In the previous article (Decorating Toys: Current Methods and Future Prospects)
we talked about the various methods of toy decoration, but now I would like to show you a real-life example of the use of an inkjet printer in toy manufacturing.

Introduction to the Interviewee

Left: Tam’s Zhuhai Plant in Guangdong Province, China
Right: Mr. Tam King Hing, President

Tam's Industrial Co., Ltd. has a factory in Zhuhai, Guangdong Province, China.
Zhuhai in China has attracted many Japanese companies in the electronic circuit board and IC related industries for the past 20 years due to its location close to Hong Kong and Shenzhen and bordering Macau.

With a current workforce of around 800 people, it is not the largest toy factory in China, but it is a company with a reputation for technical excellence, manufacturing products for major Japanese toy manufacturers. 95% of their sales are to Japan and the remaining 5% to the USA, while meeting international quality standards.

Tam’s does not manufacture its own originally designed products but produces items to order from toy manufacturers in Japan and the USA. They receive 3D drawing data from their clients, and handle the entire process from molding, painting, assembly, and shipping. Although the number of factories in China that can produce die-cast products is decreasing, Tam’s main products are robots and miniature cars that use die-casting. They also produce many plastic toys, such as models, which require advanced molding techniques.

Tam’s first introduced an inkjet printer for decorating toys in 2011. As one of the first toy factories to introduce inkjet printing, so they had to make a lot of adjustments before they could begin mass production.

The inkjet printer was installed to meet a client's request to print full color illustrations using four-color (CMYK) on a model train for the Japanese market. They needed to recreate a model of a train wrapped with printed cartoon characters.

Mass Production Printing Flow

Inkjet printing is a process of uniform printing on multiple quantities of specific parts, so the initial setup is the most important. First, you need a highly accurate jig to hold the object to be printed. The Tam’s factory had a capability of creating molds, so they used CNC machines to make jigs that fit the parts perfectly. These jigs are made from thick, hard plastic sheets to prevent warping.

The train parts produced at Tam’s were printed with a quantity of 150 pieces at a time. They needed to make sure that all of them were not misaligned, so they engraved a jig to fit the shape of the back of the parts. It was also important to adjust the position of the printed data, which can take up to three or four hours for even the most experienced operator. Once all of the parts had been test printed and any misalignment corrected, the fine-tuning process was repeated five or six times, and finally about 300 parts were printed to make sure that the decoration was accurate before mass production could start.

For the workers who set the parts on the jig, aptitude is more important than skill or experience. If the part floats even slightly, misalignment will occur. If the part floats, it will touch the ink nozzle and damage it, which means it will have to be replaced, so you need to choose a worker who is good at doing this carefully.

Advantages and Disadvantages of Inkjet Printing

Before the introduction of the inkjet printer, Tam’s considered the possibility of using a pad printing method to decorate trains. However, pad printing is not suitable for multi-colors as it prints one color at a time. For example, the figures they usually produce at Tam’s would potentially require as many as 14 pad printing plates for the eye parts alone. For a colorfully decorated train, this could mean hundreds of steps. The higher the number of processes, the higher the defect rate.

Pad printing also involves the same process of fitting and printing on a jig, but the operator must also control the viscosity of the ink and the wear and tear of the pads. The risk is that if even one process fails, all the work up to that point is wasted. The standards required for toys for the Japanese market are very high and the factory uses magnifying glasses to check for printing defects that are too small to be seen by the naked eye.

Inkjet printers can be time consuming to adjust at first, but once you get that right, it offers a great advantage to reduce defects in mass production.

It is also important for the factory that the workers do not need any experience or special skills for printer operation. In China, it is now very difficult to recruit workers. The rising cost of labor is also a challenge. Therefore, they are always looking at ways to automate their factories. At Tam’s, 80% of mask spray painting and round spray painting are automated. They have also automated the gate cutting of molded products. If they can make more use of inkjet printers, they will be able to automate even more.

However, inkjet printers have the disadvantage that when printing on curved or uneven surfaces, ink splashes and rough dots are noticeable, so, at present, inkjet cannot replace all painting and printing.

Summary

China is also facing the problem of rising labor costs and the difficulty of securing skilled and quality workers. As a solution to this problem, automation is becoming more and more important, and expectations for inkjet printers are also rising. With the popularity of high-quality toys not only in Japan but also in China, it is expected that the adoption of inkjet printers in the toy industry will continue to grow.



Reported by interviewing:
Tam’s Industrial Co., Ltd.
http://www.tams.com.hk/