What Should You Know about Thermoforming Materials?

Thermoforming is a common plastic manufacturing process method, also known as vacuum forming or pressure forming. The thermoforming process is to heating plastic sheets to a softened state, then use negative air pressure to attract the plastic sheet to the surface of the mold, and use cooling to solidify it to form.

There are several thermoforming methods used in actual production, and the most basic ones are six: differential pressure forming, overmolding, plunger-assisted molding, suction molding, countermolding, and twin sheet forming.

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Thermoforming is widely used in the manufacture of various plastic products, such as packaging boxes, toys, medical equipment, automotive interior parts, etc.

Thermoforming materials usually use thermoplastic plastics. The only raw materials are plastic sheets. Commonly used sheets include: PVC, PET, PP, PS, PET-G (GAG), PC, PE and based on this, flocking sheets, gold-plated sheets and anti-static sheets. Static sheet.

Thermoforming Material Classification

Classification According to Material Thickness

Ordinary Thin Gauge Thermoforming

Thickness is 0.14-5.0mm. Mainly using PVC, PP, PS (HIPS), PET (including APET and PETG), PE, BOPS and recyclable paper trays and other materials and effects for folding, half-folding, three-folding, cylinder, folding box and other non-thermoforming vacuum forming products are widely used in industries such as food, medicine, electronics, toys, computers, daily necessities, cosmetics, and mechanical hardware.

Special Thick Gauge Thermoforming

Thickness is 0.14-8.0mm. It mainly uses injection-molded and heavy gauge thermoforming(thick gauge thermoforming) products with various materials and effects such as PVC, PP, PS (HIPS), PET (including APET and PETG), ABS, PC, PE and PMMA.

The main products include refrigerator liners, advertising light boxes, Product display stands, pet cage chassis, rear projection TV back shells and various mechanical panels can replace injection molded products. They have low mold costs (only 1/20 of injection molds), short production cycles, and short mold development time (generally as long as 3 to 5 days) and other characteristics.

Classification According to Material Type

PP

PP sheet is made from PP resin as raw material and undergoes processes such as brewing, calendering, and trimming. It has the characteristics of light weight, bright and smooth surface, good heat resistance, high mechanical strength, excellent chemical stability and electrical insulation, and non-toxicity. After thermoforming, it can be made into beverage cups, food boxes and other daily necessities.

PP is a material with good mechanical strength and chemical stability. It has good toughness and wear resistance and is suitable for making various containers, barrels, pipes, etc. PP material is particularly soft, has good toughness, is environmentally friendly, non-toxic, and resistant to high temperatures. It is often made into packaging for dining utensils or other high-temperature resistant products. However, it has poor plasticity, difficulty in processing, poor surface gloss, and the color will become lighter during processing.

Main features:

1. It can be used for a long time at 100℃ and can withstand high-temperature bacterial treatment at 121℃.

2. It has outstanding moisture-proof performance and reliable hygienic performance. It is widely used in food packaging.

3. It has excellent folding performance and can be made into stationery clips, boxes, etc.

PVC

PVC is a common thermoplastic materials with good corrosion resistance and insulation properties. It can be divided into soft PVC and hard PVC. Soft PVC has good softness and plasticity and is widely used in wires and cables, floors, hoses, etc. Rigid PVC has high mechanical strength and corrosion resistance, and is suitable for making window frames, water pipes, doors and windows, etc.

PVC sheet is a widely used and popular material. The hard sheet has high toughness and is not easy to burn. Chlorine gas will be produced when burned, which will have a certain impact on the environment.

PVC is easy to heat seal, and can be sealed with sealing machines and high-frequency machines. , is the main raw material for the production of transparent theroforming products.

PVC sheets can be divided into environmentally friendly and non-environmentally friendly ones. PVC sheets can be made into various vacuum forming packaging such as transparent package, colorful, anti-static, gold-plated, and flocked.

Its main characteristics are high transparency, good surface gloss, few crystal points, and water content. It has small grain, wide application, strong impact resistance, and is easily formed into desired shape. The products comply with the US FDA and Japanese PL food hygiene standards.

PVC thermoforming products are widely applicated in toys, food package industry, electronic products, medicine, gifts, cosmetics, stationery and other products.

PS

PS is a common transparent plastic with good flatness and transparency. Low density (light weight), environmentally friendly and non-toxic, very good plasticity, poor toughness and brittle, so it can only be made into bottom-type blister. Because it is easy to crack, this type of thermoforming should not be recycled. PS can be divided into ordinary PS and high impact PS. Ordinary PS has high transparency and is often used to make food packaging, injection molded parts, etc. Due to its high toughness, high-impact PS is used to make products that require impact resistance, such as goggles and toys.

Main features:

1. It generates low static electricity and is suitable for packaging products that require low static electricity.

2. Easy to vacuum form, and the product has good resistance performance.

3. PS sheets have nice hygienic performance and can be in direct contact with food without producing harmful substances.

4. It is easy to color and can be made into materials of different colors to produce vacuum covers of different colors.

5. Good hardness. This kind of board has better hardness than other boards of the same thickness. Vacuum forming cups can be used as cups for hot and cold drinks.

6. It complies with environmental protection requirements and can be recycled and reused. No harmful substances that harm the environment are produced when the waste is burned.

Application:

1. Electronic products

2. Food packaging (such as: beverages, candy, and meat... packaging purposes)

3. Dairy products (dairy products packaged in polystyrene sheet containers can be placed in refrigerators and will not deteriorate easily)

PET

PET has good mechanical strength and temperature resistance. It has high transparency and good impact resistance, and is often used to make bottles, packaging containers, etc. It is hard, has good toughness, high strength, bright surface, environmentally friendly and non-toxic, and is available in transparent and various colors.

The disadvantage is that high-frequency heat sealing of PET is more difficult and the price is much more expensive than PVC sheets. PET sheets is often used as an alternative to PVC by users who want high-end, environmentally friendly products. In addition, PET can also be used to make fibers, such as polycool fiber, which is used to make clothing.

PET sheet is a new material that has been developed in recent years. With its excellent toughness, high strength, high transparency, and excellent environmental performance of being recyclable and reusable, it does not produce harmful gases when burned. It is an environmentally friendly material and has been gradually banned from PVC.

There is great confusion between consumers and producers, but the price is high. Suitable for making high-end thermoforming products, thermoforming shells in European and American countries generally require the use of PET material, but its thermal melting point is high, which brings great difficulties to high-frequency packaging.

In order to solve this problem, people laminate on the surface of PET. A layer of PVC film is named PETG, but the price is higher. Mainly used in electronics, food, toys, color box windows, collar supports, footwear packaging, etc.

PET hard sheets have good toughness, high transparency, are easy to burn, and do not produce harmful gases when burning. They are environmentally friendly materials, but are expensive and are suitable for high-end thermoforming products.

Thermoforming shells in European and American countries generally require PET hard sheets, but it is not easy to heated plastic sheet, which brings great difficulties to packaging. In order to solve this problem, people laminated a layer of PVC film on the surface of PET and named it PETG hard sheet, but the price is higher.

Main features:

1. It has excellent transparency and smoothness and good display effect.

2. Excellent surface decoration performance, can be printed without surface treatment, easy to press patterns, easy to metal treatment.

3. Has good mechanical strength.

4. Good barrier properties against oxygen and water vapor.

5. It has good chemical resistance and can withstand the erosion of various chemical substances.

6. Without toxic and reliable in hygienic performance. It can be used for packaging of food, medicine and medical equipment, and can be sterilized by Y-rays.

7. It has good environmental adaptability and can be recycled economically and conveniently.

8. The thermoforming performance is good, which is equivalent to ordinary PVC sheets. Vacuum forming process can be used to produce PET thermoformed products with excellent performance.

PET-G

PET-G is a non-crystalline PET resin modified with cyclohexanediol. The biggest advantages of PETG sheets are good heat sealing performance, easy operation during sealing, good sealing effect and easy glue bonding.

At the same time, its chemical resistance, optical properties, and scratch resistance are also very good. PETG has passed the U.S. FDA's food contact standards and can be used in food and personal health product packaging, medical and health equipment food and other fields, and can also be used in electronic device packaging.

PET-G is hard, has good toughness, high strength, and is environmentally friendly. It can be heat sealed with high frequency, but the cost is higher.

Advantages:

1. Good transparency, suitable for products requiring high transparency.

2. Excellent impact strength and rigidity.

3. Excellent processability. It can be processed by sawing, die-cutting, drilling and laser cutting. It can also be cold-bent and hot-bent, adhered, welded and polished, printed and painted, and the cold-bending does not turn white and has a bright appearance.

4. Good thermoformability, can be formed without preheating, high precision, good deep formability, no cracking and uniform thickness.

5. Low flammability, good fire resistance, no combustion support, low smoke production, no harmful substances after burning.

GAG Three-Layer Composite Sheet

GAG is a three-layer composite sheet produced by co-extrusion of the middle layer of APET and the upper and lower layers of PETG raw materials in appropriate proportions. It is especially suitable for packaging boxes that require high-frequency heat sealing and glue bonding.

Advantages:

1. Good transparency, the transparency can reach more than 90%, and the texture is good. It is suitable for products requiring high transparency.

2. Excellent impact strength and rigidity, the material is hard and durable, and suitable for high impact strength applications.

3. Excellent processability. It can be processed by sawing, die-cutting, drilling and laser cutting. It can also be cold-bent and hot-bent, adhered, welded and polished, printed and painted, and the cold-bending does not turn white and has a bright appearance.

4. It has good thermoformability and can be formed without preheating. It has high precision and a shrinkage rate of about 0.5%. Good deep formability, no cracking and uniform thickness.

5. Environmentally friendly, recyclable and does not pollute the environment.

6. Excellent food hygiene, the material is PETG, which can comply with all major food regulations, such as FDA or BGA, etc., and is suitable for food container packaging

7. It has good fire resistance, does not support combustion, produces low smoke, and has no harmful substances after burning.

PC

PC is a material with excellent mechanical properties and transparency. It has high strength, high temperature tolerance and wear resistance, and is suitable for making high-demand products such as auto parts, optical discs, and mobile phone cases.

PE

PE is a common thermoplastic material with good toughness, impact resistance and corrosion resistance. It can be divided into high-density polyethylene (HDPE) and low-density polyethylene (LDPE) and has a wide range of applications.

High-density polyethylene is mainly used to make water bottles, containers, food packaging bags, etc., while low-density polyethylene is mainly used to make plastic bags, films, and stretch films.

How to Choose Thermoforming Materials?

Thickness

The thickness of the blister material affects its ability to withstand pressure and its durability. Generally speaking, the greater the thickness, the better the quality and the higher the price.

Material

There are many kinds of blister materials, such as PET, PP, PVC, etc. Different materials have different characteristics and usage scenarios, and they need to be selected according to actual needs.

Appearance Condition

The appearance of blister materials is also a purchasing factor. You need to choose products with good transparency and flawless products.

Size

The size of the blister material needs to be selected according to actual needs to ensure that the product can be completely wrapped.

Environmentally Friendly Features

When choosing blister raw materials, environmental protection characteristics should be one of the priority factors. Environmentally friendly materials refer to materials that are eco-friendly, sustainable, and do not cause pollution to the environment or cause less pollution. In this regard, PLA biodegradable material is one of the most environmentally friendly materials currently on the market. It is recyclable and degradable and can effectively reduce the environmental pollution caused by plastic waste.

Cost Factor

The cost of environmentally friendly materials is relatively high, which is also a factor that many companies consider when choosing blister raw materials. Therefore, in addition to environmentally friendly properties, there is also a cost factor to consider. Generally speaking, the price of PP blister raw materials is relatively low, while the price of PLA biodegradable materials is relatively high, but when it comes to achieving sustainable investment, it is still very important to choose environmentally friendly materials.

Performance Characteristics

In addition to cost and environmental protection characteristics, the performance characteristics of blister raw materials are also one of the important factors in selection. For example, in some situations where thermal insulation or thermal insulation is required, EPE polyethylene foam is the first choice, while in some situations where transparency and hardness are required, PS plastic is more suitable.

Plasticity

Plasticity is also one of the important factors in choosing blister raw materials. Materials with better plasticity can better adapt to the shapes and sizes of various thermoforming products, and can ensure the beauty and accuracy of the product's appearance.

Conclusion

Thermoforming materials have good physical and chemical properties and can be selected according to different requirements. In different application fields, thermoforming materials can meet various needs and are widely used in various industries and fields.

At the same time, the selection of thermoforming raw materials should also take into account various factors such as environmental protection characteristics, cost factors, performance characteristics and plasticity.