TWI911962B - Improvement of the manufacturing process of biodegradable bottle caps - Google Patents

Abstract

An improved biodegradable bottle cap production process, which is made by mixing plant fiber powder, starch, natural binder, water-soluble polymer glue, antibacterial agent, coupling agent, softener and lubricant in a certain proportion to make raw materials After pelletizing, the raw material pellets are dried and put into the barrel of the injection molding machine. The raw material pellets are kneaded at high temperature by the screw of the machine to a molten state and then filled and injected into the mold. The mold is equipped with several bottle cap mold cavities. , the fiber raw material is filled into the bottle cap mold cavity, and after the bottle cap threads in the mold cavity are shaped and cooled, the finished bottle cap is demoulded and taken out.

Description

Improved manufacturing process for biodegradable bottle caps

This creation pertains to the production and manufacturing of bottle caps, specifically referring to the composition of raw material particles and the manufacturing method of bottle caps made from biodegradable raw materials.

Note: Regarding the research and production of biodegradable raw material granule formulations, the applicant's previous invention was Patent Application No. 108102795, which discloses a composition of biodegradable plant fiber raw materials and its manufacturing method. The patent application discloses a raw material granule made from plant fiber, the formulation of which includes: 40-60% plant fiber powder, 20-30% starch, 10-20% starch-fermented plant gum powder, 5-10% water-soluble polymer, and 3-5% cellulose. The above formulation is heated and mixed into several strips, and then the strips are cut into granules by a cutting unit to produce raw material granules. Subsequently, the applicant filed application number 110105195 "Composition of plant fiber raw material granules and its application in fiber bottle molding method" and CN114940831 "Plant fiber raw material granules" Chinese patent application. While patent application number 110105195 discloses a technique for molding bottles and cans using molds, and its specification mentions that "when raw material granules are used as raw materials for, for example, injection molding machines or straw molding equipment, the injected or extruded products can have excellent tensile strength, toughness and bonding strength after the raw material granules are heated, and can be processed into products that meet the usage requirements," the bottle and can molding technique uses gas to blow heated raw material strips into shape, which is not suitable for molding threaded bottle caps. Furthermore, because bottle caps have threads, although conventional raw material granule components have sufficient tensile strength and toughness, they lack flexibility, and there is a need to improve this. Secondly, the Chinese patent CN114940831 discloses the use of bamboo vinegar, but the function of this bamboo vinegar is to decompose pesticide residues in plant fibers. Furthermore, the inventor of this case has five other prior patents disclosing different raw material granule formulations, namely: Application No. 110105196 "Method for forming fiber bags", Application No. 111102324 "Composition and manufacturing method of plant fiber strips for 3D printing", Application No. 111148738 "Composition and process of biodegradable tongue depressor", Application No. 112133948 "Improved manufacturing method of biodegradable single-piece bags", and Application No. 111127238 "Improved composition of biodegradable raw material granules".

The fiber granule formulations disclosed in the aforementioned customary patents are largely similar, mainly consisting of 41-59% plant fiber powder, 21-29% starch, and 8-28% natural binder. This natural binder is made by adding dicarboxylic acid and fermentation bacteria to starch. Water-soluble polymers (6-12%) are the main raw material, with selective addition of 3-5% modifier, 0.01-0.2% lubricant, 3-5% coupling agent, and 3-5% cellulose. After being made into granules, these granules can be manufactured into fiber bags, pressure plates, one-piece bags, and other products using specialized machinery, replacing plastic products.

Secondly, even though the global trend of reducing plastic use is becoming increasingly popular, plastics, which are convenient, easy to use, and low in manufacturing cost, are still the main material in modern economic society. The annual production of bottle caps alone reaches billions. Therefore, how to produce bottle caps using biodegradable materials has become a direction that the applicant has considered. In the applicant's previous customary invention, patent application No. 108102795, on the composition of biodegradable plant fiber raw materials and its manufacturing method, it was disclosed that when fiber powder is mixed at a high speed of 600-1200 RPM, 2-5% bamboo vinegar can be added, so that the bamboo vinegar can penetrate into the capillaries of the fiber during high-speed rotation to decompose residual pesticides. The bamboo vinegar used in this step breaks down pesticide residues in the plant fibers, after which the bamboo vinegar becomes ineffective in subsequent steps.

Furthermore, regarding prior patent applications for bottle cap production, Chinese application No. 202111266238.5, concerning a cosmetic bottle cap made of ABS modified plastic and its preparation method, mentions that antibacterial herbal extracts, such as aloe vera extract, tulip extract, or silver ions, can be added to the raw materials as antibacterial agents. However, this prior invention uses ABS modified plastic as a raw material, and therefore cannot be biodegradable. Another Chinese application, No. 202011146046... .6 A patent application for a biodegradable plastic bottle cap and its preparation method discloses the following preparation method: Step 1) Preparation of plasticized starch, wherein modified starch and a polyol are heated and plasticized, wherein the polyol is glycerol, to obtain glycerol plasticized starch; Step 2) Blending the obtained glycerol plasticized starch with polybutylene succinate to obtain starch/PBS material. Step 3): Mix polylactic acid, starch/PBS material, additives, coupling agent, dispersant, solubilizer, and reinforcing agent evenly according to the formula ratio to obtain a mixture; Step 4): Extrude the mixture through a twin-screw extruder, with the extruder head temperature being a gradient temperature; Step 5): Inject the prepared composite material through an injection molding machine to obtain bottle caps. Although this application uses biodegradable raw materials, the polylactic acid used cannot be decomposed by soil or water under normal conditions, and is not the optimal biodegradable bottle cap, requiring improvement. In view of this, the creator has conducted in-depth research on the aforementioned problems of habitual creation and, through years of experience in the research and development and manufacturing of related industries, actively sought solutions. After long-term efforts in research and development, the creator has finally successfully developed the "Biodegradable Bottle Cap Manufacturing Process Improvement" to improve the problems of habitual creation.

The main purpose of this invention is to provide an "improved biodegradable bottle cap manufacturing process" that enables bottle caps to be made from waste plant fiber raw materials mixed with starch, thereby reducing the environmental damage caused by plastic products.

To achieve the aforementioned creative objective, this invention, "Improved Manufacturing Process for Biodegradable Bottle Caps," includes the following process: A. Obtaining raw material granules, the components of which include: 41.5–57.8% plant fiber powder, 22.3–28.5% starch, 9.5–26% natural binder (made from starch with added dicarboxylic acid and fermentation bacteria), 6–9.8% water-soluble polymer, and 0.01–0.3% antibacterial agent. The mixture contains 3.2-5.8% of a coupling agent, 1-4% of a softener, and 0.02-0.18% of a lubricant; wherein the natural adhesive can be dried into powder, and its bacterial strain can be Aspergillus, yeast, lactic acid bacteria, or acetic acid bacteria; the water-soluble polymer can be carboxymethyl starch or acetate starch; the antibacterial agent can be one of nano-silver or antibacterial enzyme; and the lubricant can be primary amide, secondary amide, or ethylene distearate amide. B. Raw material particle drying: The raw material particles are placed in a hot dryer for drying to reduce the moisture content. C. Raw material particle heating: The raw material particles are placed from the barrel of the injection molding machine into the feed tube and molten using a screw at high temperature. D. Injection molding: Molten fiber material is injected into a mold containing several cap cavities, into which the fiber material fills. E. Bottle cap thread setting: The thread block in the mold is removed, setting the threads of the bottle cap. F. Demolding: After the fiber material forming the bottle cap in the cavity cools and sets, the bottle cap is demolded and removed. In this way, raw material granules are made from pure natural plant materials, and then these granules are used in an injection molding machine to produce bottle caps that are biodegradable by soil and water. Regarding the techniques, methods, and effects employed in this work, a preferred embodiment is provided below with detailed explanations and accompanying diagrams. It is believed that the aforementioned purpose, structure, and features of this work can be understood in depth and in detail from this explanation.

Please refer to Figures 1 to 6. This invention, "Improved Manufacturing Process for Biodegradable Bottle Caps," uses biodegradable plant-based raw materials to formulate raw material granules for the production of bottle caps (70). The overall manufacturing process includes:

A. Obtain raw material granules, the composition of which includes: 41.5-57.8% plant fiber powder, 22.3-28.5% starch, 9.5-26% natural binder (made from starch with added dicarboxylic acid and fermentation bacteria), 6-9.8% water-soluble polymer, 0.01-0.3% antibacterial agent, 3.2-5.8% coupling agent, 1-4% softener, and 0.02-0.18% lubricant, wherein:

This plant fiber powder uses the stems, bark, leaves, or fruit peels of natural plants as fiber raw materials. After crushing and drying, it is processed into powder with a moisture content of less than 20% and a particle size of approximately 200-400 mesh or more.

Starch is a high-molecular-weight carbohydrate stored in plants. It can be broken down into components such as glucose and maltose. It can be derived from the seeds (such as ginkgo, chestnut, peanut, pea, mung bean, red bean, etc.), fruits (such as wild oat, Job's tears, etc.), stems (such as potato, konjac, pumpkin, etc.), leaves, and roots (such as sweet potato, cassava, etc.) of plants such as ginkgo, bamboo, wheat, potato, corn, sweet potato, cassava, lotus root, rice, algae, and beans.

This natural binder is produced by fermenting a mixture of starch, microorganisms, and dicarboxylic acid. The starch molecule structure is modified, transforming the starch, which initially lacks significant polymeric viscosity after heating and gelatinization, into a more readily polymerizable material, thus greatly enhancing its cohesive strength. This allows for long-term polymerization of starch and plant fiber powder. The starch used can be derived from seeds, fruits, roots, stems, or leaves of plants such as wheat, potatoes, corn, sweet potatoes, cassava, lotus root, rice, or algae. The added dicarboxylic acid refers to an organic compound containing two carboxyl functional groups, and can be oxalic acid, glutaric acid, octanoic acid, azelaic acid, sebacic acid, or undecanoic acid. The fermentation microorganisms used can be Aspergillus, yeast, lactic acid bacteria, or acetic acid bacteria. After the above ingredients have been mixed and fermented, they are dried, ground into powder, and then stored and used in the future.

This water-soluble polymer is used to adjust the viscosity of the natural adhesive. It can be extracted from natural plant materials, such as starches, cellulose, or plant gums, or it can be a chemically modified natural polymer, such as carboxymethyl starch or starch acetate. Alternatively, it can be a synthetic polymer, including polymeric resins and condensed resins, such as polyacrylamide (PAM), hydrolyzed polyacrylamide (HPAM), and polyvinylpyrrolidone (PVP).

The antibacterial agent can be one or a combination of nano silver or antibacterial enzymes. When the raw material particles are made into bottle caps, the antibacterial agent can be used to prevent bacteria from adhering to the plant fibers.

This coupling agent is a multi-purpose coupling agent that acts as a bridge between organic and inorganic substances through a chemical reaction, and can increase the strength, toughness and multi-directional viscosity of the polymerized starch and plant fiber powder by this natural adhesive.

The softener can be an ester-based quaternary ammonium salt, used to soften plant fibers. When the raw material granules are heated and injection molded into bottle caps, it can improve the tightness of the raw material in the mold and ensure the structural stability of the bottle cap threads during molding.

The lubricant may be a primary amide, a secondary amide, or ethylene distearate amide, used to increase the lubrication of these raw materials during mixing, processing, and transportation.

After obtaining the above raw materials, the fiber powder is placed in a first mixer (11) for 10-30 minutes and mixed at a high speed of 600-1200 RPM at 40-60°C to soften the fiber powder. Then, the starch and coupling agent are placed in a second mixer (12) for 10-20 minutes and mixed at a high speed of 600-1200 RPM to activate the flowability of the powder particles. The natural binder and water-soluble polymer are then mixed in a third mixer (13) at a speed of about 2400 RPM for 10-40 minutes to achieve a viscous state. The fiber powder, starch, natural binder, antibacterial agent and lubricant mentioned above are then mixed and stirred in the fourth mixer (14) for 10 to 40 minutes to form a comprehensive raw material. To further explain, when the antibacterial agent is mixed and stirred with the fiber powder, starch and natural binder, the antibacterial agent is coated on the outer surface of the fiber powder and starch, thus achieving the antibacterial effect.

Next, the composite raw material is placed in a molding device (20). The molding device (20) has an inlet (21) at one end and an outlet (22) at the other end. The inlet (21) allows the composite raw material to be poured in, while the outlet (22) is provided with a molding extrusion plate (23). The extrusion plate (23) has several through holes (231). A conveying unit (24) is provided between the inlet (21) and the outlet (22). The conveying unit (24) can rotate, stir, and convey the composite raw material from the inlet (21) to the outlet (22) while heating it, so that it passes through the extrusion plate (23) and is extruded outward to form several long strips of raw material.

Secondly, the conveying unit (24) can be composed of two power screws (25), each of which can be composed of four conveying rods (251, 252, 253, 254) in sections. Each conveying rod (251, 252, 253, 254) has a blade (255) on its outer edge. The blade (255) of the first conveying rod (251) located at the feed inlet (21) is larger than the blades (255) of the other conveying rods (252, 253, 254). The blade (255) of the fourth conveying rod (254) located at the discharge outlet (22) is larger than the blade (255) of the other conveying rods (252, 253, 254). The size of the blade (255) is smaller than that of the blades (255) of the other conveyor bars (251, 252, 253). That is, the blades (255) of the outer edge of the conveyor bars (251, 252, 253, 254) gradually decrease in size from the inlet (21) to the outlet (22). The temperature of each conveyor bar (251, 252, 253, 254) is controlled between 140 and 180°C using different temperature controllers (not shown in the figure). Furthermore, the forming device (20) is provided with several exhaust pipes (26) corresponding to the positions of the first and second conveying rods (251, 252). These exhaust pipes (26) are connected to a vacuum machine (27) so that when the first and second conveying rods (251, 252) stir and convey the composite material, the moisture and water vapor contained therein can be discharged outward through these exhaust pipes (26). In this way, when the conveying unit (24) conveys the composite material, the composite material is first stirred evenly by the first and second conveying rods (251, 252), and then the composite material is gradually extruded outward through the third and fourth conveying rods (253, 254) to form a long strip of material.

The raw material strips are first cooled down by the first cooling system (30), and then the cutting unit (40) cuts the raw material strips into granular raw material particles. The first cooling system (30) includes a conveying platform (31), a power unit (32) located at the end of the conveying platform (31), and several fans (33) located above the conveying platform (31). The conveying platform (31) is provided with several rollers (311) for the raw material strips to be placed on and moved, or the raw material strips can be conveyed by a conveyor belt. The power unit (32) is the power source for driving the raw material strips to move. It can be composed of two upper and lower opposing rollers (321). The two rollers (321) are separated by a predetermined distance and can be driven to rotate by a power source (322). During transport, the extruded raw material strips are placed on the transport platform (31) and the outer ends of the raw material strips are clamped by the two rollers (321). As the raw material strips continue to be extruded, the power source (322) is also started at the same time, which drives the raw material strips to move on the transport platform (31). During the movement of the raw material strips, the fans (33) are used to blow air to cool them down.

Secondly, the cutting unit (40) is located on the outer side of the two rollers (321). It consists of a motor (42) mounted on a tool holder (41). The motor (42) drives a blade (43) to rotate. The radius of the blade (43) is greater than the width of the conveying platform (31). When the raw material strips pass through the two rollers (321), they will be cut into raw material particles by the rotating blade (43). Furthermore, a slide rail (44) is provided between the bottom of the motor (42) and the tool holder (41) to allow the motor (42) to be moved to adjust the cutting position of the blade (43).

After the raw material particles are cut, they are cooled while being transported using a second cooling system (50). The second cooling system (50) includes a collection bin (51), a first blower (52), a first cooling bin (53), a second cooling bin (54), a second blower (55), and a storage bin (56). A first pipeline (57) is provided between the collection bin (51) and the first cooling bin (53), a first and second pipeline (58) is provided between the first cooling bin (53) and the second cooling bin (54), and a third pipeline (59) is provided between the second cooling bin (54) and the storage bin (56). The first blower... The machine (52) is located at a suitable location on the first pipeline (57), and the second blower (55) is located at a suitable location on the third pipeline (59). After the raw material particles are cut and shaped, they fall into or are poured into the collection bucket (51). First, the first blower (52) is used to pump the raw material particles to the first cooling bucket (53), and then the second blower (55) is used to pump the raw material particles located in the first cooling bucket (53) to the storage bucket (56). The storage bucket (56) has a discharge port (561) at the bottom, and the packaging bag can be placed below the discharge port (561) for packaging operations to complete the production of raw material particles.

B. Drying raw material granules: When raw material granules are to be used to produce products using an injection molding machine (60), the raw material granules must first be placed in a hot dryer (not shown in the figure) for drying to reduce the moisture content of the raw material granules.

C. Heat the raw material granules. Place the dried raw material granules into the injection molding machine (60). The injection molding machine (60) has a barrel (61). The raw material granules can be placed into the feed tube (62) through the barrel (61). The feed tube (62) is equipped with a screw (63). The screw (63) rotates at high temperature to melt and mix the raw material granules into a molten state.

D. Injection molding: Molded fiber material is injected into a mold (64). The mold has several bottle cap cavities (641), and each bottle cap cavity (641) has a threaded module (642) for forming bottle cap threads. The fiber material is then injected into the bottle cap cavity (641).

E. Bottle cap thread shaping: After the molten fiber material is injected into the bottle cap mold cavity (641), the thread module (642) in the mold is removed to shape the thread in the bottle cap.

F. Demolding: After the fiber material of the bottle cap formed in the bottle cap mold cavity (641) cools and solidifies, the bottle cap (70) finished product can be demolded and taken out.

Therefore, by using pure natural plant materials to make raw material granules, and then using the raw material granules to produce bottle caps (70) that are biodegradable by ordinary soil and water through an injection molding machine, the bottle caps (70) have the effect of preventing bacterial adhesion. In summary, this invention has excellent progressive practicality among similar products. At the same time, a thorough search of domestic and foreign technical data and literature on this structure has not found any prior identical structure. Therefore, this invention has the requirements for a utility model patent, and an application is hereby filed in accordance with the law. The above embodiments are only used to illustrate this invention. Various modifications, alterations and applications made by those skilled in this technology without departing from the spirit of this invention should be included in the scope of this invention.

(11): First mixer (12): Second mixer (13): Third mixer (14): Fourth mixer (20): Forming device (21): Inlet (22): Outlet (23): Extrusion plate (231): Through hole (24): Conveying unit (25): Power screw (251): First Conveyor bar (252): Second conveyor bar (253): Third conveyor bar (254): Fourth conveyor bar (255): Blade (26): Exhaust pipe (27): Vacuum machine (30): First cooling system (31): Conveyor platform (311): Roller (32): Power unit (321): Roller (322) ): Power source (33): Fan (40): Cutting unit (41): Tool holder (42): Motor (43): Blade (44): Slide rail (50): Second cooling system (51): Collection bucket (52): First blower (53): First cooling tank (54): Second cooling tank (55): Second blower (56): Storage tank (561): Material outlet (57): First pipeline (58): Second pipeline (59): Third pipeline (60): Injection molding machine (61): Barrel (62): Material tube (63): Screw (64): Mold (641): Mold cavity (642): Threaded mold (70): Bottle cap

Figure 1: Schematic diagram of the raw material formula of this invention being mixed and processed into strips. Figure 2: Schematic diagram of the first cooling system and cutting unit of this invention. Figure 3: Schematic diagram of the composition and use of the second cooling system of this invention. Figure 4: Schematic diagram of the bottle cap application of this invention in injection molding production. Figure 5: Schematic diagram of the threaded die exiting the mold cavity of this invention. Figure 6: Side view of the finished bottle cap of this invention after demolding.

(11): First mixer

(12): Second mixer

(13): In the third mixer

(14): In the fourth mixer

(20): Molding device

(21): Feed inlet

(22): Discharge port

(23): Extrusion tray

(231): Through hole

(24): Conveyor Unit

(25): Power screw

(251): First conveyor bar

(252): Second conveyor bar

(253): Third conveyor bar

(254): Fourth conveyor bar

(255): Leaflets

(26): Exhaust pipe

(27): Vacuum machine

Claims (7)

An improved manufacturing process for biodegradable bottle caps includes the following steps: A. Obtaining raw material granules, the raw material granules comprising: 41.5–57.8% plant fiber powder, 22.3–28.5% starch, 9.5–26% natural binder (made from starch with added dicarboxylic acid and fermentation bacteria), 6–9.8% water-soluble polymer, 0.01–0.3% antibacterial agent, 3.2–5.8% coupling agent, 1–4% softener, and 0.02–0.18% lubricant; B. Drying the raw material granules by placing them in a hot dryer to reduce their moisture content. C. Raw material granule heating: The raw material granules are placed from the barrel of the injection molding machine into the feed tube and molten at high temperature using a screw. D. Injection molding: The molten fiber raw material is injected into the mold, which has several bottle cap cavities, into which the fiber raw material fills. E. Bottle cap thread setting: The thread block in the mold is removed to set the threads inside the bottle cap. F. Demolding: After the fiber raw material forming the bottle cap in the bottle cap cavity cools and sets, the bottle cap product can be demolded and removed. The biodegradable bottle cap manufacturing process improvement described in claim 1, wherein the water-soluble polymer can be a chemically modified natural polymer. The biodegradable bottle cap manufacturing process improvement described in claim 2, wherein the chemically modified natural polymer may be carboxymethyl starch or starch acetate. The biodegradable bottle cap manufacturing process improvement described in claim 1, wherein the lubricant may be a primary amide, a secondary amide, or ethylene distearate amide. The biodegradable bottle cap manufacturing process improvement described in claim 1, wherein the natural adhesive can be dried into powder, and the strain can be Aspergillus, yeast, lactic acid bacteria, or acetic acid bacteria. The biodegradable bottle cap manufacturing process improvement described in claim 1, wherein the antibacterial agent may be either nano silver or an antibacterial enzyme. The biodegradable bottle cap manufacturing process improvement described in claim 1, wherein the softener may be an ester-based quaternary ammonium salt.