PRM-TAIWAN
Issue 24 Subscribe Now

The Key to Open New Idea of Insert Molding Machine


Announcement for the innovative process of One Stage IMD+ IMF 
 
The emerge of in-mold decorating injection molding can be described as the revolution of the surface appearance decoration for plastic products. In the past IMR, IML have breakthrough improvement on product’s surface wear-resistance, ink choices, environmental concerns and color definition. However, when entering the manufacturing process of IMF+ IMD, the high defective rate impedes the manufacturers to improve the quality and lower the cost, even hesitate to advance forward.
 
Analysis why manufacturers have not been able to lower the defective rate? 
After an in-depth analysis, we sum up the following five causes:
 
1.Defects on the Film manufacturing process:
a.During thermoforming, when the substrate have poor extensibility, causing uneven thickness on the corners.
b.Difficult to control shrinkage allowance in different shapes or mechanical designs.
c.Bonding strength of surface heat treatment and hardness are unable to meet the requirement.
 
2.limited Ink Supply in the printing process:
a.Most of the high temperature resistant, impact-resistant printing inks are trade by the suppliers from developed countries, which are difficult to obtain. 
b.Involves different areas of expertise, difficult to integrate them all.
 
3.Defects on the compression molding of IMF:
a.Heat is being transferred in conventional compression molding machine, heat is lost prior to compression molding.  Resulting non-uniform thermo conductivity.
b.The mold is heated above the softening temperature during forming, causing residual stress and warpage when the film is being taken out.
 
4.Difficult to control the allowance for the trimming size:
a.The film is warpage, unable to match the flat surface of the die cut.
b.The round corners shrink after the folding; the film is stretched after injection and is too short to cover the plastic cover edge.
 
5.Too many variables in IMD injection molding.
a.There are impurity penetration, static interference and poor position tolerance during the transfer of trimmed film to the cavity.
b.Trimmed Film does not attach to the die surface; the round corners are crushed or formed by the impact of the resin. 
c.Molding conditions are complicated, bubble, flow mark, poor adhesion, rinse out ink are very common.
 
Innovation Announcement
Looking at the above-mentioned factors is understandable why it’s not easy to lower the defective rate.  What happened is that even knowing it’s a good manufacturing process but processors are still reluctant to go into mass production.
 
Base on the spirit of innovation in research, Taiwan Kinki had invested substantial amount of human and material resources and time, developed One-Stage IMF + IMD process as the one-time solution to the above-mentioned defective causes, it integrates chemical, extrusion, printing, mold, molding and other different areas of expertise, combining the traditional IMF and the IMD process into one, greatly improved the product yield and variety, so as to sharing this announcement with the industry, we are move towards the new era of exterior decoration technology for plastic products. 
 
One-Stage manufacturing process description:
IMF+IMD one stage machine employs double clamping system with rotary table, the front part is IMF process, after preheating and uniform temperature directly compression molding, The mold is heated below the softening temperature of the film.  The film stays in the mold after molding, turn directly to the rear part of IMD injection molding, after the whole process is completed, the scrap is cut and removed along the extensive edge of plastic cover.
 
The film is pre-heat and does not transfer; there is no heat loss or uniform temperature.  Since the film goes directly to injection without leaving the mold, there are no problems such as static impurity, position tolerance, and latent strain.  The film is cut along the cover, no short wrapping or overflow.  After two years of testing with films of different materials and thickness and different kinds of printing ink, we have accumulated a complete molding parameters and experience which can serve as the manufacturing process for standardized production.  Hope it would benefit the processors to reduce costs so that consumers admire cool products.