I. Status of color printing plastic flexible packaging
According to statistics, from 1993 to 1998, the output value of the food industry increased from RMB 342.8 billion to RMB 590 billion (calculated at constant prices in 1990), with an average annual increase of 11.6%. It is estimated that by 2000, the output value of the food industry in China could exceed 3%. Trillion, will become China's largest industry. It is the color printing plastic flexible packaging industry that provides packaging for the food industry.
One of the contributions of the plastic flexible packaging industry to the market economy is to promote the sale of goods through the design and production of product packaging. Experts argued that 53% of the external intelligence received by human senses came from visual sensing, 11% from auditory reception, 35% from olfactory perception, and 1% sense of taste. It can be seen that the visual system receives the external information is the most commonly used and the highest frequency of a sense, color printing plastic flexible packaging design and production, just completely able to approach people's visual field completely. What is the value of our plastic flexible packaging industry, especially the packaging produced by various companies in product promotion? It can be calculated using the formula provided by the International Statistical Association. A good package can increase sales by 15 to 18%, that is:
15% (18%) × current year sales × sales profit × sales extended for three years
This is the value of the packaging.
According to the data provided by the American Design Association, good image design and advertising in social business functions have a ratio of input to output of $1:227.
Another important contribution of the plastic flexible packaging industry to the market economy lies in the formation of an industry based on color-printed plastic flexible packaging and related industries supporting services through the creation of a large number of jobs, economic development, and a new economy. growth point.
Color printing plastic flexible packaging was developed rapidly in China in the 1990s. This is due to the policy of reform and opening up in China and benefits from the development of science and technology and the development of polymer chemistry industry. Color printing plastic flexible packaging introduction of technology, equipment, materials, and gradually achieve domestic self-supply. The output of plastic packaging materials grew from 380,000 tons in 1982 to 2.43 million tons in 1996, with an average annual growth rate of 14.17%. The proportion of the total industrial output value of the plastic packaging industry in the packaging industry has reached 26.49%, 2.5 times that of the metal packaging industry and 4.16 times that of the glass packaging industry. The proportion of total assets is 24.4% of the packaging industry, 2.2 times of the metal packaging industry and 3.74 times of the glass packaging industry. In 1999, plastic packaging products reached 3.35 million tons, which was 1.38 times that of 1996. Since 1996, the average annual growth rate is 34.47%.
The development of color printing plastic flexible packaging industry has driven the development of BOPP, PE, PET, CPP, vacuum aluminum plating, pearl film and other plastic film production enterprises. In 1998, China had more than 70 film production lines, together with the development of China's petrochemical industry and product innovation.
The development of color printing plastic flexible packaging industry has also led to the development of gravure printing technology and flexo printing technology. In 1996, in the packaging printing in the United States, flexographic printing accounted for more than 70%. And at a rate of 15% each year, 60% of Italy's packaging printing is using flexible printing. The current ratio of flexo printing to gravure printing in packaging printing is:
Region Americas Europe Asia
Flexible printing 50% 40% 8%
Gravure printing 50% 60% 92%
This provides a great space for the application of flexible printing technology. The development of color printing plastic flexible packaging industry has led to multi-color gravure printing machine and computer automatic registration technology, dry laminating machine, slitting machine and photoelectric correction technology, various forms of bag making machines, printing and packaging machinery and auxiliary materials, flexible printing Machine and auxiliary material development. Dalian, Tangshan, Tianjin, Shanghai, Wuxi, Shantou, Wenzhou, Ruian, Guangzhou, and other full-scale plastic flexible packaging machinery production bases have been formed. At the same time, ink production has also been promoted, forming Tianjin Dongyang, Shanghai Keleikakbai, and Kangzhou-Hangzhou. China, Taiyuan Gao's Laurel, Guangdong Shunde Jinlong, Shenzhen Shenzhen, Japan's New Oriental, Shanghai DIC, Fujian Fuzhou, Shanghai Hanlian, Zhejiang Yong in, Guangdong Jiangmen Dongyang, Gansu Gansu, Guangdong Meining, and other annual output of 200011003t ink Manufacturer. This has led to the development of the laser engraving and platemaking industry represented by the engraved plate engraving industry in Liancheng, Shanxi, and the ceramic roller, represented by Shanghai in recent years.
The development of color printing plastic flexible packaging industry has not only created many job opportunities for itself, but also provided new business opportunities for packaging design, material supply, raw material product transportation and other industries. Has begun to form a new industry based on color printing plastic flexible packaging processing. Only Jingtou Village, Jingtou Township, Suzhou City, Jiangsu Province, was a small village with only 3 points of poor land, and it used to think that “this is a kind of golden beans that cannot make people richâ€. In 1998, it achieved the development of colorful plastic packaging for batteries. The output value of 59 million yuan, the per capita net income of farmers 3995 yuan, the product accounted for 80% of the domestic market share, tentacles distribution north and south, inside and outside the Great Wall, and even China-Burma border, the product supply more than 20 provinces, municipalities and autonomous regions of the 130 large and medium-sized batteries The factory recently signed an agreement with Changhong Group, the largest color TV manufacturer in the country, for the Changhong Alkaline Battery Color Plastic packaging fixed-point production base. The village has more than 250 peasant households engaged in the processing industry. Several private enterprises have fixed assets of more than one million yuan and employ more than 100 people. The village has more than 150 vehicles and vessels for product transportation. The rise and development of color printing plastic flexible packaging industry has injected new vitality into old enterprises, increased the original science and technology content of township enterprises, and at the same time opened up new avenues for the development of individual proprietorship enterprises, and made a social stability and economic prosperity for China. Historical contribution.
Although China's color printing plastic flexible packaging industry started late, it has a relatively high starting point. Polymer materials engineering closely follows the development of world science and technology. Large-scale film production lines of various materials are the most advanced equipments of the 20th century. Computer technology has been applied to the entire process of raw material production, product design, and packaging processing. ISO9000 quality certification The system has been established in many factories. The ISO14000 environmental management international standard has already begun to be accepted domestically. Products that use color printing plastic flexible packaging as the main body have already been traded abroad. The signing of the WTO agreement has provided China with more convenient conditions for opening up to the outside world, and at the same time opened a new channel for the technical exchange of plastic flexible packaging and export of products, and opened up a broader market.
Second, color printing plastic flexible packaging process
Color printing plastic flexible packaging technology is a combination of plastic film color printing technology, plastic film composite technology, plastic composite material bag making technology. First of all, in the plastic film inside the printing of color Yang Wen, and other materials of different materials (such as PE, CPP, PET, transparent, vacuum aluminum, pearlescent) compound, and then make a variety of seals according to design requirements Style, different specifications of plastic composite bags. The process flow is as follows:
Plastic film color printing process → Plastic film composite process → Plastic composite material bag making process
The color printing inside the plastic film is to attract the attention of consumers through the brilliant colors of the packaging graphic design, and then to have a deep understanding of the product, generate interest and possessive desire, achieve the best purpose of the first impression. Therefore, in the plastic color printing process, design is the most critical task.
Plastic film color printing process
Concept Design→Electro-engraving→Prepression→Tint Match→Print Sample→Color Gravure
Plastic film composite process
Base film preparation → glue liquid adjustment → glue drying → pressurization compounding → correction rewinding
Plastic composite bag making process
Substrate Preparation → Specification → Temperature Setting → Pressure Setting → Speed ​​Adjustment → Finished Product Inspection
The composite material in the plastic flexible packaging is a material that has a special function of heating and self-adhesion and is composed of a BOPP printing film and an inner liner film having heat sealing properties such as PE, PET, CPP. The plastic composite material bag making process is to explore the characteristics of the use of PE, PET, CPP and other substrates, and use the electric heating device of the bag making machine to generate the phase change from the solid state to the viscous flow state of the heated parts, with the help of the power of the cutter. The upper and lower two layers of film are integrated with each other and can maintain a certain strength after cooling.
Different kinds of plastic films have different heat sealing temperatures. (See the table below).
Plastic film heat sealing temperature meter
Film material Heat sealing temperature (°C)
LDPE low density polyethylene 20~175
HDPE high density polyethylene 135~155
Linear Low Density Polyethylene 175～180
PP polypropylene (unstretched) 165-205
OPP polypropylene (stretched) 100～130
PVC polyvinyl chloride 95~175
PVDC polyvinylidene chloride 90～200
PET polyester 150～190
PC polycarbonate 205~430
PA polyamide 175～260
PS polystyrene 120~165
PT cellophane 205～260
PT cellophane (with paint) 95～260
According to the above parameters, grasping the heat sealing temperature and selecting the best viscous flow state of the lining material are the core technologies of the bag making process.
Increasing the temperature reduces the viscosity or apparent viscosity of the polymer melt. PE and PP are non-polar polymers with minimal activation energy and minimal curve. The increase in temperature is large, but the apparent viscosity is reduced minimally. Heat sealing must be carried out at a viscous flow temperature above Tt (or Tm above melting point). However, the decomposition temperature Ta cannot be exceeded. In order to avoid thermal degradation.
Plastic composite bag making process, namely heat sealing process. The heat sealing process has three major factors: heat sealing temperature (T), heat sealing pressure (P), and heat sealing time (t). When the optimal value of heat seal temperature (T) is selected, the heat seal pressure (P) should not be too large, and the heat seal time (t) should not be too long. The best heat sealing temperature has transformed the plastic film from a solid state to a viscous flow state. The best heat sealing pressure (P) and action time (t) can ensure the fusion of the upper and lower films. Excessive pressure (P) or excessively long time (t) results in degradation of macromolecules, lowering the seal strength, and degrading the interface sealability.
Third, the plastic color printing trademark bending reasons
The printing industry in the modern printing industry develops from monochrome to six-color and eight-color. The efficiency has evolved from multi-process to one-step molding, integrating printing, cutting, embossing, bronzing, and laser. In the process of mechatronics, a series of new problems will inevitably arise in production. Trademark bending is a quality problem often encountered in the production of one-shot molding. Trademark bending not only affects the appearance of the trademark, but also directly impairs the user's applicability to the computer, causing users to discontinue their use of the trademark. How to effectively solve and control the occurrence of trademark bending in production is of great significance to improving product quality and satisfying users' needs.
Why does the film bend in the printing process?
From the test, it is known that under a certain pressure and temperature conditions, the greater the tensile force, the higher the temperature, the greater the deformation of the film.
In the process of one-step forming of gravure multi-color machine, the film is subjected to 20 to 35 daN tension, 25 to 40 daN pressure, and drying temperature of 60 to 100°C. After many times of printing, drying, stretching, and recovery, deformation occurs to varying degrees. Moreover, in printing, due to the application of ink, it will cause local and lateral double-sided stretching, deformation, and recovery of the film on the lateral width of the film, resulting in trademark bending phenomenon in the finished product, especially poor quality of the tension. The film will be severely bent.
For the bending phenomenon in the production of trademarks, the following measures can be taken:
(a) film control
In order to reduce the bending of the trademark, in the selection of printed film brands,
According to statistics, from 1993 to 1998, the output value of the food industry increased from RMB 342.8 billion to RMB 590 billion (calculated at constant prices in 1990), with an average annual increase of 11.6%. It is estimated that by 2000, the output value of the food industry in China could exceed 3%. Trillion, will become China's largest industry. It is the color printing plastic flexible packaging industry that provides packaging for the food industry.
One of the contributions of the plastic flexible packaging industry to the market economy is to promote the sale of goods through the design and production of product packaging. Experts argued that 53% of the external intelligence received by human senses came from visual sensing, 11% from auditory reception, 35% from olfactory perception, and 1% sense of taste. It can be seen that the visual system receives the external information is the most commonly used and the highest frequency of a sense, color printing plastic flexible packaging design and production, just completely able to approach people's visual field completely. What is the value of our plastic flexible packaging industry, especially the packaging produced by various companies in product promotion? It can be calculated using the formula provided by the International Statistical Association. A good package can increase sales by 15 to 18%, that is:
15% (18%) × current year sales × sales profit × sales extended for three years
This is the value of the packaging.
According to the data provided by the American Design Association, good image design and advertising in social business functions have a ratio of input to output of $1:227.
Another important contribution of the plastic flexible packaging industry to the market economy lies in the formation of an industry based on color-printed plastic flexible packaging and related industries supporting services through the creation of a large number of jobs, economic development, and a new economy. growth point.
Color printing plastic flexible packaging was developed rapidly in China in the 1990s. This is due to the policy of reform and opening up in China and benefits from the development of science and technology and the development of polymer chemistry industry. Color printing plastic flexible packaging introduction of technology, equipment, materials, and gradually achieve domestic self-supply. The output of plastic packaging materials grew from 380,000 tons in 1982 to 2.43 million tons in 1996, with an average annual growth rate of 14.17%. The proportion of the total industrial output value of the plastic packaging industry in the packaging industry has reached 26.49%, 2.5 times that of the metal packaging industry and 4.16 times that of the glass packaging industry. The proportion of total assets is 24.4% of the packaging industry, 2.2 times of the metal packaging industry and 3.74 times of the glass packaging industry. In 1999, plastic packaging products reached 3.35 million tons, which was 1.38 times that of 1996. Since 1996, the average annual growth rate is 34.47%.
The development of color printing plastic flexible packaging industry has driven the development of BOPP, PE, PET, CPP, vacuum aluminum plating, pearl film and other plastic film production enterprises. In 1998, China had more than 70 film production lines, together with the development of China's petrochemical industry and product innovation.
The development of color printing plastic flexible packaging industry has also led to the development of gravure printing technology and flexo printing technology. In 1996, in the packaging printing in the United States, flexographic printing accounted for more than 70%. And at a rate of 15% each year, 60% of Italy's packaging printing is using flexible printing. The current ratio of flexo printing to gravure printing in packaging printing is:
Region Americas Europe Asia
Flexible printing 50% 40% 8%
Gravure printing 50% 60% 92%
This provides a great space for the application of flexible printing technology. The development of color printing plastic flexible packaging industry has led to multi-color gravure printing machine and computer automatic registration technology, dry laminating machine, slitting machine and photoelectric correction technology, various forms of bag making machines, printing and packaging machinery and auxiliary materials, flexible printing Machine and auxiliary material development. Dalian, Tangshan, Tianjin, Shanghai, Wuxi, Shantou, Wenzhou, Ruian, Guangzhou, and other full-scale plastic flexible packaging machinery production bases have been formed. At the same time, ink production has also been promoted, forming Tianjin Dongyang, Shanghai Keleikakbai, and Kangzhou-Hangzhou. China, Taiyuan Gao's Laurel, Guangdong Shunde Jinlong, Shenzhen Shenzhen, Japan's New Oriental, Shanghai DIC, Fujian Fuzhou, Shanghai Hanlian, Zhejiang Yong in, Guangdong Jiangmen Dongyang, Gansu Gansu, Guangdong Meining, and other annual output of 200011003t ink Manufacturer. This has led to the development of the laser engraving and platemaking industry represented by the engraved plate engraving industry in Liancheng, Shanxi, and the ceramic roller, represented by Shanghai in recent years.
The development of color printing plastic flexible packaging industry has not only created many job opportunities for itself, but also provided new business opportunities for packaging design, material supply, raw material product transportation and other industries. Has begun to form a new industry based on color printing plastic flexible packaging processing. Only Jingtou Village, Jingtou Township, Suzhou City, Jiangsu Province, was a small village with only 3 points of poor land, and it used to think that “this is a kind of golden beans that cannot make people richâ€. In 1998, it achieved the development of colorful plastic packaging for batteries. The output value of 59 million yuan, the per capita net income of farmers 3995 yuan, the product accounted for 80% of the domestic market share, tentacles distribution north and south, inside and outside the Great Wall, and even China-Burma border, the product supply more than 20 provinces, municipalities and autonomous regions of the 130 large and medium-sized batteries The factory recently signed an agreement with Changhong Group, the largest color TV manufacturer in the country, for the Changhong Alkaline Battery Color Plastic packaging fixed-point production base. The village has more than 250 peasant households engaged in the processing industry. Several private enterprises have fixed assets of more than one million yuan and employ more than 100 people. The village has more than 150 vehicles and vessels for product transportation. The rise and development of color printing plastic flexible packaging industry has injected new vitality into old enterprises, increased the original science and technology content of township enterprises, and at the same time opened up new avenues for the development of individual proprietorship enterprises, and made a social stability and economic prosperity for China. Historical contribution.
Although China's color printing plastic flexible packaging industry started late, it has a relatively high starting point. Polymer materials engineering closely follows the development of world science and technology. Large-scale film production lines of various materials are the most advanced equipments of the 20th century. Computer technology has been applied to the entire process of raw material production, product design, and packaging processing. ISO9000 quality certification The system has been established in many factories. The ISO14000 environmental management international standard has already begun to be accepted domestically. Products that use color printing plastic flexible packaging as the main body have already been traded abroad. The signing of the WTO agreement has provided China with more convenient conditions for opening up to the outside world, and at the same time opened a new channel for the technical exchange of plastic flexible packaging and export of products, and opened up a broader market.
Second, color printing plastic flexible packaging process
Color printing plastic flexible packaging technology is a combination of plastic film color printing technology, plastic film composite technology, plastic composite material bag making technology. First of all, in the plastic film inside the printing of color Yang Wen, and other materials of different materials (such as PE, CPP, PET, transparent, vacuum aluminum, pearlescent) compound, and then make a variety of seals according to design requirements Style, different specifications of plastic composite bags. The process flow is as follows:
Plastic film color printing process → Plastic film composite process → Plastic composite material bag making process
The color printing inside the plastic film is to attract the attention of consumers through the brilliant colors of the packaging graphic design, and then to have a deep understanding of the product, generate interest and possessive desire, achieve the best purpose of the first impression. Therefore, in the plastic color printing process, design is the most critical task.
Plastic film color printing process
Concept Design→Electro-engraving→Prepression→Tint Match→Print Sample→Color Gravure
Plastic film composite process
Base film preparation → glue liquid adjustment → glue drying → pressurization compounding → correction rewinding
Plastic composite bag making process
Substrate Preparation → Specification → Temperature Setting → Pressure Setting → Speed ​​Adjustment → Finished Product Inspection
The composite material in the plastic flexible packaging is a material that has a special function of heating and self-adhesion and is composed of a BOPP printing film and an inner liner film having heat sealing properties such as PE, PET, CPP. The plastic composite material bag making process is to explore the characteristics of the use of PE, PET, CPP and other substrates, and use the electric heating device of the bag making machine to generate the phase change from the solid state to the viscous flow state of the heated parts, with the help of the power of the cutter. The upper and lower two layers of film are integrated with each other and can maintain a certain strength after cooling.
Different kinds of plastic films have different heat sealing temperatures. (See the table below).
Plastic film heat sealing temperature meter
Film material Heat sealing temperature (°C)
LDPE low density polyethylene 20~175
HDPE high density polyethylene 135~155
Linear Low Density Polyethylene 175～180
PP polypropylene (unstretched) 165-205
OPP polypropylene (stretched) 100～130
PVC polyvinyl chloride 95~175
PVDC polyvinylidene chloride 90～200
PET polyester 150～190
PC polycarbonate 205~430
PA polyamide 175～260
PS polystyrene 120~165
PT cellophane 205～260
PT cellophane (with paint) 95～260
According to the above parameters, grasping the heat sealing temperature and selecting the best viscous flow state of the lining material are the core technologies of the bag making process.
Increasing the temperature reduces the viscosity or apparent viscosity of the polymer melt. PE and PP are non-polar polymers with minimal activation energy and minimal curve. The increase in temperature is large, but the apparent viscosity is reduced minimally. Heat sealing must be carried out at a viscous flow temperature above Tt (or Tm above melting point). However, the decomposition temperature Ta cannot be exceeded. In order to avoid thermal degradation.
Plastic composite bag making process, namely heat sealing process. The heat sealing process has three major factors: heat sealing temperature (T), heat sealing pressure (P), and heat sealing time (t). When the optimal value of heat seal temperature (T) is selected, the heat seal pressure (P) should not be too large, and the heat seal time (t) should not be too long. The best heat sealing temperature has transformed the plastic film from a solid state to a viscous flow state. The best heat sealing pressure (P) and action time (t) can ensure the fusion of the upper and lower films. Excessive pressure (P) or excessively long time (t) results in degradation of macromolecules, lowering the seal strength, and degrading the interface sealability.
Third, the plastic color printing trademark bending reasons
The printing industry in the modern printing industry develops from monochrome to six-color and eight-color. The efficiency has evolved from multi-process to one-step molding, integrating printing, cutting, embossing, bronzing, and laser. In the process of mechatronics, a series of new problems will inevitably arise in production. Trademark bending is a quality problem often encountered in the production of one-shot molding. Trademark bending not only affects the appearance of the trademark, but also directly impairs the user's applicability to the computer, causing users to discontinue their use of the trademark. How to effectively solve and control the occurrence of trademark bending in production is of great significance to improving product quality and satisfying users' needs.
Why does the film bend in the printing process?
From the test, it is known that under a certain pressure and temperature conditions, the greater the tensile force, the higher the temperature, the greater the deformation of the film.
In the process of one-step forming of gravure multi-color machine, the film is subjected to 20 to 35 daN tension, 25 to 40 daN pressure, and drying temperature of 60 to 100°C. After many times of printing, drying, stretching, and recovery, deformation occurs to varying degrees. Moreover, in printing, due to the application of ink, it will cause local and lateral double-sided stretching, deformation, and recovery of the film on the lateral width of the film, resulting in trademark bending phenomenon in the finished product, especially poor quality of the tension. The film will be severely bent.
For the bending phenomenon in the production of trademarks, the following measures can be taken:
(a) film control
In order to reduce the bending of the trademark, in the selection of printed film brands,
We provide hanging Display Stand the lovely small items in life, people's interests and hobbies, can be hung here, to show its wonderful and practical.
The advantage of hanging display stand
Easy to assemble
Durable, portable
Original design, color printing
100% quality ensured
Hanging Display Stand
Hanging Display Stand,Supermarket Display Stand,Retail Display Stands,Small Display Stands
JiaDi Environmental Packaging Technology Co., Ltd , http://www.jiadipaper.com