside the envelope 10. For example, most of the storage space 11 of the envelope 10 may be filled with xenon gas.

Since xenon gas is a substance in a gaseous state, it may have a relatively low density. Since each base layer 21 of the plurality of partition layers 20 includes a material formed in the form of closed-cell foam, it may also have a relatively low density. Accordingly, the heat insulating material 1 may have a relatively very low density. For example, the density of the heat insulating material 1 may be about 20 kg/m³ or less.

Since xenon gas is in a gaseous state, the design limitation on the shape of the envelope 10 that stores xenon gas may be relatively reduced. In other words, even if the envelope 10 has a complex shape, it may still be relatively easy to fill it with xenon gas and to form a plurality of partition layers 20 inside. Therefore, the heat insulating material 1 may be applicable to components having complex structures.

For example, the heat insulating material 1 may be applied to a dyke of a refrigerator. This will be described in greater detail below.

FIG. 4 is a cross-sectional view illustrating an example arbitrary partition layer and an arbitrary space according to various embodiments.

As described above, when at least some of the plurality of partition layers 20 divide the storage space 11 into a plurality of spaces 11a, 11b, 11c, the width (in the Y direction) of each space 11a, 11b, 11c may be relatively narrow. In other words, the distance between two adjacent partition layers 20 arranged along the first direction D1 may be relatively short. If the widths of the spaces 11a, 11b, 11c are reduced below a certain level, the occurrence of natural convection in each space 11a, 11b, 11c may be prevented/reduced (see FIGS. 1 to 3).

With reference to FIG. 4, the range of the width that may be provided in each of the plurality of spaces 11a, 11b, 11c divided by the plurality of partition layers 20 will be described in more detail. For the convenience of calculation, it is assumed that one arbitrary partition layer 20c and one arbitrary space 11d in which xenon gas is stored are arranged in the first direction D1. It is also assumed that the width (in the X direction) of each of the arbitrary partition layer 20c and the arbitrary space 11d in the second direction D2 is provided to be below a certain value, so that the occurrence of natural convection of xenon gas is determined only by the width W4 (in the Y direction) of the arbitrary space 11d in the first direction D1. In this case, the arbitrary partition layer 20c may include a base layer 21c and a coating layer 22c. In addition, the thickness and thermal conductivity of the envelope 10 are ignored for the convenience of calculation.

In general, the Rayleigh number (Ra) is used to determine whether a specific fluid causes natural convection. It is known that when Ra is 1700 or less, natural convection does not occur.

The method for calculating the Rayleigh number Ra_xe of xenon gas stored in the arbitrary space 11d is as follows. In this case, the type of gas is assumed to be xenon gas.

R ⁢ a x ⁢ e = ( g * β * Δ ⁢ T * L ^ 3 ) / ( v * α )

The g refers to gravitational acceleration, with a value of 9.81 m/s². The β refers to the thermal expansion coefficient of the gas, with a value of 1/300 K. The ΔT refers to the temperature difference within the arbitrary space 11d, which is assumed to be 10 K for thermal insulation performance. The L corresponds to the width (Y direction) of the arbitrary space 11d in the first direction D1. The ν refers to the kinematic viscosity of xenon, with a value of 2.4×10⁻⁵ m²/s. The α refers to the thermal diffusivity of the gas, with a value of 1/300 K.

The above equation can be rearranged for L as follows:

L = ( ( Ra x ⁢ e * v * α ) / ( g * β * Δ ⁢ T ) ) ^ ( 1 / 3 )

Using the above equation, L can be calculated based on a given Ra_xe. For example, when Ra_xe is 1700, L is 10.4 mm. In other words, when Lis 10.4 mm, Ra_xe is 1700. Since Ra_xe is proportional to L³, if L is greater than 10.4 mm, Ra_xe may exceed 1700. In such a case, convection of xenon gas may occur.

In general, when a specific fluid causes natural convection, the Nusselt number (Nu) is used to calculate the resulting thermal conductivity. Specifically, the thermal conductivity K_co due to convection can be calculated using the equation K_co=Nu*K_xe. The K_xe refers to the thermal conductivity of xenon gas, with a value of 5.6 mW/mK.

Nu can be determined based on the Rayleigh number Ra_xe of xenon gas. For example, when Ra_xe falls within the range of 1043 Ra_xe≤109, Nu can be calculated using the equation Nu=0.59*Ra_xe∧0.25.

Table 1 below shows the Ra_xe, Nu, and K_co according to L.

	TABLE 1
	L(mm)	Raxe	Nu	Kco(mW/mK)

	20	11918	6.16	34.742
	30	40224	8.36	47.150
	40	95347	10.36	58.430

Referring to Table 1, it can be seen that when L is greater than 10.4 mm, the thermal conductivity K_co increases significantly as L increases.

When L is equal to or less than 10.4 mm, the Rayleigh number Ra_xe may be equal to or less than 1700. In this case, convection of xenon gas may not occur.

However, even when L is equal to or less than 10.4 mm, heat transfer may still occur through thermal conduction by xenon gas stored in the arbitrary partition layer 20c or the arbitrary space 11d. In addition, since the arbitrary partition layer 20c and the arbitrary space 11d are arranged along the first direction D1, the thermal conductivity in the first direction D1 and the second direction D2 may be different from each other.

The thermal conductivity in the first direction D1 and the second direction D2 will be examined respectively.

The thermal conductivity in the first direction D1 will be examined.

When the arbitrary partition layer 20c and the arbitrary space 11d are arranged in the first direction D1 and have the same width in the second direction D2 (X direction), the thermal resistance R_D1 in the first direction D1 satisfies the equation R_D1=R_s+R_xe. Here, the thermal resistance R can be calculated using the formula R=t/K, where t refers to the thickness of the component, and K refers to the thermal conductivity of the component. R_s and R_xe correspond to the thermal resistances of the arbitrary partition layer 20c and the xenon gas in the arbitrary space 11d, respectively. The equation for R_D1 can be rearranged as follows:

t t ⁢ otal / K 1 = t s / K s + L / K x ⁢ e

The t_total corresponds to the sum of the thickness of the arbitrary partition layer 20c and the width of the arbitrary space 11d, and the K₁ refers to the thermal conductivity of the partition layer 20c and the xenon gas in the first direction D1. The t_s is the thickness of the partition layer 20c, and the K_s is the thermal conductivity of the partition layer 20c. The L is the width (in the Y direction) of the arbitrary space 11d in the first direction D1, and K_we is the thermal conductivity of xenon gas. In this case, t_total can be replaced with t_s+L.

When the equation is rearranged with respect to K₁, and t_total is replaced with t_s+L, the following equation is obtained:

K 1 = ( t s + L ) / ( ( t s / K s ) + ( L / K x ⁢ e ) )

In this equation, t_s is assumed to be 0.05 mm. Also, assuming that the base layer 21c of the arbitrary partition layer 20c includes PET material formed in the form of closed-cell foam, K_s is 40 mW/mK. In addition, K_xe is 5.6 mW/mK. Based on this equation, K₁ can be calculated according to the value of L.

Table 2 below shows the K₁ according to L.

	TABLE 2
	L(mm)	K1 (mW/mK)

	0.5	6.128
	1	5.891
	2	5.771
	5	5.698
	10	5.674
	10.4	5.673
	20	5.662
	30	5.658
	40	5.656

Referring to Table 2, it can be seen that as L decreases, K_co increases.

The thermal conductivity in the second direction D2 will be examined.

When the arbitrary partition layer 20c and the arbitrary space 11d are arranged in the first direction D1 and have the same width in the second direction D2 (X direction), the thermal conductivity K₂ in the second direction D2 can be calculated using the following equation:

K 2 * t t ⁢ otal = K s * t s + K x ⁢ e * L

The t_total corresponds to the sum of the thickness of the arbitrary partition layer 20c and the width of the arbitrary space 11d, and the K₂ refers to the thermal conductivity in the second direction D2 of the partition layer 20c and the xenon gas. The t_s is the thickness of the arbitrary partition layer 20c, and the K_s is the thermal conductivity of the partition layer 20c. The L corresponds to the width (Y direction) of the arbitrary space 11d in the first direction D1, and K_xe is the thermal conductivity of xenon gas. In this case, t_total can be replaced with t_s+L.

Rearranging the above equation for K₂ and substituting t_total with t_s+L yields the following equation.

K 2 = ( K s * t s + K x ⁢ e * L ) / ( t s + L )

In this equation, t_s is assumed to be 0.05 mm. Also, assuming that the base layer 21c of the arbitrary partition layer 20c includes PET material formed in the form of closed-cell foam, K_s is 40 mW/mK. In addition, K_xe is 5.6 mW/mK. Using this equation, K₂ can be calculated according to the value of L.

Table 3 below shows the K₂ according to L.

	TABLE 3
	L(mm)	K2(mW/mK)

	0.5	8.773
	1	7.286
	2	6.488
	5	5.990
	10	5.821
	10.4	5.814
	20	5.736
	30	5.707
	40	5.693

In the above, both the case in which heat is transferred by natural convection of xenon gas stored in the arbitrary space 11d and the case in which heat is transferred by thermal conduction through the arbitrary partition layer 20c or the xenon gas have been examined. The total thermal conductivity K_D1 in the first direction D1 and the total thermal conductivity K_D2 in the second direction D2 must each be derived by assuming both of the above cases. For example, K_D1 can be calculated using the equation K_D1=K₁+K_co, and K_D2 can be calculated using the equation K_D2=K₂+K_co. Table 4 below shows K_D1 according to different values of L.

Table 4 below shows the K_D1 according to L.

	TABLE 4
	L(mm)	K1(mW/mK)	Kco(mW/mK)	KD1(mW/mK)

	0.5	6.128	0	6.128
	1	5.891	0	5.891
	2	5.771	0	5.771
	5	5.698	0	5.698
	10	5.674	0	5.674
	10.4	5.673	0	5.673
	20	5.662	34.742	40.404
	30	5.658	47.150	52.808
	40	5.656	58.430	64.086

Table 5 below shows the K_D2 according to L.

	TABLE 5
	L(mm)	K2(mW/mK)	Kco(mW/mK)	KD2(mW/mK)

	0.5	8.773	0	8.773
	1	7.286	0	7.286
	2	6.488	0	6.488
	5	5.990	0	5.990
	10	5.821	0	5.821
	10.4	5.814	0	5.814
	20	5.736	34.742	40.478
	30	5.707	47.150	52.857
	40	5.693	58.430	64.123

According to Table 4, it can be seen that as L increases, K₁ decreases. However, when L exceeds 10.4 mm, it can be seen that the value of K_co significantly increases due to the occurrence of natural convection. That is, when L is 10.4 mm, K_D1 may have a minimum value, and that value is 5.673 mW/mK.

According to Table 5, it can be seen that K₂ also decreases as L increases. However, when L exceeds 10.4 mm, it can be seen that the value of K_co significantly increases due to the occurrence of natural convection. That is, when L is 10.4 mm, K_D2 may have a minimum value, and that value is 5.814 mW/mK.

Therefore, in order to prevent and/or reduce natural convection from occurring, L may be provided to be 10.4 mm or less.

According to Table 4, when L is 1 mm or more and 10.4 mm or less, the total thermal conductivity K_D1 in the first direction D1 may be less than 6 mW/mK. Also, according to Table 5, when L is 5 mm or more and 10.4 mm or less, the total thermal conductivity K_D1 in the first direction D1 may be less than 6 mW/mK. This is a significantly low value compared to conventional polyurethane foam-type heat insulating materials, which have a thermal conductivity level of 18 mW/mK to 20 mW/mK.

Therefore, L may be 5 mm or more and 10.4 mm or less. In particular, when L is 10.4 mm, each of K_D1 and K_D2 may be the smallest.

Even if the arbitrary partition layer 20c and the arbitrary space 11d are each provided in plurality and are arranged in the first direction D1 or the second direction D2, the total thermal conductivity value may be maintained the same.

Hereinafter, referring to FIGS. 1, 2 and 3, the widths of the respective plurality of spaces 11a, 11b, 11c will be examined again.

The respective widths W1, W2, and W3 of the plurality of spaces 11a, 11b, and 11c in the first direction D1 may be 10.4 mm or less. Preferably, the respective widths of the plurality of spaces 11a, 11b, 11c in the first direction D1 may be 5 mm or more and 10.4 mm or less. Also, as described above, the optimal value for the widths W1, W2, W3 of the plurality of spaces 11a, 11b, 11c may be 10.4 mm.

In other words, the distance between two partition layers 20 among the plurality of partition layers 20 that are arranged adjacent to each other may be 10.4 mm or less in the first direction D1. For example, the distance between two partition layers 20 among the plurality of partition layers 20 that are arranged adjacent to each other may be 5 mm or more and 10.4 mm or less in the first direction D1. The optimal value for the distance between two partition layers 20 among the plurality of partition layers 20 that are arranged adjacent to each other in the first direction D1 may be 10.4 mm.

Therefore, the plurality of partition layers 20 may be arranged spaced apart from each other by 10.4 mm such that the widths of as many of the plurality of spaces 11a, 11b, 11c as possible become 10.4 mm. For example, when the total width of the storage space 11 is 30 mm, the widths W1, W2 of the first space 11a and the second space 11b may each be 10.4 mm, and the width W3 of the third space 11c may be 9.2 mm. In this case, the thickness of each of the plurality of partition layers 20 is neglected.

However, the respective widths W1, W2, W3 of the plurality of spaces 11a, 11b, 11c may also be equal to each other. Hereinafter, referring to FIG. 5, the above-described example embodiment will be examined in greater detail.

FIG. 5 is a cross-sectional view illustrating an example heat insulating material according to various embodiments.

Referring to FIG. 5, a heat insulating material 2 according to an embodiment of the present disclosure will be described. In describing the heat insulating material 2, the same reference numerals are assigned to components that are substantially the same as those illustrated in FIGS. 1, 2, 3 and 4, and detailed descriptions thereof may not be repeated here.

Referring to FIG. 5, the heat insulating material 2 may include an envelope 10. A storage space 11 may be formed inside the envelope 10.

A plurality of partition layers 20 may divide the storage space 11 in one direction. For example, each of a first partition layer 20a and a second partition layer 20b may divide the storage space 11 in a first direction D1, which is the same as the width direction (Y direction) of the envelope 10. Accordingly, the storage space 11 may be divided into a first space 11a′, a second space 11b′, and a third space 11c′, which are sequentially arranged along the first direction D1.

Each of the plurality of spaces 11a′, 11b′, 11c′ may have the same width (Y direction) (W1′, W2′, W3′). That is, regardless of the total width of the storage space 11, the widths W1′, W2′, W3′ of the first space 11a′, the second space 11b′, and the third space 11c′, respectively, may be equal to one another. Even in this case, the widths W1′, W2′, W3′ of the plurality of spaces 11a′, 11b′, 11c′, respectively, may be 5 mm or more and 10.4 mm or less. For example, when the total width of the storage space 11 is 30 mm, the widths W1, W2, W3 of the first space 11a, the second space 11b, and the third space 11c may each be 10 mm.

FIG. 6 is a cross-sectional view illustrating an example heat insulating material according to various embodiments.

Hereinafter, with reference to FIG. 6, a heat insulating material 3 according to an embodiment of the present disclosure will be described. In describing the heat insulating material 3, the same reference numerals are assigned to components that are substantially the same as those illustrated in FIGS. 1, 2, 3 and 4, and detailed descriptions thereof may not be repeated here.

The heat insulating material 3 may include a plurality of partition layers 20′. Each of the plurality of partition layers 20′ may be arranged inside the envelope 10.

The plurality of partition layers 20′ may divide the storage space 11 in one direction. For example, the plurality of partition layers 20′ may divide the storage space 11 in a second direction D2, which is the same as the length direction (X direction) of the envelope 10.

Each of the plurality of partition layers 20′ may extend in a direction intersecting with the one direction in order to divide the storage space 11 in the one direction. For example, each of the plurality of partition layers 20′ may extend in a first direction D1 (Y direction) that intersects with the second direction D2, thereby dividing the storage space 11 in the second direction D2.

The plurality of partition layers 20′ may be arranged spaced apart from each other in the one direction to divide the storage space 11 in the one direction. For example, the plurality of partition layers 20′ may be arranged spaced apart from each other in the second direction D2, thereby dividing the storage space 11 into a plurality of spaces sequentially arranged along the second direction D2.

The one direction in which the plurality of partition layers 20′ are arranged may be the same as the direction in which heat is transferred inside the heat insulating material 1. For example, the second direction D2 in which the plurality of partition layers 20′ are arranged may be the same as the direction in which heat is transferred inside the heat insulating material 3. Through this configuration, the amount of heat transferred along the one direction inside the heat insulating material 3 may be reduced.

FIG. 7 is a cross-sectional view illustrating an example heat insulating material according to various embodiments.

Referring to FIG. 7, a heat insulating material 4 according to an embodiment of the present disclosure will be described. In describing the heat insulating material 4, the same reference numerals are assigned to components that are substantially the same as those illustrated in FIGS. 1, 2, 3 and 4, and detailed descriptions thereof may not be repeated here.

The heat insulating material 4 may include a plurality of partition layers 20″. Each of the plurality of partition layers 20″ may be arranged inside the envelope 10.

Some of the plurality of partition layers 20″ may divide the storage space 11 in one direction. For example, each of the first partition layer 20a and the second partition layer 20b may divide the storage space 11 in the first direction D1, which is the same as the width direction (Y direction) of the envelope 10. Accordingly, the storage space 11 may be divided into a plurality of spaces sequentially arranged along the first direction D1.

Another portion of the plurality of partition layers 20″ may divide the storage space 11 in a direction intersecting with the one direction. For example, the third partition layer 20d may divide the storage space 11 in the second direction D2, which is the same as the length direction (X direction) of the envelope 10. For example, the third partition layer 20d may divide each of the plurality of spaces divided by the first partition layer 20a and the second partition layer 20b in the second direction D2 that intersects with the first direction D1.

Some of the plurality of partition layers 20″ may extend in a direction intersecting with the one direction in order to divide the storage space 11 in the one direction. For example, each of the first partition layer 20a and the second partition layer 20b may extend in the second direction D2, which intersects with the first direction D1, thereby dividing the storage space 11 in the first direction D1.

Another portion of the plurality of partition layers 20″ may extend in the one direction in order to divide the storage space 11 in a direction intersecting with the one direction. For example, the third partition layer 20d may extend in the first direction D1, thereby dividing the storage space 11 in the second direction D2, which intersects with the first direction D1.

Some of the plurality of partition layers 20″ may be arranged spaced apart from each other in the one direction in order to divide the storage space 11 in the one direction. For example, the first partition layer 20a and the second partition layer 20b may be arranged spaced apart from each other in the first direction D1, thereby dividing the storage space 11 into a plurality of spaces sequentially arranged along the first direction D1.

Another portion of the plurality of partition layers 20″ may be arranged spaced apart from each other in a direction intersecting with the one direction in order to divide the storage space 11 in the direction intersecting with the one direction. For example, the third partition layer 20d may be arranged in plurality, and the plurality of third partition layers 20d may be arranged spaced apart from each other in the second direction D2, thereby dividing the storage space 11 into a plurality of spaces sequentially arranged along the second direction D2.

According to an embodiment of the present disclosure, the storage space 11 may be divided in one direction and also in a direction intersecting with the one direction by the plurality of partition layers 20″. For example, the storage space 11 may be divided in the first direction D1 by the first partition layer 20a and the second partition layer 20b, and simultaneously be divided in the second direction D2 by the plurality of third partition layers 20d. That is, the storage space 11 may be divided into a plurality of spaces forming a grid pattern. Through such a configuration, both the amount of heat transferred in the width direction of the envelope 10 and the amount of heat transferred in the length direction of the envelope 10 inside the heat insulating material 4 may be reduced.

Each of the first partition layer 20a, the second partition layer 20b, and the third partition layer 20d may be arranged in plurality. For example, there is no particular limitation on the number of partition layers 20″ arranged in the first direction D1 or the second direction D2. Also, an embodiment in which one partition layer 20″ is arranged in the first direction D1 and one partition layer 20″ is arranged in the second direction D2 is also possible.

FIG. 8 is a perspective view illustrating an example refrigerator according to various embodiments. FIG. 9 is a cross-sectional view of a dyke and adjacent structures of a refrigerator according to various embodiments.

In the above, the heat insulating materials 1, 2, 3, 4 according to an embodiment of the present disclosure have been described. Hereinafter, an example in which the configuration of the heat insulating materials 1, 2, 3, 4 according to an embodiment of the present disclosure is applied to a refrigerator 100 will be described. In describing the refrigerator 100, the same reference numerals are assigned to components that are substantially the same as those illustrated in FIGS. 1, 2, 3, 4, 5, 6 and 7, and detailed descriptions thereof may may not be repeated here.

Referring to FIGS. 8 and 9, the refrigerator 100 may include a main body 110, storage compartments 121, 122 arranged inside the main body 110, a door 130 that opens and closes the storage compartments 121, 122, and a cooling system for supplying cold air to the storage compartments 121, 122.

The main body 110 may include an inner case 111 that forms the storage compartments 121, 122, and an outer case 112 that forms the external appearance of the refrigerator 100. The inner case 111 may be arranged inside the outer case 112. The storage compartments 121, 122 may be arranged inside the inner case 111.

The main body 110 may include a main body insulating material arranged between the inner case 111 and the outer case 112. The main body insulating material may be arranged so that the inner case 111 and the outer case 112 are thermally insulated from each other. The main body insulating material may prevent and/or reduce heat exchange between the inside of the storage compartments 121, 122 and the outside of the main body 110, thereby improving the cooling efficiency inside the storage compartments 121, 122.

As the main body insulating material, urethane foam insulation, expanded polystyrene (EPS) insulation, vacuum insulation panels, and the like may be used. However, the disclosure is not limited thereto, and the main body insulating material may be configured to include various materials. For example, a portion of the main body insulating material may be formed of the heat insulating materials 1, 2, 3, 4 according to an embodiment of the present disclosure.

Storage compartments 121, 122 may be formed inside the main body 110. The storage compartments 121, 122 may include a refrigerator compartment, which is maintained at approximately 0 to 5 degrees Celsius to store food at low temperatures, and a freezer compartment, which is maintained at approximately-30 to 0 degrees Celsius to store food in a frozen state.

Shelves 118 on which food can be placed and drawers 119 in which food can be stored may be arranged in the storage compartments 121, 122.

The refrigerator 100 may include a cooling system configured to generate cold air using a cooling cycle and to supply the generated cold air to the storage compartments 121, 122. The cooling system may generate cold air using a refrigeration cycle in which refrigerant is compressed, condensed, expanded, and evaporated. For example, the cooling system may include a compressor, a condenser, an expansion valve, an evaporator, a blowing fan, and the like.

The door 130 may be rotatably arranged with respect to the main body 110. Through this configuration, the door 130 may open and close the storage compartments 121, 122.

An outer surface 130a of the door 130 may form a part of the external appearance of the refrigerator 100. When the storage compartments 121, 122 are closed by the door 130, the outer surface 130a of the door 130 may form the front surface of the door 130.

When the storage compartments 121, 122 are closed by the door 130, a rear surface 130b of the door 130 may be configured to cover the front side of the storage compartments 121, 122. A door basket 132 for storing food may be arranged on the rear surface 130b of the door 130.

A foaming space may be formed between the outer surface 130a and the rear surface 130b of the door 130, and a door insulating material 131 may be foamed therein. The door insulating material 131 may prevent and/or reduce heat exchange between the outer surface 130a and the rear surface 130b of the door 130, thereby improving the insulation performance between the inside of the storage compartments 121, 122 and the outside of the door 130.

As the door insulating material 131, urethane foam insulation, EPS insulation, vacuum insulation panels, and the like may be used. However, the disclosure is not limited thereto, and the door insulating material 131 may be configured to include various materials. For example, a portion of the door insulating material 131 may be formed of the heat insulating materials 1, 2, 3, 4 according to an embodiment of the present disclosure.

The refrigerator 100 may include a dyke 200 configured to support the door basket 132. The dyke 200 may be arranged along the edge 130c of the rear surface 130b of the door 130. At least a portion of the dyke 200 may protrude rearward from the rear surface 130b of the door 130.

The dyke 200 may include a base portion 250. The base portion 250 may be in contact with the rear surface 130b of the door 130. The base portion 250 may extend in a direction parallel to the rear surface 130b of the door 130. Specifically, one end 250a of the base portion 250 may be formed adjacent to the edge 130c of the rear surface 130b of the door 130, and the other end 250b of the base portion 250 may be located farther from the edge 130c of the rear surface 130b of the door 130 than the one end 250a.

The dyke 200 may include a protruding portion 260. The protruding portion 260 may protrude from the other end 250b of the base portion 250. The protruding portion 260 may protrude from the rear surface 130b of the door 130.

The refrigerator 100 may include a magnetic material (not shown) arranged along the edge of the storage compartments 121, 122, and the dyke 200 may include a magnetic material insertion groove 251 formed in the base portion 250. When the storage compartments 121, 122 are closed by the door 130, the magnetic material insertion groove 251 may be arranged at a position corresponding to the magnetic material (not shown). Through this configuration, when the door 130 is closed, the magnetic material (not shown) may be inserted into the magnetic material insertion groove 251, and the storage compartments 121, 122 may be completely sealed.

As described above, the dyke 200 may be a structure arranged along the edge 130c of the rear surface 130b of the door 130. Therefore, in a state where the storage compartments 121, 122 are closed by the door 130, one portion of the dyke 200 may be exposed to the outside of the storage compartments 121, 122, and another portion of the dyke 200 may be exposed to the storage compartments 121, 122.

For example, one end 250a of the base portion 250 may be exposed to the outside of the storage compartments 121, 122, and the other end 250b of the base portion 250 and the protruding portion 260 may be exposed to the storage compartments 121, 122. In this case, heat may be transferred from the outside of the storage compartments 121, 122 to the inside thereof through a path Q that sequentially passes through one end 250a of the base portion 250, the other end 250b of the base portion 250, and the protruding portion 260. This may reduce the cooling efficiency of the refrigerator 100.

According to an embodiment of the present disclosure, the dyke 200 may have low thermal conductivity. Accordingly, the amount of heat transferred from the outside to the inside of the storage compartments 121, 122 through the dyke 200 may be reduced. Hereinafter, a configuration for implementing low thermal conductivity of the dyke 200 will be described in greater detail.

The dyke 200 may include an envelope 210. A storage space 210a may be formed inside the envelope 210.

Gas may be stored inside the envelope 210. In other words, gas may be stored in the storage space 210a of the envelope 210.

For example, the gas stored in the storage space 210a of the envelope 210 may include a gas including a material having relatively low thermal conductivity. For example, the gas stored in the storage space 210a may include xenon gas.

The dyke 200 may include a plurality of partition layers 220. Each of the plurality of partition layers 220 may be arranged inside the envelope 210. The plurality of partition layers 220 may divide the storage space 210a into a plurality of spaces. In this case, there is no particular limitation on the number of the plurality of partition layers 220.

The plurality of partition layers 220 may be arranged along a path Q through which heat is transferred from the outside of the storage compartments 121, 122 toward the storage compartments 121, 122. In other words, the plurality of spaces divided by the plurality of partition layers 220 may be arranged along the path through which heat is transferred through the dyke 200.

For example, heat may be transferred from one end 250a of the base portion 250 to the other end 250b of the base portion 250, and then from the other end 250b of the base portion 250 to the protruding portion 260. The plurality of partition layers 220 may include a plurality of fourth partition layers 220a arranged along a third direction D3 in which the base portion 250 extends, and a plurality of fifth partition layers 220b arranged along a fourth direction D4, which is a direction in which the protruding portion 260 protrudes and intersects with the third direction D3. Through this configuration, the amount of heat transferred through the dyke 200 may be reduced.

The plurality of fourth partition layers 220a may divide the storage space 210a in the third direction D3. The plurality of fifth partition layers 220b may divide the storage space 210a in the fourth direction D4.

The plurality of fourth partition layers 220a may extend in the fourth direction D4, which intersects with the third direction D3, in order to divide the storage space 210a in the third direction D3. The plurality of fifth partition layers 220b may extend in the third direction D3, which intersects with the fourth direction D4, in order to divide the storage space 210a in the fourth direction D4.

The plurality of fourth partition layers 220a may be arranged spaced apart from each other in the third direction D3 in order to divide the storage space 210a into a plurality of spaces sequentially arranged along the third direction D3. The plurality of fifth partition layers 220b may be arranged spaced apart from each other in the fourth direction D4 in order to divide the storage space 210a into a plurality of spaces sequentially arranged along the fourth direction D4. In addition, each of the plurality of fourth partition layers 220a may be spaced apart from each of the plurality of fifth partition layers 220b.

The distance between two of the plurality of fourth partition layers 220a that are arranged adjacent to each other in the third direction D3 may be 10.4 mm or less. The distance between two of the plurality of fourth partition layers 220a that are arranged adjacent to each other in the third direction D3 may be 5 mm or more and 10.4 mm or less. A distance between two of the plurality of fourth partition layers 220a that are arranged adjacent to each other in the third direction D3 may be 10.4 mm.

The distance between two of the plurality of fifth partition layers 220b that are arranged adjacent to each other in the fourth direction D4 may be 10.4 mm or less. The distance between two of the plurality of fifth partition layers 220b that are arranged adjacent to each other in the fourth direction D4 may be 5 mm or more and 10.4 mm or less. A distance between two of the plurality of fifth partition layers 220b that are arranged adjacent to each other in the fourth direction D4 may be 10.4 mm.

Each of the plurality of partition layers 220 may include a base layer 221 and a coating layer 222 formed by coating aluminum on the base layer 221.

The base layer 221 may include a material through which gaseous substances cannot pass. For example, the base layer 221 may include a material arranged in the form of closed-cell foam.

The coating layer 222 may be configured to prevent and/or reduce heat transfer by thermal radiation. For example, the coating layer 222 may be configured to block heat transfer in the form of electromagnetic waves from high-temperature regions.

The coating layer 222 may be arranged on one surface of the base layer 221. For example, the base layer 221 may include a third surface 221a and a fourth surface 221b, which is opposite to the third surface 221a and is positioned farther than the third surface 221a with respect to the path Q through which heat is transferred, and the coating layer 222 may be arranged on the third surface 221a.

However, the coating layer 222 is not necessarily arranged only on the third surface 221a of the base layer 221. For example, the coating layer 222 may be arranged on both surfaces 221a and 221b of the base layer 221.

The coating layer 222 may cover most of one surface of the base layer 221. For example, the area of the coating layer 222 may be 90% or more of the area of the base layer 221.

The edge of the coating layer 222 may be arranged to be spaced apart from the envelope 210. That is, the coating layer 222 may not be in contact with the inner surface of the envelope 210.

The heat insulating materials 1, 2, 3, 4 according to an embodiment of the present disclosure have been described with reference to FIGS. 1, 2, 3, 4, 5, 6 and 7, and an embodiment in which the configuration of the heat insulating materials 1, 2, 3, 4 according to an embodiment of the present disclosure is applied to the dyke 200 of the refrigerator 100 has been described with reference to FIGS. 8 and 9. However, the present disclosure is not limited thereto. As described above, since the heat insulating materials 1, 2, 3, 4 according to various embodiments of the present disclosure can also be applied to components having complex structures, it is expected that the heat insulating materials 1, 2, 3, 4 according to an embodiment of the present disclosure can be applied to any component requiring insulation, regardless of its shape or size.

According to an embodiment, a heat insulating material 1, 2, 3, 4 includes an envelope 10 defining a storage space 11 and configured to store gas therein, a first partition layer 20a arranged inside the envelope 10, configured to divide the storage space 11 in one direction D1, and a second partition layer 20b arranged inside the envelope 10 and spaced apart from the first partition layer 20a in the one direction D1, the second partition layer configured to divide the storage space 11 into a plurality of spaces 11a, 11b, 11c together with the first partition layer 20a.

The gas stored in the storage space 11 may include xenon gas.

The widths W1, W2, W3 of each of the plurality of spaces 11a, 11b, 11c in the one direction D1 may be 10.4 mm or less.

The widths W1, W2, W3 of each of the plurality of spaces 11a, 11b, 11c in the one direction D1 may be 5 mm or more.

Each of the first partition layer 20a and the second partition layer 20b may include a base layer 21 and a coating layer 22 comprising aluminum disposed on the base layer 21.

The base layer 21 may include a material comprising closed-cell foam.

The base layer 21 may include polyethylene terephthalate (PET).

An edge of the coating layer 22 may be spaced apart from the envelope 10.

The area of the coating layer 22 may be 90% or more of the area of the base layer 21.

The one direction D1 may be a first direction D1, and the heat insulating material 4 may further include a third partition layer 20d arranged inside the envelope 10, configured to divide each of the plurality of spaces in a second direction D2 intersecting with the first direction D1.

According to an embodiment, a heat insulating material 1, 2, 3, 4 includes an envelope 10 defining a storage space 11 and configured to store gas therein, and a plurality of partition layers 20 arranged in the one direction D1 inside the envelope 10, configured to divide the storage space 11, wherein a distance between two partition layers 20 arranged adjacent to each other among the plurality of partition layers 20 in the one direction D1 is 10.4 mm or less.

The gas stored in the storage space 11 may include xenon gas.

The distance between two partition layers 20 arranged adjacent to each other among the plurality of partition layers 20 in the one direction D1 may be 5 mm or more.

Each of the plurality of partition layers 20 may include a base layer 21 and a coating layer 22 formed by coating aluminum on the base layer 21.

The base layer 21 may include a material provided in the form of closed-cell foam.

According to an embodiment, a refrigerator 100 includes a main body in which storage compartments 121, 122 are arranged, a door 130 configured to open and close the storage compartments 121, 122, a door basket 132 arranged on a rear surface 130b of the door 130, and a dyke 200 arranged along an edge 130c of the rear surface 130b of the door 130 and configured to support the door basket 132. The dyke 200 may include an envelope 210 configured to form a storage space 210a and to store gas therein, and a plurality of partition layers 220 arranged inside the envelope 210 and spaced apart from each other along a heat transfer path Q from outside the storage compartment 121, 122 toward the inside of the storage compartment 121, 122, to divide the storage space.

The dyke 200 may include a base portion 250 that is in contact with the rear surface 130b of the door 130 and extends in a direction parallel to the rear surface 130b of the door 130, having one end 250a and another end 250b positioned farther from the edge 130c of the rear surface 130b of the door 130 than the one end 250a, and a protruding portion 260 protruding from the other end 250b of the base portion 250, and the plurality of partition layers 220 may further include a plurality of first partition layers 220a arranged in a direction D3 in which the base portion 250 extends, and a plurality of second partition layers 220b arranged in a direction D4 in which the protruding portion 260 protrudes.

The distance between two first partition layers 220a arranged adjacent to each other among the plurality of first partition layers 220a in the direction D3 in which the base portion 250 extends and the distance between two second partition layers 220b arranged adjacent to each other among the plurality of second partition layers 220b in the direction D4 in which the protruding portion 260 protrudes may each be 5 mm or more and 10.4 mm or less.

Each of the plurality of partition layers 220 may include a base layer 221 and a coating layer 222 formed by coating aluminum on the base layer 221.

The base layer 221 may include a material provided in the form of closed-cell foam.

According to an embodiment of the present disclosure, the heat insulating material includes an envelope, a gas stored inside the envelope, and a plurality of partition layers arranged inside the envelope. That is, since most of the storage space inside the envelope is filled with gas, structural constraints on the shape of the heat insulating material may be relatively reduced. Therefore, the heat insulating material may be applicable to components having complex structures.

According to an embodiment of the present disclosure, the heat insulating material may include xenon gas stored inside the envelope. Xenon gas is an inert gas that has relatively low thermal conductivity. Accordingly, the heat insulating material may have relatively very low thermal conductivity.

According to an embodiment of the present disclosure, the heat insulating material may include a plurality of partition layers arranged inside the envelope. The plurality of partition layers may be spaced apart from each other at predetermined intervals along a direction in which heat is transferred. Through this configuration, natural convection inside the envelope may be prevented/reduced, and heat transfer caused by natural convection may be prevented/reduced.

According to an embodiment of the present disclosure, the dyke may include an envelope in which gas is stored and a plurality of partition layers arranged inside the envelope, spaced apart from each other along a path through which heat is transferred from outside the storage compartments toward the storage compartments. Accordingly, the amount of heat transferred from outside to inside the storage compartments through the dyke may be reduced.

The above has described and illustrated specific embodiments. However, the present disclosure is not limited to the above-described embodiments, and various modifications may be made by those of ordinary skill in the art without departing from the technical gist of the disclosure, including the following claims. It will also be understood than any of the embodiment(s) described herein may be used in conjunction with any other embodiment(s) described herein.