Plastic molded products and method for preparing same

Abstract

Provided is a plastic molded product, the plastic molded product of the present invention being a plastic molded product at least one surface of which is provided with a 3D digital code pattern, the 3D digital code being formed via injection-molding of the plastic molded product.

Description

Plastic molded products and their manufacturing methods

[0001] The present invention relates to a plastic molded product and a method for manufacturing the same. More specifically, the present invention relates to an environmentally friendly plastic molded product and a method for manufacturing the same, which eliminates the need for conventional 2D digital codes (QR and bar codes) implemented through labels or post-processing and instead recreates them in three dimensions as part of the plastic component. Furthermore, the present invention provides a plastic molded product and a method for manufacturing the same, which exhibits excellent recognition rates regardless of color or pattern type.

[0002]

[0003] Most packages and consumer goods feature 2D / 3D digital codes (Quick Response Codes) or bar codes, as shown in Figures 1(a) to (d), attached as stickers / labels or applied through post-processing such as printing / etching to convey product information. However, from an environmental perspective, these codes are considered pollutants, reducing the recyclability of the components. Furthermore, labels and etchings can peel off or fade over time.

[0004] In this way, 2D digital codes attached / printed on plastic consumer goods are considered pollutants from an environmental perspective, which reduces the recyclability of the parts, and may be removed or erased over time. Therefore, it is necessary to form digital codes as part of the plastic parts without the need for printing, attachment, etc.

[0005] To solve the above problem, a technology for engraving using laser processing is being considered, but it is not practical due to the need for separate post-processing and the waste of time and energy.

[0006] Meanwhile, used plastic waste is collected and recycled, typically sorted by material, such as PET, PP, LDPE, PS, HDPE, PVC, and other materials. However, if the plastic waste is damaged or its material is unknown, sorting it is difficult and thus cannot be recycled. This leads to environmental pollution and increased costs associated with sorting by material.

[0007] Therefore, there is a need to develop plastic products and their manufacturing methods that do not require labeling or post-processing and can be easily recycled even if damaged.

[0008] Furthermore, the inventors have developed a method for forming a 3D digital code pattern on a plastic molded product simultaneously with injection molding by imprinting the pattern onto the mold during plastic injection molding. However, if the pattern is embossed or the molded product is dark in color, the recognition rate is reduced.

[0009] Therefore, there is a need to develop a plastic molded product and its manufacturing method having a 3D digital code with excellent recognition rate regardless of color or pattern shape.

[0010] The relevant prior art is Korean Patent No. 1597471.

[0011]

[0012] The purpose of the present invention is to provide a plastic molded product and a method for manufacturing the same that does not require label attachment or post-processing.

[0013] Another object of the present invention is to provide a plastic molded product having an excellent recognition rate regardless of color or pattern shape and a method for manufacturing the same.

[0014] Another object of the present invention is to provide a plastic molded product and a method for manufacturing the same, which can achieve both recyclability and aesthetics by including a 3D digital code in the opening of the plastic molded product in which an opening is formed as a passage through which sound, air, liquid, and gas flow in and out.

[0015] Another object of the present invention is to provide a plastic molded product and a method for manufacturing the same, which can be easily classified and recycled by reading recycling information through a digital code even if a part of the product is damaged.

[0016] Another object of the present invention is to provide a plastic molded product and a method for manufacturing the same that can be easily manufactured through a single injection molding process without subsequent processes such as attachment or perforation.

[0017] Another object of the present invention is to provide a plastic molded product and a manufacturing method thereof that can apply a 3D digital code to a curved surface.

[0018] Another object of the present invention is to provide a plastic molded product and a manufacturing method thereof that can contain product-related information while providing a design effect by applying a 3D digital code to a large area.

[0019] Another object of the present invention is to provide a plastic molded product and a method for manufacturing the same that can contribute to closed-loop recycling and a circular economy.

[0020] Another object of the present invention is to provide a method for forming a 3D digital code with improved injection properties that can reduce the defect rate during injection molding in molding a plastic molded product that does not require label attachment or post-processing, a mold therefor, and a plastic molded product formed therefrom.

[0021] Another object of the present invention is to provide a method for forming a 3D digital code, a mold therefor, and a plastic molded product formed therefrom, which contributes to reducing carbon emissions by regenerating a conventional 2D digital code (QR and Bar) implemented as a label or post-processing into a three-dimensional shape as part of a plastic part through a single injection molding, while improving the injection properties of a fine 3D digital code and enhancing the recognition rate.

[0022] Another object of the present invention is to provide a method for forming a 3D digital code, which improves mold damage and enhances injection properties by modifying a 3D digital code design, a mold therefor, and a plastic molded product formed therefrom.

[0023] The above and other objects of the present invention can all be achieved by the present invention described below.

[0024]

[0025] 1. One aspect of the present invention relates to a plastic molded product. The plastic molded product is a plastic molded product having a three-dimensional (3D) digital code pattern formed three-dimensionally on at least one surface, wherein the 3D digital code stores information including the type of material for classification and recycling of the plastic molded product, and is formed by injection molding the plastic molded product, and the 3D digital code is made of the same material as the plastic molded product and is formed integrally with the plastic molded product.

[0026] 2. In the above 1 specific example, the 3D digital code may be a QR code or a barcode.

[0027] 3. In the above 1 or 2 specific examples, the 3D digital code pattern may have an engraved pattern, a relief pattern, or a perforated pattern.

[0028] 4. In the above specific examples 1 to 3, the 3D digital code has a thickness, and the thickness may be about 1.0 mm or more.

[0029] 5. In the above specific examples 1 to 4, the 3D digital code may not be printed.

[0030] 6. In the above 1 to 5 specific examples, the 3D digital code pattern may be formed on about 30% or more, about 50% or more, about 70% or more, about 80% or more, about 85% or more, about 90% or more, about 95% or more, about 99% or more or the entire surface of the plastic molded product.

[0031] 7. In the above specific examples 1 to 6, the 3D digital code pattern may be formed by double injection.

[0032] 8. In the above 1 to 7 specific examples, the plastic molded product is a plastic molded product having an opening formed on at least one side, the opening through which a fluid including gas, liquid or sound can pass, and the opening includes the 3D digital code and can be recognized by a terminal.

[0033] 9. In the above 1 to 8 specific examples, the opening may include a speaker grill, a vent hole, an air purifier exhaust port, a humidifier exhaust port, a home appliance vent hole, a vacuum cleaner exhaust port, or a food packaging container exhaust port.

[0034] 10. In the above specific examples 1 to 9, the 3D digital code can be formed on a curved surface.

[0035] 11. Another aspect of the present invention is a method for manufacturing a plastic molded product. The method comprises the steps of: injection molding molten plastic using a mold engraved with a 3D digital code; and separating the injected plastic molded product from the mold; wherein the 3D digital code stores information including the type of material for classifying and recycling the plastic molded product.

[0036] 12. In the above 11 specific examples, the plastic molded product may have a 3D digital code pattern formed three-dimensionally on at least one surface.

[0037] 13. In the above 11 or 12 specific examples, the plastic molded product has an opening formed on at least one side, the opening can pass a fluid including gas, liquid or sound, and the opening includes a 3D digital code and can be recognized by a terminal.

[0038] 14. In the above 11 to 13 specific examples, the plastic molded product may have a 3D digital code pattern formed openly on at least one surface, and the open 3D digital code pattern and the plastic molded product may be formed integrally.

[0039] 15. Another aspect of the present invention relates to a plastic molded product according to another specific embodiment. The plastic molded product has a three-dimensional (3D) digital code pattern formed three-dimensionally on at least one surface, the 3D digital code including a concave portion and a protruding portion, and is formed by injection molding the plastic molded product, and is characterized in that either the concave portion or the protruding portion has a diffusely reflective surface or a glossy surface.

[0040] 16. In the above 15 specific examples, the 3D digital code is made of the same material as the plastic molded product and is formed integrally with the plastic molded product.

[0041] 17. In the above 15 or 16 specific examples, the 3D digital code is made of the same material as the plastic molded product and is formed integrally with the plastic molded product.

[0042] 18. Another aspect of the present invention is a method for recovering waste plastic. The method is a method for recovering waste plastic using a 3D digital code, and the method includes a step of recognizing a 3D digital code formed on at least one surface of the waste plastic with a terminal and classifying the waste plastic material by type, wherein information including the type of material is stored in the 3D digital code, and the waste plastic has a 3D digital code pattern formed three-dimensionally on at least one surface, and the open 3D digital code pattern and the plastic molded product are integrally formed.

[0043] 19. In the above 18 specific examples, the 3D digital code may be made of the same material as the plastic molded product and may be formed by injection molding of the plastic molded product.

[0044] 20. In the above 18 or 19 specific examples, the plastic molded product is a plastic molded product having an opening formed on at least one side, the opening through which a fluid including gas, liquid or sound can pass, and the opening includes the 3D digital code and can be recognized by a terminal.

[0045] 21. Another aspect of the present invention is a method for forming a 3D digital code pattern. The 3D digital code pattern forming method is a 3D digital code pattern forming method with improved injection properties, and the method includes a step of injection-molding a plastic molded product in which a 3D digital code pattern is formed three-dimensionally using a mold in which a pattern is formed to transfer the 3D digital code pattern, wherein the mold has a pattern portion provided such that cells forming the 3D digital code pattern include connecting cells having a dot-connection structure, and the 3D digital code pattern stores information including a type of material for classification and recycling of the plastic molded product, and the connecting cells satisfy the following equation 1:

[0046] [Formula 1]

[0047] d / t = 1.5~10

[0048] In the above equation 1, d is the width of the cell forming the 3D digital code pattern of the plastic molded product, and t is the height of the cell forming the 3D digital code pattern.

[0049] 22. In the above 21 specific examples, the 3D digital code may be made of the same material as the plastic molded product and may be formed integrally with the plastic molded product.

[0050] 23. In the above 21 or 22 specific examples, the t may be 1.0 mm or more.

[0051] 24. Another aspect of the present invention relates to a plastic molded product according to another specific example. The plastic molded product is characterized in that it has a 3D digital code pattern formed by the 3D digital code pattern forming method of the specific examples 21 to 23.

[0052]

[0053] The present invention embodies a 3D digital code as a part of a plastic part in three dimensions, and has excellent design freedom due to excellent variations in the depth (engraved / embossed) of the 3D digital code, brightness and color of the plastic, size and design of the code, and even if a part of the product is damaged, recycling information can be read by the digital code, so that it can be easily classified and recycled, and can be easily manufactured with a single injection molding without the need for subsequent processes such as labeling or perforation, and the 3D digital code can be applied to curved surfaces and large areas, so that product-related information can be contained while providing a design effect, and can contribute to closed-loop recycling and a circular economy by enabling recycling of high-purity waste plastic, and can have a digital code with excellent recognition rate regardless of color or pattern shape, and can achieve both recyclability and aesthetics by assigning a digital code to an opening through which sound or fluid passes, so that it can be environmentally friendly, and a plastic molded product and its product that can improve the injection property of a fine 3D code and at the same time enhance the recognition rate, as needed. The invention has the effect of obtaining a manufacturing method.

[0054]

[0055] Figures 1(a) to (d) are plastic molded products in which conventional digital codes are formed.

[0056] Figures 2(a) to 2(b) are plastic molded products according to one specific example of the present invention, and Figure 2(c) is a plastic molded product according to another specific example in which an opening is formed.

[0057] Figure 3 schematically illustrates a pattern of a 3D digital code according to a specific example of the present invention.

[0058] FIG. 4 illustrates a pattern of a 3D digital code according to depth according to another specific example of the present invention.

[0059] Figure 5 schematically illustrates a pattern of a 3D digital code according to another specific example of the present invention.

[0060] FIG. 6 (a) is a side perspective view of a molded product in which a 3D digital code according to another specific example of the present invention is formed by a combination of a perforation pattern and a positive / negative pattern, and (b) schematically illustrates a cross-section of the CC' plane of (a).

[0061] Figure 7 schematically illustrates a cross-section of a pattern according to one specific example of the present invention.

[0062] Figure 8 schematically illustrates a method for manufacturing a plastic molded product according to one specific example of the present invention.

[0063] Figure 9a schematically illustrates a cross-section of a mold according to one specific example of the present invention.

[0064] Figure 9b is a pattern portion of a mold according to another specific example of the present invention.

[0065] FIG. 10 illustrates a pattern of a 3D digital code according to color according to another specific example of the present invention.

[0066] Figure 11 schematically illustrates a cross-section of a plastic molded product according to another specific example of the present invention.

[0067] Figure 12 is a conceptual diagram showing a recovery method according to one specific example of the present invention.

[0068] Figure 13 illustrates closed-loop recycling of waste plastic according to one specific example of the present invention.

[0069] Figure 14 compares the conventional attached / printed 2D digital code method with the injection-molded 3D digital code method of the present invention.

[0070] Figure 15 schematically illustrates (a) a cross-section of the pattern before improvement and (b) a cross-section of the pattern after improvement.

[0071] Figure 16 (a) shows a pattern of a 3D digital code before improvement transferred to a plastic molded product according to one specific example, and (b) shows a pattern of a 3D digital code after improvement.

[0072] Figure 17 (a) shows a pattern of a 3D digital code of a mold before improvement according to a specific example, and (b) shows a pattern of a 3D digital code of a mold after improvement.

[0073] Figure 18 (a) shows a pattern of a 3D digital code before improvement transferred to a plastic molded product according to another specific example, and (b) shows a pattern of a 3D digital code after improvement.

[0074] Figure 19 (a) shows a pattern of a 3D digital code of a mold before improvement according to another specific example, and (b) shows a pattern of a 3D digital code of a mold after improvement.

[0075] Figure 20 (a) is a pattern of a 3D digital code transferred before improvement, and (b) is a pattern of a 3D digital code transferred after improvement.

[0076]

[0077] One perspective concerns plastic moldings.

[0078] FIG. 2(a) and FIG. 2(b) are plastic molded products (10) according to one specific example of the present invention, and FIG. 2(c) is a plastic molded product according to another specific example in which an opening is formed.

[0079] The above plastic molded product (10) has a 3D digital code (P) formed three-dimensionally on at least one surface.

[0080] In Fig. 2(c), the plastic molded product (10) has an opening (P) formed on at least one surface. The opening (P) allows a fluid including gas, liquid, or sound to pass through, and the opening includes a 3D digital code that can be recognized by a terminal. Specifically, the 3D digital code pattern is formed in an open shape, and the open 3D digital code pattern and the plastic molded product are formed integrally.

[0081] In Fig. 2(c), the opening is formed during injection molding of the plastic molded product. This eliminates the need for subsequent processes, such as separate laser processing or etching, significantly improving productivity. Furthermore, 3D digital codes can be applied to curved surfaces.

[0082] The above 3D digital code is made of the same material as the plastic molded product and is formed integrally with the plastic molded product. Therefore, no attachment or removal is required for 3D digital code labeling, and since it is made of the same material as the plastic molded product, it can be recycled in one go.

[0083] The above 3D digital code may be a QR code or a barcode. Fig. 2(a) illustrates a QR code as an example of a 3D digital code (P), and Fig. 2(b) illustrates a barcode as an example of a 3D digital code (P). The 3D digital code is formed simultaneously with the molded product by injection molding the plastic molded product. Accordingly, since separate laser processing or etching processes or other subsequent processes are unnecessary, not only can productivity be greatly improved, but also 3D digital codes can be assigned to curved surfaces.

[0084] The above 3D digital code can contain information about the material of the plastic molded product, such as its composition, composition ratio, color, and additives. In the past, plastics were classified according to the markings such as HDPE and PP indicated on the surface, and if the markings were damaged and could not be found or were not indicated, they had no choice but to be discarded and incinerated. However, the present invention can accurately classify all types of plastics, such as PET, PP, LDPE, PS, HDPE, PVC, PC, LDPE, PC-ABS, HPPS, acrylic resin, melanin resin, urea resin, epoxy resin, urethane resin, and silicone resin, through 3D digital code recognition, and can also provide information on its composition ratio, reinforcing material, color, and additives. Therefore, classification by material, composition, and additive is easy, and most discarded plastics can be recycled. For example, even for the same polycarbonate material, detailed classification is possible, such as whether it is fiber reinforced, whether it contains more than 50% glass fiber, whether it contains a flame retardant, and whether a matting agent is added. Plastics classified in this way can be recycled using a recycling process appropriate for each material / component. This drastically reduces energy and labor consumption during the sorting and recycling process, significantly reducing the amount of plastic waste, and ultimately achieving carbon neutrality.

[0085] The above 3D digital code pattern may have an engraved pattern, a raised pattern, or a perforated pattern. Fig. 3 (a) illustrates an engraved pattern, (b) illustrates an raised pattern, and (c) illustrates a perforated pattern. In one specific embodiment of the present invention, the entire 3D digital code may have an engraved pattern, a raised pattern, or a perforated pattern. In another specific embodiment of the present invention, the 3D digital code is formed by a combination of two or more types of an engraved pattern, a raised pattern, or a perforated pattern.

[0086] In Fig. 2(c), the opening may have a perforation pattern. In another specific embodiment of the present invention, the entire 3D digital code is formed by openings, and the entire code has a perforation pattern. In yet another specific embodiment of the present invention, the 3D digital code is formed by a combination of a perforation pattern and a positive / negative pattern.

[0087] In this case, the perforation pattern can be permeable to fluid or sound, while the positive / negative pattern is not permeable to fluid or sound and serves only to provide aesthetics.

[0088] As illustrated in (a) to (c) of FIG. 3, the 3D digital code has a thickness (t), and the thickness may be about 1.0 mm or more, preferably about 1.5 mm or more, for example, about 1.5 to about 5 mm. Within the above range, the digital code is easy to manufacture, and the digital code can be easily recognized. Conventionally, the thickness was in the micron unit because it was formed by processing such as laser or etching. In the present invention, since the thickness of the pattern is about 1.0 mm or more, the 3D digital code recognition rate does not decrease and no error occurs even after long-term use.

[0089] FIG. 4 illustrates a pattern of a 3D digital code according to depth according to another specific embodiment of the present invention. As illustrated in FIG. 4, the deeper the pattern, the clearer the pattern and the higher the recognition rate. When the thickness of the 3D digital code is approximately 0.5 mm, the code recognition rate may drop to approximately 80%, and when the thickness is at least approximately 1.0 mm or more, the code recognition rate can secure approximately 97% or more.

[0090] Figure 5 schematically illustrates a pattern of a 3D digital code according to another specific example of the present invention.

[0091] As illustrated in (a) and (b) of FIG. 5, the plastic molded product (10) may have a matte surface. In addition, as illustrated in (c) of FIG. 5, the plastic molded product (10) may have a comb-like pattern, and a 3D digital code may be formed on the comb-like pattern. In addition, as illustrated in (d) of FIG. 5, a 3D digital code may be formed in series to form a unique pattern. Although not illustrated, the plastic molded product itself may have a three-dimensional pattern, such as stripes, dots, or wood grain. When the plastic molded product has a three-dimensional pattern, the 3D digital code (P) may be formed on the three-dimensional pattern. In this way, even when the plastic molded product (10) has a three-dimensional pattern rather than a matte surface, the three-dimensional pattern and the 3D digital code may be formed simultaneously in a single injection mold.

[0092] The above 3D digital code (P) is made of the same material as the plastic molded product and is formed integrally with the plastic molded product. Therefore, no attachment or detachment is required for 3D digital code labeling, and since it is made of the same material as the plastic molded product, it can be recycled in one go.

[0093] FIG. 6(a) is a side perspective view of a molded product in which a 3D digital code according to another specific example of the present invention is formed by a combination of a perforation pattern and a relief / engraved pattern, and FIG. 6(b) schematically illustrates a cross-section of the CC' plane of FIG. 6(a). As illustrated, the 3D digital code can be formed by a combination of P1 in which a perforation pattern is formed and P2 in which an intaglio pattern is formed. The P1 portion in which the perforation pattern is formed has a thickness t1, and the P2 portion in which the intaglio pattern is formed has a thickness t2. t1 and t2 are about 1.0 mm or more, preferably about 1.5 mm or more, for example, about 1.5 to about 5 mm, and t1 > t2. In the drawing, P2 is formed as an intaglio pattern, but it may be formed as a relief pattern. In addition, the 3D digital code may be in the form of a 3D digital code or a barcode. A perforation pattern is an opening through which a fluid, including gas, liquid, or sound, can pass.

[0094] In specific examples, the opening can be applied as a speaker grill, a vent hole, an air purifier exhaust port, a humidifier exhaust port, a home appliance vent hole, a vacuum cleaner exhaust port, or a food packaging container exhaust port.

[0095] In addition, since the 3D digital code of the present invention is formed simultaneously with the injection molding of a plastic molded product, it can be formed on a curved surface and can impart a new aesthetic feel on its own.

[0096] Figure 7 schematically illustrates a cross-section of a pattern according to one specific embodiment of the present invention.

[0097] As illustrated, the 3D digital code has a thickness-wise pattern in the form of an oblique plane (P1). For example, the oblique plane (P1) may form an angle (θ) of about 5 to about 45 degrees from the thickness direction. In a specific example, the angle (θ) is about 10 to about 30 degrees, preferably about 15 to about 25 degrees. In the above range, the pattern is less likely to be damaged or broken, and the pattern recognition rate is excellent.

[0098] Additionally, the surface (W1) in contact with the mold bottom is smaller than the surface (W2) located on the top of the mold. In this case, the pattern is less likely to be damaged or broken, and the pattern recognition rate is excellent.

[0099] The above 3D digital code is not printed. Therefore, it does not contain ink. Furthermore, the 3D digital code is not formed through post-processing such as laser or etching, but is formed simultaneously with the injection molding process, making it economical and requiring no additional costs or energy consumption.

[0100] Such 3D digital code patterns can be formed on at least about 30%, at least about 50%, at least about 70%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 99%, or the entire surface of the plastic molded product. When the 3D digital code patterns are formed on at least about 50%, preferably at least about 70%, of the surface of the plastic molded product, even if part of the product is damaged, recycling information can be read by the digital code, so that the product can be easily classified and recycled.

[0101] For example, Fig. 2 illustrates a speaker as a plastic molded product, wherein one entire surface of the plastic molded product is formed with a 3D digital code (an open 3D digital code). As shown in Fig. 2, if the speaker grill itself is formed with a 3D digital code, the opening transmits information about the molded product as sound passes through, thereby facilitating its recycling.

[0102] In other specific examples, the front of a plastic molded product may be formed with a 3D digital code. For example, the front of a food packaging container may be formed with an open barcode, allowing for airflow to ensure freshness and distribution, and creating new designs.

[0103] In this way, since the 3D digital code is formed at approximately 30% or more, even if a portion of the plastic molded product is damaged or a broken piece is missing, the material can be easily identified and classified using the 3D digital code. Therefore, while previously broken plastic pieces were difficult to recycle and had to be discarded, the plastic molded product of the present invention can be easily recovered, significantly reducing environmental pollution.

[0104] The material of the above plastic molded product may be any recyclable resin, including but not limited to polyester, polyolefin, polystyrene, polyvinyl chloride, ABS, polycarbonate, and silicone resin. These materials may be used alone or in combination.

[0105] In addition, the above-mentioned plastic molded products include electronic product housings, food packaging, disposable product packaging, etc., and include all products to which recyclable plastics are applied. In this way, by linking the fact that perforated QR / Bar codes can be repeatedly patterned on the surface of the housing of electronic products (air purifiers, speakers, or TV parts with grilles or vent holes), a new function of resource recycling can be given to the pattern in addition to the existing purpose of vent holes or grilles, which is to dissipate air / sound / heat. In addition, if the QR code is repeatedly applied, it has the advantage of being recognizable even if some of the parts are damaged during the separation and sorting process.

[0106]

[0107] Another aspect of the present invention is a method for manufacturing a plastic molded product. The method comprises the steps of: injection molding molten plastic using a mold imprinted with a 3D digital code; and separating the injected plastic molded product from the mold.

[0108] Figure 8 schematically illustrates a method for manufacturing a plastic molded product according to one specific example of the present invention.

[0109] Specifically, it includes the steps of (a) preparing a mold (20) having a mold pattern portion (21) for a 3D digital code (P) engraved thereon, (b) injecting molten plastic (10a) into the mold (20) to form a plastic molded product (10) in which a 3D digital code (P) is formed three-dimensionally, and (c) separating the plastic molded product (10) from the mold (20). The plastic molded product (10) thus separated has a 3D digital code pattern formed three-dimensionally and / or openly on at least one surface, and the 3D digital code pattern and the plastic molded product are formed integrally.

[0110] Figure 9a schematically illustrates a cross-section of a mold (mold (20)) according to one specific example of the present invention.

[0111] As illustrated, a mold pattern portion (21) for a 3D digital code (P) is formed in the mold (20). The thickness (t) of the mold pattern portion (21) may be about 1.0 mm or more, preferably about 1.5 mm or more, for example, about 1.5 to about 5 mm. Within the above range, the digital code can be easily recognized.

[0112] The cross-section of the above mold pattern portion (21) is tapered, and for example, the width (d2) of the lower portion of the mold pattern is larger than the width (d1) of the upper portion of the pattern. When designed in this manner, separation of the mold and the molded product is easy, and the recognition of the formed 3D digital code is also excellent.

[0113] Figure 9b illustrates a pattern portion of a mold according to another specific example of the present invention. As illustrated, the mold pattern portion may have an engraved, raised, or perforated shape, and a plastic molded product manufactured using the mold pattern portion has the mold pattern pattern transferred through injection molding.

[0114] Figure 10 illustrates a pattern of a 3D digital code according to color according to another specific embodiment of the present invention. As illustrated, a plastic molded product may have various colors, and a 3D digital code can be formed regardless of the color of the plastic molded product. However, if the color of the plastic molded product is dark, such as black, the recognition of the 3D digital code tends to be somewhat poor. According to the present invention, even if the plastic color is dark, such as black, a recognition rate of approximately 97% or higher can be secured, as will be described in detail below.

[0115]

[0116] Another aspect of the present invention relates to a plastic molded article according to another specific example.

[0117] Figure 11 schematically illustrates a cross-section of a plastic molded product (10) according to another specific example of the present invention.

[0118] The above plastic molded product (10) has a 3D digital code (P) formed three-dimensionally on at least one surface, and the 3D digital code includes a concave portion (12) and a protruding portion (11), and is formed by injection molding of the plastic molded product. Either the concave portion (12) or the protruding portion (11) is characterized in that it has a diffuse reflection surface (13) or a glossy surface (13). Since it has the diffuse reflection surface or the glossy surface, it can have an excellent recognition rate regardless of the color or pattern shape.

[0119] The above 3D digital code (P) is made of the same material as the plastic molded product and is formed integrally with the plastic molded product. The 3D digital code may be a QR code or a barcode. Fig. 2(a) illustrates a QR code as an example of the 3D digital code (P), and Fig. 2(b) illustrates a barcode as an example of the 3D digital code (P). The 3D digital code is formed simultaneously with the molded product by injection of the plastic molded product. Accordingly, since a separate laser processing or etching process or other subsequent process is unnecessary, not only can productivity be greatly improved, but also a 3D digital code can be assigned to a curved surface.

[0120] The above 3D digital code can contain information about the material of the plastic molded product, such as its composition, composition ratio, color, and additives. In the past, plastics were classified according to the markings such as HDPE and PP indicated on the surface, and if the markings were damaged and could not be found or were not indicated, they had no choice but to be discarded and incinerated. However, the present invention can accurately classify all types of plastics, such as PET, PP, LDPE, PS, HDPE, PVC, PC, LDPE, PC-ABS, HPPS, acrylic resin, melanin resin, urea resin, epoxy resin, urethane resin, and silicone resin, through 3D digital code recognition, and can also provide information on its composition ratio, reinforcing material, color, and additives. Therefore, classification by material, composition, and additive is easy, and most discarded plastics can be recycled. For example, even for the same polycarbonate material, detailed classification is possible, such as whether it is fiber reinforced, whether it contains more than 50% glass fiber, whether it contains a flame retardant, and whether a matting agent is added. Plastics classified in this way can be recycled using a recycling process appropriate for each material / component. This drastically reduces energy and labor consumption during the sorting and recycling process, significantly reducing the amount of plastic waste, and ultimately achieving carbon neutrality.

[0121] The above 3D digital code pattern may have an engraved pattern, a raised pattern, or a perforated pattern. Fig. 3 (a) shows an engraved pattern, (b) shows a raised pattern, and (c) shows a perforated pattern. In one specific embodiment of the present invention, the entire 3D digital code may have an engraved pattern, a raised pattern, or a perforated pattern. In another specific embodiment of the present invention, the 3D digital code is formed by a combination of two or more types of an engraved pattern, a raised pattern, or a perforated pattern.

[0122] The above 3D digital code has a thickness (t), and the thickness may be about 1.0 mm or more, preferably about 1.5 mm or more, for example, about 1.5 to about 5 mm. Conventionally, the thickness was in the order of microns due to formation by processing such as laser or etching. In the present invention, since the thickness of the pattern is about 1.0 mm or more, the 3D digital code recognition rate does not decrease and no errors occur even after long-term use.

[0123] FIG. 4 illustrates a pattern of a 3D digital code according to depth according to another specific embodiment of the present invention. As illustrated in FIG. 4, the deeper the pattern, the clearer the pattern and the higher the recognition rate. When the thickness of the 3D digital code is about 0.5 mm, the code recognition rate may drop to about 80%, and when the thickness is at least about 1.0 mm or more, the code recognition rate can secure about 97% or more.

[0124] Figure 7 schematically illustrates a cross-section of a pattern according to one specific embodiment of the present invention.

[0125] As illustrated, the 3D digital code has a thickness-wise pattern in the form of an oblique plane (P1). For example, the oblique plane (P1) may form an angle (θ) of about 5 to about 45 degrees from the thickness direction. In a specific example, the angle (θ) is about 10 to about 30 degrees, preferably about 15 to about 25 degrees. In the above range, the pattern is less likely to be damaged or broken, and the pattern recognition rate is excellent.

[0126] Additionally, the surface (W1) in contact with the mold bottom is smaller than the surface (W2) located on the top of the mold. In this case, the pattern is less likely to be damaged or broken, and the pattern recognition rate is excellent.

[0127] The above 3D digital code is not printed. Therefore, it does not contain ink. Furthermore, the 3D digital code is not formed through post-processing such as laser or etching, but is formed simultaneously with the injection molding process, making it economical and requiring no additional costs or energy consumption.

[0128] The above 3D digital code pattern may be formed on at least about 30%, at least about 50%, at least about 70%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 99%, or the entire surface of the plastic molded product. Fig. 2 shows a case where the 3D digital code is formed on the entire surface of one side of the plastic molded product. In another specific example, the entire surface of the plastic molded product may be formed with the 3D digital code.

[0129] Because the 3D digital code is formed at approximately 30% or more of the plastic molded product, even if part of the plastic molded product is damaged or a broken piece is missing, the material can be easily identified and classified using the 3D digital code. Therefore, while previously broken plastic pieces were difficult to recycle, the plastic molded product of the present invention can be easily recovered.

[0130] The material of the above plastic molded product can be any recyclable resin, including but not limited to polyester, polyolefin, polystyrene, polyvinyl chloride, ABS, polycarbonate, and silicone resin. These materials, either singly or in a blend, can also be used.

[0131] In addition, the above plastic molded products include housings for electronic products, food packaging, disposable product packaging, etc., and include all products to which recyclable plastics are applied.

[0132] The above-mentioned diffuse reflection surface (13) or glossy surface (13) can be formed by surface treatment. For example, the diffuse reflection or glossy surface treatment can be achieved by surface treating the mold by physically or chemically etching the mold, and then injection molding using the surface-treated mold, thereby imprinting the diffuse reflection or glossy surface. By using a mold surface-treated in this way, a diffuse reflection or glossy surface can be obtained through injection molding alone without a separate post-treatment process.

[0133] The method for manufacturing the above plastic molded product can be manufactured by injection molding according to the method illustrated in FIG. 8. Specifically, the method includes the steps of (a) preparing a mold (20) having a 3D digital code (P) engraved thereon, (b) injecting molten plastic (10a) into the mold (20) to form a plastic molded product (10) in which the 3D digital code (P) is formed three-dimensionally, and (c) separating the plastic molded product (10) from the mold (20). In this way, the separated plastic molded product (10) has a 3D digital code pattern formed three-dimensionally on at least one surface, and the 3D digital code pattern includes a concave portion and a protruding portion. Thereafter, the method includes the step of (d) performing a diffuse reflection or glossy surface treatment on either the concave portion or the protruding portion. In this way, since either the concave portion (12) or the protruding portion (11) has a diffuse reflection or glossy surface, it is possible to have an excellent recognition rate regardless of the color or pattern shape of the plastic molded product.

[0134] The above mold has a mold pattern portion (21) formed as shown in the mold cross-section of Fig. 9a, and further, the cross-section of the mold pattern portion (21) may be tapered.

[0135]

[0136] Another aspect of the present invention is a method for recycling the above plastic molded product.

[0137] The above method includes a step of recognizing a 3D digital code formed on at least one surface of waste plastic with a terminal and classifying the waste plastic material by type.

[0138] In general, waste plastics can be damaged during the collection process, and broken pieces of waste plastic cannot be recycled because it is difficult to classify them because the product material is unknown. However, since the present invention forms a 3D digital code on the waste plastic material itself, even broken pieces can be recognized by the terminal, and the recognized parts can be classified and recycled. In this case, the 3D digital code stores information including the type of material. Information that can be stored includes, but is not limited to, the type of material such as PET, PP, LDPE, PS, HDPE, PVC, OTHER, the color of the material, the manufacturer, and additives.

[0139]

[0140] Another aspect of the present invention is a method for recovering waste plastic using a 3D digital code.

[0141] Figure 12 is a conceptual diagram showing a recovery method according to one specific example of the present invention.

[0142] As illustrated in Fig. 12, when a 3D digital code formed on at least one surface of waste plastic (15) discarded after using a plastic molded product (10) is recognized by a terminal (30), information on the material of the waste plastic, such as components, component ratio, color, additives, etc., can be obtained and classified by type. For example, by recognizing the 3D digital code, not only can all types of plastics such as PET, PP, LDPE, PS, HDPE, PVC, PC, LDPE, PC-ABS, HPPS, acrylic resin, melanin resin, urea resin, epoxy resin, urethane resin, silicone resin, etc. be accurately classified, but also information on component ratio, reinforcing material, color, additives, etc. can be known, so classification by material, component, and additive is easy, and most discarded plastics can be recycled. For example, even for the same polycarbonate material, detailed classification is possible, such as whether or not it is fiber reinforced, whether or not it contains more than 50% glass fiber, whether or not it contains a flame retardant, and whether or not a matting agent is added. Plastics classified in this way can be recycled using appropriate recycling processes. This can significantly reduce energy and labor consumption during the sorting and recycling process, significantly reducing the amount of plastic waste, and ultimately achieving carbon neutrality.

[0143] The above method includes a step of classifying waste plastic material by type by recognizing a 3D digital code formed on at least one side of waste plastic (15) with a terminal (30). The waste plastic includes a 3D digital code on at least one side and can be recognized by the terminal.

[0144] In a specific example, the waste plastic is formed by the method for manufacturing the plastic molded product. For example, it may be a speaker, an air purifier, a humidifier, a home appliance housing, a vacuum cleaner, or food packaging material.

[0145] In general, waste plastics can be damaged during the collection process, and broken pieces of waste plastic cannot be recycled because it is difficult to classify them because the product material is unknown. However, since the present invention forms a 3D digital code on the waste plastic material itself, even broken pieces can be recognized by the terminal, and the recognized parts can be classified and recycled. In this case, the 3D digital code stores information including the type of material. Information that can be stored includes, but is not limited to, the type of material such as PET, PP, LDPE, PS, HDPE, PVC, OTHER, the color of the material, the manufacturer, and additives.

[0146] The above-mentioned waste plastic has a 3D digital code pattern formed on at least one surface, and the 3D digital code pattern and the plastic molded product are formed integrally. For example, the 3D digital code pattern may be formed on about 30% or more, about 50% or more, about 70% or more, about 80% or more, about 85% or more, about 90% or more, about 95% or more, about 99% or more, or the entire surface of the plastic molded product.

[0147] Since the above 3D digital code is formed simultaneously during injection molding of the plastic molded product, it is made of the same material as the plastic molded product and is formed integrally with the plastic molded product.

[0148] In a specific example, the 3D digital code may be a QR code or a barcode.

[0149] The above 3D digital code pattern may have an engraved pattern, a raised pattern, or a perforated pattern. In another specific embodiment of the present invention, the 3D digital code is formed by a combination of a perforated pattern and a raised / engraved pattern.

[0150] The above 3D digital code has a thickness (t), and the thickness may be about 1.0 mm or more, preferably about 1.5 mm or more, for example, about 1.5 to about 5 mm. The digital code can be easily recognized within the above range. Conventionally, the digital code was formed by processing such as laser or etching, and the thickness was in the micron unit. In the present invention, since the thickness of the pattern is about 1.0 mm or more, the 3D digital code recognition rate does not decrease and no errors occur even after long-term use.

[0151] FIG. 13 illustrates closed-loop recycling of waste plastic according to one specific example of the present invention, and FIG. 14 compares a conventional attached / printed 2D digital code method with an injection-molded 3D digital code method of the present invention. As illustrated in FIG. 13, when a consumer uses and discards plastic, a waste plastic management company collects the waste plastic, separates the label or sticker, and then classifies it by type according to the product material indicated on a portion of the waste plastic. In the past, the work of separating the label or sticker was inevitably involved, which wasted manpower and energy and could be a major cause of environmental pollution. In addition, when the waste plastic was damaged, the material of the product could not be identified, so it could not be recycled and was discarded as is. Since the 3D digital code of the present invention is formed by injection molding rather than printing, there is no need to remove the sticker or adhesive. In particular, the opening itself can be formed with an open 3D digital code pattern, providing not only practical benefits like ventilation but also design effects while also containing product-related information. Furthermore, since 3D digital codes can be applied to large areas, even if the product is damaged, it can be easily sorted and recycled without disposal. Consequently, as illustrated in Figure 13, it can also contribute to a circular economy.

[0152] In addition, as illustrated in Fig. 14, the conventional method essentially involved a sticker and adhesive removal process, but when applying the plastic molded product of the present invention, the sticker or adhesive removal process is unnecessary because product information can be included in the product itself through injection.

[0153]

[0154] In this specification, a 'cell' is a unit structure forming a 3D digital code (e.g., a 3D digital code) pattern and having a protruding or concave shape.

[0155] In this specification, a 'dot' is one of the cell shapes and has a square or circular shape when viewed in the front direction.

[0156] When manufacturing a plastic molded product of the present invention, the single-cell portion of the 3D digital code may be difficult to inject, which can lower recognition. Therefore, it is necessary to improve injection moldability to increase the recognition rate of the final molded product.

[0157] Another aspect of the present invention relates to a method for forming a 3D digital code pattern with improved injection properties.

[0158] The method comprises a step of injection-molding a plastic molded product having a three-dimensionally formed 3D digital code pattern using a mold having a pattern formed to transfer a 3D digital code pattern. The mold is characterized in that a pattern portion is provided such that cells forming the 3D digital code pattern include connecting cells having a dot-connected structure, the 3D digital code pattern stores information including a type of material for classification and recycling of the plastic molded product, and the connecting cells satisfy the following equation 1.

[0159] [Formula 1]

[0160] d / t = 1.5~10

[0161] In the above equation 1, d is the width of the cell forming the 3D digital code pattern of the plastic molded product, and t is the height of the cell forming the 3D digital code pattern.

[0162] Fig. 15 schematically illustrates (a) a cross-section of a pattern before improvement and (b) a cross-section of a pattern after improvement, (c) is a front view of the pattern (a), and (d) is a front view of the pattern (b). As illustrated, the cross-section (P1) of the pattern before improvement (a) has d / t of 1 or less. On the other hand, the pattern (P2) improved by the present invention has a dot-connected structure in which cells are connected to each other, and the value according to Equation 1 may have a range of 1.5 to 10, preferably 2 to 9, and more preferably 2.5 to 7. In the above range, there is no pattern damage, and the pattern recognition rate is excellent.

[0163] In addition, the pattern having such a dot connection structure is about 50% or more, preferably about 75% or more, and more preferably about 80% or more of the entire 3D digital code pattern. (c) and (d) of Fig. 15 are the shapes of the pattern as viewed from the front, and a is the length of the cell. In one specific example, d / a may be 1.5 to 10.

[0164] The mold for forming the above pattern is a mold having a pattern formed to transfer a 3D digital code pattern, the mold including a receiving portion for receiving molten plastic; and a pattern portion for transferring the 3D digital code pattern to the molten plastic, the pattern portion being provided such that the cells forming the 3D digital code pattern include connecting cells having a dot-connected structure.

[0165] Fig. 16(a) shows a pattern of a 3D digital code before improvement transferred to a plastic molded product according to one specific example, and Fig. 16(b) shows a pattern of a 3D digital code after improvement. Fig. 17(a) shows a pattern of a 3D digital code of a mold before improvement according to another specific example, and Fig. 17(b) shows a pattern of a 3D digital code of a mold after improvement.

[0166] As illustrated, the patterns of the 3D digital code before improvement in FIGS. 16 (a) and 18 (a) are formed with fine cells each formed independently. In this case, when separating the plastic molded product from the mold, there is a high possibility that the fine cell shape will be damaged, which may cause problems in recognition. In the present invention, the cells forming the 3D digital code pattern include connecting cells having a dot-connection structure, thereby preventing damage to the pattern. The patterns of the 3D digital code after improvement in FIGS. 16 (b) and 18 (b) are characterized in that the cells forming the 3D digital code pattern form connecting cells having a dot-connection structure.

[0167] In specific examples, the connecting cells are configured to account for at least about 50% of the total cells, preferably at least about 75%, and more preferably at least about 80%. Within this range, damage to the cell shape during manufacturing is prevented, and the phenomenon of dust accumulating between cells even after long-term use is minimized.

[0168] Fig. 19 (a) shows a pattern of a 3D digital code of a mold before improvement according to another specific example, and Fig. 19 (b) shows a pattern of a 3D digital code of a mold after improvement.

[0169] Figure 20 (a) is a pattern of a 3D digital code transferred before improvement, and Figure 20 (b) is a pattern of a 3D digital code transferred after improvement.

[0170] Additionally, the shape of the mold can be modified to further improve the injection properties.

[0171]

[0172] Simple modifications or changes of the present invention can be easily implemented by a person having ordinary skill in the art, and all such modifications or changes can be considered to be included in the scope of the present invention.

Claims

1. A plastic molded product with a 3D digital code pattern formed three-dimensionally on at least one side. The above 3D digital code stores information including the type of material for classification and recycling of the plastic molded product, and is formed by injection of the plastic molded product. A plastic molded product characterized in that the above 3D digital code is made of the same material as the plastic molded product and is formed integrally with the plastic molded product.

2. A plastic molded product according to claim 1, characterized in that the 3D digital code is a QR code or a barcode.

3. A plastic molded product according to claim 1 or 2, characterized in that the 3D digital code pattern has an engraved pattern, a relief pattern, or a perforated pattern.

4. A plastic molded product according to any one of claims 1 to 3, characterized in that the 3D digital code has a thickness, and the thickness is about 1.0 mm or more.

5. A plastic molded product according to any one of claims 1 to 4, characterized in that the 3D digital code pattern is formed on about 30% or more of the surface of the plastic molded product.

6. A plastic molded product according to any one of claims 1 to 5, characterized in that the 3D digital code pattern is formed by double injection.

7. A plastic molded product according to any one of claims 1 to 6, wherein the plastic molded product is a plastic molded product having an opening formed on at least one side, wherein the opening allows a fluid including gas, liquid or sound to pass through, and the opening includes the 3D digital code and is characterized in that it can be recognized by a terminal.

8. A plastic molded product according to claim 7, characterized in that the opening includes a speaker grill, a vent hole, an air purifier exhaust port, a humidifier exhaust port, a home appliance vent hole, a vacuum cleaner exhaust port, or a food packaging container exhaust port.

9. A step of injection molding molten plastic using a mold engraved with a 3D digital code; and A step of separating the above-mentioned injected plastic molded product and the mold; A method for manufacturing a plastic molded product, wherein the 3D digital code stores information including the type of material for classification and recycling of the plastic molded product.

10. A method for manufacturing a plastic molded product in claim 9, characterized in that the plastic molded product has a 3D digital code pattern formed three-dimensionally on at least one surface.

11. A plastic molded product according to claim 9 or 10, characterized in that the plastic molded product has an opening formed on at least one side, the opening allows a fluid including gas, liquid or sound to pass through, and the opening includes a 3D digital code and can be recognized by a terminal.

12. A method for manufacturing a plastic molded product according to any one of claims 9 to 11, wherein the plastic molded product has a 3D digital code pattern formed in an open manner on at least one surface, and the open 3D digital code pattern and the plastic molded product are formed integrally.

13. A method for forming a 3D digital code pattern with improved injection properties. The method comprises a step of injection molding a plastic molded product in which a 3D digital code pattern is formed in three dimensions using a mold in which a pattern is formed to transfer the 3D digital code pattern, The above mold is provided with a pattern portion such that the cells forming the 3D digital code pattern include connecting cells having a dot-connected structure, The above 3D digital code pattern stores information including the type of material for classification and recycling of the plastic molded product. The above connecting cell is characterized by a 3D digital code pattern forming method satisfying the following equation 1: [Formula 1] d / t = 1.5~10 In the above equation 1, d is the width of a cell forming a 3D digital code pattern of a plastic molded product, and t is the height of a cell forming a 3D digital code pattern.

14. A method for forming a 3D digital code pattern, characterized in that in the 13th paragraph, the 3D digital code is made of the same material as the plastic molded product and is formed integrally with the plastic molded product.

15. A method for forming a 3D digital code pattern according to claim 13 or 14, characterized in that t is 1.0 mm or more.

16. A plastic molded product characterized by having a 3D digital code pattern formed by the 3D digital code pattern forming method of any one of claims 13 to 15.

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