ADHESIVE-FREE PACKAGING STRUCTURE

Abstract

An adhesive-free packaging structure includes a substrate, at least one foldable area, and at least one first connecting structure. The substrate includes a first end portion and a second end portion, and a material of the substrate includes a natural fiber. The foldable area is disposed on the substrate and includes at least one folding line. The first connecting structure is disposed on the substrate and includes a first connecting element and a second connecting element respectively disposed on the first end portion and the second end portion. When the substrate is bent along the foldable area, the first end portion and the second end portion approach each other and the first connecting element and the second connecting element are correspondingly assembled.

Claims

1. An adhesive-free packaging structure, comprising: a substrate comprising a first end portion and a second end portion, wherein a material of the substrate comprises a natural fiber; at least one foldable area disposed on the substrate and comprising at least one folding line; and at least one first connecting structure disposed on the substrate and comprising a first connecting element and a second connecting element, wherein the first connecting element and the second connecting element are respectively disposed on the first end portion and the second end portion; wherein, when the substrate is bent along the foldable area, the first end portion and the second end portion approach each other, so the first connecting element and the second connecting element are correspondingly assembled.

2. The adhesive-free packaging structure of claim 1, wherein a connecting length of the first connecting structure is more than 50% of a length of the first end portion.

3. The adhesive-free packaging structure of claim 1, wherein a connecting length of the first connecting structure is more than 80% of a length of the first end portion.

4. The adhesive-free packaging structure of claim 3, wherein a weight percentage of the natural fiber in the substrate is greater than or equal to 50%.

5. The adhesive-free packaging structure of claim 1, wherein the material of the substrate is a non-plastic material.

6. The adhesive-free packaging structure of claim 1, wherein a thickness of the substrate is T, and the following condition is satisfied:
50 ?m?T?500 ?m.

7. The adhesive-free packaging structure of claim 1, wherein the first connecting element is a slot, the second connecting element is an insertion member, and the second connecting element is correspondingly inserted to the first connecting element.

8. The adhesive-free packaging structure of claim 1, wherein the substrate comprises a body, a first side board, a second side board, a third side board, and a fourth side board, and the first side board, the second side board, the third side board, and the fourth side board are respectively connected to four sides of the body; wherein the first end portion is disposed on one side of the first side board away from the body, and the second end portion is disposed on one side of the second side board away from the body.

9. The adhesive-free packaging structure of claim 8, wherein: a number of the at least one foldable area is four, and the four foldable areas are respectively disposed between the body and the first side board, between the body and the second side board, between the body and the third side board, and between the body and the fourth side board; and when the first side board, the second side board, the third side board, and the fourth side board are respectively bent along the four foldable areas toward the body, the first side board, the second side board, the third side board, and the fourth side board approach each other so as to form an accommodating space by folding the adhesive-free packaging structure.

10. An adhesive-free packaging structure comprising: a substrate, comprising: a body having two body sides and comprising a first extending portion and a second extending portion, the first extending portion having a first end portion, and the second extending portion having a second end portion; and two side boards respectively connected to the two body sides, wherein each of the two side boards comprises a first connecting side, a second connecting side, and an open connecting side, and the open connecting side of each of the two side boards is not connected to the two body sides; wherein a material of the substrate comprises a natural fiber; at least two foldable areas disposed on the substrate and respectively located between the two side boards and the body, wherein each of the two foldable areas comprises at least one folding line; a first connecting structure disposed on the substrate and comprising a first connecting element and a second connecting element, wherein the first connecting element is connected to the open connecting side of one of the two side boards, and the second connecting element is connected to the open connecting side of another one of the two side boards; and at least two second connecting structures disposed on the substrate, each of the at least two second connecting structures comprising at least one third connecting element and at least one fourth connecting element, wherein the at least one third connecting element of one of the at least two second connecting structures is disposed on the first end portion, the at least one fourth connecting element of the one of the at least two second connecting structures is connected to the first connecting side of one of the two side boards, the at least one third connecting element of another one of the at least two second connecting structures is disposed on the second end portion, and the at least one fourth connecting element of the another one of the at least two second connecting structures is connected to the second connecting side of the one of the two side boards; wherein, when the two side boards are respectively bent along the at least two foldable areas, the open connecting side of the one of the two side boards and the open connecting side of the another one of the two side boards approach each other, so the first connecting element and the second connecting element are correspondingly assembled; and wherein, when the two side boards are respectively bent along the at least two foldable areas, the first connecting side of the one of the two side boards and the first end portion approach each other, and the second connecting side of the one of the two side boards and the second end portion approach each other, so the two third connecting elements of the at least two second connecting structures are respectively and correspondingly assembled to the two fourth connecting elements of the at least two second connecting structures.

11. The adhesive-free packaging structure of claim 10, wherein a connecting length of the first connecting structure is more than 50% of a length of the open connecting side of each of the two side boards.

12. The adhesive-free packaging structure of claim 10, wherein a connecting length of each of the two second connecting structures is more than 50% of a length of the first end portion, the connecting length of each of the two second connecting structures is more than 50% of a length of the second end portion, the connecting length of each of the two second connecting structures is more than 50% of a length of the first connecting side of each of the two side boards, and the connecting length of each of the two second connecting structures is more than 50% of a length of the second connecting side of each of the two side boards.

13. The adhesive-free packaging structure of claim 10, wherein a weight percentage of the natural fiber in the substrate is greater than or equal to 50%.

14. The adhesive-free packaging structure of claim 10, wherein the material of the substrate is a non-plastic material.

15. The adhesive-free packaging structure of claim 10, wherein a thickness of the substrate is T, and the following condition is satisfied:
50 ?m?T?500 ?m.

16. The adhesive-free packaging structure of claim 10, wherein the first connecting element is a slot, the second connecting element is an insertion member, and the second connecting element is correspondingly inserted to the first connecting element.

17. The adhesive-free packaging structure of claim 10, wherein each of the at least one third connecting element is a slot, each of the at least one fourth connecting element is an insertion member, and each of the at least one fourth connecting element is correspondingly inserted to one of the at least one third connecting element.

18. The adhesive-free packaging structure of claim 10, wherein: each of the at least two second connecting structures comprises at least two fourth connecting elements, another one of the two fourth connecting elements of the one of the at least two second connecting structures is connected to the first connecting side of the another one of the two side boards, and another one of the two fourth connecting elements of the another one of the at least two connecting structures is connected to the second connecting side of the another one of the two side boards; and when the two side boards are bent respectively along the two foldable areas, the first connecting side of the another one of the two side boards and the first end portion approach each other, and the second connecting side of the another one of the two side boards and the second end portion approach each other, so the two third connecting elements of the at least two second connecting structures are respectively correspondingly assembled to the two fourth connecting elements of each of the two second connecting structures.

19. The adhesive-free packaging structure of claim 18, wherein a number of the at least one folding line of each of the two foldable areas is at least two.

20. The adhesive-free packaging structure of claim 10, wherein the body is rectangular-shaped.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The present disclosure can be more fully understood by reading the following detailed description of the embodiment, with reference made to the accompanying drawings as follows:

[0009] FIG. 1 is a schematic view of an adhesive-free packaging structure according to one embodiment of the present disclosure.

[0010] FIG. 2A is a schematic view of the adhesive-free packaging structure of FIG. 1 being folded.

[0011] FIG. 2B is another schematic view of the adhesive-free packaging structure of FIG. 1 being folded.

[0012] FIG. 3 is a schematic view of an adhesive-free packaging structure according to another embodiment of the present disclosure.

[0013] FIG. 4A is a schematic view of the adhesive-free packaging structure of FIG. 3 being folded.

[0014] FIG. 4B is a partial schematic view of the adhesive-free packaging structure of FIG. 3 being folded.

[0015] FIG. 4C is another partial schematic view of the adhesive-free packaging structure of FIG. 3 being folded.

DETAILED DESCRIPTION

[0016] The present disclosure is more particularly described in the following examples that are intended as illustrative only since numerous modifications and variations therein will be apparent to those skilled in the art. Like numbers in the drawings indicate like components throughout the views. As used in the description herein and throughout the claims that follow, unless the context clearly dictates otherwise, the meaning of a, an, and the includes plural reference, and the meaning of in includes in and on. Titles or subtitles can be used herein for the convenience of a reader, which shall have no influence on the scope of the present disclosure.

[0017] The terms used herein generally have their ordinary meanings in the art. In the case of conflict, the present document, including any definitions given herein, will prevail. The same thing can be expressed in more than one way. Alternative language and synonyms can be used for any term(s) discussed herein, and no special significance is to be placed upon whether a term is elaborated or discussed herein. A recital of one or more synonyms does not exclude the use of other synonyms. The use of examples anywhere in this specification including examples of any terms is illustrative only, and in no way limits the scope and meaning of the present disclosure or of any exemplified term. Likewise, the present disclosure is not limited to various embodiments given herein. Numbering terms such as first, second or third can be used to describe various components, signals or the like, which are for distinguishing one component/signal from another one only, and are not intended to, nor should be construed to impose any substantive limitations on the components, signals or the like.

[0018] FIG. 1 is a schematic view of an adhesive-free packaging structure 100 according to one embodiment of the present disclosure. Referring to FIG. 1, the adhesive-free packaging structure 100 includes a substrate 110, at least one foldable area 130, and at least one first connecting structure 140.

[0019] The substrate 110 includes a first end portion 111 and a second end portion 112. Specifically, in the adhesive-free packaging structure 100 shown in FIG. 1, the substrate 110 can include a body 121, a first side board 122, a second side board 123, a third side board 124, and a fourth side board 125. The first side board 122, the second side board 123, the third side board 124, and the fourth side board 125 are respectively connected to four sides (reference number is omitted) of the body 121. The first end portion 111 can be disposed on one side of the first side board 122 away from the body 121, and the second end portion 112 can be disposed on the side of the second side board 123 away from the body 121.

[0020] A material of the substrate 110 can include a natural fiber and can be a non-plastic material. The natural fiber can be natural materials such as cellulose and lignin, and a weight percentage of the natural fiber in the substrate 110 is greater than or equal to 50%. Therefore, without affecting the packaging effect, the adhesive-free packaging structure 100 of the present disclosure uses natural fiber materials to replace traditional plastic bags, plastic non-woven films and other packaging materials, so that it can not only effectively reduce the using amount of the plastic materials, but also conform to the current society's demands for environmental protection.

[0021] Moreover, in the adhesive-free packaging structure 100, a thickness of the substrate 110 of the adhesive-free packaging structure 100 is T, and the following condition can be satisfied: 50 ?m? T? 500 ?m. Therefore, the packaging material specification requirements of different products can be satisfied, and the application potential of the adhesive-free packaging structure 100 in related industries can be enhanced.

[0022] The foldable area 130 is disposed on the substrate 110 and includes at least one folding line 131. In specific, a number of the at least one foldable area 130 of the adhesive-free packaging structure 100 in FIG. 1 can be four, and the four foldable areas 130 are respectively disposed between the body 121 and the first side board 122, between the body 121 and the second side board 123, between the body 121 and the third side board 124, and between the body 121 and the fourth side board 125. When the first side board 122, the second side board 123, the third side board 124, and the fourth side board 125 are respectively bent along the four foldable areas 130 toward the body 121, the first side board 122, the second side board 123, the third side board 124, and the fourth side board 125 approach each other so as to form an accommodating space (not shown) by folding the adhesive-free packaging structure 100. The accommodating space is for containing items and goods, which makes the use of the adhesive-free packaging structure 100 more convenient.

[0023] Further, the folding line 131 is any line defining a hinge line in the substrate 110, which is used to facilitate the folding of a portion of the substrate 110 or the body 121, the first side board 122, the second side board 123, the third side board 124 and the fourth side board 125 relative to each other, or otherwise indicates the optimal folding position on the substrate 110. Furthermore, the folding line 131 can be formed by a single indentation, a single half-cut line, a punch line, a cutting line, a short slit line, a half-cut line, an indentation line, etc., and any combination thereof, and the present disclosure is not limited thereto.

[0024] The first connecting structure 140 is disposed on the substrate 110 and includes a first connecting element 141 and a second connecting element 142. The first connecting element 141 and the second connecting element 142 are respectively disposed on the first end portion 111 and the second end portion 112. In particular, the first connecting element 141 can be a slot, the second connecting element 142 can be an insertion member, and the second connecting element 142 is correspondingly inserted to the first connecting element 141 to enhance the easy assembly of the adhesive-free packaging structure 100. Furthermore, the slot shape of the first connecting element 141 and the insertion member shape of the second connecting element 142 can be configured into different shapes according to requirements. However, the shapes of the first connecting element 141 and the second connecting element 142 need to match each other so as to ensure that the first connecting element 141 and the second connecting element 142 are constrained by each other through buckling manner. Thus, the first connecting structure 140 of the present disclosure is securely fixed and does not become loose easily, and the present disclosure is not limited to the shape disclosed in the drawings. Therefore, the cost of using conventional adhesives to adhere packaging materials can be eliminated under the premise of high fixation effects, and the environmental pollution caused by adhesives can be effectively reduced.

[0025] A connecting length LC1 (labeled in FIG. 2B) of the first connecting structure 140 can be more than 50% of the length LS1 (labeled in FIG. 2B) of the first end portion 111, and the connecting length LC1 of the first connecting structure 140 can be more than 50% of the length LS2 (labeled in FIG. 2B) of the second end portion 112. Thus, it is favorable for preventing the connection strength of the first connecting structure 140 from being affected by the warping of the portion of the first connecting structure 140 that is not constrained when the first connecting structure 140 is used to fix the first end portion 111 and the second end portion 112 of the substrate 110. More particularly, the connecting length LC1 of the first connecting structure 140 is the total length of the portion where the first connecting element 141 and the second connecting element 142 are correspondingly assembled and constrained to each other. The length of the first connecting element 141 can be more than 50% of the length LS1 of the first end portion 111 or more than 50% of the length LS2 of the second end portion 112, or the length of the second connecting element 142 can be more than 50% of the length LS1 of the first end portion 111 or more than 50% of the length LS2 of the second end portion 112. Further, both the length of the first connecting element 141 and the length of the second connecting element 142 can be more than 50% of the length LS1 of the first end portion 111 or more than 50% of the length LS2 of the second end portion 112, but the present disclosure is not limited thereby. Further, the connecting length LC1 of the first connecting structure 140 can be more than 80% of the length LS1 of the first end portion 111 or more than 80% of the length LS2 of the second end portion 112 so as to further enhance the constrain strength between the first connecting element 141 and the second connecting element 142.

[0026] FIG. 2A is a schematic view of the adhesive-free packaging structure 100 of FIG. 1 being folded, and FIG. 2B is another schematic view of the adhesive-free packaging structure 100 of FIG. 1 being folded. FIG. 1, FIG. 2A, and FIG. 2B will be referenced when describing the usage and details of the adhesive-free packaging structure 100 of the present disclosure.

[0027] As shown in FIG. 1 and FIG. 2A, when an item or goods are wrapped with the adhesive-free packaging structure 100, the third side board 124 and the fourth side board 125 are respectively bent first along the folding lines 131 of the two foldable areas 130 and then approach each other, so that the third side board 124 and the fourth side board 125 will stack on top of one another. Then, the first side board 122 and the second side board 123 are respectively bent along the folding lines 131 of the two foldable areas 130, so that the first end portion 111 and the second end portion 112 will approach each other, and thus the first connecting element 141 and the second connecting element 142 are correspondingly assembled.

[0028] Referring to FIG. 2B, after the first connecting element 141 and the second connecting element 142 are assembled, the second connecting element 142 being the insertion member is inserted to the first connecting element 141 being the slot so as to firmly connect the first end portion 111 and the second end portion 112. Therefore, the adhesive-free packaging structure 100 of the present disclosure is folded to form an accommodating space (reference is omitted) for containing an item therein, thereby achieving the goal of packaging the item stably and securely as well as providing buffer or cushioning to the contained item.

[0029] Therefore, by correspondingly assembling the first connecting element 141 and the second connecting element 142 of the first connecting structure 140, the adhesive-free packaging structure 100 of the present disclosure is able to be fixed without using any adhesive, and the assembly convenience can be effectively enhanced. Further, the connection strength of the first connecting structure 140 can be greatly enhanced by arranging the connecting length LC1 of the first connecting structure 140 to be more than 50% of the length LS1 of the first end portion 111 or more than 50% of the length LS2 of the second end portion 112, and thus the overall packaging efficiency of the adhesive-free packaging structure 100 can be increased. Furthermore, by the arrangement that the material of the substrate 110 includes natural fibers and is a non-plastic material, the adhesive-free packaging structure 100 of the present disclosure can effectively reduce the using amount of plastic materials. Thus, it is friendlier to the environment, and there is more plastic reduction compared to the existing products, and has potential in the applications in related industries.

[0030] FIG. 3 is a schematic view of an adhesive-free packaging structure 200 according to another embodiment of the present disclosure. Referring to FIG. 3, the adhesive-free packaging structure 200 includes a substrate 210, at least two foldable areas 240, a first connecting structure 250 (labeled in FIG. 4A), and at least two second connecting structures 260 (labeled in FIG. 4A).

[0031] The substrate 210 includes a body 220, a side board 230a and a side board 230b. The body 220 has two body sides 221 and includes a first extending portion 222 and a second extending portion 223. The first extending portion 222 has a first end portion 224, and the second extending portion 223 has a second end portion 225. The side board 230a and the side board 230b are respectively connected to the two body sides 221. The side board 230a includes a first connecting side 231a, a second connecting side 232a, and an open connecting side 233a, and the side board 230b includes a first connecting side 231b, a second connecting side 232b, and an open connecting side 233b. The open connecting side 233a of the side board 230a and the open connecting side 233b of the side board 230b are not connected to the two body sides 221. Specifically, the shape of the body 220 can be rectangular, and the first extending portion 222 and the second extending portion 223 are regions that extend respectively toward two opposite ends of the body 220. The first end portion 224 and the second end portion 225 are respectively disposed on the side of the first extending portion 222 away from the body 220 and the side of the second extending portion 223 away from the body 220. Thus, it is favorable for the subsequent assembly, but the present disclosure is not limited thereby.

[0032] A material of the substrate 210 is similar to that of the substrate 110 of the adhesive-free packaging structure 100 in FIG. 1, and the material is a non-plastic material and can include a natural fiber. Further, the thickness of the substrate 210 is also similar to that of the substrate 110 of FIG. 1 and thus will not be described herein.

[0033] The two foldable areas 240 are disposed on the substrate 210 and respectively located between the side board 230a and the body 220 and between the side board 230b and the body 220, and each foldable area 240 includes at least one folding line 241. Each of the foldable areas 240 of the adhesive-free packaging structure 200 shown in FIG. 3 includes at least two folding lines 241 (in FIG. 3, only one of the folding line 241 of each of the foldable areas 240 is labeled). Take the body 220 and the side board 230a as an example, one of the folding lines 241 of the foldable area 240 can be disposed between the body 220 and the side board 230a, and the other one of the folding lines 241 is arranged to be overlapped with one of the body sides 221. In other words, the other one of the folding lines 241 is formed on one of the body sides 221 for folding the side board 230a relative to the body 220. Further, the folding line 241 can be formed by a single indentation, a single half-cut line, a punch line, a cutting line, a short slit line, a half-cut line, an indentation line, etc., and any combination thereof, for indicating the optimal folding position on the substrate 210, and the present disclosure is not limited thereto.

[0034] The first connecting structure 250 is disposed on the substrate 210 and includes a first connecting element 251 and a second connecting element 252. The first connecting element 251 is connected to the open connecting side 233a of the side board 230a, and the second connecting element 252 is connected to the open connecting side 233b of the side board 230b.

[0035] The two second connecting structures 260 are disposed on the substrate 210, and each of the two second connecting structures 260 includes at least one third connecting element 261 and at least one fourth connecting element 262. The third connecting element 261 of one of the two second connecting structures 260 is disposed on the first end portion 224, and the fourth connecting element 262 of the one of the two second connecting structures 260 is connected to the first connecting side 231a of the side board 230a. The third connecting element 261 of the other one of the two second connecting structures 260 is disposed on the second end portion 225, and the fourth connecting element 262 of the other one of the two second connecting structures 260 is connected to the second connecting side 232a of the side board 230a.

[0036] When the side board 230a and the side board 230b are respectively bent along the two foldable areas 240, and the open connecting side 233a of the side board 230a and the open connecting side 233b of the side board 230b approach each other, the first connecting element 251 and the second connecting element 252 are correspondingly assembled. Similarly, the first connecting side 231a of the side board 230a and the first end portion 224 approach each other, and the second connecting side 232a of the side board 230a and the second end portion 225 approach each other, so the two third connecting elements 261 are respectively assembled with the two fourth connecting elements 262.

[0037] Therefore, the goal of fixing the adhesive-free packaging structure 200 can be achieved without using any adhesive, and the assembly convenience of the adhesive-free packaging structure 200 can be improved.

[0038] More particularly, in the adhesive-free packaging structure 200 of FIG. 3, each of the second connecting structures 260 can include at least two fourth connecting elements 262. The other one of the fourth connecting elements 262 of the one of the second connecting structures 260 is connected to the first connecting side 231b of the side board 230b, and the other one of the fourth connecting elements 262 of the other one of the second connecting structures 260 is connected to the second connecting side 232b of the side board 230b. When side board 230a and the side board 230b are respectively bent along the two foldable areas 240, the first connecting side 231b of the side board 230b and the first end portion 224 approach each other, and the second connecting side 232b of the side board 230b and the second end portion 225 approach each other, so the two third connecting elements 261 are respectively assembled to the two fourth connecting elements 262 of each of the second connecting structures 260. Therefore, the overall structural strength of the adhesive-free packaging structure 200 after being assembled can be enhanced, and it is favorable for increasing the margin of adhesive-free packaging structure 200 so as to meet the packaging needs of different items. Further, as shown in FIG. 3, each of the fourth connecting elements 262 can include two fourth connecting members 263, so that it is favorable for enhancing the overall structural tightness of the adhesive-free packaging structure 200 after being assembled, and the present disclosure is not limited thereby.

[0039] Further, the first connecting element 251 can be a slot, the second connecting element 252 can be an insertion member, and the second connecting element 252 can be correspondingly inserted to the first connecting element 251. Each of the third connecting elements 261 can be a slot, each of the fourth connecting elements 262 can be an insertion member, and each of the fourth connecting elements 262 can be correspondingly inserted to one of the third connecting elements 261. Therefore, the overall structural strength of the adhesive-free packaging structure 200 after being assembled can be enhanced, and the assembly convenience thereof also can be improved. Furthermore, the slot shape of the first connecting element 251 and the third connecting elements 261 as well as the insertion member shape of the second connecting element 252 and the fourth connecting elements 262 can be configured into different shapes according to requirements. However, the shapes of the first connecting element 251 and the second connecting element 252 need to match each other, and the shapes of the third connecting element 261 and the fourth connecting element 262 need to match each other, so that the constrained condition there between through buckling manner can be ensured, and the present disclosure is not limited to the shape disclosed in the drawings.

[0040] FIG. 4A is a schematic view of the adhesive-free packaging structure 200 of FIG. 3 being folded, FIG. 4B is a partial schematic view of the adhesive-free packaging structure 200 of FIG. 3 being folded, and FIG. 4C is another partial schematic view of the adhesive-free packaging structure 200 of FIG. 3 being folded. FIG. 3 and FIG. 4A to FIG. 4C will be referenced during the description of the usage and the details of the adhesive-free packaging structure 200 according to the present disclosure.

[0041] As shown in FIG. 3 and FIG. 4A, a connecting length LC1 of the first connecting structure 250 can be more than 50% of a length L1a of the open connecting side 233a and more than 50% of a length L2b of the open connecting side 233b, and the connecting length LC1 of the first connecting structure 250 is the total length of the portions of the first connecting element 251 and the second connecting element 252 that are in constraint after correspondingly assembled. Thus, it is favorable for preventing the connection strength of the first connecting structure 250 from being affected by the warping of the portion of the first connecting structure 250 that is not constrained when the first connecting structure 250 is used to fix the side board 230a and the side board 230b. Further, in FIG. 4A, after the first connecting element 251 and the second connecting element 252 are correspondingly assembled, the first connecting structure 250 can have an arrangement of three sheets with arched edges overlapping and constraining one another, and the connecting length LC1 of the first connecting structure 250 is 100% of the length L1a of the open connecting side 233a and the length L1b of the open connecting side 233b, which can greatly enhance the connection strength of the first connecting structure 250.

[0042] As shown in FIG. 3 and FIG. 4C, the connecting length LC2 of each of the second connecting structures 260 is more than 50% of the length LS1 of the first end portion 224. The connecting length LC2 of each of the second connecting structures 260 is more than 50% of the length LS2 of the second end portion 225. The connecting length LC2 of each of the second connecting structures 260 is more than 50% of the length L2a of the first connecting side 231a and the length L2b of the first connecting side 231b. The connecting length LC2 of each of the second connecting structures 260 can be more than 50% of the length L3a of the second connecting side 232a and the length L3b of the second connecting side 232b. The connecting structure LC2 of the second connecting structure 260 is the total length of the constraining portion where the third connecting element 261 and the fourth connecting element 262 are assembled. Hence, the connection strength of the second connecting structure 260 can be enhanced.

[0043] Referring to FIG. 3 and FIG. 4A, when an item is wrapped with the adhesive-free packaging structure 200, the side board 230a and the side board 230b are respectively bent along the two foldable areas 240 first, and the open connecting side 233a of the side board 230a and the open connecting side 233b of the side board 230b approach each other, so that the second connecting element 252 being an insertion member can be correspondingly assembled with the first connecting element 251 being a slot for stably connecting the side board 230a and the side board 230b.

[0044] Referring to FIG. 3 and FIG. 4A to FIG. 4C, when the side board 230a is connected to the side board 230b, the first connecting side 231a of the side board 230a and the first end portion 224 approach each other, and the first connecting side 231b of the side board 230b and the first end portion 224 approach each other, so that the third connecting element 261 disposed on the first end portion 224 can be respectively assembled with the fourth connecting element 262 disposed on the first connecting side 231a and the fourth connecting element 262 disposed on the first connecting side 231b. At the same time, the second connecting side 232a of the side board 230a and the second end portion 225 approach each other, and the second connecting side 232b of the side board 230b and the second end portion 225 approach each other, so that the third connecting element 261 disposed on the second side portion 225 is assembled respectively with the fourth connecting element 262 disposed on the second connecting side 232a and the fourth connecting element 262 disposed on the second connecting side 232b. Hence, the adhesive-free packaging structure 200 forms an accommodating space (reference number is omitted) for containing the item therein and achieves the effect of stably packaging an item.

[0045] Therefore, by correspondingly assembling the first connecting element 251 and the second connecting element 252, and respectively assembling the two third connecting elements 261 and the two fourth connecting elements 262, the first connecting structure 250 can be used to connect to the side board 230a and the side board 230b, and the two second connecting structures 260 can be used to further connect to the body 220, the side board 230a and the side board 230b. Therefore, the adhesive-free packaging structure 200 can be fixed without using any adhesive. Further, the connection strength of the first connecting structure 250 can be greatly enhanced by arranging the connecting length LC1 of the first connecting structure 250 to be more than 50% of the length L1a of the open connecting side 233a and the length L1b of the open connecting side 233b. Further, the overall packaging efficiency of the adhesive-free packaging structure 200 can be improved by arranging the connecting length LC2 of the second connecting structure 260 to be more than 50% of the length LS1 of the first end portion 224, more than 50% of the length LS2 of the second end portion 225, more than 50% of the length L2a of the first connecting side 231a, more than 50% of the length L2b of the first connecting side 231b, more than 50% of the length L3a of the second connecting side 232a, and more than 50% of the length L3b of the second connecting side 232b. Furthermore, with the material of the substrate 210 including natural fibers and being a non-plastic material, the adhesive-free packaging structure 200 can effectively reduce the usage of plastic materials, it is friendlier to the environment, and there is more plastic reduction compared to the existing products, and has potential in the applications in related industries.

[0046] The foregoing description of the exemplary embodiments of the disclosure has been presented only for the purposes of illustration and description and is not intended to be exhaustive or to limit the disclosure to the precise forms disclosed. Many modifications and variations are possible in light of the above teaching.

[0047] The embodiments were chosen and described in order to explain the principles of the disclosure and their practical application so as to enable others skilled in the art to utilize the disclosure and various embodiments and with various modifications as are suited to the particular use contemplated. Alternative embodiments will become apparent to those skilled in the art to which the present disclosure pertains without departing from its spirit and scope.