Medicinal plastic bottle optimization design essentials
With the rapid development of China's pharmaceutical industry, the pharmaceutical packaging industry has begun to move forward and become an important part of the development of China's pharmaceutical industry. At present, the overall technical level of China's pharmaceutical packaging industry is not high, lagging far behind the developed countries. In the developed countries, pharmaceutical packaging accounts for 30% of the drug value, but China is still less than 10%. In the next five years, it will still be a critical period for the rapid development of China's pharmaceutical industry, and it is tempting for huge business opportunities. Among the many factors of commodity competition in the international market, product quality, price and packaging design are the three main factors. As a foreign marketing expert said: “In the path to the market, packaging design is the most important one, packaging plays a role in the overall image of the product as much as advertising.†So we must seize this opportunity for development. , brave to innovate, unconventional, make the product novel, bizarre, full of modern consciousness
The ability to develop and manufacture competitive products is the key to business survival and development. The birth of competitive products starts with the optimal design of the product.
The first point of optimization design: It must be understood that plastic bottles should have the following functions.
1) The plastic bottle must have the function of protecting the contents. The plastic bottle can be protected against moisture, water, dust and corrosion. Blocking of dust, water, and other liquid substances from outside; Preventing contamination and corrosion of packaging materials; Preventing penetration of UV rays, adapting to changes in ambient temperature, and protecting packages from sunlight and UV rays.
2) The plastic bottle must have the function to withstand the external force, it can adapt to a variety of transport modes and storage methods, protect the contents will not be damaged.
3) The plastic bottle makes the product display function. The plastic bottle can display the display function of the product through beautiful appearance, vivid colors, smooth surface and transparency. Attract customers and stimulate customers' desire to buy.
For example, bottles of different colors can clearly indicate the series, type, or model of the product. The transparent plastic bottle can show the color and quality of the contents. The translucent plastic bottle can partially display or conceal the contents. The opaque plastic bottle cans. Load items with various colors. Printed on the surface of plastic bottles, the printed information can be passed directly to consumers.
Plastic bottles should have easy-to-use features. The opening of plastic bottles should be designed to be easy to open, open and closed multiple times, and easy to dump the contents. Can not cause spatter injury. When designing a product, additional functions can be added to the sealer: eg, anti-counterfeit, anti-theft, anti-blocking, spray, etc.
The second point of optimization design is that at the beginning of product design, designers must conduct market research, specify customer requirements, learn the longevity of similar products in the same industry, be familiar with the company's molding equipment and production technology, and establish the design products. Preliminary concept.
The third point of optimization design is based on various technical materials, my own design experience and imagination, material formula, and molding process. The courage to innovate and design a product map, a product rendering or a model to form a preliminary design. Design considerations include: product stiffness and shape design, printed surface design, edge and wipe design, bottle finish design, bottom design, and more.
Plastic bottles should have sufficient rigidity and aesthetic appearance. The most common shapes of plastic bottles are round, square, oval and so on. From the use point of view, they have their own advantages and disadvantages. The round plastic bottle has a high stiffness, but its appearance is not beautiful. The shape of the square plastic bottle is beautiful, but it is not easy to control the wall thickness of the plastic bottle when molding. Oval-shaped plastic bottles are also high in rigidity, but the manufacturing cost of the molds is high. Therefore, in order to ensure the rigidity of the plastic bottle, besides selecting a material with high rigidity, the shape of the plastic bottle must be designed to enhance the rigidity and load bearing strength of the plastic bottle.
1) Change the surface shape of plastic bottles. For example, if the middle of a plastic bottle is relatively small, increasing the circumferential grooves or ribs on the surface of plastic bottles can increase the rigidity and bending resistance of plastic bottles. Longitudinal grooves or ribs eliminate plastic bottle deflection, sagging or deformation under long-term loading.
2) In the design of extruded plastic bottles, if the material is high-density polyethylene or polypropylene, the cross-section of the plastic bottle should be rectangular or oval, for the material of low density polyethylene or other flexible plastic bottle, its cross-section Take a round shape as well. This facilitates the extrusion of the contents from the plastic bottle.
3) In order to make the plastic bottle wall thickness uniform, it should be noted that the shape of the plastic bottle should have symmetry. Minimize extreme stretch points and locations. All transitions use circular transitions.
4) The printing surface of plastic bottles is the most concentrated part of consumers' attention. The printing surface should be flat and continuous; if the plastic bottle contains handles, grooves, ribs, etc., the design should be careful not to cause inconvenience to the printing operation.
5) When the surface of the plastic bottle is labelled, the label surface should be flat. A "sash" can be designed on the surface of the plastic bottle so that the tag can be accurately positioned without movement.
6) At the time of blow molding, the part where the parison inflates first contacts always tends to harden in advance. Therefore, the wall thickness of this part is also larger. The edge and the corner are the parts where the parison is inflated last, and the wall thickness is smaller. Therefore, the edge of the plastic bottle and the corner should be rounded.
7) Since most plastics have notch sensitivity, plastic bottles are susceptible to cracking and cracking at sharp corners, at the root of the mouth thread, and at the neck, so these parts should be rounded. For the transfer of rectangular plastic bottles, it is necessary to support most of the load on the plastic bottles. Therefore, increasing the wall thickness locally will help improve the rigidity and load-bearing strength of the plastic bottles. The plastic parts used with the plastic bottle mouth are mainly caps and sealers. The design of plastic bottle mouth should focus on examination; how to make the plastic bottle mouth fit with the lid and sealer better with the bottom of the plastic bottle is a weak part of the mechanical properties of the plastic bottle. Therefore, the bottom of the plastic bottle is generally designed to be concave; the corners of the plastic bottle, as well as the inner cavity, are all subject to large arc oversizing. In order to facilitate the stacking of plastic bottles and increase the stacking stability of plastic bottles, the bottom of plastic bottles should be designed with inner grooves.
The fourth point of optimizing the design is to extensively listen to everyone's comments on the preliminary design, and make repeated modifications after repeated modifications. Including the product after the trial change, the customer's final modification, until the final confirmation of the type. Plastics have a variety of molding methods and they can all be used to make plastic bottles of different shapes and purposes. Among them, blow molding is one of the most widely used and one of the largest production methods. Extrusion blow molding is the earliest and most used process for producing plastic blow-molded plastic bottles. Its processes include the extrusion of plastics, the preparation of parisons, the inflation and cooling of parisons, the opening of molds and the removal of products. Products that have been demolded, according to design requirements, also need processing and testing. Stretch blow molding, also known as biaxial orientation blow molding. It is to make thermoplastics by extrusion or injection process into parisons, the tempering process, so that the parison is in a high-elastic state of polymer, the first axial mechanical stretching, and then pulled axially with compressed air Stretch, a method of forming a biaxial plastic bottle. Stretch-orientated plastic bottles have better physical and mechanical properties and economy than non-stretched oriented plastic bottles. Stretch-blow plastic bottles have a growing trend. Among the various biaxial stretch blow-molded plastic bottles, PET bottles are the most used; PP stretch blow-molded bottles are the fastest growing in the United States; hot-fillable, reusable PET bottles are being The rapid rise of the market. Guangzhou Tech-Long Packaging Machinery Co., Ltd. recently developed the first fully-automatic rotary high-speed PET bottle blowing machine in China with a production speed of 8600 per hour. This new type of blowing machine is fully automatic during the entire operation process from the top billet to the bottle, unqualified product inspection and troubleshooting. The technical level is leading domestically and fills domestic blank injection blow molding. It is composed of injection and blow molding. A blow molding method. The injection molding process was used to make parisons that were used in the 1950s. It was used as an accessory process for injection molding. However, due to lack of plastic varieties, mold manufacturing technology, market, and other reasons, it failed to promote the application. Until the 1980s, the development of modern plastic molding technology only expanded in the field of plastic bottle manufacturing. In the future, with the miniaturization of households, the safety of packaging materials and the growth of supermarkets, the demand for small bottles of plastic bottles will continue to grow. At the same time, the plastic products industry will further reduce the cost of molds, adopt long blow molding, use new plastic products and models, and the emergence of a new generation of blow molding machines will bring greater development to injection blow molded plastic bottles. The rapid development of China's pharmaceutical packaging industry, the growing demand for plastic packaging plastic bottles, blow molding equipment is also growing. As the injection blow molding equipment is in operation, the bottle mouth is first injected, the precision of the bottle mouth is maintained, and then the bottle body is blown. Therefore, the gas in the plastic bottle can be prevented from evaporating and the outside air can penetrate into the bottle. This ensures a very close performance between the bottle mouth and the bottle cap. China's plastic injection molding hollow plastic bottle equipment can now be produced in small quantities, but the precision and performance of the equipment itself are not as good as foreign equipment.
At present, the production of this kind of equipment needs to increase the level of precision. The development direction of injection blowers in China in the coming period will be: 1) Hydraulic control systems with high sensitivity, high reproducibility and stability.
2) It has fine-tuned control performance, excellent and reliable operation, and easy-to-use electronic control system.
3) It has an excellent plasticizing device that can fully plasticize the plastic under uniform temperature and can measure correctly.
4) High-speed high-pressure injection of parisons can be used to minimize shrinkage of plastic bottles during blow molding.
5) Precision injection molds. Development of blow mold design and manufacturing technology.