Cosmetics packaging plastic bottles common problems

Cosmetics packaging materials such as plastic bottles are mainly made of polyethylene or polypropylene and added made from a variety of organic solvents. Cosmetics packaging plastic bottle widely used polyester ( PET) , polyethylene ( PE） And polypropylene ( PP) As raw material, after adding the corresponding organic solvent, after high temperature heating, through plastic mold after blow molding, extrusion blow or injection molding of plastic containers.

1, in the design of extrusion plastic bottles, if is made of high density polyethylene or polypropylene, plastic bottles of cross section should be rectangular or oval, low density polyethylene or other flexible material for plastic bottle, its round cross section as well. Such facilitating contents from out from the plastic bottles. Used with plastic bottle of the plastic parts mainly for cap and seal. Plastic bottle design should consider mainly, how to make a plastic bottle can better with the bottom of the cover and sealed with plastic bottles, plastic mechanics performance of weak positions. Therefore, the plastic bottle at the bottom of the general design into inside concave. Plastic bottles of the corner, and inner sunken place, all do larger arc excessive. For convenience of plastic bottles stacked, increasing the stacking stability of plastic bottles, plastic bottles should be designed at the bottom of the groove.

2, cosmetics packaging plastic surface using label, should be so that the cover is flat and level. In the surface of the plastic bottle design a 'box', make the labeling accurate positioning, do not produce movement. In blow molding, the parison swell touching part first, always tends to hardening of the first part. So the parts of the wall thickness is bigger. Edge and corner area, is the parison swell the touching part, the part of the wall thickness is smaller. As a result, the edge of the plastic bottles and wipe Angle parts should be designed as a rounded corners. Change the shape of the surface of the plastic bottle, such as plastic bottle in the middle of relatively thin some, increase the surface of the plastic bottles of circumferential grooves or convex rib, can improve the rigidity and the bending resistance of plastic bottles. Longitudinal grooves or reinforcement, can eliminate plastic bottles under long-term load migration, sagging or deformation phenomenon.

3, cosmetics packaging plastic bottle printing surface, are the most important parts of the consumers' attention. Printing surface should be smooth, continuous, if plastic bottles containing handle, grooves, the reinforced structure, such as design should pay attention to when printing operation inconvenience. Oval plastic bottles, rigidity is high, but the mould manufacturing cost is higher. So to ensure the stiffness of plastic bottles, in addition to choose the material with high rigidity, but also by the shape of the plastic bottle design, enhancing stiffness and load resistance strength of plastic bottles.

4, since most plastic with notch sensitivity, plastic bottles at the sharp corners, mouth thread roots, in areas such as the neck, prone to fracture and cracking phenomenon, so these parts should be designed with rounded corners. For the corner rectangular plastic bottles, need to support the cosmetics packaging plastic bottles, most of the load of the wall thickness, so local increase here also to increase stiffness and load resistance strength of plastic bottles.