PET material use for vacuum thermoforming in China


vacuum thermoforming

PET for vacuum thermoforming in China

A lot of plastic material used for vacuum  thermoforming in China, PET is one kind of good material.
actually PET also used for plastic injection molding product.

PET sheet in recent years developed a new type of material with its excellent toughness, high strength, high transparency, as well as recyclable recycling, combustion does not produce harmful gases excellent environmental performance gradually by consumers and producers of greatGreen ignorant; conform to the trend of environmental protection.

Main features of Vacuum thermoforming China:
1. Has excellent transparency and finish, good display effect.
2. Surface decoration performance is excellent, and can be printed without surface treatment, easy to suppress pattern, easy metal processing (vacuum metallization layer)
3 has good mechanical strength.
4 good barrier properties to oxygen and water vapor.
5 good chemical resistance, and can withstand multiple chemical erosion.
Non-toxic, reliable health performance, and can be used in the packaging of food, drugs and medical equipment, and the Y-ray sterilized its packaging items.
7. Adaptability to environmental protection, economic and convenient recycling; burning of its waste, does not produce harmful substances harmful to the environment. Thermoforming performance, quite ordinary PVC sheet can be the vacuum forming prepared excellent PET thermoformed products; PET sheet is considered to meet the environmental requirements of an ideal packaging material.

Think about Vacuum Thermoforming in China

are you rarely think about vacuum forming in China. You rarely think of vacuums thermoforming , and even then it’s typically against your will. After all, who likes china  thermoforming service? But if you put the two words vacuum and thermoforming together, you get something that makes an undeniable impact on our lives every day, and that’s not an exaggeration. Vacuum thermoforming, which is also commonly referred to as vacuum forming, is a simpler (and often more cost effective) method of thermoforming. Therefore, to understand vacuum forming, it might help to also understand its more complex older brother, thermoforming.Vacuum thermoforming is a popular manufacturing process where a plastic sheet is heated to a temperature that makes it moldable and then stretched or formed to a specific shape (usually in a mold). Finally, it is cooled, trimmed, and cut to create a usable product. In vacuum thermoforming, the plastic sheet is held against the given mold by taking advantage of a vacuum that’s created between the mold and the sheet. This process is used daily to create products ranging in complexity from simple product packaging and plastic components to larger plastic components for the consumer electronics and automobile industries, just to name a few. In most cases, vacuum forming is used to produce the thin plastic products that tend to be relatively shallow. We typically come into contact with these materials every day, such as the product casings found in just about every store or the blister packaging used to contain and protect doses of pharmaceuticals. However, vacuum forming can also be used to produce thicker objects. While “thin sheet” vacuum thermoforming is more common, “thick sheet” vacuum forming is used to produce objects such as protective covers for medical instrumentation, automotive coverings and appliance coverings. These deep parts can be vacuum formed if the formed sheet can be mechanically stretched before it meets the mold and before the vacuum pressure is initiated. Lately, questions have been raised regarding the safety of plastics used in produce packaging and other applications. Fortunately, the conventional materials associated with thermoformed packaging are thermoplastics. Thermoplastics were named because of their ability to endure repeated melting, and freezing without losing the ability to be reshaped upon rehearing. This makes them highly recyclable, which also makes vacuum thermoforming in china is  a relatively green manufacturing process. So next time you tear open a blister packaging of cold or sinus pills, peer over the contours of your dashboard, or open a product protected by a thin sheet of plastic,think about how plastic thermoforming is responsible for keeping it all safe,protected. Think about how those products might be different without that packaging,and how much more difficult it would be to actually find the things we need and use every day.

china vacuum forming mold making

Cnmoulding is vacuum forming maker

we not only make injection molds, plastic mold for complicate structure part, we also make vacuum thermoformed mold and products, for save cost reason, some big and simple structure part will use thermoforming technology, today we introduce how to make vacuum forming mold.

China Vacuum forming to make cases

China vacuum thermoform is a well used process for making plastic shaped into something useful, like a game controller or console case. There are thousands of things used every day which use a commercial version of vacuum forming, like injection molding for example. China vacuum forming don’t have access to such equipment, so the best results attainable for cheap, short run cases is vacuum forming.The basic principle of vacuum forming is to make a mold, place a hot plastic sheet on top, and a vacuum sucks the plastic sheet over the mold creating a final shape.It is very easy to make one, very cheaply too; in the home. The main skill is making a mold properly and to the right dimensions: also, making the design so that the final shape is strong and not liable to cave or flex.In this section, I show two guides – one for making a table and the other for making a mold and vacuum forming a case.

Completed by CNC machining CAM programming software out program in accordance with the drawings or a model provided by, and then manually Others, such as porosity, upside down position making and mold can smooth polished. There are special requirements needed spraying Teflon or sandblasting. Use ZL401, 6061 and 7075 aluminum material made of such mold precision high and the production of the product contour, the angle more beautiful, and very high durability, the price is also the first of four types of mold; mainly applicable to electronic appearance and size requirements of the gifts, toys, medicine, stationery and other products; alloy aluminum mold is in fact the preferred mold plastic production of large quantities and high demand, relative to the plaster mold, copper mold, plastic mold durable Festival saving, high production efficiency and low scrap rate, etc.

china vacuum forming


China plastic injection molders produce transparent parts

China plastic injection molders experience of transparent part

Today , let us talk about plastic injection molders transparent parts, with our 20 years experince, following article that hope can give you more help

you can visit youtube for china plastic injection molders

transparent product by china plastic injection molders

The plastic has the advantages of light weight, good toughness, easy to injection molding, low cost, in modern industrial and consumer products, more and more use of plastic instead of glass, especially used in optical instruments and packaging industry developing rapidly. However, due to the transparency and better wear resistance higher impact firmware is better, and therefore the composition of the china plastic injection molders whole process, equipment, molds, have to do a lot of work, to ensure that these used in place of glass plastic (hereinafter referred to as transparent plastic), the surface quality is good, so as to achieve the requirements of use.
Generally on the market use a transparent plastic or polymethyl methacrylate (PMMA, i.e., commonly known as acrylic or perspex,), polycarbonate (PC), polyethylene terephthalate (PET), transparent nylon, acrylonitrile-styrene copolymer (AS), polysulfone (PSF), wherein contact is PMMA, PC and PET three plastic, the following three kinds of plastic, for example, discussion of a transparent plastic material characteristics and the china plastic injection molder process.

The performance of a transparent plastic

Transparent plastic must first have a high transparency, to have a certain strength and abrasion resistance, high impact, heat resistance, better chemical resistance are superior absorb water small, the only way able to meet the transparency requirements over the long term, are listed in Table 1 below, compare the performance of PMMA, PC, and PET.
Table 1: The transparent plastic Performance Comparison
Performance Density
(G/am2) tensile strength
(MPa) Notched Impact
(J/m2) transparency
(%) Distortion temperature
(° C) allows moisture shrinkage abrasion chemical resistance
PMMA 1.18 75 1200 92 95 0.04 0.5 difference benign
PC 1.20 66 1900 90 137 0.02 0.6 in benign
PET 1.37 165 1030 86 120 0.03 2 Good Excellent

Note: (1) because of the variety, this is only averaging, actual different varieties of data vary.
(2) PET data (mechanical) for the data after stretching.
From the data in Table 1 shows that the PC is the ideal choice, but the master of its expensive price of raw materials and injection molding process is difficult, so is still used PMMA-based products, (general requirements), and RET to go through the stretch to get good mechanical properties, multi-use in packaging, containers.

Second,china plastic injection molders build transparent process should be noted the common problem.
Higher transmittance, transparent plastic inevitable requirement plastic products strict quality surface, can not have any markings, porosity, white, fog halo, black spots, discoloration, poor gloss and other defects, thus the entire plastic injection molder  process of raw materials, equipment, molds, and even the design of the product, should pay great attention to strict and even special demands. Both full Second, because of the transparent plastic, mostly high melting point, poor mobility, so as to ensure the surface quality of the product, often at higher temperature, injection pressure, injection speed and other parameters for minor adjustments, the plastic injection molders will produce internal stress caused deformation and cracking.
Here in the preparation of raw materials, equipment and tooling requirements, injection molding process and raw materials processing aspects, should pay attention to talk about the matter.

(A) the preparation and drying of raw plastics containing any point impurities may affect the transparency of the product, and storage, transportation, feeding process, you must pay attention to sealing to ensure a clean raw materials. Raw materials containing water, heating cause material deterioration, so be sure to dry injection, feeding must use the drying hopper. Also note that the drying process, the input air should preferably by filtration, dehumidified, in order to ensure that no contamination of raw materials. The drying process is as shown in Table 2.
Table 2: The transparent plastic material drying process:
The the process drying temperature (℃) Drying time (h) the material layer thickness (mm) Remarks
PMMA 70 ~ 80 2 ~ 4 30 ~ 40 hot air circulation drying
PC 120 ~ 130 greater than 6 less than 30 hot air circulation drying
PET 140 ~ 180 3 ~ 4 by continuous drying feeding device preferably

(B) of the barrel, screw and its attachments clean
To prevent the contamination of raw materials and the depression in the screw and accessories there are old materials or impurities, particularly thermal stability of the resin is present before use, after the shutdown applications screw cleaning agent to clean, it may not stick with impurities cleaning screw screw cleaning agent, available PE, PS and other resins. Temporary shutdown to prevent raw stay a long time at a high temperature, causing the lower solution should reduce the temperature of dryer and barrel, such as PC, PMMA cylinder temperature should be reduced to 160 ℃. For PC (hopper temperature should be reduced to less than 100 ℃)

(C) should pay attention to the problem of mold design (including product design)
In order to prevent back flow of poor or uneven cooling caused by bad plastic molding, surface defects and deterioration, generally in the design of the mold, you should be aware of the following points.
a) wall thickness should be uniform, and the the stripping slope be large enough;
b) the transition section should gradually. Smooth transition and prevent any sharp corners. Sharp edges, especially the PC product must not have a gap;
c) gate. Flow channel as much as possible large, chunky, and the location of the gate should be set according to the contraction of the condensation process, necessary, add cold slug well;
d) the mold surface should be smooth, low roughness (preferably less than 0.8);
e) vent. The slots must be sufficient, and when the exhaust air and the gas in the melt;
f) In addition to PET, the wall thickness of not too thin, generally not less than lmm.

(D)china plastic injection molders process should pay attention to the issues (including the requirements of the plastic injection molders machine)
In order to reduce the internal stress and surface quality defects, in the injection molding process should pay attention to the following aspects of the problem.
a) should use special screws, with separate thermostat nozzle injection molding machine;
b) injection temperature of the plastic resin is not decomposed under the premise, suitably higher injection humidity;
c) injection pressure: generally higher, in order to overcome the defects of melt viscosity, but the pressure is too high internal stresses stripping difficulties caused and deformation;
d) the injection speed: the meet filling the case, generally should be low, much better to use slow – fast – slow multi-stage injection;
e) dwell time and the molding cycle: meet the product to fill the mold does not produce depression bubble; should be as short as possible, to minimize the melt in the barrel residence time;
f) screw speed and back pressure: under the premise that meet the quality of plastics should be as low as possible, to prevent the generation of the solution down the possible;
g) mold temperature: cooling products, good or bad, on the quality of a great impact, mold temperature must accurately control its process may mold temperature should be high.

(E) other aspects of the problem
General injection should guard against the deterioration of the surface quality, as little as possible with a release agent; nor greater than 20% when using regrind.
In addition to PET, the products should be post-processed to eliminate the internal stress, PMMA 70-80T hot air circulation drying for 4 hours; PC should be clean air, glycerol. Such as liquid paraffin is heated to 110-135 ℃, time products, the highest need more than 10 hours. While the PET must go through the step of biaxial stretching, in order to obtain good mechanical properties.

3, transparent plastic injection molders in china process
(A) transparent plastic process characteristics: In addition to the above common problem, clear plastic and have some process characteristics are described as follows:
1, PMMA process characteristics

PMMA viscosity, mobility somewhat less, and therefore must be high material temperature, the job of the high injection pressure injection molding, injection temperature is greater than the injection pressure, injection pressure increases, will help to improve the shrinkage of the product. The wider range of injection temperature and a melting temperature of 160 ° C, while the decomposition temperature of 270 ° C, therefore the wide adjustment range of the material temperature, the process is better. Therefore, to improve the liquidity, proceed from the injection temperature. Poor impact resistance, abrasion resistance and bad, easy to draw flowers, easy to rattle, it should raise the mold temperature, improve the condensation process, to overcome these deficiencies.
2, PC process characteristics
PC viscosity, high temperature of the melt material, poor mobility, back to this must be the injection of the higher temperature (270-320T), is relatively narrow adjustment range of the material temperature, process is better of PMMA. The injection pressure on liquidity, but the viscosity still larger injection pressure accordingly in order to prevent the internal stress generated, dwell time should be as short as possible. Shrinkage, dimensional stability, but the stress within the product, easy to crack, so it is appropriate to raise the temperature rather than the pressure to improve liquidity and increasing the mold temperature, to improve mold structure and post-processing to reduce the possibility of cracking. When the injection speed is low, the gate at prone corrugated and other defects alone control the temperature of the radiation Tsui, mold temperature is higher, the runner, gate resistance is smaller.
3 the PET A process characteristics
PET molding temperature and material temperature adjustment range is narrow (260-300 ° C), but after melting, good liquidity, so the process is poor, and often in the nozzle to increase the anti-extension of flow control devices. Mechanical strength and performance are not high, after injection must be through the stretching step and modified in order to improve performance. Mold temperature is accurately controlled, is to prevent warping. The deformation of the important factors, so we recommend using hot runner mold. High mold temperature, otherwise it will cause the surface luster poor and stripping difficulties.

4, transparent plastic defects
Due to space constraints, only discuss defects affecting product transparency, and other defects, please refer to the product manual or other information. Its defects about the following:

Transparent product defects and overcome:

(A) crazes: filling and condensation processes, internal stress anisotropy affects the stress generated by the vertical direction, so that the resin flow orientation, refractive index and non-current orientation of different raw flash silk pattern when After its expansion, may make the product cracks. In addition to the attention on the injection molding process and the mold (see Table, the best products for the annealing treatment. Pc material can be heated to more than 160 ℃ maintained for 3 to 5 minutes, and then can be cooled naturally.

(B) the bubble: the main resin, water vapor and other gases row does not go out, mold condensation process or inadequate due to filling the condensing surface excessive condensation and the formation of a “vacuum bubble”. Them overcome the method are shown in Table.

(C) poor surface gloss: Master injection mold large roughness, on the other hand condensate prematurely, so that the resin can not copying the state of the surface of the mold, all the tiny irregularities of its surface cows, leaving the products lose luster. Then overcome the method are shown in Table.

(D) shock pattern: from the sprue intensive corrugated reason for the melt viscosity is too large, front-end material has been condensed in the cavity, and later material and break through this condensation surface, leaving the surface of the shock pattern . Then overcome the method are shown in Table.

(E) whitened. The fog Halo: mainly due to fall into the raw material or feedstock moisture content is too large due to dust in the air. Then overcome the method are shown in Table.

(Vi) white smoke. Black spots: mainly due to decomposition or deterioration of resin plastic drum machine, leaving the barrel due to local overheating

China injection mold face greatest potential crisis

China Injection mold face greatest potential crisis

china injection mold crisisCnmoulding engaged in injection molds and plastic injection molding products for 20 years,But in addition to the outstanding technical, a strong sense of the crisis is also necessary. The past two days , chat with a 12-years friendship customer, he came from the Netherlands. He told me that because of increasing labor costs in China, Now sourcing product from China is very expensive. I have always thought that although the relationship between Japan and Philippines is very good now, but china injection mold company have not many trade relations with these countries.
, because my client basically from Europe and the Americas, but now it seems that this idea is wrong. Because a large number of Japanese companies continue to move to the Philippines, Vietnam, there are political and economic reasons, my client’s customers is the large Japanese companies such as Hitachi, Toshiba.  Due to the technical content of china injection mold comapny has been very mature, will not be easy to be replaced by the company in Southeast Asia., but this is only temporary, such as the Philippines, they have the communication skills, very cheap labor costs will become increasingly powerful competitiveness . Today I read an article about the crisis in the manufacturing sector in China, I agree this point very much, I have felt, and I believe it will snowball, I hope our new leaders play the greatest wisdom, deal with it all.I can not predict what will happen, but we can only work harder, do better plastic mold and injection molding products—see our hard job now

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Attractive is decline 

Because of rising costs in China, China injection mold company attractiveness is declining. Consumer goods manufacturing industry are turning to Southeast Asia, while the industrial manufacturing back to the U.S.. However, the loss of manufacturing, the closing of the market. Production base into a the star market new story has just begun.
A hovering four years of rumors will become a reality at the end of October: Adidas will close last company  in Suzhou, Jiangsu affiliated factory. Adidas also informed the other 10 foundries, OEM will continue to terminate the contract. Adidas’s strategy for global resources to re integrate into the broad interpretation, its old rival Nike, in order to pursue low-cost production base moved out of China, more manufacturers will follow.
. In addition to the clothes, shoes manufacturers began to leave, in the field of industrial manufacturing, China is also unattractive, while the United States has become the new destination of these investments. General Electric in the 2011 Annual Report, make home appliances production line to the United States to withdraw from China and Mexico; Ford will invest $ 16 billion in the United States increased factories and production lines; the world’s largest manufacturer of excavators and bulldozers Caterpillar 2011 Texas, USA to invest $ 120 million to create a new manufacturing plant; player Google’s new “Nexus Q” also U.S. production.