Storage box

Abstract

To provide a storage box with high stain-resistant properties against liquid seasonings.SOLUTION: A storage box 1 has a surface coated with varnish, in which at least a portion of the varnished surface has a salt contact angle ratio calculated by the following formula (1) of 1.20 or more and a contact angle with water of 70° or larger. At least a portion of the varnished surface includes a portion with a height difference of 10 μm or more. The formula (1): Salt contact angle ratio=Contact angle with 18 mass% salt water CANaClaq / Contact angle with water CAwater.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a storage box. [Background technology]

[0002] Various types of storage boxes have been known in the past, including, for example, a roll storage box for storing a roll formed by rolling up a long object, a storage box for resin zipper bags such as Ziploc® bags, a storage box for resin bags such as plastic bags, a storage box for paper products such as tissues, and a storage box for foods such as sweets and chilled foods.Among these, a roll storage box is generally formed from a box-shaped main body portion that is covered on all four sides at the same height to store a roll, and a lid portion that closes the space in the main body portion, and the long object wound in the roll is pulled out from one long side of the main body portion and cut with a cutting blade formed on the end of the cover surface of the lid portion, allowing the long object to be used at a desired length.

[0003] For example, Patent Document 1 proposes such a wound body storage box, which includes a main body that forms a space for storing the wound body, and an openable and closable lid that closes the space in the main body, the main body having a bottom surface and a front surface that rises vertically from the bottom surface and is horizontal to the winding axis direction of the wound body, the front surface having a first region formed on the central side along the winding axis direction of the wound body and a second region formed on the end side, the second region having a surface height lower than that of the first region. Furthermore, for example, Patent Document 2 proposes a wound body storage box that includes a main body that forms a space for accommodating a wound body formed by winding a long object, and an openable and closable lid that closes the space in the main body, the main body having a bottom surface and a front surface that rises vertically from the bottom surface and is horizontal to the winding axis direction of the wound body, the lid having a cover surface that covers at least a portion of the front surface and a cutting blade formed on the lower edge of the cover surface, and when the lid is closing the main body, the lower end position of the cutting blade is within 25% of the height of the storage box from the lower end of the front surface. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2020-203697 [Patent Document 2] Japanese Patent Application Publication No. 2020-203699 Summary of the Invention [Problem to be solved by the invention]

[0005] As described above, known storage boxes include, for example, storage boxes for rolled products, storage boxes for plastic zipper bags, storage boxes for plastic bags, storage boxes for paper products, and storage boxes for food. However, these storage boxes may be used repeatedly, for example, in the kitchen. In such cases, the storage boxes are usually made of paper but are also required to have stain-resistant properties. In particular, liquid condiments such as soy sauce and sauces are often used in the kitchen, and if these liquid condiments come into contact with the storage box, their color and odor will remain. Therefore, there is a demand for storage boxes with higher stain-resistant properties for liquid condiments.

[0006] Therefore, an object of the present invention is to provide a storage box that has high stain-resistant properties against liquid seasonings. [Means for solving the problem]

[0007] As a result of extensive research, the present inventors have found that the above problems can be solved by using a storage box with a specific configuration, and have completed the present invention.

[0008] That is, the present invention relates to, for example, the following: [1] having a varnished surface, a storage box including, in at least a portion of the surface to which the varnish is applied, a portion in which the salt contact angle ratio calculated by the following formula (1) is 1.20 or more and the contact angle with water is 70° or more; Equation (1) Salt contact angle ratio = Contact angle CA with 18 mass% salt water NaClaq / Water contact angle CA water [2] The storage box according to [1], wherein at least a portion of the surface to which the varnish is applied includes a portion having a height difference of 10 μm or more. [Effects of the Invention]

[0009] According to the present invention, a storage box having high stain-resistant properties against liquid seasonings can be provided. [Brief explanation of the drawings]

[0010] [Figure 1] 1A is a perspective view showing an example of an opened state of a storage box according to the present invention, and FIG. 1B is a perspective view showing an unopened state of the storage box according to the present invention. [Figure 2] 2 is a diagram showing the storage box shown in FIG. 1 in an unfolded state. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, a detailed description will be given of an embodiment of the present invention (hereinafter abbreviated as "the present embodiment"). The following embodiment is an example for explaining the present invention, and the present invention is not limited to these. That is, the present invention can be implemented by modifying it as desired without departing from the gist of the present invention. In each drawing, components with the same reference numerals have the same or similar configurations. Furthermore, descriptions of configurations similar to conventional configurations will be omitted as appropriate.

[0012] The storage box of this embodiment has a surface coated with varnish, and at least a portion of the varnished surface includes a portion in which the salt contact angle ratio (hereinafter simply referred to as "salt contact angle ratio") calculated by the following formula (1) is 1.20 or more and the contact angle with water is 70° or more. Equation (1) Salt contact angle ratio = Contact angle CA with 18 mass% salt water NaClaq / Water contact angle CA water The storage box of this embodiment has such features, and thus has the effect of having high stain-resistant performance against liquid seasonings.

[0013] The mechanism by which the storage box of this embodiment exhibits such an effect is unclear, but the inventors speculate as follows: When the salt contact angle ratio and water contact angle calculated by Equation (1) are controlled within a specific range in a storage box, the box tends to repel liquid seasonings (salt-containing liquids) and become compatible with water to the extent that the portions to which the liquid seasoning has adhered can be easily removed with a water-absorbed nonwoven fabric. As a result, it is believed that the storage box of this embodiment exhibits the effect of having high stain-resistant performance against liquid seasonings.

[0014] In the storage box of this embodiment, the salt contact angle ratio is preferably 1.20 or more and 1.50 or less, and more preferably 1.25 or more and 1.50 or less.

[0015] Methods for controlling the salt contact angle ratio within the above range include, but are not limited to, methods such as adjusting the surface shape of the storage box and adjusting the composition of the applied varnish. Specifically, for example, if the surface shape of the storage box is uneven (e.g., a pseudo-embossed portion) and the surface area is large, the contact angle with water increases, but the contact angle with 18% by mass salt water tends to be even larger. Furthermore, for example, if the composition of the applied varnish contains amino groups and / or carbonyl groups, the contact angle with 18% by mass salt water remains almost unchanged, but the contact angle with water tends to decrease. The fact that the surface area of the storage box affects the contact angle can be confirmed, for example, from the theoretical formula for the contact angle below. Theoretical formula for contact angle: cosθ w =rcosθ e =r(γ SV -γ SL ) / γ LV θ w : Apparent contact angle of roughened surface θ e :Contact angle on a flat surface r: surface area ratio gamma SV : Surface tension of a solid gamma SL : Interfacial tension between solid and liquid gamma LV : Surface tension of the liquid Furthermore, the mechanism by which the contact angle with water decreases when the composition of the applied varnish contains amino groups and / or carbonyl groups is not clear, but the inventors speculate that it is due to the following: When the composition of the applied varnish contains amino groups and / or carbonyl groups, these amino groups and / or carbonyl groups interact with minerals (Ca) contained in water. 2+ , Mg 2+ ) and organic matter, the affinity between the surface of the storage box and water increases. As a result, the contact angle with water is thought to be small. On the other hand, minerals (Ca) contained in the salt water 2+ , Mg 2+ ) and organic matter are absorbed into the liquid by the inorganic salts in the salt water, making it difficult for the above-mentioned interactions to occur, and the affinity between the surface of the storage box and the salt water is not very high. As a result, it is thought that the contact angle will remain almost unchanged in the case of salt water, even if the varnish composition to be applied contains amino and / or carbonyl groups.

[0016] In the storage box of this embodiment, the contact angle with water is preferably 70° or more and 100° or less, and more preferably 73° or more and 95° or less.

[0017] Methods for controlling the water contact angle within the above range include, but are not limited to, methods such as adjusting the surface shape of the storage box and adjusting the composition of the applied varnish. Specifically, for example, if the surface shape of the storage box is uneven (e.g., a pseudo-embossed portion) and the surface area is large, the water contact angle tends to increase. Furthermore, for example, if the applied varnish contains hydrophilic functional groups such as amino groups or carbonyl groups, the water contact angle tends to decrease, whereas if it contains hydrophobic functional groups such as methyl groups or phenyl groups, the water contact angle tends to increase. The water contact angle can be controlled by adjusting the composition ratio of these groups.

[0018] In this embodiment, the contact angle with 18% by mass saline solution and the contact angle with water can be measured by the method described in the examples below.

[0019] Furthermore, the storage box of this embodiment tends to have excellent anti-fouling performance due to having a varnished surface. From this perspective, the proportion of the varnished surface of the storage box of this embodiment is preferably 80 area% or more, more preferably 85 area% or more, and even more preferably 90 area% or more. On the other hand, in terms of anti-fouling performance, the upper limit of the proportion of the varnished surface of the storage box of this embodiment is preferably 100 area%, but from the perspectives of storage box formation (for example, ensuring an area to apply adhesive) and cost, it is more preferably 99 area% or less, and even more preferably 98 area% or less.

[0020] Furthermore, the storage box of this embodiment preferably includes a portion with a height difference of 10 μm or more on at least a portion of the surface to which the varnish is applied. With this characteristic, the storage box of this embodiment tends to exhibit a more pronounced effect of having high stain-resistant performance against liquid seasonings. The upper limit of this height difference is not particularly limited, but is, for example, 50 μm or less. Specific examples of shapes with a height difference of 10 μm or more include, but are not limited to, embossing, debossing, and graining. Furthermore, such portions with a height difference of 10 μm or more are preferably formed in areas where liquid seasonings are likely to adhere, and specifically, for example, they are preferably formed on the lid 12, the outer surface of the front face 112, the back face 113, etc. of a storage box shaped as shown in Fig. 1, which will be described later. Forming portions with a height difference of 10 μm or more in such areas more significantly exhibits the effect of having high stain-resistant performance against liquid seasonings, and also exhibits the effect of making the storage box easier to hold.

[0021] Furthermore, in this embodiment, at least a portion of the surface to which the varnish is applied is preferably 20 to 100 area%, more preferably 35 to 100 area%, and even more preferably 50 to 100 area%, relative to 100 area% of the surface to which the varnish is applied.

[0022] Specific examples of the storage box of this embodiment are not particularly limited, but include, for example, a storage box for a roll of wrap film or the like (hereinafter also referred to as a "roll storage box"), a storage box for resin zipper bags such as Ziploc (registered trademark) bags, a storage box for resin bags such as plastic bags, a storage box for paper products such as tissues, and a storage box for food such as sweets and chilled foods. Among these, the storage box of this embodiment is preferably a roll storage box, a storage box for resin zipper bags, or a storage box for resin bags, more preferably a roll storage box or a storage box for resin zipper bags, and particularly preferably a roll storage box.

[0023] The shape of the storage box of this embodiment is not particularly limited, but may be, for example, a shape as shown in FIG. 1A and 1B are perspective views showing the overall configuration of a storage box 1 according to this embodiment, in which (A) shows the box in an open state and (B) shows the box in an unopened state. As shown in the figure, the storage box 1 includes a main body 11 that forms a space for accommodating a wound body (not shown), and an openable and closable lid 12 that closes the space of the main body 11.

[0024] [Outline of storage box configuration (Fig. 1)] The main body 11 comprises a bottom surface 111, a front surface 112 that rises vertically from the bottom surface 111 and is arranged horizontally to the winding axis direction of the wound body, a back surface 113 that also rises vertically from the bottom surface 111 and is arranged opposite the front surface 112, and a pair of front surfaces 112 (114a, 114b) that connect the bottom surface 111, the front surface 112, and the back surface 113 and support the front surface 112 and the back surface 113.

[0025] The lid portion 12 has an upper surface 121 that faces the bottom surface 111 when the main body portion 11 is closed, a cover surface 122 that covers at least a portion of the front surface 112 when the main body portion 11 is closed, and a pair of cover support surfaces 123 (123a, 123b) that support the upper surface 121 and the cover surface 122.

[0026] [Storage box assembly configuration (Figure 2)] Fig. 2 is a diagram showing the unfolded state of the storage box 1 shown in Fig. 1. The configuration of the main body 11 and the lid 12 of the storage box 1 will be described in detail using Fig. 2. In Fig. 2, the dashed lines indicate folds that are made when assembling the unfolded storage box 1.

[0027] As shown in FIG. 2, storage box 1 is assembled by cutting a single sheet of cardboard into each component, folding it, and joining it. The bottom 111 is folded 180° along the crease at the boundary between bottom 111 and back 113, and then folded along the crease at the boundary between cover 122 and top 121. The bottom 111 and adhesive strip 126 are then bonded together to form a flat, cylindrical intermediate body. Next, the cylindrical intermediate body is opened to form a roughly rectangular cross section. From the outside of support surfaces 114a and 114b, strips 112a and 112b, which are connecting parts between front 112 and support surface 114, are fixed to support surfaces 114a and 114b, respectively, by adhesive or the like. Furthermore, strips 113a and 113b, which are connecting parts between rear 113 and support surface 114, are fixed to support surfaces 114a and 114b and strips 112a and 112b of front 112, respectively, by adhesive or the like. This results in the assembled state of the main body 11 shown in FIG. 1(A).

[0028] Here, front surface 112 may be formed from a single sheet of paperboard, or may be formed from two or more sheets of paperboard by folding and pasting them together, etc. If the smoothness of the inner surface of front surface 112 is reduced by exposing the uncoated side of the paperboard, by providing unevenness with various varnishes such as pseudo-embossing varnish, or by embossing, it is possible to further prevent long objects from becoming entangled, and further, the effect of having high stain-resistant performance against liquid seasonings tends to be more pronounced. The assembly method is not limited to the above-mentioned sack-attaching method, and known methods such as a wrap-around method can also be used.

[0029] The lid portion 12 is formed by folding the cover surface 122 perpendicularly to the top surface 121 at the crease that defines the boundary, and pieces 122a and 122b, which are connecting parts between the cover surface 122 and the cover support surface 123, are fixed to the inside of the cover support surfaces 123a and 123b by adhesive or the like. Furthermore, the bottom surface 111b (adhesive piece) formed below the cover surface 122 is folded at the second perforation 125b (described later) that defines the boundary, and the bottom surface 111b (adhesive piece) is fixed to the bottom surface 111a from the outside by adhesive or the like. This results in the assembled state of the storage box 1 shown in FIG. 1(B).

[0030] [Lid configuration] Next, a description will be given of the lid part 12. As shown in Fig. 1(A), the lid part 12 has a cover surface 122 that covers at least a part of the front surface 112, and a cutting blade 124 is provided on the lower edge of this cover surface 122.

[0031] Specifically, as shown in Figures 1(B) and 2, the lid portion 12 has a fixed piece 125 connected to the main body portion 11, and an adhesive piece 126 is connected to this fixed piece 125, and this adhesive piece 126 is joined to the bottom surface 111 of the main body portion 11.

[0032] 2, one end of fixing piece 125 is connected to the lower end of cover surface 122, and the other end is connected to the side end of adhesive piece 126. Fixing piece 125, cover surface 122, and adhesive piece 126 are formed with first perforations 125a and second perforations 125b, which are made up of continuous holes shown in a line, and are configured to be peelable from the right end of the box in the direction of the arrow (this is called the "peeling direction"), as indicated by the arrow P in FIG. 1(B).

[0033] [Effects of the lid] According to the above-described configuration of the lid portion 12, the lower end position of the cutting blade 124 is set to within 33% of the height of the storage box 1 from the lower end of the front surface 112, which makes it possible to increase the length of the lid surface 122. This allows for a sufficient length of the long object after cutting, thereby reducing the amount of unwinding of the long object. Furthermore, a sufficient area of the lid surface 122 can be secured, allowing the long object to be securely held during cutting.

[0034] The above-described embodiments are intended to facilitate understanding of the present invention and are not intended to limit the present invention. The elements of the embodiments, as well as their arrangement, materials, conditions, shapes, sizes, etc., are not limited to those illustrated and can be modified as appropriate. Furthermore, configurations shown in different embodiments can be partially substituted or combined with each other. [Example]

[0035] The features of the present invention will be explained in more detail below with reference to examples and comparative examples, but the present invention is not limited thereto. That is, the materials, amounts used, ratios, processing details, processing procedures, etc. shown in the following examples can be appropriately changed without departing from the spirit of the present invention. Furthermore, the values of various production conditions and evaluation results in the following examples represent preferred upper or lower limits in the embodiments of the present invention, and preferred ranges may be defined by combining the above-mentioned upper or lower limits with the values of the following examples or values between the examples.

[0036] The measurement and evaluation methods used in the examples and comparative examples are as follows.

[0037] 1.Measuring methods for each physical property (a) Contact angle measurement The roll storage boxes obtained in the Examples and Comparative Examples described below were conditioned for 4 weeks at 40±2°C and 10±10% RH to reduce variations in storage period during distribution. Using a dynamic contact angle meter DMo-501 manufactured by Kyowa Interface Science Co., Ltd., 2 μL of tap water (Suzuka City water) with a hardness of 50±10 mg / L was dropped onto the varnish coating layer of the conditioned roll storage box. After 2 seconds, the contact angle was measured at 10 random locations on the varnish coating layer using the θ / 2 method, which is an automatic measurement method, with analysis software (FAMAS). The arithmetic mean value of the contact angles at the 10 measured locations was calculated as the contact angle measurement value CA. water The contact angle measurement value CA for 2 μL of 18 mass% saline was also measured in the same manner.NaClaq The 18% by mass saline solution was prepared by mixing 18 g of sodium chloride (Tokyo Chemical Industry Co., Ltd., purity 99.5% or higher) with 82 g of tap water. To eliminate the effect of static electricity on the droplets, the varnish layer was neutralized using a Mascot static eliminator manufactured by Riken Seiko Co., Ltd. before measurement. Measurements were performed in a temperature-controlled room at 23 ± 2°C and 50 ± 10% RH. The droplets were prepared using a manufacturer-supplied heat-resistant glass syringe and a stainless steel needle with an inner diameter of 0.47 mm. The varnish layer must be selected based on the location where the droplets will be formed completely on the varnish layer. For example, if the varnish layer has a dotted pattern, such as when 2 μm droplets do not form completely on the varnish layer, the amount of droplets applied can be reduced to reduce the droplet size. However, this does not apply to unevenness on the varnish surface; as long as the droplets are formed on the varnish layer, this does not apply to unevenness on the varnish surface. Measured CA water and CA NaClaq The salt contact angle ratio was calculated using the following formula (1). Equation (1) Salt contact angle ratio = Contact angle CA with 18 mass% salt water NaClaq / Water contact angle CA water

[0038] (b) Check the height difference of the varnish coating layer For the roll storage boxes obtained in the Examples and Comparative Examples described below, the height difference of the varnish coating layer was measured using a Keyence VK-X1000 laser microscope. A sample piece was cut from the varnish coating layer and placed on the stage. A 20x objective lens was selected, laser confocal mode was selected, the measurement size was set to "standard," the measurement quality was set to "high precision," and the pitch was set to "0.75 μm." The bonding measurement was performed, and a 3.6 mm x 6.4 mm observation image was created. The tilt was corrected using image processing. Five cross-sectional views were then randomly drawn along the longitudinal direction. If there was at least one location in the view where the difference between the top and bottom values was 10 μm or more, the height difference was determined to be 10 μm or more.

[0039] 2. Evaluation method (seasoning wipe-off evaluation) [Anti-fouling performance against liquid seasonings (soy sauce test)] On the surface of the rolled body storage box obtained in the Examples and Comparative Examples, 500 μL of soy sauce (manufactured by Kikkoman Corporation, product name: Always Fresh Freshly Squeezed Raw Soy Sauce) was measured using a micropipette (manufactured by AS ONE Corporation, Pipette Guy PG2 series), and two drops were dripped onto the varnish coating layer and left to stand for 10 minutes. Then, tap water (Suzuka City Water) with a hardness of 50±10 mg / L measured with a micropipette was dripped onto the soy sauce to create part A, and part B, where five drops were dripped. After 10 seconds, a tissue (Crecia EF Hand Towel Soft Type 200) folded in four was placed on top and left to stand until all the liquid had penetrated the tissue. The surface of the rolled body storage box was then observed and evaluated according to the following criteria. [Evaluation criteria] If colored areas remain in both parts A and B: "X". If the colored area remains in part A and disappears in part B: "Good". If the colored areas of both parts A and B have disappeared: "◎".

[0040] [Manufacturing Examples 1-2] Each component was mixed in the blending ratio (parts by mass) shown in Table 1 to produce a UV-curable varnish.

[0041] [Examples 1 and 2, Comparative Example 1] Basis weight 550g / m 2 The UV-curable varnish produced in each manufacturing example as shown in Table 2 was applied to a storage mount approximately 310 mm wide in the longitudinal direction, as shown in Figure 2, and cured by irradiating it with two 175 W / cm UV lamps to produce a varnish coating layer. The storage mount was then sharpened and assembled using a sack machine to produce a roll storage box with a varnish coating layer. The physical properties of the resulting roll storage box were measured and evaluated using the methods described above. Table 2 also shows the results of the contact angle measurement, salt contact angle ratio, and seasoning wiping evaluation for the roll storage box having a varnish coating layer. In Example 1, a release varnish (UV Release OP Varnish UP-2 manufactured by T&K TOKA) was applied as a base for the varnish coating layer, thereby producing a varnish coating layer with a height difference of 10 μm or more.

[0042] Comparative Example 2 A wound body storage box was produced in the same manner as in Example 1, except that no varnish coating layer was formed. The obtained wound body storage box was measured and evaluated for various physical properties using the methods described above. The results are shown in Table 2.

[0043] [Comparative Examples 3 to 4] In Comparative Examples 3 and 4, the properties of rolled body storage boxes commercially available in Japan were measured and evaluated using the above-mentioned methods, using a rolled body storage box with a varnish coating layer with a height difference of 10 μm or more and a rolled body storage box with a varnish coating layer without a height difference of 10 μm or more. The results are shown in Table 2.

[0044] [Table 1]

[0045] [Table 2]

[0046] As is clear from Table 2, the storage box with the specific configuration of the present invention is less likely to have liquid seasonings adhere to the varnish coating layer, and even if they do adhere, they can be easily removed, demonstrating higher anti-fouling properties against liquid seasonings. [Explanation of symbols]

[0047] 1...storage box, 11...main unit, 111,111a,111b...bottom, 112...front, 112a,112b...piece, 112c,112d...recess, 113...back, 11 3a,113b...piece, 114,114a,114b...support surface, 12...lid part, 121...top surface, 122...cover surface, 122a,122b...piece, 123,123a,12 3b...lid support surface, 124...cutting blade, 125...fixing piece, 125a...first perforation, 125b...second perforation, 125c, 125d...holes, 125ca, 125da...outer holes, 125cb, 125cc, 125db...inner holes, 126...adhesive piece, A1...first region, A2...second region, A3...third region, P...peel-off direction, X...winding axis

Claims

1. having a varnished surface, a storage box including, in at least a portion of the surface to which the varnish is applied, a portion in which the salt contact angle ratio calculated by the following formula (1) is 1.20 or more and the contact angle with water is 70° or more; Equation (1) Salt contact angle ratio = contact angle CA with 18 mass% saline solution NaClaq / Contact angle with water CA water

2. 2. The storage box according to claim 1, wherein at least a portion of the surface to which the varnish is applied includes a portion having a height difference of 10 μm or more.

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