Packing method
The packaging method secures items of varying sizes and shapes using sheets or containers with protrusions or convex portions that maintain a crushed shape, addressing inefficiencies and damage in traditional packaging methods.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- KOBAYASHI & CO LTD
- Filing Date
- 2025-12-08
- Publication Date
- 2026-07-02
AI Technical Summary
Existing packaging methods for diverse goods of varying sizes and shapes are inefficient and prone to damage during transport due to the need for custom-made cushioning materials and the inability of flexible materials to stabilize items within containers.
A packaging method using sheets or containers with scattered protrusions or convex portions that maintain a crushed shape to secure and stabilize items of different sizes and shapes, utilizing a resin composition with biomass materials for ease of crushing and shape retention.
Enables continuous and efficient packaging of diverse items by fixing them in place, preventing lateral movement and damage during transport, while allowing for uniform container sizes and reducing material waste.
Smart Images

Figure JP2025042636_02072026_PF_FP_ABST
Abstract
Description
Packing method
[0001] This technology relates to packaging methods.
[0002] When packing goods for transport or storage, it is common practice to place the goods inside containers such as cardboard boxes. In particular, when packing fragile electronic components or easily damaged goods, the goods are protected from damage caused by impacts and lateral movement during transport by covering them with cushioning material before placing them inside the container.
[0003] Typical cushioning materials used to protect articles include those made of so-called expanded polystyrene or three-dimensionally molded cardboard with recesses formed in them, into which at least a portion of the article is fitted to secure it (see Patent Documents 1 and 2). Flexible air packing (air caps) that enclose articles are also used as cushioning materials (see Patent Document 3).
[0004] In recent years, with the diversification of lifestyles, mail order has become commonplace, and retailers are now providing individual delivery of goods as a customer service. As a result, a wide variety of products are delivered directly to consumers, and along with the diversity of products, the size, shape, quantity, and strength of the delivered goods also vary.
[0005] On the other hand, since it is advantageous in terms of material and delivery costs to use containers of a uniform size when shipping goods, it is common practice not to prepare containers of various sizes for various products, but to put products into containers of a single or limited number of sizes, fill the gaps with cushioning material, and ship them. Japanese Patent Publication No. 2005-212815 Japanese Patent Publication No. 2005-313942 Japanese Patent Publication No. Hei 05-004665
[0006] However, among cushioning materials, expanded polystyrene and cardboard are formed to match the external shape of the container they will be placed in, and have recesses that correspond to the shape of the items. While such cushioning materials are very suitable for placing items of a specific shape and size in a specific container, they cannot be used for items of various shapes or sizes. In other words, cushioning materials must be custom-made for each item to be packaged.
[0007] On the other hand, because bubble wrap is a flexible sheet, it can enclose items of various shapes and sizes. However, in this case, when an item is wrapped in bubble wrap, its outer shape does not correspond to the internal shape of the container, causing rattling inside the container and increasing the likelihood of damage due to lateral movement during transport. Therefore, although bubble wrap provides cushioning, the risk of damage due to rattling inside the container is not eliminated. To prevent rattling of items inside the container, it is necessary to perform cumbersome tasks such as inserting other cushioning material as packing inside the container, which greatly reduces packaging efficiency.
[0008] Typically, goods are packaged in a way that involves continuously placing multiple items into a container and covering them with cushioning material during the packaging process. However, when goods are packaged in the same packaging process, if the size and shape of each item differs, it becomes necessary to prepare separate boxes and cushioning materials for each item, which is inefficient and uneconomical.
[0009] The present invention aims to provide a packaging method that can continuously and efficiently package articles of different sizes and shapes during the packaging process, and that can prevent damage caused by lateral shaking during transport.
[0010] The present invention provides a packaging method in which an object to be packaged is pressed against the protrusions of a sheet with scattered protrusions, and when the protrusions are crushed, the protrusions maintain the crushed shape caused by the object to be packaged, and the object to be packaged is fixed by the crushed shape of the protrusions and / or the protrusions that maintain their original, uncrushed shape. The sheet with scattered protrusions may be formed from a resin composition containing a biomass material and a thermoplastic resin. In the packaging method, the end face of the object to be packaged opposite to the sheet side may be covered with a film, and the object to be packaged may be pressed against the protrusions with the film. In the packaging method, the object to be packaged may be sandwiched between the sheet with scattered protrusions from above and below. In the packaging method, the object to be packaged may be sandwiched between the sheet with scattered protrusions from above and below. In the packaging method, the object to be packaged may be sandwiched between the sheet with scattered protrusions from above and below and from all sides. In the packaging method, the sheet with scattered protrusions may be wrapped around the object to be packaged. Furthermore, the present invention also provides a packaging method for packaging an object to be packaged using a sheet with scattered protrusions, wherein the protrusions of the sheet are pre-flattened to match the shape of the object to be packaged, and the object to be packaged is placed and fixed in the flattened areas, so that the object to be packaged can be fixed by the flattened shape of the protrusions and / or the protrusions that maintain their original, unflattened shape. Furthermore, the present invention also provides a packaging method for packaging an object to be packaged using a sheet with scattered protrusions, wherein all the protrusions of the sheet are pre-flattened, the object to be packaged is placed on the flattened protrusions, and then the back side of the flattened protrusions is pressed to match the shape of the object to be packaged, thereby restoring the shape of the protrusions and fixing the object to be packaged with the flattened shape of the protrusions and / or the protrusions that maintain their original, unflattened shape.Furthermore, the present invention also provides a packaging method for arranging an object to be packaged in a packaging container having a bottom portion and a container portion, which is formed by molding from a single sheet, wherein upward-facing protrusions are formed on the bottom portion, and the object to be packaged is placed in the packaging container so as to be pressed down on the protrusions from above, and when the protrusions are crushed, the protrusions maintain the shape crushed by the object to be packaged, and the object to be packaged is fixed in place by the crushed shape of the protrusions and / or the protrusions that maintain their original, uncrushed shape. The packaging container is provided with a lid portion that closes the opening on the upper end surface of the container portion, and when the opening is closed, the object to be packaged can be pressed down on the protrusions by the lid portion. The lid portion is formed with convex portions extending toward the bottom portion, and when the opening is closed, the lid portion presses the object to be packaged against the convex portions formed on the bottom portion and the convex portions formed on the lid portion, and when the convex portions are crushed, the convex portions maintain the shape crushed by the object to be packaged, and the object to be packaged can be fixed by the crushed shape of the convex portions and / or the convex portions that maintain their original, uncrushed shape. The present invention also provides a packaging method for accommodating an object to be packaged in a packaging container obtained by molding from a plurality of sheets, comprising a bottom portion, a container portion, and a lid portion that closes the opening on the upper end surface of the container portion, wherein the bottom portion is formed with convex portions extending toward the top portion, and the object to be packaged is placed in the packaging container so as to be pressed from above against the convex portions, and when the convex portions are crushed, the convex portions maintain the shape crushed by the object to be packaged, and the object to be packaged can be fixed by the crushed shape of the convex portions and / or the convex portions that maintain their original, uncrushed shape. The lid is formed with convex portions that extend toward the bottom surface, and when the opening is closed, the lid presses the object to be packaged against the convex portions formed on the bottom surface and the convex portions formed on the lid, and when the convex portions are crushed, the convex portions maintain the shape crushed by the object to be packaged, and the object to be packaged can be fixed in place by the crushed shape of the convex portions and / or the convex portions that maintain their original, uncrushed shape.In the above packaging method, the object to be packaged may be secured manually. In the above packaging method, the object to be packaged may be secured automatically.
[0011] The present invention provides a packaging method that enables the continuous and efficient packaging of articles of different sizes and shapes during the packaging process.
[0012] This is a perspective view showing an example of a sheet with scattered protrusions used in the packaging method of this embodiment. This is a plan view of a sheet 10 with scattered protrusions used in the packaging method of this embodiment. This is a cross-sectional view taken along line A-A in Figure 2. This is a perspective view of a sheet 40 with scattered protrusions used in the packaging method of this embodiment. This is a perspective view of a sheet 50 with scattered protrusions used in the packaging method of this embodiment. This is a plan view of a sheet 50 with scattered protrusions used in the packaging method of this embodiment. This is a cross-sectional view taken along line A-A in Figure 6. This is a perspective view of a sheet 50. This is a plan view showing the appearance of the protrusions 51 after the object to be packaged P is pressed against the protrusions 51 of the sheet and the protrusions 51 are crushed. This is a perspective view showing the appearance of the protrusions 51 after the object to be packaged P is pressed against the protrusions 51 of the sheet and the protrusions 51 are crushed, and then the object to be packaged P is removed. This is a perspective view of a sheet 60 with scattered protrusions used in the packaging method of this embodiment. This is a plan view of the sheet 60 with scattered protrusions used in the packaging method of this embodiment. This is a cross-sectional view taken along line A-A in Figure 13. This is a two-layer sheet consisting of layer A and layer B used in the packaging method of this embodiment. This is a three-layer sheet consisting of layer A, layer B, and layer A used in the packaging method of this embodiment. This is a three-layer sheet consisting of layer A, layer B, and layer C used in the packaging method of this embodiment. This is a perspective view showing the object to be packaged P pressed against the sheet 60. This is a cross-sectional view taken along line A-A in Figure 18. This is a schematic diagram showing how the object to be packaged P is sandwiched between the sheet 60 with scattered protrusions on the top and bottom. This is a schematic diagram showing how two of the four sides of the object to be packaged P are sandwiched between the sheet 60 with scattered protrusions from the left and right directions. This diagram schematically shows how a sheet 60 with scattered protrusions is pressed against the object to be packaged P from above and below, and how a pair of two of the four sides of the object to be packaged P are pressed against the sheet 60 with scattered protrusions from the left and right. This is a photograph taken from the back of the surface of the sheet 50 that contacts the object, showing the object to be packaged pressed against the sheet 50 and the completely flattened protrusions 51A. This is a photograph taken from the back of the flattened protrusions 51A after the flattened parts have been pressed with a finger to restore their shape. This is a photograph taken of the protrusions 51A after their shape has been restored by a finger.This is a schematic cross-sectional view showing the upper surface of an object to be packaged covered by a film. This is a schematic cross-sectional view showing a gap between the upper surface of the object to be packaged and the film. This is a schematic cross-sectional view showing a packaging container formed from a single sheet, with a portion dotted with protrusions serving as the bottom and a portion without protrusions serving as the container. This is a schematic cross-sectional view showing a packaging container formed from a single sheet, with a portion dotted with protrusions serving as the bottom, a portion without protrusions serving as the container, and a lid portion that opens and closes the opening of the container portion. This is a schematic cross-sectional view showing a packaging container formed from a single sheet, comprising a bottom portion with upward-pointing protrusions, a container portion, and a lid portion that closes the opening at the upper surface of the container portion.
[0013] Preferred embodiments of the present invention will be described below. The embodiments described below represent typical embodiments of the present invention, and the scope of the present invention is not limited to these embodiments.
[0014] The present invention will be described in the following order: 1. First Embodiment (An Example of Packaging Method) 2. Second Embodiment (Another Example of Packaging Method) 3. Third Embodiment (Another Example of Packaging Method) 4. Fourth Embodiment (Another Example of Packaging Method)
[0015] 1. First Embodiment (An Example of Packaging Method)
[0016] The packaging method of this embodiment will now be described with reference to the drawings. In this specification, the "direction perpendicular to the object to be packaged, when the surface on which the object to be packaged is placed faces upward," is referred to as the "thickness direction," and the "any direction in a plane perpendicular to the thickness direction" is referred to as the "plane direction." Furthermore, the "view of the object to be packaged, when the surface on which the object to be packaged is placed faces upward, from above in the vertical direction in the thickness direction" is referred to as the "planar view."
[0017] In the packaging method of this embodiment, first, a sheet with protruding portions scattered thereon and a packaging container are prepared. As the sheet with protruding portions scattered thereon, for example, a sheet with a plurality of protruding portions scattered thereon is used. Next, the sheet with protruding portions scattered thereon is placed in the packaging container. The object to be packaged is pressed against the protruding portions of the sheet placed in the packaging container, crushing the protruding portions. The crushed protruding portions maintain the crushed shape, while the protruding portions in the surrounding portions where the object to be packaged is not pressed remain in the original uncrushed shape. The object to be packaged is gripped and fixed by the protruding portions that maintain the crushed shape and the protruding portions that maintain the original uncrushed shape. As the packaging container, for example, a container formed from a container portion that houses the object to be packaged inside and a lid portion is used. Hereinafter, the sheet with protruding portions scattered thereon and the packaging container used in the packaging method of this embodiment will be described.
[0018] [Sheet with Protruding Portions Scattered Thereon]
[0019] FIG. 1 is a perspective view of a sheet 10 with protruding portions scattered thereon used in the packaging method according to this embodiment. FIG. 2 is a plan view of the sheet 10 with protruding portions scattered thereon used in the packaging method according to this embodiment. FIG. 3 is a cross-sectional view taken along line A-A in FIG. 2. As shown in FIG. 1, a plurality of protruding portions 1 are scattered on the sheet 10. As shown in FIG. 2, the cross-sectional shape (outer peripheral shape) of the protruding portion 1 is circular. As shown in FIG. 3, the protruding portion 1 is a single-stage protruding portion having a single-stage structure. From the viewpoint of preventing the lateral sway of the object to be packaged during packaging, the height H1 of the protruding portion 1 preferably has a ratio (height H1 of the protruding portion 1 / height of the object) of 0.2 or more, more preferably 0.33 or more, and even more preferably 1 or more with respect to the height of the object. Also, the height H1 of the protruding portion 1 may preferably be 0.1 cm to 5 cm, more preferably 0.2 cm to 4 cm, and even more preferably 0.3 cm to 3 cm. Further, the height H1 of the protruding portion 1 preferably has a ratio (height H1 of the protruding portion 1 / diameter of the cross-sectional shape of the protruding portion 1) of 0.33 or more, more preferably 0.5 or more, and even more preferably 1 or more with respect to the diameter of the cross-sectional shape of the protruding portion 1.
[0020] FIG. 4 is a perspective view of a sheet 40 with protruding portions scattered thereon used in the packaging method according to this embodiment. In the sheet 40, the height H of the protruding portion 4151 , 51 ,
[0022] , is higher than the height H1 of the convex portion 1 of the sheet 10. The height H of the convex portion 41 41 is the ratio of the convex portion to the diameter of the cross-sectional shape of the convex portion (convex portion 41 height H 41 / diameter of the cross-sectional shape of the convex portion 41) may preferably be 2 or more, more preferably 3 or more, and even more preferably 5 or more.
[0021] Fig. 5 is a perspective view of the sheet 50 with convex portions dotted thereon used in the packaging method according to the present embodiment. Fig. 6 is a plan view of the sheet 50 with convex portions dotted thereon used in the packaging method according to the present embodiment. Fig. 7 is a cross-sectional view taken along the line A-A in Fig. 6. As shown in Fig. 5, a plurality of convex portions 51 are dotted on the sheet 50. As shown in Fig. 6, in the convex portion 51, the cross-sectional shapes (outer peripheral shapes) of the first-stage and second-stage convex portions are circular. As shown in Fig. 7, the convex portion 51 is a multi-stage convex portion having a two-stage structure of a first stage 51f and a second stage 51s. From the viewpoint of making the convex portion 51 easily collapsible when the object to be packaged is pressed against the convex portion 51, the convex portion is preferably a multi-stage convex portion having a multi-stage structure of two or more stages. The convex portion may preferably be two or more stages, more preferably three or more stages, and even more preferably four or more stages. When the object to be packaged is pressed against such a multi-stage convex portion, the convex portion of the stage in contact with the object to be packaged is easily crushed, and the shape crushed by the object to be packaged is maintained. From the viewpoint of preventing lateral sway of the object to be packaged during packaging, the height H of the convex portion 51 51 is the ratio of the height of the convex portion to the height of the object (height H of the convex portion 51 51 / height of the object) may preferably be 0.2 or more, more preferably 0.33 or more, and even more preferably 1 or more. Further, the height H of the convex portion 51 51 is preferably 0.1 cm to 5 cm, more preferably 0.2 cm to 4 cm, and even more preferably 0.3 cm to 3 cm. Further, the height H of the convex portion 51 51 is the ratio of the height of the convex portion 51 to the diameter of the cross-sectional shape of the first stage 51f of the convex portion 51 (height H of the convex portion 51 51 / diameter of the cross-sectional shape of the first stage 51f of the convex portion 51) may preferably be 0.33 or more, more preferably 0.5 or more, and even more preferably 1 or more.
[0022] Also, from the perspective of making the convex portion 51 easily crushed when the object to be packed is pressed against the convex portion 51, the height H of the first stage 51f of the convex portion 51 51f is the height H of the convex portion 51 51 The ratio to H (the height H of the first stage of the convex portion 51 51f / H 51 ) may preferably be 0.066 or more, more preferably 0.2 or more, and even more preferably 0.5 or more. Also, the height H of the first stage 51f of the convex portion 51 51f may preferably be 0.1 cm to 1.4 cm, more preferably 0.2 cm to 1.3 cm, and even more preferably 0.3 cm to 1.2 cm. Also, the height H of the first stage 51f of the convex portion 51 51f is the ratio of the height H of the first stage 51f of the convex portion 51 to the diameter of the cross-sectional shape of the first stage 51f of the convex portion 51 (the height H of the first stage of the convex portion 51 51f / the diameter of the cross-sectional shape of the first stage 51f of the convex portion 51) may preferably be 0.066 or more, more preferably 0.133 or more, and even more preferably 0.5 or more. Also, from the perspective of making the convex portion 51 easily crushed when the object to be packed is pressed against the convex portion 51, the height H of the second stage 51s of the convex portion 51 51s is the height H of the convex portion 51 51 The ratio to H (the height H of the second stage of the convex portion 51 51s / H 51 ) may preferably be 0.066 or more, more preferably 0.2 or more, and even more preferably 0.5 or more. Also, the height H of the second stage 51s of the convex portion 51 51s may preferably be 0.1 cm to 1.4 cm, more preferably 0.2 cm to 1.3 cm, and even more preferably 0.3 cm to 1.2 cm. Also, the height H of the second stage 51s of the convex portion 51 51s [[ID=2,6]] is the ratio of the height H of the second stage 51s of the convex portion 51 to the diameter of the cross-sectional shape of the first stage 51f of the convex portion 51 (the height H of the second stage of the convex portion 51 51s / the diameter of the cross-sectional shape of the first stage 51f of the convex portion 51) may preferably be 0.066 or more, more preferably 0.133 or more, and even more preferably 0.5 or more.
[0023] The sheet 50 with scattered protrusions used in the packaging method according to this embodiment maintains a shape in which the entire protrusion 51 is crushed when the object to be packaged is pressed against the protrusions 51. In addition, when the protrusions 51 are crushed, the protrusions 51 maintain a shape in which only a portion of the protrusions 51 are crushed by the object to be packaged. The sheet with scattered protrusions used in the packaging method according to this embodiment does not easily return to its original shape after being crushed, and therefore it is possible to sandwich and fix the object to be packaged in its crushed shape. Figure 8 is a perspective view of the sheet 50. Figure 9 is a plan view showing the object to be packaged P pressed against the protrusions 51 of the sheet and the protrusions 51 being crushed. Figure 10 is a perspective view showing the object to be packaged P pressed against the protrusions 51 of the sheet and the protrusions 51 being crushed. Figure 11 is a perspective photograph showing the state of the protrusion 51 after the object to be packaged P is pressed against the protrusion 51 of the sheet, the protrusion 51 is crushed, and then the object to be packaged P is removed. In Figures 9, 10, and 11, protrusion 51A maintains the shape in which the entire protrusion 51 is crushed. Protrusion 51B maintains the shape in which a part of the protrusion 51 is crushed. Protrusion 51C maintains its original, uncrushed shape. As shown in Figures 9, 10, and 11, the object P is fixed by the protrusions 51A, 51B, and 51C. More specifically, as shown in Figure 11, the object to be packaged P comes into contact with and is sandwiched between the protrusion 51C, which maintains its original, uncrushed shape, adjacent to the protrusion 51A, which has been pressed against the object to be packaged P and has been completely crushed, thereby fixing the object to be packaged P and preventing lateral movement. Furthermore, these protrusions 51B and 51C provide a cushioning effect against external impacts.
[0024] Figure 12 is a perspective view of a sheet 60 with scattered protrusions used in the packaging method according to this embodiment. Figure 13 is a plan view of the sheet 60 with scattered protrusions used in the packaging method according to this embodiment. Figure 14 is a cross-sectional view taken along line A-A in Figure 13. As shown in Figure 12, the sheet 60 has a plurality of scattered protrusions 61. The cross-sectional shape of the protrusions in the sheet with scattered protrusions used in the packaging method according to this embodiment may be rectangular, such as a square or rectangle, or polygonal, such as a pentagon or hexagon. As shown in Figure 13, the cross-sectional shape (outer circumference shape) of the protrusions 61 scattered on the sheet 60 is square. As shown in Figure 14, the protrusions 61 are multi-stage protrusions having a three-stage structure: first stage 61f, second stage 61s, and third stage 61t. When an object to be packaged is pressed against such multi-stage protrusions, the protrusions of the stages that come into contact with the object to be packaged are easily crushed, and the shape crushed by the object to be packaged is maintained. From the perspective of preventing the packaged object from swaying side to side during packaging, the height H of the protrusion 61 61 This is the ratio to the height of the object to be packaged (height H of the protrusion 61). 61 The height of the object is preferably 0.2 or more, more preferably 0.33 or more, and even more preferably 0.5 or more. Also, the height H of the protrusion 61 61 The height H of the protrusion 61 may be preferably 0.1 cm to 5 cm, more preferably 0.2 cm to 0.4 cm, and even more preferably 0.3 cm to 3 cm. 61 This is the ratio of the cross-sectional shape of the protrusion 61 to the length of the side (height H of the protrusion 61). 61 The side length of the cross-sectional shape of the protrusion 61 is preferably 0.33 or more, more preferably 0.5 or more, and even more preferably 1 or more.
[0025] Also, the height H of the first stage of the protrusion 61 61f The height H of the first stage of the protrusion 61 may be preferably 0.1 cm to 1.4 cm, more preferably 0.2 cm to 1.3 cm, and even more preferably 0.3 cm to 1.2 cm. 61f This is the ratio of the side length of the cross-sectional shape of the first stage 61f of the protrusion 61 (the height H of the first stage of the protrusion 61). 61fThe length of the side of the cross-sectional shape of the first stage 61f of the protrusion 61 is preferably 0.066 or more, more preferably 0.2 or more, and even more preferably 0.33 or more. Also, from the viewpoint of making the protrusion 61 easier to crush when the object to be packaged is pressed against the protrusion 61, the height H of the second stage 61s of the protrusion 61 is... 61s The height H of the protrusion 61 is 61 Ratio to (second stage height H of the protrusion 61) 61s / H 61 The height H of the second stage 61s of the protrusion 61 is preferably 0.066 or more, more preferably 0.2 or more, and even more preferably 0.33 or more. 61s The height H of the second stage of the protrusion 61 may be preferably 0.1 cm to 1.4 cm, more preferably 0.2 cm to 1.3 cm, and even more preferably 0.3 cm to 1.2 cm. 61s This is the ratio of the side length of the cross-sectional shape of the first stage 61f of the protrusion 61 (the height H of the second stage of the protrusion 61). 61s The length of the side of the cross-sectional shape of the first stage 61f of the protrusion 61 is preferably 0.066 or more, more preferably 0.2 or more, and even more preferably 0.33 or more. Also, from the viewpoint of making the protrusion 61 easier to crush when the object to be packaged is pressed against the protrusion 61, the height H of the third stage 61t of the protrusion 61 is set. 61t The height H of the protrusion 61 is 61 Ratio to (Third stage height H of the protrusion 61) 61t / H 61 The height H of the third stage 61t of the protrusion 61 is preferably 0.066 or more, more preferably 0.2 or more, and even more preferably 0.33 or more. 61t The height H of the third stage 61t of the protrusion 61 may be preferably 0.1 cm to 1.4 cm, more preferably 0.2 cm to 1.3 cm, and even more preferably 0.3 cm to 1.2 cm. 61t This is the ratio of the side length of the cross-sectional shape of the first stage 61f of the protrusion 61 (height H of the third stage 61t of the protrusion 61). 61t The side length of the cross-sectional shape of the first stage 61f of the protrusion 61 is preferably 0.066 or more, more preferably 0.2 or more, and even more preferably 0.33 or more.
[0026] Next, the sheet with scattered protrusions used in the packaging method according to this embodiment will be described. The sheet may be a single-layer sheet, or it may be a multi-layer sheet with multiple layers such as two or three layers laminated together. Below, the single-layer sheet will be described first, and then the multi-layer sheet will be described. (1) Sheet
[0027] [Single-layer sheet]
[0028] When the sheet with scattered protrusions used in the packaging method according to this embodiment is a single-layer sheet, such a single-layer sheet may be formed from a resin composition. The resin composition may preferably contain a biomass material and a thermoplastic resin. In this embodiment, by including a biomass material, it is possible to obtain ease of crushing when crushing the protrusions scattered on the molded sheet and resistance to returning to their original shape after crushing, i.e., shape retention. Furthermore, by including a biomass material in the resin composition, the protrusions scattered on the molded sheet can be crushed without applying excessive force, thereby reducing the possibility of damaging the surface of the packaged object.
[0029] The biomass material is preferably a plant-derived biomass material, and more specifically, starch material and cellulose material. The starch material and cellulose material may be classified as waste biomass, unused biomass, or resource grain. The biomass material may also be of animal origin, for example, biologically derived calcium carbonate such as eggshells and scallop shells.
[0030] As the starch material, raw starch can be used, for example, underground starch and above-ground starch. Underground starch is starch accumulated underground, for example, starch accumulated in rhizomes or roots. Examples of underground starch include, but are not limited to, tapioca starch (cassava starch), potato starch, sweet potato starch, kudzu starch, and bracken starch.
[0031] Ground-based starches are starches accumulated on the ground, such as those accumulated in seeds. Examples of ground-based starches include, but are not limited to, corn starch, wheat starch, sago starch, acorn starch, and rice starch.
[0032] In the single-layer sheet, above-ground starch is preferably used.
[0033] The starch material may be a modified starch (i.e., modified starch), particularly a modified ground-based starch. Examples of such modified starches include chemically modified starches. Examples of chemically modified starches include acetoacetate esterified starch, acetate esterified starch, hydroxymethyl etherified starch, hydroxypropyl etherified starch, carboxymethyl etherified starch, allyl etherified starch, methyl etherified starch, succinate esterified starch, xanthogene acetate esterified starch, nitrate esterified starch, urea phosphate esterified starch, phosphate esterified starch, phosphate cross-linked starch, formaldehyde cross-linked starch, acrolein cross-linked starch, epichlorohydrin cross-linked starch, and the like.
[0034] When the starch material is corn starch, its particle size is preferably 5 μm or larger, more preferably 10 μm or larger, and even more preferably 15 μm or larger. The upper limit of the particle size is not particularly limited, but is preferably 50 μm or smaller, more preferably 40 μm or smaller, and even more preferably 30 μm or smaller.
[0035] Furthermore, when the starch material is tapioca starch, its particle size is preferably 2 μm or larger, more preferably 10 μm or larger, and even more preferably 15 μm or larger. The upper limit of the particle size is not particularly limited, but is preferably 40 μm or smaller, more preferably 30 μm or smaller, and even more preferably 25 μm or smaller.
[0036] When the starch material is potato starch, its particle size is preferably 2 μm or larger, more preferably 20 μm or larger, and even more preferably 30 μm or larger. The upper limit of the particle size is not particularly limited, but is preferably 80 μm or smaller, more preferably 60 μm or smaller, and even more preferably 40 μm or smaller.
[0037] Furthermore, the starch material may preferably contain equilibrium moisture. The amount of equilibrium moisture may be, for example, preferably 10% to 15% by mass, more preferably 10% to 14% by mass, even more preferably 10% to 13% by mass, and even more preferably 11% to 13% by mass, relative to the mass of the starch material. When compounded with a thermoplastic resin, the moisture content of the starch may preferably be 3% or less.
[0038] Examples of cellulose materials used in this embodiment include paper, paper pulp, cotton, or crushed cloth.
[0039] The particle size D50 (median diameter) of the cellulose material is, for example, 15 μm to 150 μm, and particularly preferably 20 μm to 100 μm. The particle size D50 is determined by wet measurement using a laser diffraction particle size distribution analyzer (SALD-3100, Shimadzu Corporation). By having a particle size within the above numerical range, the cellulose material can contribute to improving the dispersibility of the cellulose material contained in the thermoplastic resin.
[0040] Of the cellulose fibers constituting the cellulose material, the number of cellulose fibers having a particle size of 9.8 μm to 110.6 μm accounts for 65% to 100%, preferably 70% to 100%, more preferably 80% to 100%, and even more preferably 85% to 100% of the total number of cellulose fibers constituting the cellulose material. The above proportions regarding the number of cellulose fibers are determined by wet measurement using the laser diffraction particle size distribution analyzer to determine the proportion of cellulose fibers having a particle size of 0 μm to 9.8 μm (hereinafter referred to as the "first proportion") and the proportion of cellulose fibers having a particle size of 0 μm to 110.6 μm (hereinafter referred to as the "second proportion") out of the total number of cellulose fibers in the cellulose material, and then subtracting the first proportion from the second proportion. The numerical ranges "0 μm to 9.8 μm" and "0 μm to 110.6 μm" are both numerical ranges input to the laser diffraction particle size distribution analyzer during the wet measurement.
[0041] In this embodiment, particularly preferably, the number of cellulose fibers having a particle size of 110.6 μm to 998.4 μm among the cellulose fibers constituting the cellulose material accounts for 0% to 30%, preferably 0% to 25%, more preferably 0% to 20%, and even more preferably 0% to 15% of the total number of cellulose fibers constituting the cellulose material. The above proportions regarding the number of cellulose fibers are determined by wet measurement using the laser diffraction particle size distribution analyzer to determine the proportion of cellulose fibers having a particle size of 0 μm to 110.6 μm (the "second proportion" above) and the proportion of cellulose fibers having a particle size of 0 μm to 998.4 μm (hereinafter referred to as the "third proportion") among the total number of cellulose fibers in the cellulose material, and then subtracting the second proportion from the third proportion. The numerical ranges "0 μm to 110.6 μm" and "0 μm to 998.4 μm" are both numerical ranges input to the laser diffraction particle size distribution analyzer in the wet measurement.
[0042] A cellulose material having the above particle size distribution can be produced, for example, by treating pulp with a chemical such as an acid. An example of a cellulose material having the above particle size distribution is KC Floc W400 (Nippon Paper Industries Co., Ltd.). Using cellulose powder having the above particle size distribution provides better moldability when manufacturing sheets.
[0043] In particular, if the number of cellulose fibers having a particle size of 9.8 μm to 110.6 μm among the cellulose fibers constituting the cellulose powder accounts for 80% to 100%, and more preferably 85% to 100%, of the total number of cellulose fibers constituting the cellulose powder, it is possible to prevent tearing or the occurrence of holes in the sheet obtained by molding the thermoplastic resin. In order to prevent tearing or the occurrence of holes in the sheet, it is particularly preferable that the number of cellulose fibers having a particle size of 110.6 μm to 998.4 μm among the cellulose fibers constituting the cellulose powder accounts for 0% to 20%, and more preferably 0% to 15%, of the total number of cellulose fibers constituting the cellulose powder.
[0044] In another embodiment, the cellulose powder may have a particle size such that 90% or more of the particles pass through a 100-mesh grid. In this embodiment, more preferably, the cellulose powder has a particle size such that 90% or more of the particles pass through a 100-mesh grid, and the apparent specific gravity of the cellulose powder may be 0.30 g / ml to 0.40 g / ml.
[0045] The particle size is measured by the standard sieving method, specifically as follows: 10 g of the sample is placed in a 100-mesh standard sieve, a receiving tray and lid are set on the sieve, and the sample is shaken for 40 minutes using a rotary shaker. The particle size is then calculated from the sample mass (10 g) and the mass of the sieved residue using the following formula: Particle size (%) = [(Sample mass (g) - Sieved residue (g)) / Sample mass (g)] × 100
[0046] The apparent specific gravity is measured as follows: 10 g of the sample is accurately weighed on a balance and placed in a 50 ml graduated cylinder. The bottom of the graduated cylinder is tapped on a rubber-covered surface, taking care not to spill the sample. This tapping process is continued until no more sample can clog the cylinder. After tapping, the surface of the sample is flattened, and the scale (volume, ml) is read. The apparent specific gravity is then calculated using the following formula: Apparent specific gravity (g / ml) = Sample (10 g) / Volume (ml)
[0047] Cellulose powder having the above particle size (or the above particle size and apparent specific gravity) can be produced, for example, by mechanically grinding pulp (e.g., by jet mill grinding). An example of cellulose powder having the above particle size (or the above particle size and apparent specific gravity) is KC Floc 100GK.
[0048] In this embodiment, from the viewpoint of obtaining ease of crushing of the convex portions scattered on the formed sheet and resistance to returning to their original shape after crushing, the biomass material content is preferably 4% to 95% by mass, more preferably 6% to 93% by mass, and even more preferably 8% to 90% by mass, relative to the mass of the resin composition.
[0049] The thermoplastic resin used in the single-layer sheet according to this embodiment may be a polyolefin resin, a polyester resin, or a mixture of these resins. Alternatively, the thermoplastic resin may be a polystyrene resin. Furthermore, the thermoplastic resin may contain biodegradable materials to avoid reducing its biodegradability.
[0050] Polyolefin resins are polymers obtained by polymerization using olefins (e.g., α-olefins) as the main monomers. Polyolefin resins may be, for example, polyethylene (PE) resins or polypropylene (PP) resins, or combinations thereof. Furthermore, polyolefin resins may be homopolymers, block copolymers, or random copolymers.
[0051] The polyethylene resin may be, for example, low-density polyethylene resin (LDPE), high-density polyethylene resin (HDPE), very low-density polyethylene resin (VLDPE), linear low-density polyethylene resin (LLDPE), ethylene copolymers such as ethylene-vinyl acetate copolymer (EVA resin), or ultra-high molecular weight polyethylene resin (UHMW-PE), or a combination thereof.
[0052] The polyolefin resin may preferably be a biomass-derived polyolefin resin (for example, a biomass-derived polyethylene resin), and may be, for example, a biomass polyethylene resin. The biomass polyethylene resin may be, for example, LDPE, LLDPE, or HDPE. This can reduce CO2 emissions.
[0053] The polyolefin resin may be a polyolefin resin produced using a metallocene catalyst. That is, the thermoplastic resin may be, for example, a metallocene catalyst-based polyethylene resin or polypropylene resin, or a combination thereof. The polystyrene resin may be a metallocene catalyst-based polystyrene resin.
[0054] Polyester resins are polymers formed by the polymerization of monomers via ester bonds. Examples of polyester resins include polyethylene terephthalate resin (PET), polyethylene naphthalate resin (PEN), polybutylene terephthalate resin (PBT), polylactic acid resin (PLA), or polycarbonate resin (PC), polybutylene adipate terephthalate resin (PBAT), polybutylene succinate resin (PBS), polyhydroxyalkanoate resin (PHA), or combinations of two or more of these.
[0055] Polystyrene resins are polymers formed by the polymerization of styrene monomers. Polystyrene resins may include, for example, polystyrene resin, rubber-reinforced polystyrene resin (high-impact polystyrene resin, HIPS), acrylonitrile-styrene copolymer (AS resin), methacrylic acid ester-styrene copolymer, acrylonitrile-acrylic rubber-styrene copolymer, and acrylonitrile-ethylene propylene-styrene copolymer, or combinations of two or more of these.
[0056] In this embodiment, the type of thermoplastic resin may be appropriately selected by those skilled in the art, for example, depending on the packaging application, and a thermoplastic resin with a low processing temperature is preferred. For example, in the case of a sheet used for food packaging, the thermoplastic resin may be, for example, preferably a polyolefin resin, more preferably a polyethylene resin or a polypropylene resin, and even more preferably a polypropylene resin.
[0057] In this embodiment, the melting point of the thermoplastic resin is preferably 170°C or lower, and more preferably 165°C or lower. By using a thermoplastic resin with a lower melting point, the temperature during sheet molding can be reduced. Furthermore, the melting point of the thermoplastic resin is preferably 90°C or higher, and more preferably 95°C or higher.
[0058] As the thermoplastic resin, pelletized granular material may be used. The content of the thermoplastic resin is preferably 3% to 95% by mass, more preferably 5% to 93% by mass, and even more preferably 8% to 90% by mass, based on the mass of the resin composition.
[0059] Examples of the biodegradable materials include cellulose derivatives such as methylcellulose, hydroxymethylcellulose, hydroxyethylcellulose, hydroxypropylmethylcellulose, hydroxyethylmethylcellulose, and hydroxybutylmethylcellulose; hydrophilic polymer materials such as polyvinyl alcohol, carboxymethylcellulose, polyacrylic acid polymers, and polyacrylamide; emulsions such as various acrylates, ethylene / vinyl acetate copolymers, and polyurethanes; and aliphatic polyester resins such as caprolactone, polylactic acid, polybutylene adipate, polybutylene succinate, and polyhydroxybutyrate / variate copolymers.
[0060] When a single-layer sheet is used as the sheet with scattered protrusions in the packaging method according to this embodiment, the single-layer sheet may contain additives in addition to the biomass material and the thermoplastic resin. As such additives, low-melting-point additives that have a melting point lower than the melting temperature of the thermoplastic resin and melt at a relatively low temperature may be used. Preferably, such low-melting-point additives melt at 100°C or below, and more preferably melt at 60 to 100°C. As such low-melting-point additives, ester compounds that are liquid or solid at room temperature are preferably used. Specifically, examples of low-melting-point additives include monoglycerides, diglycerides, triglycerides, acetylated monoglycerides, organic acid monoglycerides, medium-chain fatty acid monoglycerides, polyglycerin fatty acid esters, sorbitan fatty acid esters, propylene glycol fatty acid esters, special fatty acid esters, and higher alcohol fatty acid esters. Preferably, glycerin-based fatty acid esters are used. Low-melting-point additives melt at relatively low temperatures, possess viscosity, and can function to entangle and adhere to biomass material powders.
[0061] The low-melting-point additive may be blended in a proportion of, for example, preferably 0.1 to 5 parts by mass, more preferably 0.1 to 3 parts by mass, per 100 parts by mass of biomass material.
[0062] Furthermore, the low-melting-point additive may be included in the resin composition in a content ratio of, for example, preferably 0.1% to 5% by mass, and more preferably 0.1% to 3% by mass, relative to the mass of the resin composition.
[0063] Furthermore, the resin composition may contain a high-melting-point additive having a higher melting point than the low-melting-point additive. Such a high-melting-point additive may have a higher melting point than the low-melting-point additive, preferably in the range of 100 to 150°C, solidify before the low-melting-point additive, and have a melting point lower than the melting temperature of the thermoplastic resin. Examples of such high-melting-point additives include fatty acid metal salts, hydrocarbons, higher alcohols, aliphatic amides, and fatty acid esters. Specifically, magnesium stearate, zinc stearate, calcium stearate, aluminum stearate, sodium lauryl sulfate, magnesium lauryl sulfate, potassium benzoate, sodium benzoate, and sodium stearyl fumarate are used.
[0064] The high-melting-point additive may be included in the resin composition in a content ratio of, for example, preferably 0.1% to 10% by mass, more preferably 0.1% to 5% by mass, relative to the mass of the resin composition.
[0065] Other additives that can be used include compatibilizers to improve the affinity between biomass materials and thermoplastic resins. The compatibilizer may be selected depending on the type of thermoplastic resin. Examples of such compatibilizers include acid-modified polyolefins, acid-modified nylons, acid-modified polystyrenes, acid-modified EVA, acid-modified ethylene copolymers, acid-modified acrylates, acrylic acid-modified EVA, and modified ethylene acrylates.
[0066] When the thermoplastic resin is a polyolefin-based resin, the compatibilizer is preferably an acid-modified polyolefin, and in particular may be a carboxylic acid anhydride-modified polyolefin or an olefin-based comonomer.
[0067] The carboxylic acid anhydride constituting the carboxylic acid anhydride-modified polyolefin is preferably maleic anhydride. The compatibilizer is, for example, a maleic anhydride-grafted polyolefin resin, and more particularly, one or more combinations selected from the group consisting of maleic anhydride-modified polyethylene, maleic anhydride-modified polypropylene, and maleic anhydride-modified ethylene-propylene copolymer. A rubber component may be dispersed in the compatibilizer.
[0068] The compatibilizer may be included in the resin composition in an amount of, for example, 0.1% to 10% by mass, more preferably 1.0% to 5.0% by mass, relative to the mass of the resin composition.
[0069] Other additives that can be used include colorants.
[0070] Colorants can be used to color resin compositions. Examples of colorants include titanium dioxide, carbon black, dyes, and pigments.
[0071] Inorganic fillers can be used as other additives. Inorganic powders are examples of inorganic fillers. For example, shell powder and mineral powder are preferably used as inorganic powders. The specific gravity of the inorganic powder used is preferably 2.5 g / cm³. 3 More preferably, 2.55 g / cm³ 3 More preferably, 2.6 g / cm³ 3 More preferably, 2.65 g / cm³ 3 That's all.
[0072] Shell powder refers to a powder made by crushing shells. The shells used are not particularly limited, and can include shells of scallops, oysters, surf clams, abalone, mussels, clams, and cockles. Shell powder may be obtained, for example, by washing and sterilizing shells discarded from food factories and then crushing them, or it may be obtained from shells of shellfish not used for food purposes. The method of crushing the shells is not particularly limited, and any known crushing method may be appropriately selected and adopted, and it may be either wet or dry. Alternatively, the shells may be pre-crushed in a coarse crusher and then powdered in a pulverizer. Specifically, coarse crushers include jaw crushers, cone crushers, cutter mills, and hammer crushers, and pulverizers include roll mills, stamp mills, hammer mills, ball mills, vibrating ball mills, roller mills, and vertical mills. Preferably, the shell powder is scallop shell powder. Examples of scallop shell powder include uncalcined scallop shell powder and calcined scallop shell powder. Uncalcined scallop shell powder is made by grinding natural scallop shells into a powder and keeping them in an uncalcined state. Its main component (approximately 96%) is usually calcium carbonate. Uncalcined scallop shell powder is available commercially.
[0073] Examples of mineral powders include clay mineral powder. Such clay mineral powders can be either natural or synthetic. Examples of clay mineral powders include calcium carbonate, magnesium carbonate, zinc oxide, titanium oxide, silica, alumina, clay, talc, kaolin, aluminum hydroxide, magnesium hydroxide, aluminum silicate, magnesium silicate, calcium silicate, aluminum sulfate, magnesium sulfate, calcium sulfate, magnesium phosphate, barium sulfate, silica sand, carbon black, zeolite, molybdenum, diatomaceous earth, sericite, shirasu, calcium sulfite, sodium sulfate, potassium titanate, bentonite, wollastonite, dolomite, and graphite. Among these, talc powder is particularly preferred. As for inorganic powders, only seashell powder may be used, only mineral powder may be used, or a mixture of seashell powder and mineral powder may be used.
[0074] Furthermore, other components such as antioxidants, crosslinking agents, UV absorbers, foaming agents, and impact absorbing agents may be used. Commercially available additives may be used for these purposes.
[0075] [Multilayer sheet]
[0076] Next, when a multilayer sheet is used as the sheet with scattered protrusions in the packaging method according to this embodiment, the multilayer sheet will be described with reference to the drawings. Figure 15 is an example of a multilayer sheet used as the sheet with scattered protrusions in the packaging method according to this embodiment, and is a two-layer sheet composed of layer A and layer B. As shown in Figure 15, in the two-layer multilayer sheet, layer A is formed from a resin composition containing a polyolefin resin. The polyolefin resin has been described in the single-layer sheet above, so its description will be omitted. In layer A, the polyolefin resin contained in the resin composition is preferably 70% by mass or more, more preferably 80% by mass or more, even more preferably 90% by mass or more, and may be 100% by mass, based on the mass of the resin composition. Layer B is formed from a resin composition containing a biomass material and a thermoplastic resin, etc., as described in the single-layer sheet above. The resin composition has also been described above, so its description will be omitted. In the two-layer multilayer sheet, either layer A or layer B may be on the protrusion surface side.
[0077] Furthermore, the multilayer sheet used in the packaging method according to this embodiment may be a three-layer sheet. Figure 16 shows an example of such a three-layer sheet, consisting of layer A, layer B, and layer A. As shown in Figure 16, it has a structure in which layer B is the intermediate layer and layer A is laminated on both sides of the intermediate layer as the outer layer. Figure 17 shows another example of a three-layer sheet, consisting of layer A, layer B, and layer C. As shown in Figure 17, it has a structure in which layer B is the intermediate layer and layer A and layer C are laminated on both sides of the intermediate layer as the outer layer. Layers A and B are as described in the single-layer sheet above, so their description is omitted. Layer C is a compound layer formed from a polyolefin resin. In the three-layer multilayer sheet, either layer A or layer C may be on the convex surface side.
[0078] (2) Method for manufacturing the sheet
[0079] [Method for manufacturing a single-layer sheet]
[0080] When the sheet with scattered protrusions used in the packaging method according to this embodiment is a single-layer sheet, the manufacturing method of such a single-layer sheet may include: a biomass material drying step in which biomass material is placed in a container equipped with a heating element on the outside, and the biomass material is dried while the inside of the container is heated by the heating element, thereby preventing the biomass material from adhering to the inner surface of the container; a resin composition preparation step in which the biomass material dried in the biomass material drying step is mixed with a thermoplastic resin to prepare a resin composition; and a molding step in which the resin composition prepared in the resin composition preparation step is molded to obtain a sheet with scattered protrusions.
[0081] The method for manufacturing the single-layer sheet may include a biomass material drying step (S1), a resin composition preparation step (S2), and a molding step (S3). Each step will be described below.
[0082] <Biomass material drying process (S1)>
[0083] In the biomass material drying process (S1), the biomass material is placed inside a container. The container in which the biomass material is placed is equipped with an external heating element that heats the inside of the container. Examples of such containers include a heating agitator having a heating jacket around a cylindrical container made of stainless steel or steel. In such a heating agitator, the outer circumference of the containment section in which the biomass material is placed is covered with a heating jacket. Agitation blades are provided inside the containment section. The heating jacket is filled with a heat transfer medium such as oil, hot water, or heated steam, and the heating jacket can function as a heating element. The heating jacket heats the containment section inside the container by heating the inner surfaces such as the inner walls, lid, and bottom surfaces of the container. The heating jacket heats the inner surfaces inside the container so that there are no areas that are not sufficiently heated. By ensuring that there are no areas that are not sufficiently heated inside the container, condensation of moisture in the biomass material evaporated by heating is suppressed from coming into contact with areas that are not sufficiently heated. By suppressing condensation on the inner surface of the heating agitator, the biomass material contained in the container, which prevents starch and other biomass materials from gelatinizing and adhering to the inner surface of the heating agitator, is dried within the heated container. Furthermore, during the drying of the biomass material, gelatinization of starch and other biomass materials can be prevented and drying efficiency can be improved by continuously moving the biomass material using stirring blades. The shape of the stirring blades 12 can be selected from any shape such as propeller blades, paddle blades, inclined paddle blades, turbine blades, screw blades, anchor blades, ribbon blades, and large grid blades. Such a heating agitator is also called an external heating jacket type mixer.
[0084] In this process, from the viewpoint of efficiently drying the biomass material, the temperature inside the container is preferably 120°C or higher, more preferably 135°C or higher, and even more preferably 150°C or higher. Furthermore, from the viewpoint of suppressing thermal degradation of the biomass material, the temperature inside the container is preferably 200°C or lower, more preferably 190°C or lower, and even more preferably 180°C or lower.
[0085] For stirring, the rotation speed of the stirring blades may be set to preferably 500 to 2000 rpm, more preferably 750 to 1750 rpm, and even more preferably 1000 to 1500 rpm.
[0086] In this process, the drying time for the biomass material is not limited, but can be set appropriately depending on the amount of biomass material from the viewpoint of drying efficiency. For example, it may be preferably 10 to 30 minutes, more preferably 15 to 30 minutes, and even more preferably 15 to 25 minutes.
[0087] In this process, the biomass material is prevented from adhering to the inner surface of the container where it is contained. When the biomass material is heated inside the container, the water contained in the biomass material evaporates. The evaporated water comes into contact with areas on the inner surface of the container, such as the inner wall surface, the inner surface of the lid, and the bottom surface, where the temperature rise due to heating is insufficient, causing condensation. When the biomass material contained inside the container adheres to the inner surface of the container where condensation has occurred, the biomass material is heated in the presence of water. For example, if the biomass material is starch, water enters the molecular chain of the starch under heating, causing the molecular structure to loosen and swell (alpha-gelatinization), resulting in granular material known as "white grains." In the infrared absorption spectrum, "white grains" have an absorption peak derived from starch. Such an absorption peak is a peak derived from OH bonds, and the peak is located in the range of 3000 to 3500 cm⁻¹. Also, "white grains" do not color when stained with iodine. Typically, starch particles have a major axis of 10-20 μm, while granular material referred to as "white grains" has a major axis of 100-200 μm, which is larger than ungelatinized starch particles. Unungelatinized starch refers to starch that has not gelatinized before heating or even after heat drying treatment. Such "white grains" can cause mesh clogging and inclusion of white grains in the sheet during sheet or film extrusion molding, leading to brown discoloration, and can also cause holes in the resulting molded product during molding. In this process, the inside of the container is heated by an externally provided heating element, ensuring that there are no areas on the inner surface of the container where the temperature rise is insufficient. This suppresses condensation and prevents the biomass material inside the container from adhering to the inner surface. By preventing the biomass material from adhering to the inner surface of the container in this way, the generation of white grains can be suppressed, making it possible to efficiently manufacture molded products with superior quality. Furthermore, stirring the biomass material inside the container to prevent it from accumulating in one place is also preferable to suppress the biomass material from adhering to the inner surface of the container.
[0088] The above describes the use of an externally heated jacketed mixer, but in the biomass material drying process (S1) in this embodiment, a heated jacketed vacuum dryer may also be used. This dryer preferably has an external heating jacket and stirring blades inside the container, and the biomass material can be dried by creating a vacuum inside the container.
[0089] When using a heated jacket type vacuum dryer, from the viewpoint of efficiently drying the biomass material, the temperature inside the container is preferably 100°C or higher, more preferably 115°C or higher, and even more preferably 130°C or higher. Furthermore, from the viewpoint of suppressing thermal degradation of the biomass material, the temperature inside the container is preferably 200°C or lower, more preferably 185°C or lower, and even more preferably 170°C or lower.
[0090] The vacuum level inside the container is preferably set to 5 kPa to 30 kPa, more preferably to 5 kPa to 25 kPa, and even more preferably to 5 kPa to 20 kPa.
[0091] In this process, the drying time for the biomass material is not limited, but can be appropriately set depending on the amount of biomass material from the viewpoint of drying efficiency. For example, it is preferably 30 to 90 minutes, more preferably 40 to 80 minutes, and even more preferably 50 to 70 minutes. In this process, the biomass material may be dried to a moisture content of preferably 5% or less, more preferably 2% or less.
[0092] <Resin composition preparation step (S2)>
[0093] In the resin composition preparation step (S2), the biomass material dried in the drying step (S1) and the thermoplastic resin are mixed in an extruder to prepare the resin composition. In this step, when mixing the dried biomass material and the thermoplastic resin, for example, the dried biomass material and the thermoplastic resin may be simply mixed in a dry state to prepare a resin composition which is a mixture of powdered biomass material and pelletized thermoplastic resin. Alternatively, the dried biomass material and thermoplastic resin may be simultaneously fed into the extruder via a feeder, and the biomass material and thermoplastic resin may be uniformly kneaded and mixed by heating and kneading while controlling the rotation speed, stirring time, and temperature, thereby forming a resin composition from the molten and kneaded mixture of biomass material and thermoplastic resin present in the extruder. Furthermore, the molten and kneaded mixture of biomass material and thermoplastic resin may be extruded from the extruder, cooled, and pelletized to form the resin composition. A single-screw extruder or a twin-screw extruder can be used as such an extruder. Furthermore, when feeding biomass material and thermoplastic resin into the extruder, additives may be added at the same time. Examples of such additives include low-melting-point additives and high-melting-point additives. Alternatively, the biomass material, thermoplastic resin, and additives may each be fed individually via a feeder in predetermined proportions.
[0094] When mixing the biomass material and the thermoplastic resin in an extruder, the heating temperature (cylinder temperature) may be set to a temperature below the melting point of the thermoplastic resin, or above the melting point of the high-melting-point additive, from the viewpoint of suppressing material deterioration and discoloration. For example, the heating temperature (cylinder temperature) may be set to 100 to 190°C.
[0095] <Molding process (S3)>
[0096] In this process, the resin composition prepared in the resin composition preparation step (S2) is molded to obtain a sheet. For example, in the resin composition preparation step (S2), biomass material and thermoplastic resin are sufficiently heated and mixed in an extruder to prepare a resin composition. The resin composition is then transferred to a molding machine, and the resin composition is molded using the molding machine to form a sheet. The temperature used for molding the sheet may preferably be set to a temperature above the melting temperature of the thermoplastic resin, for example, 150 to 450°C, and the molding pressure may be set appropriately. The formed sheet is further molded using a vacuum molding machine to obtain a sheet with scattered protrusions. An example of such a vacuum molding machine is the WAKITEC FVS-500P (Wakisaka Engineering Co., Ltd.). The shape of the mold used in the vacuum molding machine can be matched to the shape of the protrusions to be formed on the sheet to create protrusions of the required shape on the sheet surface. Alternatively, the protrusions may be created simultaneously with the sheet molding.
[0097] <Biomass material cooling process (S4)>
[0098] In the method for manufacturing the single-layer sheet, a biomass material cooling step (S4) may be provided between the biomass material drying step (S1) and the resin composition preparation step (S2). This step can be carried out, for example, using a manufacturing apparatus having a heating stirrer, a cooling stirrer, and an extruder.
[0099] The biomass material and thermoplastic resin are heated and stirred in a heating agitator. Alternatively, the biomass material, thermoplastic resin, and low-melting-point additive may be heated and stirred in the heating agitator. After that, the mixture of biomass material and thermoplastic resin may be transferred to a cooling agitator and cooled while being stirred in the cooling agitator to a temperature above the melting temperature of the low-melting-point additive, and close to its melting temperature. Alternatively, the mixture of biomass material and thermoplastic resin may be cooled without stirring.
[0100] [Manufacturing method for multilayer sheets]
[0101] If the sheet with scattered protrusions used in the packaging method according to this embodiment is a multilayer sheet, the method for manufacturing the multilayer sheet may include: a biomass material drying step in which biomass material is placed in a container equipped with an external heating element, and the biomass material is dried by stirring while the inside of the container is heated by the heating element; a resin composition preparation step in which the biomass material dried in the biomass material drying step is mixed with a thermoplastic resin to prepare a resin composition; and a multilayer extrusion molding step in which the resin composition prepared in the resin composition preparation step and a resin composition of a different type from the resin composition are multilayer extruded together to obtain a laminate in which different types of resin layers are stacked.
[0102] The method for manufacturing the multilayer sheet may include a biomass material drying step (S1), a resin composition preparation step (S2), and a multilayer extrusion molding step (S6). It may also include a biomass material cooling step (S4). Note that the biomass material drying step (S1), the resin composition preparation step (S2), and the biomass material cooling step (S4) are the same steps as in the method for manufacturing a single-layer sheet, so their explanation will be omitted. The multilayer extrusion molding step (S6) will be described below.
[0103] <Multilayer extrusion molding process (S6)>
[0104] In the multilayer extrusion molding process (S6), a resin composition of a different type from the resin composition is extruded and molded so that different types of resin layers are stacked on top of each other to obtain a laminate. The laminate can be obtained, for example, using a multilayer co-extrusion molding machine. The multilayer co-extrusion molding machine may have an extruder for layer A, an extruder for layer B, an extruder for layer C, a feed block, and dies. Using the multilayer co-extrusion molding machine, a three-layer structure sheet is co-extruded in which layers A, B, and C are stacked, with layer B containing biomass material as the middle layer and layers A and C as the surface layers. The extruder for layer B extrudes the resin composition prepared in the resin composition preparation process (S2), and the extruder for layer A and the extruder for layer C each extrude a thermoplastic resin composition of a different type from the resin composition extruded from the extruder for layer B. When manufacturing a two-layer sheet consisting of layer A and layer B, for example, the sheet is formed using the extruder for layer A and the extruder for layer B. Furthermore, when manufacturing a three-layer sheet in which layer B is the intermediate layer and layer A is the outer layer, for example, an extruder for layer A, an extruder for layer B, and an extruder for layer C are used, and the resin composition used for the extruder for layer B is supplied to the extruder for layer C to form the three-layer sheet. The same method as for a single-layer sheet may be used to scatter protrusions on the sheet, and the protrusions can be formed simultaneously on layers A, B, and C.
[0105] (3) Purpose
[0106] The sheet used in the packaging method of this embodiment can fix the object to be packaged within the packaging container during transportation of goods or products, preventing lateral shaking due to vibration, etc. Furthermore, regardless of the shape of the object to be packaged, when packaging the object to be packaged in the packaging container, pressing the object to be packaged against the protrusions of the sheet crushes all or part of the protrusions, and the object to be packaged is sandwiched (gripped) between the fully crushed protrusions, the partially crushed protrusions, and the protrusions that maintain their original shape, thereby fixing the object to the sheet. In other words, with the packaging method of this embodiment, there is no need to prepare cushioning material in advance to conform to the shape of the object to be packaged. Figure 18 is a perspective view showing the object to be packaged P pressed from above along the thickness direction onto the sheet 60. Figure 19 is a cross-sectional view taken along line A-A in Figure 18. As shown in Figures 18 and 19, by pressing the object to be packaged P onto the sheet 60 from above along the thickness direction, the protrusions scattered on the sheet 60 are crushed. The convex portion 61A that is completely crushed and the convex portion 61B that is partially crushed by the object to be packaged P retain their crushed shape, while the convex portion 61C in the surrounding area that is not pressed against by the object to be packaged P maintains its original, uncrushed shape. The object to be packaged P is held (gripped) and fixed in place by the convex portion 61A that retains its crushed shape, the convex portion 61B that is partially crushed, and the convex portion 61C that maintains its original, uncrushed shape.
[0107] In the packing method described above, one sheet with scattered protrusions is prepared and used to secure the object to be packed. However, depending on the size and shape of the object to be packed, multiple sheets with scattered protrusions may be prepared and used to secure the object. For example, in the packing method, the object to be packed may be sandwiched between sheets with scattered protrusions on the top and bottom. Alternatively, the object to be packed may be sandwiched between sheets with scattered protrusions on the left and right. Furthermore, the object to be packed may be sandwiched between sheets with scattered protrusions on all sides, or the object to be packed may be wrapped with sheets with scattered protrusions. More specifically, two sheets with scattered protrusions may be prepared in advance, and the object to be packed may be sandwiched between the top and bottom in the thickness direction using these sheets. Figure 20 schematically shows how the object to be packed P is sandwiched between sheets 60 with scattered protrusions on the top and bottom. In Figure 20, the arrows indicate the direction in which the sheets 60 are pressed against the object to be packed P. Note that in Figure 20, the protrusions scattered on the sheet 60 are not shown.
[0108] Alternatively, instead of pressing the sheet against the object to be packaged in the vertical direction, two sheets with scattered protrusions may be prepared in advance, and a pair of two sides of the object to be packaged, perpendicular to the thickness direction, may be sandwiched between the sheets from the left and right directions. Figure 21 schematically shows how a pair of two sides of the object to be packaged P are sandwiched between sheets 60 with scattered protrusions from the left and right directions. In Figure 21, the arrows indicate the direction in which the sheet 60 is pressed against the object to be packaged P. In Figure 21, a pair of two sides of the object to be packaged P are sandwiched between the sheets from the left and right directions, but two more sheets with scattered protrusions may be prepared, and the remaining pair of two sides of the object to be packaged P may be sandwiched between the sheets from the left and right directions. In other words, all four sides of the object to be packaged P may be sandwiched between the sheets.
[0109] In the packing method described above, the required number of sheets with dotted protrusions are prepared and pressed against the object to be packed from the top / bottom direction or from the left / right direction. However, the object to be packed may also be pressed against from the top / bottom direction and from the left / right direction. Figure 22 schematically shows how the sheets 60 with dotted protrusions are pressed against the object to be packed P from the top / bottom direction, and how the sheets 60 with dotted protrusions are pressed against a pair of two of the four sides of the object to be packed P from the left / right direction. In Figure 22, the arrows indicate the direction in which the sheets 60 are pressed against the object to be packed P. In Figure 22, the object to be packed P is sandwiched between the sheets from the top / bottom direction and a pair of two of the four sides from the left / right direction. However, two more sheets with dotted protrusions may be prepared and the remaining pair of two sides of the object to be packed P may also be sandwiched between the sheets from the left / right direction.
[0110] Furthermore, if the cross-sectional shape of the object to be packaged is circular or elliptical in plan view, a sheet with scattered protrusions may be wrapped around the object to be packaged. More specifically, a sheet with scattered protrusions may be wrapped around the outer circumference of the cross-sectional shape of the object to be packaged in plan view. By wrapping a sheet with scattered protrusions around the object to be packaged, the protrusions on the sheet are crushed by the object to be packaged, thereby fixing the object to be packaged.
[0111] [Packaging container]
[0112] Examples of packaging containers include those formed from a container section and a lid section, which house the object to be packaged and a sheet with dotted protrusions inside. More specifically, examples include boxes and bags, and boxes are usually used. Examples of materials for the packaging container include paper and resin. In the packaging method of this embodiment, the object to be packaged may be fixed to the sheet with dotted protrusions as described above, and the object to be packaged, which is fixed to the sheet with dotted protrusions, may be housed inside the container section. Alternatively, the sheet with dotted protrusions and the object to be packaged may be housed inside the container section, and then the object to be packaged may be pressed against the sheet with dotted protrusions inside the container section to fix it in place. The lid section may also be provided with a mechanism to close the lid section and the container section so that it cannot be opened after being closed. As a mechanism for closing the lid and container and preventing them from opening after closing, for example, a recess may be provided on the container-side surface of the lid so as to fit the outer circumference of the outer edge of the upper end surface of the container, with the width of the end of the container being the bottom of the recess, and the end of the container becoming a convex portion that engages with the recess, thereby preventing the lid from opening after closing the container. The recess may be provided around the entire outer circumference of the outer edge of the upper end surface of the container, or the convex portion and recess may be provided adjacent to each other along the outer circumference of the outer edge of the upper end surface of the container, and the recess of the lid may be provided at intervals so that the convex portion of the outer edge of the upper end surface of the container fits with the recess of the lid. In the second, third, and fourth embodiments as well, the lid may be provided with a mechanism for closing the lid and container and preventing them from opening after closing.
[0113] In the packaging method of this embodiment, in order to suppress vertical shaking of the object to be packaged, a top-seal packaging method may be adopted in which the container portion and the film are bonded or heat-sealed at the upper end surface of the container portion instead of the lid portion described above. That is, by bonding or heat-sealing the container portion and the film at the upper end surface of the container portion, the upper end surface of the object to be packaged, opposite to the sheet side, is covered with the film, and the object to be packaged is pressed against the protrusions by the film, thereby fixing the object to be packaged and suppressing vertical shaking. Figure 26 is a schematic cross-sectional view showing the state in which the upper end surface PU of the object to be packaged P is covered with film F. As shown in Figure 26, a sheet 60 with protrusions 61 (61A, 61B, 61C) scattered on it is placed on the bottom surface of the container portion 70. The object to be packaged P is pressed against the protrusions 61 of the sheet 60, which has scattered protrusions. When the protrusions 61 are crushed, the protrusions 61A and 61B maintain the crushed shape caused by the object to be packaged P, and the object to be packaged P is fixed in place by the crushed shape of the protrusions 61A and 61B and / or the protrusion 61C which maintains its original, uncrushed shape. It is preferable that the upper end surface of the object to be packaged protrudes from the peripheral edge of the upper end surface of the container portion in order to suppress vertical shaking of the object to be packaged during transport, etc. As shown in Figure 26, the vertical protrusion distance H between the upper end surface PU of the object to be packaged P and the peripheral edge 71 of the upper end surface of the container portion 70. V It is preferable that the value is greater than 0. Protrusion distance H V If the value is greater than 0, the film F is elastically deformed by the upper surface PU of the object being packaged, and the force of this elastic deformation returning to its original state allows the object P to be pressed down from above.
[0114] Figure 27 schematically shows a state in which a gap is created between the upper surface of the object to be packaged and the film. More specifically, as shown in Figure 27, the upper surface of the object to be packaged is lower than the peripheral edge of the upper surface of the container portion, and the upper surface of the object to be packaged does not protrude from the peripheral edge of the upper surface of the container portion. As shown in Figure 27, the upper surface PU of the object to be packaged P is lower than the peripheral edge 71 of the upper surface of the container portion 70, and the distance H between the film F and the upper surface PU of the object to be packaged P is... PUIf the value is greater than 0, a gap will be created between the film F and the upper surface PU of the object to be packaged P, preventing the film F from pressing down on the object to be packaged P from above, and thus preventing the vertical movement of the object to be packaged from being suppressed during transportation, etc.
[0115] The resin used in the film for top-seal packaging is not particularly limited, but examples include polyester resins such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate; polyolefin resins such as polypropylene, polyethylene, and polymethylpentene; polyamide resins such as nylon; acrylic (methacrylic) resins; diene resins such as polybutadiene; and thermoplastic resins such as polycarbonate resins.
[0116] 2. Second Embodiment (Another Example of Packaging Method)
[0117] In the packaging method of this embodiment, first, a sheet with scattered protrusions and a packaging container are prepared. The sheet with scattered protrusions is the same sheet described in the first embodiment. Therefore, a description of the sheet with scattered protrusions is omitted.
[0118] In this embodiment, the protrusions of the sheet are pre-flattened to match the shape of the object to be packaged, so that the object to be packaged can be secured by the flattened protrusions and / or the protrusions that maintain the original shape. The object to be packaged is then placed in the flattened area, and the contour portion of the object's shape is sandwiched (gripped) and secured by the flattened protrusions and / or the protrusions that maintain the original shape.
[0119] The sheet with scattered protrusions used in the packaging method of this embodiment can have its protrusions returned to their original shape by applying external force from the back of the crushed protrusions. This will be explained with the help of photographs. Figure 23 is a photograph taken from the back of the surface of the sheet 50 that contacts the object to be packaged, after the object to be packaged has been pressed against the sheet 50 and the protrusions 51A have been completely crushed. Figure 24 is a photograph taken from the back of the crushed protrusions 51A after the crushed area has been pressed with a finger to restore the shape of the protrusions 51A. Figure 25 is a photograph taken of the protrusions 51A whose shape has been restored by a finger.
[0120] The sheet with scattered protrusions used in the packaging method of this embodiment has the function of preventing the packaged object from swaying from side to side even after the protrusions have returned to their original shape before being crushed. When the packaged object is pressed against the protrusions, the protrusions maintain a shape in which the entire protrusion is crushed or a shape in which only a part of the protrusion is crushed. The packaged object is then sandwiched and fixed between the crushed protrusions and / or the protrusions that maintain their original, uncrushed shape. In other words, the sheet with scattered protrusions used in the packaging method of this embodiment has the function of preventing the packaged object from swaying from side to side even after being used multiple times.
[0121] Furthermore, in the packaging method of this embodiment, all the protrusions on a sheet with scattered protrusions are flattened in advance, the object to be packaged is placed on the flattened protrusions, and then the back of the flattened protrusions is pressed to restore their shape to match the shape of the object to be packaged, and the object to be packaged is sandwiched and secured by the flattened protrusions and / or the protrusions that maintain their original, unflattened shape. More specifically, the back of the flattened protrusions that are present in the contour portion of the shape of the object to be packaged is pressed to restore their shape, and the object to be packaged is sandwiched and secured by the flattened protrusions and / or the protrusions that maintain their original, unflattened shape.
[0122] In the packaging method of the first embodiment and the packaging method of the second embodiment, the object to be packaged may be fixed manually or automatically. To fix the object to be packaged manually, for example, the required number of sheets with protrusions may be prepared, and the object to be packaged may be manually pressed onto the sheets with the protrusions, crushing the protrusions and fixing the object to be packaged. Alternatively, the protrusions of the sheet may be crushed manually in advance by the packaging worker to match the shape of the object to be packaged, and the object to be packaged may be placed in the crushed areas by the packaging worker. Furthermore, all the protrusions of the sheet with the protrusions may be crushed manually in advance by the packaging worker, and after the packaging worker places the object to be packaged on the crushed protrusions, the packaging worker may manually press the back of the crushed protrusions to match the shape of the object to be packaged, and the object to be packaged may be sandwiched and fixed between the crushed protrusions and / or the protrusions that maintain their original, uncrushed shape.
[0123] Furthermore, in the above-described packaging method, in order to automatically secure the object to be packaged, for example, a required number of sheets with protrusions may be prepared, and a signal may be sent from a power source control unit, which has predetermined pressing pressure and pressing time set, to various power sources such as air cylinders, hydraulic cylinders, and magnetic solenoids, and these power sources may press the object to be packaged against the sheets with the protrusions. Alternatively, a signal may be sent from a power source control unit, which has predetermined crushing position, pressing pressure, and pressing time set, to the power source so that the power source can crush the protrusions of the sheet according to the shape of the object to be packaged, and the object to be packaged may be placed in the crushed area. Furthermore, a signal is sent from the power source control unit to the power source, where the crushing position, pressing pressure, and pressing time are set, so that the power source can crush all the protrusions on the sheet which has protrusions scattered on it. After the power source crushes all the protrusions on the sheet and places the object to be packaged on the crushed protrusions, the power source presses the back of the crushed protrusions to match the shape of the object to be packaged, and the object to be packaged is sandwiched and fixed between the crushed protrusions and / or the protrusions that maintain their original, uncrushed shape.
[0124] 3. Third Embodiment (Another Example of Packaging Method)
[0125] In the packaging method of the first embodiment and the packaging method of the second embodiment, a sheet with scattered protrusions and a container portion for containing the object to be packaged were prepared separately and assembled by combining them. However, in the packaging method of this embodiment, a packaging container is formed from a single sheet, comprising a bottom portion with scattered upward-pointing protrusions and a container portion extending vertically along the outer circumference of the bottom portion. Furthermore, in the packaging method of this embodiment, the packaging container may also include a lid portion that closes the opening on the upper end surface of the container portion.
[0126] In the packaging method of this embodiment, for example, a vacuum forming method may be used as a method for forming the packaging container.
[0127] Figure 28 is a schematic cross-sectional view of a packaging container formed from a single sheet, comprising a bottom surface with scattered upward-pointing protrusions and a container section extending vertically along the outer circumference of the bottom surface. As shown in Figure 28(A), the packaging container comprises a bottom surface 80 with scattered protrusions 81 and a container section 90. Figure 28(B) shows how the object to be packaged P is pressed against the protrusions 81 scattered on the bottom surface 80 of the packaging container in Figure 28(A), and how the object to be packaged P is placed inside the container section 90. As shown in Figure 28(B), by pressing the object to be packaged P from above against the bottom surface 80 along the thickness direction, the protrusions 81 scattered on the bottom surface 80 are crushed. The protrusions 81A that are completely crushed and the protrusions 81B that are partially crushed by the object to be packaged P retain their crushed shape. The object to be packaged P is held and fixed in place by a convex portion 81A that maintains its crushed shape and a partially crushed convex portion 81B.
[0128] Figure 29 is a schematic cross-sectional view of a packaging container formed from a single sheet, comprising a bottom portion with scattered upward-pointing protrusions, a container portion extending vertically along the outer circumference of the bottom portion, and a lid portion that closes the opening on the upper end surface of the container portion. As shown in Figure 29(A), the packaging container comprises a bottom portion 100 with scattered protrusions 101, a container portion 110, and a lid portion 130 that closes the opening on the upper end surface of the container portion 110. The lid portion 130 and the container portion 110 are connected by a hinge portion 102, and the hinge portion 102 is bent so that the lid portion 130 closes the opening on the upper end surface of the container portion 110. The upper end surface 120 of the lid portion 130 has scattered protrusions 121 that extend toward the bottom portion 100 when the opening on the upper end surface of the container portion 110 is closed with the lid portion 130. Figure 29(B) is a schematic cross-sectional view showing the packaging object P being pressed against the protrusions 101 scattered on the bottom surface 100 of the packaging container in Figure 29(A), while the opening on the upper end surface of the container 110 is closed with the lid 130.
[0129] As shown in Figure 29(B), by pressing the object to be packaged P against the bottom surface 100 from above along the thickness direction, the protrusions 101 scattered on the bottom surface 100 are crushed. The protrusions 101A that are completely crushed and the protrusions 101B that are partially crushed by the object to be packaged P retain their crushed shape. The protrusions 101A that are completely crushed and the protrusions 101B that are partially crushed retain their crushed shape, while the protrusions 101C in the surrounding areas that are not pressed against by the object to be packaged P maintain their original, uncrushed shape. The object to be packaged P is held (gripped) and fixed in place by the protrusions 101A that retain their crushed shape, the protrusions 101B that are partially crushed, and the protrusions 101C that maintain their original, uncrushed shape.
[0130] Furthermore, when the lid portion 130 closes the opening on the upper end surface of the container portion 110, the protrusions 121 scattered on the lid portion 130 press against the object to be packaged P from above, crushing the protrusions 121 scattered on the upper end surface 120. The protrusions 121A that are completely crushed and the protrusions 121B that are partially crushed by the object to be packaged P retain their crushed shape. The protrusions 121A that are completely crushed and the protrusions 121B that are partially crushed retain their crushed shape, while the protrusions 121C in the surrounding areas that are not pressed against by the object to be packaged P maintain their original, uncrushed shape. The object to be packaged P is held (gripped) and fixed by the protrusions 121A that retain their crushed shape, the protrusions 121B that are partially crushed, and the protrusions 121C that maintain their original, uncrushed shape, and vertical shaking is suppressed.
[0131] Figure 30 is a schematic cross-sectional view showing a packaging container formed from a single sheet, comprising a bottom portion with scattered upward-pointing protrusions, a container portion extending vertically along the outer circumference of the bottom portion, and a lid portion that closes the opening on the upper end surface of the container portion. As shown in Figure 30(A), the packaging container comprises a bottom portion 140 with scattered protrusions 141, a container portion 150, and a lid portion 160 that closes the opening on the upper end surface of the container portion 150. The lid portion 160 and the container portion 150 are connected by a hinge portion 142, and the hinge portion 142 is bent so that the lid portion 160 closes the opening on the upper end surface of the container portion 150. Figure 30(B) is a schematic cross-sectional view showing the packaging object P being pressed against the scattered protrusions 141 on the bottom portion 140 of the packaging container in Figure 30(A), and the opening on the upper end surface of the container portion 150 being closed by the lid portion 160.
[0132] As shown in Figure 30(B), by pressing the object to be packaged P against the bottom surface 140 from above along the thickness direction, the protrusions 141 scattered on the bottom surface 140 are crushed. The protrusions 141A that are completely crushed and the protrusions 141B that are partially crushed by the object to be packaged P retain their crushed shape. The object to be packaged P is held (gripped) and fixed in place by the protrusions 141A that retain their crushed shape and the protrusions 141B that are partially crushed. Furthermore, when the lid 160 closes the opening on the upper end surface of the container 150, the lid 160 presses the object to be packaged P against the protrusions 141 from above.
[0133] 4. A fourth embodiment (another example of a packaging method)
[0134] In the packaging methods of the first and second embodiments, a sheet with scattered protrusions and a container portion for containing the object to be packaged were prepared separately, and these were combined to assemble the packaging container. However, in the packaging method of this embodiment, a bottom portion with scattered upward-pointing protrusions from the sheet and a container portion extending vertically along the outer circumference of the bottom portion are formed, and a lid portion is formed from a different sheet than the sheet on which the bottom portion and container portion were formed, and these are combined to construct the packaging container. In other words, the bottom portion, container portion, and lid portion are formed separately using multiple different sheets, the object to be packaged is placed inside the container portion, and the lid portion is combined to package it.
[0135] The packaging method of this embodiment involves placing the object to be packaged in a packaging container formed from multiple sheets, which comprises a bottom portion, a container portion, and a lid portion that closes the opening on the upper end surface of the container portion. The bottom portion is formed with convex portions pointing upwards. The object to be packaged is placed in the packaging container so as to be pressed down onto the convex portions from above. When the convex portions are crushed, they maintain the shape crushed by the object to be packaged, and the object to be packaged is secured by the crushed convex portions and / or the convex portions that maintain their original, uncrushed shape. The sheet used is the same as the sheet described in the first embodiment. Therefore, a description of the sheet is omitted. The lid portion is also formed with convex portions pointing towards the bottom portion inside the packaging container. When the opening is closed, the lid portion presses the object to be packaged against the convex portions formed on the bottom portion and the convex portions formed on the lid. When the convex portions are crushed, they maintain the shape crushed by the object to be packaged, and the object to be packaged is secured by the crushed convex portions and / or the convex portions that maintain their original, uncrushed shape.
[0136] The present invention may also adopt the following configurations: [1] A packaging method comprising pressing an object to be packaged against the protrusions of a sheet having scattered protrusions, and when the protrusions are crushed, the protrusions maintain the crushed shape caused by the object to be packaged, and the object to be packaged is fixed by the crushed shape of the protrusions and / or the protrusions that maintain their original, uncrushed shape. [2] The packaging method according to [1], wherein the sheet having scattered protrusions is formed from a resin composition containing a biomass material and a thermoplastic resin. [3] The packaging method according to [1] or [2], wherein the end face of the object to be packaged opposite to the sheet side is covered with a film, and the object to be packaged is pressed against the protrusions with the film. [4] The packaging method according to [1] or [2], wherein the top and bottom of the object to be packaged are sandwiched between the sheet having scattered protrusions. [5] The packaging method according to [1] or [2], wherein the left and right sides of the object to be packaged are sandwiched between the sheet having scattered protrusions. [6] The packaging method according to [1] or [2], wherein the top, bottom, left, and right sides of the object to be packaged are sandwiched between sheets on which the protrusions are scattered. [7] The packaging method according to [1] or [2], wherein the sheet on which the protrusions are scattered is wrapped around the object to be packaged. [8] A packaging method for packaging an object to be packaged using a sheet on which protrusions are scattered, wherein the protrusions of the sheet are crushed in advance to match the shape of the object to be packaged, and the object to be packaged is placed and fixed in the crushed areas, so that the object to be packaged can be fixed by the crushed shape of the protrusions and / or the original shape of the protrusions that are not crushed. [9] A packing method for packing an object using a sheet with scattered protrusions, wherein all of the protrusions on the sheet are crushed in advance, the object to be packed is placed on the crushed protrusions, and then the back side of the crushed protrusions is pressed to match the shape of the object to be packed, thereby restoring the shape of the protrusions, and the object to be packed is secured by the crushed protrusions and / or the protrusions that maintain their original, uncrushed shape.
[10] A packaging method for arranging an object to be packaged in a packaging container having a bottom portion and a container portion, which is formed from a single sheet, wherein upwardly pointing protrusions are formed on the bottom portion, and the object to be packaged is placed in the packaging container so as to be pressed down on the protrusions from above, and when the protrusions are crushed, the protrusions maintain the shape crushed by the object to be packaged, and the object to be packaged is fixed by the crushed shape of the protrusions and / or the protrusions that maintain their original, uncrushed shape.
[11] The packaging method according to
[10] , wherein the packaging container has a lid portion that closes the opening on the upper end surface of the container portion, and when the opening is closed, the object to be packaged is pressed down on the protrusions by the lid portion.
[12] The packaging method according to
[11] , wherein the lid is formed with convex portions toward the bottom surface, and when the opening is closed, the lid presses the object to be packaged against the convex portions formed on the bottom surface and the convex portions formed on the lid, and when the convex portions are crushed, the convex portions maintain the shape crushed by the object to be packaged, and the object to be packaged is fixed by the crushed shape of the convex portions and / or the convex portions that maintain their original, uncrushed shape.
[13] A packaging method for arranging an object to be packaged in a packaging container having a bottom portion, a container portion, and a lid portion that closes the opening on the upper end surface of the container portion, wherein the bottom portion is formed to have upwardly pointing protrusions scattered thereon, the object to be packaged is placed in the packaging container so as to be pressed down onto the protrusions from above, and when the protrusions are crushed, the protrusions maintain the shape crushed by the object to be packaged, and the object to be packaged is fixed by the crushed shape of the protrusions and / or the protrusions that maintain their original, uncrushed shape.
[14] The packaging method according to
[13] , wherein the lid is formed with convex portions toward the bottom surface, and when the opening is closed, the lid presses the object to be packaged against the convex portions formed on the bottom surface and the convex portions formed on the lid, and when the convex portions are crushed, the convex portions maintain the shape crushed by the object to be packaged, and the object to be packaged is fixed by the crushed shape of the convex portions and / or the convex portions that maintain their original, uncrushed shape.
[15] The packaging method according to any one of [1] to
[13] , wherein the object to be packaged is fixed manually.
[16] The packaging method according to any one of [1] to
[13] , wherein the object to be packaged is fixed automatically.
[0137] The configurations, methods, processes, shapes, materials, and numerical values listed in the above embodiments are merely examples, and different configurations, methods, processes, shapes, materials, and numerical values may be used as needed.
[0138] Furthermore, the configurations, methods, processes, shapes, materials, and numerical values of the above-described embodiments and examples can be combined with each other, as long as they do not depart from the spirit of these embodiments.
[0139] Furthermore, in this specification, numerical ranges indicated using "~" represent a range that includes the numerical values before and after "~" as the minimum and maximum values, respectively. In numerical ranges described stepwise in this specification, the upper or lower limit of a numerical range in one step may be replaced with the upper or lower limit of a numerical range in another step. Unless otherwise specified, the materials exemplified in this specification can be used individually or in combination of two or more.
[0140] 1. Convex part 10. Sheet 40. Sheet 41. Convex part 50. Sheet 51. Convex part 51f. First convex part 51s. Second convex part 60. Sheet 61. Convex part 61f. First convex part 61s. Second convex part 61t. Third convex part
Claims
1. A packaging method comprising pressing an object to be packaged against the protrusions of a sheet having scattered protrusions, and when the protrusions are crushed, the protrusions maintain the shape crushed by the object to be packaged, thereby securing the object to be packaged by the crushed shape of the protrusions and / or the protrusions that maintain their original, uncrushed shape.
2. The packaging method according to claim 1, wherein the sheet on which the protrusions are scattered is formed from a resin composition containing a biomass material and a thermoplastic resin.
3. The packaging method according to claim 1, wherein the end face of the object to be packaged, opposite to the sheet side, is covered with a film, and the object to be packaged is pressed against the protrusion with the film.
4. The packaging method according to claim 1, wherein the object to be packaged is sandwiched between sheets on which the protrusions are scattered.
5. The packaging method according to claim 1, wherein the left and right sides of the object to be packaged are sandwiched between sheets on which the protrusions are scattered.
6. The packaging method according to claim 1, wherein the top, bottom, left, and right sides of the object to be packaged are sandwiched between sheets on which the protrusions are scattered.
7. The packaging method according to claim 1, wherein the sheet on which the protrusions are scattered is wrapped around the object to be packaged.
8. A packaging method for packaging an object to be packaged using a sheet with scattered protrusions, wherein the protrusions of the sheet are pre-flattened to match the shape of the object to be packaged, and the object to be packaged is placed and fixed in the flattened areas, so that the object to be packaged can be fixed by the flattened shape of the protrusions and / or the protrusions that maintain their original, unflattened shape.
9. A packaging method for packaging an object using a sheet with scattered protrusions, wherein all of the protrusions on the sheet are crushed in advance, the object to be packaged is placed on the crushed protrusions, and then the back side of the crushed protrusions is pressed to match the shape of the object to be packaged, thereby restoring the shape of the protrusions, and the object to be packaged is secured by the crushed protrusions and / or the protrusions that maintain their original, uncrushed shape.
10. A packaging method for arranging an object to be packaged in a packaging container having a bottom portion and a container portion, which is formed by molding from a single sheet, wherein upwardly pointing protrusions are formed on the bottom portion, the object to be packaged is placed in the packaging container so as to be pressed down onto the protrusions from above, and when the protrusions are crushed, the protrusions maintain the shape crushed by the object to be packaged, and the object to be packaged is fixed in place by the crushed shape of the protrusions and / or the protrusions that maintain their original, uncrushed shape.
11. The packaging method according to claim 10, wherein the packaging container is provided with a lid that closes the opening on the upper end surface of the container portion, and when the opening is closed, the lid presses the object to be packaged against the protrusion.
12. The packaging method according to claim 11, wherein the lid portion is formed with convex portions extending toward the bottom portion, and when the opening is closed, the lid portion presses the object to be packaged against the convex portions formed on the bottom portion and the convex portions formed on the lid portion, and when the convex portions are crushed, the convex portions maintain the shape crushed by the object to be packaged, and the object to be packaged is fixed by the crushed shape of the convex portions and / or the convex portions that maintain their original, uncrushed shape.
13. A packaging method for arranging an object to be packaged in a packaging container, which is formed from multiple sheets and comprises a bottom portion, a container portion, and a lid portion that closes the opening on the upper end surface of the container portion, wherein the bottom portion is formed with upwardly pointing protrusions scattered thereon, the object to be packaged is placed in the packaging container so as to be pressed down onto the protrusions from above, and when the protrusions are crushed, the protrusions maintain the shape crushed by the object to be packaged, and the object to be packaged is fixed in place by the crushed shape of the protrusions and / or the protrusions that maintain their original, uncrushed shape.
14. The packaging method according to claim 13, wherein the lid is formed with convex portions extending toward the bottom surface, and when the opening is closed, the lid presses the object to be packaged against the convex portions formed on the bottom surface and the convex portions formed on the lid, and when the convex portions are crushed, the convex portions maintain the shape crushed by the object to be packaged, and the object to be packaged is fixed by the crushed shape of the convex portions and / or the convex portions that maintain their original, uncrushed shape.
15. The packaging method according to claim 1, wherein the object to be packaged is fixed manually.
16. The packaging method according to claim 1, wherein the packaging method is further characterized in that the packaging object is automatically secured.