What are the advantages of TPE/TPR toy materials?
Time：2020-06-04Hits：1788
TPR/TPE soft adhesive is modified with environment-friendly plasticizer, does not add toxic additives, does not contain halogen, and is non-toxic in combustion. ROHS-compliant, 6P\16P-free, PAHs-free, nonylphenol NP-free, bisphenol A-free, fully compliant with EU EN71-3, EN71-9, ASTM-F963 and other toy industry standards.
Advantages of TPE/TPR toy materials
01 Environmental Protection Performance
Different countries or regions still have different testing standards for toy products. Some requirements do not contain PAHs, polycyclic aromatic hydrocarbons, NP (nonylphenol), and some requirements do not contain SVHC substances of high concern specified by REACH. The above environmental protection requirements for TPR materials can be passed.
02 Excellent Color Matching and Oil Spray Silk Screen Printing Performance
Toy products are mostly brightly colored and have high requirements on the coloring property of TPR materials. A good TPR has good toner dispersion and coloring properties (manufacturers should choose elastomer soft toner) to make the color realistic. TPR also has excellent adhesion during paint spraying and silk-screen printing, so that the paint does not fall off when sprayed. Of course, the matching of TPR compound and ink and paint is also very important, and appropriate paint and ink should be selected according to the characteristics of TPR.
03 Excellent Elastic Properties and Precautions
TPE/TPR material has good flexibility, high resilience, smooth and bright surface, and is not easy to crack. Specific product requirements can be reported to TPE/TPR material manufacturers, who can adjust the formula to achieve the best results. TPR material is not recommended for products with hardness below 20 A. Products with low hardness are easy to crack. TPE series products are recommended. The hardness of TPE series can be below zero. Due to the demand of the market, the popular eraser dolls on the market can also be injection molded with low-end TPR materials. This kind of eraser doll cannot use TPR with high elasticity when selecting materials because it needs both the beauty of the doll and the ability to wipe. Generally, this kind of material will try to keep its wiping ability on the premise of ensuring that the material is easy to form.
04 Good Forming and Processing Performance
TPE/TPR material has moderate fluidity, convenient molding and processing, and the injection temperature is 170-190 DEG C. It is not easy to have molding appearance problems such as shrinkage and burrs.
TPR doll products with SBS as the main substrate should strictly control the process. It is better not to use a high-speed mixing barrel for mixing materials. It is better to use a horizontal type, and the time should not be too long. Generally speaking, the processing temperature should be controlled as low as possible. 180℃ in the shearing section and 160℃ in the following sections are sufficient. SBS above 200℃ is easy to age and its odor will also increase a lot. The TPR pellets produced should be cooled as soon as possible to volatilize the odor and ensure that there is not too much heat during packaging.
Some toy products need to be sprayed with oil on TPE/TPR materials. In fact, there are special precautions when spraying oil. Generally, the main component of paint is resin. Its function is to make the pigment adhere to the surface of rubber parts. Generally TPE paints are mainly aromatic hydrocarbons and ketones.
Main precautions for TPE/TPR injection
01 solvent reason
For common hard body materials such as ABS and HIPS, paint is usually mixed with a solvent with weak chemical properties. So as to ensure that the surface of the glue piece can be kept smooth after oil injection without damaging the physical strength.
On the other hand, general soft-bodied general plastics, such as PVC, are usually accompanied by solvents with strong chemical properties. Because the soft rubber parts will have a certain degree of deformation and extensibility, strong solvent can ensure that the paint material will firmly adhere to the rubber parts, even if the soft rubber material is deformed, it is not easy to separate.
TPE integrates the characteristics of soft glue and hard glue. If there is a problem during oil injection, it is often due to an error in solvent selection, resulting in burning and deoiling.
(1) glue burning-mainly occurs on rubber parts with TPE hardness greater than 70 degrees. due to the strong solvent used, the surface is seriously corroded and traces are left when contacting the rubber parts, i.e. glue burning occurs.
② De-oiling-mainly occurs on rubber parts with TPE hardness less than 70 degrees. Because the solvent used is too weak, the paint cannot be firmly attached to the surface of the adhesive. Once the soft rubber piece is deformed, the paint itself cannot follow the shape change, causing the surface layer to separate, causing deoiling.
02 module design
If the surface of the product is uneven, such as the doll's face, burning glue will often occur. The reason is that uneven parts usually have solvent accumulation and glue burning opportunities.
Excess ingredients in nozzle material
Manufacturers usually add different proportions of nozzle materials in their production. However, the nozzle material will reduce the chemical resistance of the glue piece. When the solvent that the pure raw material product can bear is too strong for the product containing the nozzle material, the glue burning occurs.
04 tPE containing PP or pe components
Some TPE contains PP or PE components to enhance adhesion. However, PP and PE are chemicals with strong chemical resistance, so the finished TPE products have poor oil injection performance.
Solution
(1) choose the appropriate bath agent. In general, the first cornerstone does not recommend manufacturers to prepare their own paints, but should seek assistance from professional paint suppliers.
(2) Try to design the material level as flat as possible. If the design is limited, paint should be diluted as much as possible to reduce the influence of glue burning due to solvent accumulation. (3) the amount of nozzle material is arranged below 30%. ④ TPE containing PP and PE should be avoided if there is oil injection process.
As for the solvent, it is mainly used to dilute the resin and erode the surface of the glue piece so that the glue piece has more surface area for bonding. As far as TPE paint is concerned, aromatic hydrocarbons and ketones are the main components. As for toner and additives, they provide color for the paint itself and reduce foaming.
德创化工 (edit：dechuang)
