Search

CN-122009647-A - Container and preparation process thereof

CN122009647ACN 122009647 ACN122009647 ACN 122009647ACN-122009647-A

Abstract

The invention relates to a container and a preparation process thereof, the container comprises a base and a plurality of side plates assembled on the base, the side plates define a space for accommodating articles, at least one side plate comprises a side plate body made of plastic, the side plate body comprises at least one thick wall area and at least one thin wall area, the thick wall area is a local area of the side plate body, the thin wall area is the rest area of the side plate body, the average porosity of the thick wall area is larger than that of the thin wall area, the thick wall area comprises a dense area positioned on a surface layer and a foaming area positioned inside, the average porosity of the dense area is smaller than that of the foaming area, the thick wall area is locally reinforced through the foaming area inside, so that traditional reinforcing ribs are not required to be arranged, the surface of the container is kept smooth, and the problems of difficult cleaning, dirt residues and scraping damage to the loaded articles are effectively solved.

Inventors

  • Request for anonymity
  • Request for anonymity

Assignees

  • 浙江箱箱智能包装有限公司

Dates

Publication Date
20260512
Application Date
20260408

Claims (15)

  1. 1. A container, comprising: A base, and A plurality of side plates assembled on the base, wherein the side plates define a space for accommodating articles; Wherein at least one of the side plates comprises a side plate body made of plastic, the side plate body comprising: A thick-wall region, which is a local region of the side plate body, wherein the wall thickness of the thick-wall region is larger than the average wall thickness of the side plate body; The thin-wall area is the rest area of the side plate body, and the wall thickness of the thin-wall area is smaller than that of the thick-wall area; wherein the average porosity of the thick-wall area is larger than that of the thin-wall area, and the thick-wall area comprises a compact area positioned on the surface layer and a foaming area positioned inside, and the average porosity of the compact area is smaller than that of the foaming area.
  2. 2. The container of claim 1, wherein the foaming zone is formed by a physical micro-foaming process.
  3. 3. The container of claim 1, wherein the thick-walled region comprises a first reinforcement disposed at a periphery of the side panel body.
  4. 4. A container according to claim 3, wherein the first reinforcement is in a closed loop or open loop configuration extending along the periphery of the side panel body.
  5. 5. A container according to claim 3, wherein the thick-walled region further comprises a second reinforcing portion which is located in the middle of the side plate body and extends in the height direction of the side plate body and connects the first reinforcing portion; The thin-wall region is located in a region surrounded by the first reinforcing portion and the second reinforcing portion.
  6. 6. The container of claim 1, wherein a gas assist channel is further provided in the thick-walled region, the gas assist channel extending along a periphery of the side panel body.
  7. 7. The container of claim 6, wherein only one blocking portion is provided in the gas-assist channel, the blocking portion blocking the gas-assist channel and causing the gas-assist channel to form a start section and an end section of the channel on opposite sides of the blocking portion.
  8. 8. The container according to claim 7, wherein the start section and the end section are provided with an air inlet and an air outlet, respectively, which communicate with the outside.
  9. 9. The container of claim 7, wherein the barrier is formed by a wall comprising the foaming region.
  10. 10. The container of claim 9, wherein the barrier is internally provided with a hollow chamber.
  11. 11. The container of claim 1, wherein the outer surface of the side panels is substantially smooth planar and/or curved.
  12. 12. A process for preparing a container according to any one of claims 1 to 11, comprising the steps of: providing a mold having a cavity with different mold gaps corresponding to a designed wall thickness of the thick-walled region and the thin-walled region; Melting a polymer material and injecting a supercritical fluid into the polymer melt to form a homogeneous polymer melt containing the supercritical fluid; Injecting the polymer melt containing the supercritical fluid into a mold cavity, and inducing microcellular foaming by using pressure drop; cooling and shaping, opening the mould and taking out to obtain the container.
  13. 13. The process according to claim 12, wherein in the injecting step, micropores in the thick-walled region sufficiently grow to form a foamed region, and foaming is suppressed to form a dense region in the surface layer of the thick-walled region and the thin-walled region.
  14. 14. A process for preparing a container according to any one of claims 1 to 11, comprising the steps of: providing a mold having a cavity with different mold gaps corresponding to a designed wall thickness of the thick-walled region and the thin-walled region; Melting a first polymeric material and injecting a supercritical fluid into the first polymeric melt to form a homogeneous first polymeric melt comprising the supercritical fluid; Sequentially injecting the second polymer material and the first polymer material into the same mold, wherein the second polymer material forms a cavity in a thick-wall area, and the first polymer material pushes and fills the cavity in a molten state of the cavity material; cooling and shaping, opening the mould and taking out to obtain the container.
  15. 15. The process of claim 14 wherein during the injecting step the second polymeric material forms a dense zone and the first polymeric material induces a bubble nucleus in the mold due to pressure drop and grows in the mold cavity corresponding to the thick wall zone, forming a foamed zone in the mold cavity.

Description

Container and preparation process thereof Technical Field The invention relates to the technical field of logistics containers, in particular to a container and a preparation process thereof. Background In modern logistics and supply chain systems, recyclable plastic packaging containers, such as turn-around boxes, trays, logistics boxes, etc., play a vital role. Such carriers are generally manufactured in batches by injection molding processes, and most of the materials are polypropylene (PP), high Density Polyethylene (HDPE), or co-polypropylene. In order to control the material cost and the weight of the parts and simultaneously ensure that the container has enough structural strength, rigidity and fatigue resistance under complex working conditions such as stacking, carrying, transporting and the like, the traditional design generally adopts a reinforcing rib structure. The ribs are typically ribs extending perpendicular or at an angle to the main wall surface on the inner or outer surface of the container wall panels (e.g., side panels, bottom panels). Through the reasonable arrangement of the crisscross reinforcing rib network, the moment of inertia of the plate-shaped structure can be greatly improved, so that obvious rigidity enhancement is realized with fewer material increment. This is a classical approach to the lightweight design of engineering plastic articles. However, criss-cross grooves, ravines or grid-like voids are inevitably formed between the reinforcing ribs. These areas are extremely prone to dust, oil, product residues (e.g., food scraps, chemical dust) and microorganisms. Conventional cleaning methods (such as high-pressure water gun flushing and soaking cleaning) are difficult to thoroughly remove dirt in the deep and narrow grooves, and often require manual brushing or more complex cleaning processes, thereby increasing operation cost and downtime. In addition, a hollow air passage is formed in a part of the large container in the thick-wall area of the product, so that sizing materials can be greatly saved, the weight can be reduced, and sink marks can be reduced on the premise of ensuring the strength. However, in order to prevent the gas from flowing out of the preset air passage, the gas-assisted process must design specific blocking points on the mold. The positions of the blocking points become weak points on the structure of the product, the mechanical property is reduced, and the product can crack under long-term cyclic load or accidental impact. The design of the airway is to ensure that the gas flows smoothly and fills the predetermined area, which generally means that the airway must be a relatively simple, consistent, and low resistance path. Complex or closed annular reinforcing structures often need to be divided into multiple independent air passages and separated by multiple barrier points, which in turn increases the structural weakness of the article. In addition, gas-assist molding requires materials with higher melt flow rates, while high flow materials tend to be sacrificed in toughness that can impact the durability and life of the container under low temperature or impact conditions. Thus, there is a need in the marketplace for a new container that fundamentally overcomes the above-described drawbacks, with a seamless or near-seamless inner wall surface, higher structural integrity and material toughness, better cleaning convenience, while maintaining or even improving its load-bearing properties and light weight levels. Disclosure of Invention The invention aims to provide a container which is structurally optimized by combining a physical micro-foaming process. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: a container, comprising: A base, and A plurality of side plates assembled on the base, wherein the side plates define a space for accommodating articles; Wherein at least one of the side plates comprises a side plate body made of plastic, the side plate body comprising: A thick-wall region, which is a local region of the side plate body, wherein the wall thickness of the thick-wall region is larger than the average wall thickness of the side plate body; The thin-wall area is the rest area of the side plate body, and the wall thickness of the thin-wall area is smaller than that of the thick-wall area; wherein the average porosity of the thick-wall area is larger than that of the thin-wall area, and the thick-wall area comprises a compact area positioned on the surface layer and a foaming area positioned inside, and the average porosity of the compact area is smaller than that of the foaming area. In one embodiment, the foaming region is formed by a physical micro-foaming process. In one embodiment, the thick-walled region includes a first reinforcement disposed at a periphery of the side plate body. In one embodiment, the first reinforcement portion is a closed loop structure or an open loop structure