GB2589397A

GB2589397A - Pulp-Molded packaging article

Info

Publication number: GB2589397A
Application number: GB2008440.6A
Authority: GB
Inventors: Kuo Chien-Kuan; Huang Chun-Huang
Original assignee: Golden Arrow Printing Technology Kunshan Co Ltd
Current assignee: Golden Arrow Printing Technology Kunshan Co Ltd
Priority date: 2019-11-27
Filing date: 2020-06-04
Publication date: 2021-06-02
Also published as: US20210155360A1; FR3103468B3; GB202008440D0; FR3103468A3; CN211224329U

Abstract

A pulp-moulded packaging article 1 comprising a bottom wall 10, a top opening 26 and a standing lateral wall 20, defining an accommodation space 30, the wall 20 having a bulge region 22 and a groove region 26 at an upper end. A transversely cross-sectional thickness located at the bulge region is larger than a transversely cross-sectional thickness located at the groove region, wherein the bulge region is formed with a convex surface which protrudes inwards toward the accommodation space 30 and the groove region is formed with a concave surface away from the accommodation space 30. The bulge 22 and groove 26 define a lip that allows an object to be secured within the accommodation space 30 by snapping over the object.

Description

PULP-MOLDED PACKAGING ARTICLE

FIELD OF THE INVENTION

[0001] The present invention relates to a pulp-molded packaging article applied in a technical field of packaging materials, and in particular, a pulp-molded packaging article manufactured by a wet fiber pulp-molding process.

BACKGROUND OF THE INVENTION

[0002] In the most of the fabrications for conventional paper-made boxes, primarily a large-size two-dimensional planar cardboard are divided into a number of side-by-side interconnected and/or separated small-size two-dimensional planar cardboards. Essentially, those small-size two-dimensional planar cardboards are rendered with different and/or same geometrical shapes, such as rectangles, squares, circles and so forth. Next, each two of the small-size two-dimensional planar cardboards integrally interconnected by a side edge thereof are manually folded positive or negative 90 degrees against each other along the side edge (i.e. a lower box body having a bottom with four side edges integrally interconnected with four standing sidewalls, respectively), and/or cut-apart side edges between each two of the small-size two-dimensional planar cardboards are firmly jointed against each other (i.e. a cover body having four standing sidewalls where their adjacent side edges are jointed against each other). By the above procedure, a paper-made box can be assembled eventually in a three-dimensional structure. For example, Chinese utility model patent numbers CN204624080U and CN206750590U promptly brought forth solutions for the afore-mentioned paper-made box.

[0003] Furthermore, there were a number of conventional paper-made boxes such as a Chinese invention patent publication number CN104386330A which promptly reveals a forming process for a pulp-molded packaging article and its foldable lined structure packaged therein, wherein a solution is provided that primarily by a wet-fiber pulp-molding process, a semi-finished product of a pulp-molded packaging article having a three-dimensional structure is manufactured; next, by performing the same steps for a number of respective planar side edges of the semi-finished product, which include die-cutting for the side edges and then manually folding the die-cut side edges, the side edges are formed in reverse-fold shapes for fixedly bracing an object packaged therebetween.

[0004] Nevertheless, for all of the afore-mentioned conventional paper-made boxes, it is necessary to crop the cardboard to have a number of side edges for later on jointing together with each other; and also, it is necessary to manually fold the side edges on their integrally-connected positions so as to form respectively standing sidewalls for further assembling the paper-made box in manual, thereby resulting in laboriousness and a large of time consumption. Besides, regardless of boring through and trimming off any one of the sidewalls for shaping, it is apt to make each of the cropped side edges incurring a stress concentration phenomenon, and also it is apt to damage a structural strength or seal tightness of the whole paper-made box. Furthermore, the conventional paper-made boxes disclosed in these Chinese utility model patent numbers CN204624080U and CN206750590U can almost not provide a cushioning protection effect for objects respectively packaged therein. Although a Chinese invention patent publication number CN104386330A discloses a pulp-molded packaging article and its foldable lined structure packaged therein, a structural strength and an elastic force of a position where is folded in the lined structure are still insufficient. In a case while the object packaged within the conventional pulp-molded packaging article comes to suffer accidental collision during transportation, the folded lined structure within the pulp-molded packaging article would be hard to provide an effective cushioning protection for the packaged object therein, resulting in poor workability of the packaging article.

[0005] Hence, for solving the afore-mentioned technical issues of the conventional paper-made boxes, it is essential to propose an improved structure for the paper-made boxes.

SUMMARY OF THE INVENTION

[0006] In order to solve the aforementioned technical problems of the conventional arts, an objective of the present invention is to provide a pulp-molded packaging article where its whole structure is integrally formed by a wet fiber pulp-molding process, which avoids a damage to an ecological environment, and avoids the above technical problems resulted from the conventional paper-made boxes, including, for example, laboriousness and the large of time consumption in their fabrications which uses the manufacturing steps of: cropping the cardboard to have use-to-joint side edges, reversely folding each of the side edges of the cardboard on an interconnection thereof to form respective standing sidewalls, boring through the standing sidewalls to form respective snap-in apertures thereon, and then assembling the conventional paper-made box in manual.

[0007] Another objective of the present invention is to provide a pulp-molded packaging article in which its whole structure is completely and integrally formed, without a need of extra adding a formed-by-folding lined structure thereto, by a wet fiber pulp-molding process, thereby being not only capable of raising both a structural strength and an elastic force of the whole pulp-molded packaging article but also being capable of providing several functions of cushioning protection, rapid orientation and effective snap-in retention, for a to-be-packaged object which is packaged in pulp-molded packaging article.

[0008] In order to accomplish the above inventive objectives, the present invention provides a technical solution with a pulp-molded packaging article, which is integrally formed by a wet fiber pulp-molding process, used for carrying a to-be-packaged object thereon. The pulp-molded packaging article is primary structured with a horizontal bottom wall and a standing lateral wall.

[0009] The standing lateral wall is integrally extended upwardly from and around an outermost periphery of the horizontal bottom wall. The standing lateral wall is formed with an inner sidewall and an outer sidewall located opposite to the inner sidewall. The standing lateral wall is formed with transversely cross-sectional thicknesses between the inner sidewall and the outer sidewall. An accommodation space is defined commonly by between the horizontal bottom wall and the standing lateral wall, for accommodating the to-be-packaged object. A top opening communicated with the accommodation space is formed adjacent to the top of the standing lateral wall, used for providing entry or exit of the to-be-packaged object.

[0010] The transversely cross-sectional thickness located at the bulge region is larger than the transversely cross-sectional thickness located at the groove region. The standing lateral wall further comprises a bulge region located beneath the top opening and a groove region located beneath the bulge region. The bulge region and the groove region both are integrally formed side-by-side along a direction in which the standing lateral wall is upwardly extended. The bulge region is formed with a snap-in convex surface which is protruded from the inner sidewall toward the accommodation space, and the groove region is formed with a concave surface which is concaved from the inner sidewall toward the outer sidewall. While the to-be-packaged object enters into the accommodation space to oppress the snap-in convex surface, the bulge region is therefore actuated in elastic deformation to reach an outwardly deflected position. After the to-be-packaged object continues to pass through beside the snap-in convex surface to reach the concave surface of the groove region, the bulge region is rebounded therefore to exert reverse elastic forces on the to-be-packaged object, resulting in a snap-in retention onto the to-be-packaged object, which makes the snap-in convex surface stopping the to-be-packaged object from moving toward the top opening.

[0011] In a preferred embodiment, the bulge region and the groove region both located on the outer sidewall are revealed in a successively-flat curve surface formed along the upwardly-extended direction.

[0012] In a preferred embodiment, an inner contour of the inner sidewall conforms with an outer contour of the to-be-packaged object.

[0013] In a preferred embodiment, an upper of the bulge region has a guiding inclined curved plane formed on the inner sidewall, which is used to direct the to-be-packaged object into the accommodation space by an inclined plane principle.

[0014] In a preferred embodiment, the snap-in convex surface of the bulge region is formed in a shape of a snap-in annular bar along an inner circumferential direction of the inner sidewall, and the concave surface of the groove region is formed in a shape of a snap-in annular recess along the inner circumferential direction of the inner sidewall.

[0015] In a preferred embodiment, the transversely cross-sectional thickness located at the bulge region is larger than the transversely cross-sectional thickness of the other portions of the standing lateral wall.

[0016] In a preferred embodiment, a draft direction of the bulge region has a negative draft angle relative to a longitudinal draft direction of the inner sidewall of the standing lateral wall.

[0017] In a preferred embodiment, the concave surface is integrally connected side-by-side with the snap-in convex surface along the upwardly-extended direction of the standing lateral wall.

[0018] The present invention brings the following technical efficiencies that: in comparison with the conventional arts, a whole structure of the pulp-molded packaging article according to the present invention is integrally formed by a wet fiber pulp-molding process, thereby being capable of avoiding a damage to the ecological environment; furthermore, adopting the wet fiber pulp-molding process does not only strengthen both an elastic force and a structural strength of the pulp-molded packaging article but also avoid having the same technical issues, of laboriousness and a large of time consumption, as resulted from the conventional paper-made boxes; and moreover, in the present invention, since the whole structure of the pulp-molded packaging article is integrally formed entirely by way of the wet fiber pulp-molding process, without the need of extra increasing a formed-by-folding lined structure therein, it is capable of providing several functions of cushioning protection, rapid orientation and effective snap-in retention, for a to-be-packaged object which is carried inside the article.

DESCRIPTION OF THE DIAGRAMS

[0019] Fig. 1 depicts a perspective view of a pulp-molded packaging article according to the present invention; [0020] Fig. 2A depicts a lateral side view of the pulp-molded packaging article shown in Fig. 1; [0021] Fig. 2B depicts a cross-sectional view of the pulp-molded packaging article according to a sectioning line A-A shown in Fig. 2A; [0022] Fig. 3A depicts a partially enlarged view of a circled region Cl drawn in the pulp-molded packaging article shown in Fig. 2B; [0023] Fig. 3B depicts a partially enlarged view where the pulp-molded packaging article shown in Fig. 3A, where the pulp-molded packaging article is being ready to accommodate a to-be-packaged object; [0024] Fig. 3C depicts a partially enlarged view where the pulp-molded packaging article shown in Fig. 3B, where the pulp-molded packaging article starts accommodating the to-be-packaged object; [0025] Fig. 3D depicts a partially enlarged view where the pulp-molded packaging article shown in Fig. 3C, where the pulp-molded packaging article has accommodated the to-be-packaged object therein; and [0026] Fig. 4 depicts a laterally cross-sectional view of the pulp-molded packaging article shown in Fig. 3D, where the pulp-molded packaging article has accommodated the to-be-packaged object therein.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

1-00271 The technical proposals in the embodiments of the present invention will be clearly and completely described in the following with reference to the accompanying drawings of the embodiments of the present invention. The directional terms mentioned in the present invention, such as "upper", "lower", "before", "after", "left", "right", "inside", "outside", "side", etc., are merely illustrative the direction of the drawing. Therefore, the directional terminology used is for the purpose of illustration and understanding of the invention, which is not intended to limit the invention.

[0028] First of all, please refer to the illustrations shown in Figs. 1 and 2A, wherein Fig. 1 depicts a perspective view of the pulp-molded packaging article 1 according to the present invention, and Fig. 2A depicts a lateral side view of the pulp-molded packaging article 1 shown in Fig. 1. The pulp-molded packaging article 1 where a whole structure thereof is integrally formed entirely by a wet fiber pulp-molding process is used to carry a to-be-packaged object 50 thereon (See Fig. 3B). In details, The pulp-molded packaging article 1 is primary structured with a horizontal bottom wall 10, a standing lateral wall 20 and a connecting plate 40. In this preferred embodiment, the pulp-molded packaging article 1 is realized as a paper-made tray but is not therefore limited thereto. The pulp-molded packaging article 1 according to the present invention may be manufactured into a variety of geometric shapes; and in particular, a geometric shape which is commonly constituted by the horizontal bottom wall 10 and the standing lateral wall 20, may include, for example, one of cylinder, rectangular body, cube, pyramid, cone, curved body, gengon and so forth, but is not therefore limited thereto. The to-be-packaged object 50 (See Fig. 3B) is realized as a solid structure, which may include, for example, one of cosmetic, a variety of ornaments, a variety of 3C electronic products and so forth, but is not therefore limited thereto.

[0029] In this embodiment, the wet fiber pulp-molding process used to manufacture the pulp-molded packaging article 1 according to the present invention is a conventional manufacturing technology; nonetheless, in order to be conveniently realized, a number of essential steps implemented in the wet fiber pulp-molding process are introduced as follows in simplicity, which comprise: (1) by a set of male and female mold assembly (not shown) for sucking pulps made up of plant fibers and then applying initial compressions on the sucked pulps, achieving a wet rough body made of the plant fibers; then, (2) the male and female mold assembly further applying compressive forces in an upward-and-downward matching manner for the wet rough body, thereby shaping a semi-finished article from the wet rough body; then, (3) by at least one set of thermo-compression forming male and female mold assembly (not shown) acting on an upward-and-downward matching manner for the semi-finished article, thereby integrally thermo-compressively forming the whole structure of the pulp-molded packaging article 1 which comprises the horizontal bottom wall 10, the standing lateral wall 20 and the connecting plate 40; and then (4)removing excessive leftover bits located around a periphery of the pulp-molded packaging article 1. Alternatively, it can not be limited to the afore-mentioned introduction. Any other pulp-molding process that is capable of being adopted to manufacture the pulp-molded packaging article 1 of the present invention belongs to the wet fiber pulp-molding process designated in the present invention.

[0030] Further referring to the illustrations shown in Figs. 1 and 2B, Fig. 2B depicts a cross-sectional view of the pulp-molded packaging article along a sectioning line A-A shown in Fig. 2A. The horizontal bottom wall 10 has a longitudinal center line X which vertically passes through the horizontal bottom wall 10. The standing lateral wall 20 is upwardly extended integrally from and around an outermost periphery of the horizontal bottom wall 10. In a preferred embodiment, the standing lateral wall 20 is rendered as a annular structure surrounding the horizontal bottom wall 10. A accommodation space 30 is commonly defined by between the horizontal bottom wall 10 and the standing lateral wall 20, for accommodating the to-be-packaged object 50 (as referring to the illustrations shown in Figs. 3B) therein. The standing lateral wall 20 is further formed with an inner sidewall 201 facing the accommodation space 30, and an outer sidewall 203 located opposite to the inner sidewall 201. On a top of the standing lateral wall 20, where is adjacent to the connecting plate 40, a top opening 26 is formed in communicating with the accommodation space 30. The top opening 26 is used to provide entry or exit of the to-be-packaged object 50 (See Fig. 3B) for the accommodation space 30. In another preferred embodiment, within the top opening 26 defined by the top of the standing lateral wall 20, an inner contour of the inner sidewall 201 conforms with an outer contour of an outer circumferential curve surface of the to-be-packaged object 50 (See Fig. 3B) or a size proportion of the outer contour, but is not therefore limited thereto.

[0031] As illustrated in Figs. 1 and 2B, the connecting plate 40 is integrally formed with and around an outermost circumference of the top of the standing lateral wall 20, and is outwardly and horizontally extended in radial directions from the outermost circumference of the top of the standing lateral wall 20; nevertheless, in other embodiment, both of a distance and a planar shape where the connecting plate 40 of the pulp-molded packaging article 1 is horizontally extended are not limited since such a connecting plate 40 can also be permitted, which is just able to strengthen both the structural strength and the elastic force of the standing lateral wall 20, thereby preventing the standing lateral wall 20 from having a permanent deformation while the to-be-packaged object 50 (See Fig. 3B) is accommodated within the article 1. In another embodiment, the connecting plate 40 of the pulp-molded packaging article 1 may be omitted in a case of disuse.

[0032] Referring to the illustrations shown in Figs. 1, 2B and 3A, Fig. 3A depicts a partially enlarged view according to a circled region Cl drawn in the pulp-molded packaging article shown in Fig. 2B. The standing lateral wall 20 further has a bulge region 22 located beneath the top opening 26, and a groove region 24 located beneath the bulge region 22. The groove region 24 and the bulge region 22 both are integrally formed side-by-side along a direction S where the standing lateral wall 20 is upwardly extended. The upwardly-extended direction S is the same as a longitudinal draft direction S of the inner sidewall 201 of the standing lateral wall 20 upon molding. The bulge region 22 has a snap-in convex surface 222 (as defined with a longest inward-protruded length) which is protruded from the inner sidewall 201 toward the accommodation space 30). And, the groove region 24 has a concave surface 246 which is concaved successively from the inner sidewall 201 toward the outer sidewall 203. The concave surface 246 is integrally connected with beneath the snap-in convex surface 222. In this embodiment, both the concave surface 246 and the snap-in convex surface 222 of the inner sidewall 201 are integrally formed, such as two side-by-side connected peak and trough structures, in an down-to-up sequential arrangement along the upwardly-extended direction S. In this preferred embodiment, on an upper of the bulge region 22 (as a position upwardly corresponding to the top opening 26), the bulge region 22 further has a guiding inclined curved plane 224 formed on the inner sidewall 201. The guiding inclined curved plane 224 is integrally connected with and located above the snap-in convex surface 222.

[0033] In a preferred embodiment, the snap-in convex surface 222 of the bulge region 22 is formed in a shape of a snap-in annular bar arranged in a successive arrangement (See Fig. 1), or a plurality of snap-in annular bars arranged in a spaced arrangement, along an inner circumferential direction of the inner sidewall 201. And similarly, the concave surface 246 is formed in a shape of a snap-in annular recess arranged in a successive arrangement, or a plurality of snap-in annular recesses arranged in a spaced arrangement, along the inner circumferential direction of the inner sidewall 201.

[0034] As illustrated in Figs. 2B and 3A, regions between both the inner sidewall 201 and the outer sidewall 203 of the standing lateral wall 20 are formed with different transversely cross-sectional thicknesses (e.g. W1, W2) whereas most of the regions between both the inner sidewall 201 and the outer sidewall 203 are formed with the transversely cross-sectional thickness W2, and the transversely cross-sectional thickness W1 located at the snap-in convex surface 222 of the bulge region 22 is larger than the transversely cross-sectional thickness W2 of the other most regions of the standing lateral wall 20; and in particular, the transversely cross-sectional thickness W1 located at the bulge region 22 is larger than the transversely cross-sectional thickness W2 (i.e. W1>W2) located at the groove region 24, namely a thickness difference (i.e. W1-W2) occurring between the different transversely cross-sectional thicknesses W1, W2, which are inwardly protruded from the inner sidewall 201 to result in an uneven-thickness manner. It should be noted that, since the concave surface 246 is located beneath the snap-in convex surface 222, the concave surface 246 has a transversely cross-sectional thickness that is successively narrowed, downwardly; conversely, since the guiding inclined curved plane 224 is located on an upper of the snap-in convex surface 222, the guiding inclined curved plane 224 has a transversely cross-sectional thickness that is successively widened, downwardly. In the present invention, using the wet fiber pulp-molding process to integrally form the bulge region 22 with the transversely cross-sectional thickness W1 which is more thickened than the thicknesses of other regions, thereby providing the to-be-packaged object 50 (See Fig. 3B) with several functions of cushioning protection and rapid orientation while raising both a structural strength and an elastic force for the to-be-packaged object 50 (See Fig. 3B), rather than using the conventional process of folding the cardboard to form. Accordingly, the groove region 24 and the bulge region 22 both located on the outer sidewall 203 are kept revealed in a successively-flat curve surface formed along the upwardly-extended direction S; nonetheless, the groove region 24 and the bulge region 22 both located at the inner sidewall 201 are revealed as a successively-formed structures with a set of peak and trough, both of which are side-by-side connected with each other along the upwardly-extended direction S. [0035] Besides, in this preferred embodiment as depicted in Figs. 2B and 3A, while the whole structure of the pulp-molded packaging article 1 is integrally formed by the respective sets of male and female mold assemblies (not shown) used in the wet fiber pulp-molding process, a draft direction K1 of the bulge region 22 has a negative draft angle a relative to the longitudinal draft direction S of the inner sidewall 201 of the standing lateral wall 20.

[0036] Further referring to the illustrations shown in Figs. 2B and 3B, Fig. 3B depicts a partially enlarged view of the pulp-molded packaging article 1 shown in Fig. 3A, where the pulp-molded packaging article 1 is being ready to accommodate the to-be-packaged object 50. While the to-be-packaged object 50 suffers an external compressive force P1 to downwardly pass through the top opening 26 in a way of being ready to enter into the accommodation space 30, the to-be-packaged object 50 would precedently engage with the guiding inclined curved plane 224 of the bulge region 2. Next, the guiding inclined curved plane 224 directs the to-be-packaged object 50 to downwardly slide toward the accommodation space 30, by a way of an inclined plane principle, along an outer surface formed on the guiding inclined curved plane 224, until the to-be-packaged object 50 starts entering into the accommodation space 30.

[0037] Further referring to the illustrations shown in Figs. 3B and 30, Fig. 30 depicts a partially enlarged view of the pulp-molded packaging article 1 shown in Fig. 3B, where the pulp-molded packaging article 1 starts accommodating the to-be-packaged object therein. While the to-be-packaged object 50 continuously suffers the external compressive force P1 to slide on the guiding inclined curved plane 224 until the to-be-packaged object 50 oppresses the snap-in convex surface 222, the bulge region 22 or the standing lateral wall 20 is therefore actuated so as to generate an outward elastic deformation Ti with an outward displacement dl to reach an outward deflection position. In the start time, only few of portions of the to-be-packaged object 50 has entered into the accommodation space 30. As long as the to-be-packaged object 50 oppresses the snap-in convex surface 222 to facilitate either the bulge region 22 or the standing lateral wall 20 generating the outward elastic deformation Ti with the outward displacement dl to reach the outward deflection position, the connecting plate 40 located around the outermost circumferential direction of the top of the standing lateral wall 20 can strengthen the standing lateral wall 20 to essentially have a sufficient structural strength, and a sufficient elastic force that can prevent the elastic deformation Ti of either the bulge region 22 or the standing lateral wall 20 from transiting into a permanent deformation.

[0038] Further referring to the illustrations shown in Figs. 3C and 3D, Fig. 3D depicts a partially enlarged view of the pulp-molded packaging article 1 shown in Fig. 3C, where the pulp-molded packaging article 1 has completely accommodated the to-be-packaged object 50 therein. While an outer side edge of the to-be-packaged object 50 has passed through beside the snap-in convex surface 222 to continuously downwardly reach the concave surface 246 of the groove region 24, the snap-in convex surface 222 of the bulge region 22 is rebounded therefore to exert reverse elastic forces T2 on the outer side edge of the to-be-packaged object 50 so as to snap-in retention onto the outer side edge of the to-be-packaged object 50, which makes the snap-in convex surface 222 generating a snap-in retentive effect of stopping the to-be-packaged object 50 from an outward movement toward the top opening 26. In a case, most of the structure of the to-be-packaged object 50 can be effectively fixed within the accommodation space 30 (as referring to Fig. 4), rather than being readily moved outside or even departed from the article 1.

[0039] In conclusion, since the whole structure of the pulp-molded packaging article 1 according to the present invention is integrally formed by the wet fiber pulp-molding process, it is capable of avoiding the damage to the ecological environment, strengthening both the elastic force and the structural strength of the pulp-molded packaging article 1, and avoiding the technical issues resulted from the above-mentioned conventional paper-made boxes, such as laboriousness and a large of time consumption in their fabrications. Besides, by the wet fiber pulp-molding process to integrally form the whole structure without the need of extra increasing a formed-by-folding lined structure, the pulp-molded packaging article 1 according to the present invention can provide several functions of effective cushioning protection, rapid orientation and effective snap-in retention, for the to-be-packaged object 50 which is packaged in the article 1.

[0040] As described above, although the present invention has been described with the preferred embodiments thereof, those skilled in the art will appreciate that various modifications, additions, and substitutions are possible without departing from the scope and the spirit of the invention. Accordingly, the scope of the present invention is intended to be defined only by reference to the claims.

Claims

Claims What is claimed is: 1. A pulp-molded packaging article, integrally formed by a wet fiber pulp-molding process, for carrying a to-be-packaged object thereon, comprising: a horizontal bottom wall; and a standing lateral wall, integrally and upwardly extended from and around an outermost periphery of the horizontal bottom wall, wherein the standing lateral wall is formed with an inner sidewall and an outer sidewall located opposite to the inner sidewall, the standing lateral wall is formed with transversely cross-sectional thicknesses between the inner sidewall and the outer sidewall, an accommodation space is defined commonly by between the horizontal bottom wall and the standing lateral wall, for accommodating the to-be-packaged object therein, and a top opening communicated with the accommodation space is formed adjacent to a top of the standing lateral wall, for providing entry or exit of the to-be-packaged object; and characterized in that, the standing lateral wall comprises a bulge region located beneath the top opening, and a groove region located beneath the bulge region, both the bulge region and the groove region are integrally formed side-by-side along a direction in which the standing lateral wall is upwardly extended, the bulge region is formed with a snap-in convex surface which is protruded from the inner sidewall toward the accommodation space, and the groove region is formed with a concave surface which is concaved from the inner sidewall toward the outer sidewall, wherein the transversely cross-sectional thickness located at the bulge region is larger than the transversely cross-sectional thickness located at the groove region, and while the to-be-packaged object enters into the accommodation space to oppress the snap-in convex surface, the bulge region is therefore actuated in elastic deformation to reach an outwardly deflected position, and after the to-be-packaged object continues to pass through beside the snap-in convex surface to reach the concave surface of the groove region, the bulge region is rebounded therefore to exert reverse elastic forces on the to-be-packaged object, resulting in a snap-in retention onto the to-be-packaged object, which makes the snap-in convex surface stopping the to-be-packaged object from moving toward the top opening.
2. The pulp-molded packaging article according to any preceding claim, characterized in that, the bulge region and the groove region both located on the outer sidewall are revealed in a successively-flat curve surface formed along the upwardly-extended direction.
3. The pulp-molded packaging article according to any preceding claim, characterized in that, an inner contour of the inner sidewall conforms with an outer contour of the to-be-packaged object.
4. The pulp-molded packaging article according to any preceding claim, characterized in that, an upper of the bulge region has a guiding inclined curved plane formed on the inner sidewall, which is used to direct the to-be-packaged object into the accommodation space by an inclined plane principle.
5. The pulp-molded packaging article according to any preceding claim, characterized in that, the snap-in convex surface of the bulge region is formed in a shape of a snap-in annular bar along an inner circumferential direction of the inner sidewall, and the concave surface of the groove region is formed in a shape of a snap-in annular recess along the inner circumferential direction of the inner sidewall.
6. The pulp-molded packaging article according to any preceding claim, characterized in that, the transversely cross-sectional thickness located at the bulge region is larger than the transversely cross-sectional thickness of the other portions of the standing lateral wall.
7. The pulp-molded packaging article according to any preceding claim, characterized in that, a draft direction of the bulge region has a negative draft angle relative to a longitudinal draft direction of the inner sidewall of the standing lateral wall.
8. The pulp-molded packaging article according to any preceding claim, characterized in that, the concave surface is integrally connected side-by-side with the snap-in convex surface along the upwardly-extended direction of the standing lateral wall.