Dongguan C&S Plastic Produce Factory|
Dongguan Wede Packaging Materials Co.,Ltd.
Address:128 Industrial Park,Tangxia Town,Dongguan City
Introduction of plastic packaging materials|
2010-5-14 17:51:11 http://www.packinghx.com hots:6710
PE (polyethylene) film |
Maximum use of plastic packaging films, about 40% of the total amount. PE film though not very satisfactory in appearance, but it has good toughness, moisture resistance and sealing properties, and processing of shape convenient, cheap, used very widely.
LDPE is a flexible and transparent non-toxic odorless, 20-100 microns in thickness, with good water resistance, moisture resistance, drought resistance and chemical stability. Used extensively for food, medicines, daily necessities, and metal products, general proof packaging and frozen food packaging. But for a large moisture absorption, moisture demanding items, you need proof of a better film and composite film packaging. LDPE film permeability rate is high, no fragrance and oil security is poor and can not easily oxidized food and oil for food packaging. However, permeability so that it can used for fruit, fresh vegetables such as packaging. LDPE film adhesion and low temperature heat seal is good, it is often used as adhesive layer and composite film sealing layer. However, because of its poor heat resistance, it can not be used as a cooking bag sealing layer.
LDPE (low density polyethylene), in the ultra-100 ~ 200Mpa polymerization under high pressure, density of 0.92 grams / cubic centimeter, in high, medium and low in polyethylene, LDPE opacity.
MDPE (medium density polyethylene), in 10Mpa the polymerization under pressure, density of 0.93 to 0.94 grams / cubic centimeter,
HDPE is a tough, translucent film, its appearance is white, poor surface gloss. HDPE tensile strength, moisture resistance, heat resistance, oil resistance and chemical stability are better than LDPE, can also seal together, but transparent as LDPE. HDPE can be made of thin film thickness of 0.01mm, its appearance and thin like silk, feel comfortable, also known to be paper membrane. It has good toughness and the opening of strength. HDPE to be the main language paper membrane to produce all kinds of shopping bags, garbage bags, fruit bags and various food packaging bags. Because of its poor air tightness fragrance does not have insurance, so the storage of packaged food is not long. In addition, HDPE due to heat stroke feel good, be used as a cooking bag sealing layer.
HDPE (high density polyethylene), polymerization under normal pressure, density of 0.94 ~ 0.985 g / cc, HDPE poor transparency.
LLDPE has higher tensile strength than LDPE, impact strength, tear strength and puncture resistance for daily packaging, frozen food packaging, is also used extensively for heavy bags and garbage bags. (Materials less cost)
LLDPE (linear low density polyethylene), processing more difficult, high cost, it is generally used with LDPE film with the system in general as the inner bag seal material
M-PE (metallocene polyethylene) to the synthesis of metallocene-based polyethylene catalysts, including Take M-LLDPE material used for the market, M-LLDPE and LLDPE compared to tensile strength, toughness, puncture resistance, transparency , sealing performance are better than, well, and the low temperature heat sealing, heat sealing temperature range, and strong anti-pollution sealing.
PP (polypropylene) film
Divided into non stretch film and biaxially oriented film. Difference in the performance of two films too, should be considered in two different films.
1. Not oriented polypropylene film, divided into the production of extrusion blow molding blow-molded polypropylene film (IPP) and T membrane production of extrusion cast polypropylene film (CPP). PP film transparency and toughness, and transparency. CPP has better transparency and gloss, it looks close to the cellophane. Compared with PE, PP does not stretch better transparency, gloss, moisture resistance, heat resistance and oil resistance, mechanical strength, tear resistance, puncture resistance and good wear resistance and Wudu odorless. It is widely used in food, pharmaceuticals, textiles and other items of packaging. PP film is not stretched high heat resistance and good sealing performance, so often used as cooking bag sealing layer, especially for high temperature (121 degrees) of the retort pouch. But poor drought tolerance, when brittle at 0-10 degrees Celsius, it is not used for frozen food packaging. In addition, after the aluminum CPP BOPP, PET, PA and so complex, as the inner sealing material used.
2. Biaxially oriented polypropylene film (BOPP), compared with not stretching PP film, BOPP has the following main characteristics:
① transparency, gloss improvement comparable with cellophane
② mechanical strength increased, but elongation decreased
③ increase drought tolerance, -30 ~ -50 degrees Celsius in the use of non-brittle
④ permeability rate, ventilation rate was reduced by approximately half of the organic vapor transmission rate is also significantly lower
⑤ single heat sealing film can not be directly combined, but the adhesive coating can be combined with other plastic films to improve the sealing of
BOPP film is developed for the purpose of cellophane instead of a new type of packaging film. It has high mechanical strength, good toughness, good transparency and gloss and so on. The price is about 20% lower than the cellophane, so in food, drugs, cigarettes, textiles, packaging has been replaced or partially replaced the cellophane, but its back elastic, kink can not be used for candy packaging. BOPP films are widely used in composite film substrate, with aluminum foil and other plastic film made of composite film to meet packaging requirements for various items.
Very good transparency, heat resistance, better than CPP, but also a good barrier, as a package bag's outer layer is basically printing materials. There is also can be heat sealed BOPP, can be made into separate bags.
PA (polyamide) film, commonly known as NY (NYLON Nylon)
There are two kinds of two-way stretch and non stretch, including two-way stretch nylon (BONY) to use more, not stretch nylon film has outstanding elongation, mainly for deep drawing vacuum packaging.
Nylon film is a very tough film, non-toxic tasteless, transparent and good, glossy, easy accumulation of static electricity, the printing is good, its high mechanical strength, tensile strength is three times the PE film, wear resistance, resistance to expose excellent. Nylon film heat resistance, oil resistance, sweat resistance, and good, but more difficult to seal, nylon film in dry conditions with good air tightness. But it's breathable rate and large, absorbent, high humidity environment, poor dimensional stability, air tightness sharply. So common PVDC coating (called KNY), or combined with PE film to improve its water resistance, wet resistance and sealing properties, etc., this NY / PE composite film is widely used in food packaging. Nylon packing a lot for the production of composite films, but also for aluminum thin film substrate.
Nylon film and the composite film is mainly used for greasy food, general food, frozen food and cooking food products. Not stretch nylon membrane expression for elongation could taste beef, more than flesh and blood and other food vacuum packaging.
Also because of its flexibility, in the re-packaging bags are also commonly used as a reinforcing material.
PET (polyester) film
Two-way stretch (BOPET) most widely used. PET is a more comprehensive performance packaging film, the transparency is good, shiny, good air tightness and Paul Hong, moisture, moderate rate of decline in moisture permeability at low temperatures, PET's excellent mechanical properties, its intensity Toughness is the best of all thermoplastic, tensile strength and impact strength much higher than the average film, and pretty good strength, dimensional stability, suitable for printing, bag making and other secondary processing. PET film also has excellent heat resistance, cold resistance, good chemical resistance, but its impatience strong base, easy to static electricity, yet no appropriate anti-static method, so items should be packed powder caused Note. PET heat sealing is extremely difficult, the current prices are also higher, so it rarely uses the form of a single film, mostly with good sealing of PP or PE compound, or coated with polyvinylidene chloride. This kind of PET film as substrate composite film is the ideal mechanical packaging material operation, widely used in cooking, baking and frozen food packaging, etc..
EVOH (ethylene - vinyl alcohol copolymer)
Has a very good gas barrier properties, oil resistance, organic solvent, high-gloss transparent, strong mechanical strength, thermal stability, but hydrophilic, water vapor transmission rate than LDPE large, often as a middle layer of composite membrane (Barrier Layer) widely used.
Moisture and moisture is not divided into two categories, as packaging material advantages are: high transparency, rigid, non-static, good printing, gas transmission rate is small, good gloss, not aging, good heat resistance, distortion do not bounce. Disadvantages are: brittleness, no sealing of.
AL (aluminum foil)
Packaging materials (plastic composite) the only metal substrate, has the best shade, moisture, gas barrier, preserving taste of. Disadvantages are: no folding, no sealing, corrosion easily, easily torn, not alone as packaging material, usually as a barrier layer and the other with plastic film or paper composite.
Is in a vacuum vapor deposition of aluminum accumulation in a variety of basement membrane up a film. Aluminum thickness is generally 40 ~ 70nm, vacuum aluminum is the most widely VMPET, VMCPP. After the film substrate by vacuum aluminum has a strong metallic luster, decorative excellent. And after vacuum aluminum, the right lighting and a variety of gas barrier greatly increased.
K-OOO (K-coating material)
The PVDC latex coating on BOPP, PA, PET, PT and other films, with the coating weight increased, greatly increased the variety of the barrier properties, we added the corresponding coating material known as K-BOPP , K-PA, K-PET, K-PT
As a kind of composite materials, composite materials to increase strength, reduce the flexibility of plastic, increasing the composite stiffness.
The main advantage is the low temperature heat sealing, excellent sealing together of, formability, toughness, transparency, oil resistance, solvent resistance, excellent heat sealability through contamination of PA and other important packaging AL Strong adhesion to .
M-PET (transparent aluminum PET)
Outside the PET film is coated by a layer of alumina nano-technology level, that play a UV, gas barrier functions such as aluminum foil can play, but the material is transparent, and increase the product's visual impact, making the addition of customer the kind of packaging options