阅读说明：本技术 保鲜盒及其选用方法、冰箱 (Preservation box, selection method thereof and refrigerator ) 是由 陈佳弘 皮芳 张冰洁 于 2020-05-18 设计创作，主要内容包括：本发明公开了一种保鲜盒及其选用方法、冰箱,保鲜盒包括盒体,所述盒体包括开孔型泡沫塑料板,开孔型泡沫塑料板的厚度为100μm~500μm；保鲜盒的选用方法为：根据待储藏果蔬的比表面积确定待储藏果蔬的类别,根据待储藏果蔬的类别选用不同透湿率的开孔型泡沫塑料板；待储藏果蔬的类别包括：菌类、叶菜、果实类和混合类；开孔型泡沫塑料板根据透湿率的大小分为五类；开孔型泡沫塑料板的氧气透过率为200 mL/m2·24h到600 mL/m2·24h；开孔型泡沫塑料板的二氧化碳透过率为500 mL/m2·24h到1200 mL/m2·24h；冰箱包括保鲜盒。与现有技术比较,开孔型泡沫塑料使保鲜盒内部环境稳定,大大保证了果蔬的保鲜效果；同时其机械强度高、不易损坏。(The invention discloses a preservation box, a selection method thereof and a refrigerator, wherein the preservation box comprises a box body, the box body comprises an open-cell type foam plastic plate, and the thickness of the open-cell type foam plastic plate is 100-500 mu m; the selection method of the preservation box comprises the following steps: determining the category of the fruits and vegetables to be stored according to the specific surface area of the fruits and vegetables to be stored, and selecting open-cell foam plastic plates with different moisture permeability according to the category of the fruits and vegetables to be stored; the categories of fruits and vegetables to be stored include: fungi, leafy vegetables, fruits and mixtures; the open-cell foam plastic board is divided into five types according to the moisture permeability; the oxygen transmission rate of the open-cell foam plastic plate is 200mL/m 2.24h to 600mL/m 2.24h; the carbon dioxide transmission rate of the open-cell foam plastic plate is 500mL/m 2.24h to 1200mL/m 2.24h; the refrigerator comprises a preservation box. Compared with the prior art, the open-cell foam plastic ensures the internal environment of the fresh-keeping box to be stable, thereby greatly ensuring the fresh-keeping effect of fruits and vegetables; meanwhile, the mechanical strength is high and the damage is not easy to happen.)

1. The preservation box comprises a box body and is characterized in that the box body comprises an open-cell type foam plastic plate.

2. The crisper of claim 1, wherein the open-cell foam sheet has a thickness of 100 μm to 500 μm.

3. The crisper of claim 1, wherein the cassette body comprises a frame, the open cell foam sheet being removably mounted to the frame to form an outer wall of the cassette body.

4. A method for selecting a preservation box, which is characterized in that the preservation box is the preservation box according to any one of claims 1 to 2;

the selection method comprises the following steps: and (3) selecting open-cell foam plastic plates with different moisture permeability according to the strength of the evapotranspiration effect of the fruits and vegetables to be stored to prepare the preservation box.

5. The method for selecting a fresh keeping box according to claim 4, wherein the method for judging the strength of the transpiration of the fruits and vegetables to be stored comprises the following steps: determining the category of the fruits and vegetables to be stored according to the specific surface area of the fruits and vegetables to be stored, and selecting open-cell foam plastic plates with different moisture permeability according to the category of the fruits and vegetables to be stored.

6. The method as claimed in claim 5, wherein the categories of fruits and vegetables to be stored include:

fungi including mushroom, oyster mushroom, and needle mushroom;

leaf vegetables including spinach, pakchoi, water spinach, lettuce;

fruits including grapes, strawberries, apples, pears, cherries, green peppers, tomatoes;

a mixture comprising said fungi, leafy vegetables and fruits.

7. The method for selecting the preservation box according to claim 6, wherein the open-cell type foam plastic board is divided into the following components according to the moisture permeability: a first plastic foam board with a moisture permeability of 20g/m2 & 24h to 50g/m 2.24h; a second plastic foam board with the moisture permeability of 50g/m2 & 24h to 100g/m 2.24h; a third plastic foam board with the moisture permeability of 100g/m2 & 24h to 300g/m 2.24h; a fourth plastic foam board with the moisture permeability of 300g/m2 & 24h to 600g/m 2.24h; a fifth plastic foam board with the moisture permeability of 600g/m2 & 24h to 800g/m 2.24h;

when the fruits and vegetables to be stored are the fruits, the foam plastic plate is a first foam plastic plate or a second foam plastic plate; when the fruits and vegetables to be stored are the leaf vegetables, the foam plastic plate is a third foam plastic plate or a fourth foam plastic plate; when the fruits and vegetables to be stored are the fungi, the foam plastic plate is the fourth foam plastic plate or the fifth foam plastic plate; when the fruits and vegetables to be stored are the mixed type, the foam plastic plate is the second foam plastic plate or the third foam plastic plate or the fourth foam plastic plate.

8. The method for selecting a fresh food box according to claim 4, wherein the open-cell type foam plastic plate has an oxygen transmission rate of 200mL/m 2.24h to 600mL/m 2.24h.

9. The method as claimed in claim 4, wherein the open-cell foam board has a carbon dioxide transmittance of 500mL/m 2.24h to 1200mL/m 2.24h.

10. A refrigerator characterized in that it comprises a crisper according to any one of claims 1 to 3.

Technical Field

The invention relates to the field of preservation equipment, in particular to a preservation box, a selection method thereof and a refrigerator.

Background

With the improvement of living standard and purchasing power of people, higher requirements are put forward on the variety, quality and edible safety of fresh fruits and vegetables, and the natural quality and edible safety of the fruits and vegetables are required to be maintained to the maximum extent. The refrigerator is used as a terminal of a food refrigeration chain, the quality of the fresh-keeping performance of the refrigerator is directly related to people's life relatives, the fresh-keeping effect of a common household refrigerator is limited, the fresh-keeping time for fresh vegetables and fruits is short, and the fresh-keeping time is generally not more than one week; in order to improve the preservation effect, the controlled atmosphere preservation technology which is widely applied in the field is the controlled atmosphere preservation technology, and the controlled atmosphere preservation technology inhibits the respiration of fruits and vegetables, delays the metabolism process, enables the fruits and vegetables to be in a dormant state, prevents the fruits and vegetables from rotting and deteriorating and prolongs the storage period by controlling the parameters such as temperature, humidity, carbon dioxide, oxygen concentration, ethylene concentration and the like in the storage environment on the basis of the original refrigeration.

The preservation method of the preservation box of the refrigerator at present mainly comprises a continuous modified atmosphere (CA) method and a primary Modified Atmosphere (MA) method, wherein the continuous modified atmosphere (CA) method utilizes a manual equipment vacuum pump and an air separation membrane (PEI and PET are taken as main materials), oxygen in the preservation box is pumped out by taking pressure difference as a driving force, a storage environment rich in nitrogen and poor in oxygen is created, but the humidity in the fruit and vegetable box cannot be adjusted, a large amount of water vapor in the box can be pumped out when the system is started to pump out the oxygen, the humidity in the box can be reduced to accelerate water loss of the fruit and vegetable, and when the system is closed, the humidity in the box is increased sharply, a large amount of condensation can be generated, microorganisms can be bred, and the fruit; the primary air-conditioning Method (MA) mainly utilizes a high-molecular air-conditioning film (air separation film) mainly made of polyethylene, polyether sulfone, polytetrafluoroethylene or polyvinyl alcohol to adjust the gas components of the preservation box by combining the respiration and transpiration of fruits and vegetables, and the high-molecular air-conditioning film is a disposable plastic film which is low in thickness (10-30 mu m), low in mechanical strength, short in service life, easy to damage and difficult to wash, and can breed a large number of microorganisms after being applied to the fruit and vegetable boxes for a long time due to the high washing difficulty. Therefore, the important direction of research in the industry is to provide the fresh-keeping box and the refrigerator which have high mechanical strength, are not easy to damage and have strong stability and have the air conditioning function to effectively store the fruits and the vegetables.

Disclosure of Invention

In order to solve the problems, the invention provides a preservation box, a selection method thereof and a refrigerator.

The technical scheme provided by the invention is as follows: the preservation box comprises a box body, wherein the box body comprises an open-cell type foam plastic plate.

Further, the thickness of the open-cell foam plate is 100-500 μm.

Further, the case body includes a frame on which the open-cell type foam plastic sheet is detachably mounted to form an outer wall of the case body.

A method for selecting a preservation box is provided, wherein the preservation box is the preservation box; the selection method comprises the following steps: and (3) selecting open-cell foam plastic plates with different moisture permeability according to the strength of the evapotranspiration effect of the fruits and vegetables to be stored to prepare the preservation box.

Further, the method for judging the strength of the transpiration of the fruits and vegetables to be stored comprises the following steps: determining the category of the fruits and vegetables to be stored according to the specific surface area of the fruits and vegetables to be stored, and selecting open-cell foam plastic plates with different moisture permeability according to the category of the fruits and vegetables to be stored.

Further, the categories of the fruits and vegetables to be stored comprise: fungi including mushroom, oyster mushroom, and needle mushroom; leaf vegetables including spinach, pakchoi, water spinach, lettuce; fruits including grapes, strawberries, apples, pears, cherries, green peppers, tomatoes; a mixture comprising said fungi, leafy vegetables and fruits.

Further, the open-cell type foam plastic board is divided into the following components according to the moisture permeability: a first plastic foam board with a moisture permeability of 20g/m2 & 24h to 50g/m2 & 24 h; a second plastic foam board with a moisture permeability of 50g/m2 & 24h to 100g/m2 & 24 h; a third plastic foam board with the moisture permeability of 100g/m2 & 24h to 300g/m2 & 24 h; a fourth plastic foam board with the moisture permeability of 300g/m2 & 24h to 600g/m2 & 24 h; a fifth plastic foam board with the moisture permeability of 600g/m2 & 24h to 800g/m2 & 24 h; when the fruits and vegetables to be stored are the fruits, the foam plastic plate is a first foam plastic plate or a second foam plastic plate; when the fruits and vegetables to be stored are the leaf vegetables, the foam plastic plate is a third foam plastic plate or a fourth foam plastic plate; when the fruits and vegetables to be stored are the fungi, the foam plastic plate is the fourth foam plastic plate or the fifth foam plastic plate; when the fruits and vegetables to be stored are the mixed type, the foam plastic plate is the second foam plastic plate or the third foam plastic plate or the fourth foam plastic plate.

Preferably, the open-cell type foam sheet has an oxygen transmission rate of 200mL/m2 & 24h to 600mL/m2 & 24 h.

Preferably, the open-cell plastic foam sheet has a carbon dioxide transmission rate of 500mL/m2 & 24h to 1200mL/m2 & 24 h.

A refrigerator comprising any one of the crispers.

Compared with the prior art, the open-cell type foam plastic plate is not only used as a component of the box body of the preservation box, but also used as a modified atmosphere structure of the preservation box, because the cells in the open-cell type foam plastic are communicated with each other and are ventilated mutually, fluid can smoothly pass through the foam body, so that the open-cell type foam plastic plate has moisture permeability and air permeability, and still has good air permeability under a low-temperature and high-humidity environment, the open-cell type foam plastic can maintain the humidity in the fruit and vegetable box at 90-97%, the oxygen at 6-18% and the carbon dioxide at 1-5%, so that the internal environment of the preservation box is stable, and the preservation effect of the fruits and vegetables is greatly ensured; meanwhile, the strength and the hardness of the plastic are not much different from those of common plastics, so that the plastic is high in mechanical strength and not easy to damage; in addition, the preservation box made of open-cell foam can be washed, which is beneficial to the cleanness of the fruit and vegetable box and prevents the breeding of microorganisms.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.

FIG. 1 is a schematic diagram of the structure of the crisper in the embodiment of the present invention.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects to be solved by the present invention more clearly apparent, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The principles and construction of the present invention will be described in detail below with reference to the drawings and examples.

The invention provides a preservation box, as shown in figure 1, the preservation box comprises a box body 1, the box body 1 is of a closed structure formed by a plurality of plate bodies, the plate bodies comprise open-cell type foam plastic plates, the area of each open-cell type foam plastic plate can be adaptively designed according to the quantity of fruits and vegetables to be stored in the preservation box, when the quantity of the fruits and vegetables to be stored is large, the area of each foam plastic plate is large, when the quantity of the fruits and vegetables to be stored is small, the area of each foam plastic plate is correspondingly small, and in one embodiment, the side wall and the top plate of the preservation box are both made of the foam plastic plates.

The open-cell type foam plastic plate is not only used as a component of the box body of the preservation box, but also used as a modified atmosphere structure of the preservation box, because the cells in the open-cell type foam plastic are communicated with each other and are ventilated with each other, fluid can smoothly pass through the foam body, so that the open-cell type foam plastic plate has moisture permeability and air permeability, and still has good air permeability in a low-temperature and high-humidity environment, the open-cell type foam plastic can maintain the humidity in the fruit and vegetable box at 90-97%, the oxygen at 6-18% and the carbon dioxide at 1-5%, thereby the internal environment of the preservation box is stable, and the preservation effect of fruits and vegetables is greatly ensured; meanwhile, the strength and the hardness of the plastic are not much different from those of common plastics, so that the plastic is high in mechanical strength and not easy to damage; in addition, the preservation box made of open-cell foam can be washed, which is beneficial to the cleanness of the fruit and vegetable box and prevents the breeding of microorganisms.

Preferably, the thickness of the foam plastic plate is 100 to 500 μm in order to ensure the structural strength of the preservation box.

It should be noted that, the box body of the preservation box in this embodiment includes a frame, the frame is formed by splicing 12 support frame strips into a regular rectangular three-dimensional frame, the foamed plastic board is detachably installed on the frame to form the outer wall of the box body, wherein the outer wall of the box body may include a common plastic outer wall, or may include the open-cell foamed plastic provided in this application as the outer wall, and the area of the box body occupied by the open-cell foamed plastic board can be adjusted by people, so that when the volume of the box body cannot be changed, but the stored fruits and vegetables need higher humidity conditions, the humidity of the box body can be increased by increasing the area of the open-cell foamed plastic board, so that the applicability of the preservation box is greatly improved, and the preservation box can flexibly store various fruits and vegetables; certainly, under the condition that the proportion of the surface area of the preservation box occupied by the open-cell foam plastic is not changed, a user can meet the storage requirements of different fruits and vegetables by replacing the open-cell foam plastic boards with different moisture permeability, and the purpose of replacing the preservation box with different moisture permeability is achieved by replacing the open-cell foam plastic boards.

Preferably, the foam plastic board can be fixed on the frame through screws, and can also be fixed on the frame through a buckling structure; in this embodiment, through set up the recess of a relative setting on two frame strips about or on the frame is with one side, the one end opening of recess, the other end is for sealing for thereby the foamed plastic board can be followed the opening part of recess and inserted the fixed mounting of accomplishing on the frame. The above are only examples, and those skilled in the art can find countless ways to realize the detachable installation of the frame and the foam board in the existing solution, which should be included in the present invention.

Furthermore, the open-cell foam plastic adopted by the fruit and vegetable fresh-keeping box is mainly made of high polymer materials, such as one or more of polystyrene, polyurethane, polypropylene, polyethylene, polyvinyl chloride, polycarbonate, polylactic acid, polycaprolactone, polyperfluoroethylpropylene, polymethyl methacrylate, polyvinyl butyral and the like.

Further, the production process of the open-cell foam plastic is a physical foaming method, and specifically comprises a batch forming method and a continuous extrusion forming method.

A batch forming method: the main processing steps are divided into two steps, wherein the first step is to add inert gas (CO) under the conditions of room temperature and isostatic pressure (generally 5 MPa-7 MPa)₂Or N₂) Dissolving it in molten polymer under pressureOr a paste-like compound, in an inert gas, and after a certain period of time (generally over 24 hours), a supersaturated state is formed; taking out the polymer test piece from the isostatic pressure container, and quickly reducing the pressure or increasing the temperature; make CO₂Or N₂The solubility of the inert gas in the polymer decreases rapidly, thereby inducing great thermodynamic instability in the polymer containing saturated gas, and triggering the nucleation and growth of bubbles. The polymer test piece is taken out from the pressure container, and then is immediately placed in a hot glycerin bath for heating (the temperature is controlled to be near the glass transition temperature), the heating temperature and the heating time are controlled, and the product is subjected to liquid N₂After cooling, the desired cellular plastic is obtained.

Continuous extrusion molding method: the polymer granules or powder enter a plastic extruder from a hopper port, and CO₂Or N₂Injecting from the middle of the melting section of the plastic extruder to form larger initial bubbles, splitting the initial bubbles into a plurality of small bubbles after high-speed mixing and shearing of the screw, and accelerating the speed of gas diffusion to enter the polymer melt, thereby obtaining the open-cell foam plastic required by the invention.

The invention also provides a selection method of the preservation box, generally speaking, the preservation box is placed in a refrigerator to store fruits and vegetables at low temperature, the volume of the preservation box is 7.3L, and the proportion of the surface area of the preservation box occupied by the open-cell type foam plastic plate is constant. Under other conditions, such as the change of the volume of the preservation box and the surface area occupied by the preservation box, the open-cell type foam plastic plate with proper moisture permeability can still be selected by using the method.

The selection method of the preservation box comprises the following steps: the open-cell foam plastics with different moisture permeability are selected according to the evapotranspiration strength of the fruits and vegetables to be stored, because the fruits and vegetables with strong evapotranspiration have stronger water loss capability, the open-cell foam plastics with higher moisture permeability are selected, and vice versa.

Specifically, the selection method of the preservation box comprises the following steps:

fruit and vegetable classification: because the fruit vegetables that the refrigerator preservation box will be stored are of a great variety, consequently, can't obtain the power of the transpiration of every kind of fruit vegetables one by one, consequently, for the suitable trompil type foamed plastic of convenient selection moisture permeability, divide into the multiple classification with the fruit vegetables according to the power of the transpiration of fruit vegetables in this embodiment, and the power of the transpiration of fruit vegetables is relevant with the specific surface area of fruit vegetables, consequently the direct size according to the specific surface area of fruit vegetables of this embodiment classifies the fruit vegetables, and concrete classification is as follows: fungi, which mainly comprise fungi vegetables on the markets such as mushrooms, oyster mushrooms, needle mushrooms and the like; the leaf vegetables mainly comprise common leafy vegetables in the markets such as spinach, pakchoi, water spinach, lettuce and the like; fruits mainly including fruits and fruit-type vegetables such as grapes, strawberries, apples, pears, cherries, green peppers, tomatoes and the like; the mixed food mainly comprises the fungi, the leaf vegetables and the fruits which are mixed together.

According to the experiment, the following results are obtained: when various fruits and vegetables are in the same condition, the biological activity and storage condition of the fruits and vegetables in the preservation box are shown in the following table 1,

TABLE 1

(II) calculating the moisture permeability required by various fruits and vegetables: after the fruits and vegetables are classified, the moisture permeability of the open-cell foam plastic required by each type of fruits and vegetables is preliminarily calculated by performing experiments on various types of fruits and vegetables according to the existing classification, the volume of the preservation box and the area of the foam plastic are determined according to the actual use condition, then the moisture permeability of the foam plastic of the preservation box is calculated, in the embodiment, according to the use condition of the refrigerator, the volume of the preservation box is 7.3L, and the area proportion of the foam plastic is 200. The specific experimental tests are shown in table 2 below,

TABLE 2

The moisture permeability M of the open-cell foam can be calculated according to the above table and the formula M-R-S-V1/T, and the moisture permeability M of the open-cell foam can be calculated according to the formula M- ρ -V₂w/T can calculate the evapotranspiration water loss M of the fruits and vegetables, wherein M isThe water vapor permeability of the foam plastic (g/24h), R is the water vapor permeability of the foam plastic R (g/cm2 × 24h), S is the area ratio of the foam plastic of the fruit and vegetable box (cm2/L), V1 is the box volume (L), T is the storage time (h), m is the evapotranspiration water loss amount of the fruit and vegetable (g/24h), rho is the density of the fruit and vegetable (g/L), V2 is the volume of the fruit and vegetable (L), w is the average weight loss rate w (%) of the fruit and vegetable, and T is the storage time (T).

When M is larger than M, the humidity in the fruit and vegetable box can be reduced, and the water loss of the fruits and vegetables can be accelerated when the humidity is too low; when M is approximately equal to M, the humidity in the box is kept relatively stable, and the fruits and vegetables are easy to store; when M is less than M, the humidity in the box can be increased to more than 98%, condensation is generated in the box, and the fruits and vegetables are easy to rot due to excessive condensation.

Therefore, when M is M, the moisture permeability of the open-cell type foam plastic plate is the optimal moisture permeability, the water loss M of the fruits and vegetables can be calculated according to the above table, the value of the moisture permeability M of the open-cell type foam plastic can be obtained, and the formula M is R S V₁/T＝m＝ρ*V₂w/T to obtain R ═ (rho V)₂*w)/(S*V₁) And calculating the moisture permeability of the open-cell foam plastic corresponding to each type of fruits and vegetables.

As shown in the above table 2, the moisture permeability of the foam corresponding to fungi is 480.06-627.50 g/m2 x 24h, the moisture permeability of the foam of leafy vegetables is 85.56-288.75 g/m2 x 24h, and the moisture permeability of the foam of fruits is 35.75-87.00 g/m2 x 24 h.

And (III) because of individual differences between fruits and vegetables, the moisture permeability of the open-cell foam plastic corresponding to each type of fruits and vegetables can only be a range value, and in actual use, due to the limitation of manpower and material resources, the open-cell foam plastic with the moisture permeability cannot be independently designed and manufactured for a single variety.

The open-cell foam proposed in this example is divided into:

a first plastic foam board with a moisture permeability of 20g/m2 & 24h to 50g/m2 & 24 h;

a second plastic foam board with a moisture permeability of 50g/m2 & 24h to 100g/m2 & 24 h;

a third plastic foam board with the moisture permeability of 100g/m2 & 24h to 300g/m2 & 24 h;

a fourth plastic foam board with the moisture permeability of 300g/m2 & 24h to 600g/m2 & 24 h;

the fifth plastic foam board has a moisture permeability of 600g/m2 & 24h to 800g/m2 & 24 h.

The experimental detection is carried out according to the one-to-one matching of different types of fruits and vegetables and different types of open-cell foamed plastics, and the details are shown in the following comparison table 3 of the types of fruits and vegetables and the open-cell foamed plastics:

TABLE 3

From tables 2 and 4, according to the humidity in the box required by various fruits and vegetables and by combining the moisture permeability of the foam plastics required by various fruits and vegetables calculated in table 2, the foam plastic boards suitable for various fruits and vegetables can be screened out, and the screening results are as follows: the fruits are suitable for the first foam plastic plate and the second foam plastic plate, namely the moisture permeability of the foam plastic is 20-100 g/m2 x 24 h; the leaf vegetables are suitable for the third foam plastic plate and the fourth foam plastic plate, namely the moisture permeability of the foam plastic is 100-600 g/m2 for 24 h; the fungi are suitable for the fourth foam plastic plate and the fifth foam plastic plate, namely the foam plastic has the moisture permeability of 400-800 g/m2 x 24 h. The mixed fruits and vegetables are suitable for the second, third and fourth foam plastic plates, namely the moisture permeability of the foam plastic is 50-600 g/m2 for 24 h; the user can select the corresponding type of foam plastic boards according to the conclusion and the individual difference of the fruits and vegetables to be stored, so that the fruits and vegetables can be effectively and pertinently stored, the requirements of various fruits and vegetables on moisture permeability are met, and the selection process is convenient, rapid and practical.

(IV) determining the oxygen permeability and the carbon dioxide permeability of the foam plastic plate

For the content of oxygen and carbon dioxide in the control freshness preservation box, guarantee that the fruit vegetables do not take place respiration, open cell foam in this application needs the transmittance of oxygen and carbon dioxide to restrict, reachs following table 4 according to the experiment:

TABLE 4

As can be seen from the above table, when the open-cell foam has an oxygen transmission rate of 200 to 600mL/m2 & 24h and a carbon dioxide transmission rate of 500 to 1200mL/m2 & 24h, the oxygen content of the mixed fruits and vegetables is as low as 10 to 17%, and the carbon dioxide concentration is less than 5%, so that the fruits and vegetables do not produce anaerobic respiration, thereby being helpful for storing the fruits and vegetables.

The invention also provides a refrigerator which uses the preservation box provided by the invention.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.