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A Comprehensive Explanation of Gunpla's Technological Innovations | 40 Years of Evolution from Color Plastic to KPS Material

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A Comprehensive Explanation of Gunpla's Technological Innovations | 40 Years of Evolution from Color Plastic to KPS Material

Gunpla Technological Innovations Explained in Detail | 40 Years of Evolution from Color Plastic to KPS Material

Since its release in 1980, Gunpla has continued to evolve for over 40 years. Why has Bandai been able to maintain a quality that overwhelms other companies? The answer lies in the innovative technologies introduced over the decades.

The color plastic technology that eliminated the need for painting in 1983, the snap-fit that requires no glue, the layered injection that molds four colors into the size of a grain of rice, and the KPS material that considers environmental impact—this article thoroughly explains the history of the technological innovations that support Gunpla. We will trace how Bandai's technological prowess has expanded its user base and built the world's No. 1 plastic model brand.

History of Gunpla Technological Innovations - Turning Points Supporting 40 Years of Evolution

The history of Gunpla over the past 40 years is, in itself, a history of technological innovation. From its birth in 1980 to the present, Bandai has consistently been at the forefront of plastic model technology. There are three major turning points in this evolution that dramatically changed the market.

1980 - Birth of Gunpla and Initial Challenges

July 1980, Bandai released the 1/144 RX-78-2 Gundam for 300 yen. This was right after the airing of the anime

However, with color plastic technology, by using appropriate colored resin for each part, such as red, blue, yellow, and white, the color separation is already completed at the molding stage. For example, in Gundam models, the torso is white, the legs are blue, and the joints are red, molded with different resins for each color. This allows for a color scheme that closely resembles the anime without the need for painting, eliminating the step of "painting," which was the biggest barrier in plastic model production.

Why Color Plastic Technology Was Innovative

The reason color plastic technology was revolutionary is that it dramatically lowered the entry barriers for plastic models. In the early 1980s, painting skills were essential for plastic model production. Mastering brushes and airbrushes, applying paint evenly, and managing drying times—these skills posed a very high hurdle for beginners.

With the advent of color plastic technology, even elementary school students could simply take the parts out of the box and assemble them according to the instructions to complete a visually appealing Gundam model. This change had a significant impact on the market. After 1983, the demographic for Gundam model buyers expanded greatly from adult modelers to children, propelling the first Gundam model boom into a social phenomenon. The color plastic technology, which realized the new concept of "plastic models that anyone can make," became the foundation for Bandai's market dominance.

Evolution of Color Plastic Technology - The Path to Multi-Color Molding

Color plastic technology continued to evolve even after its practical application. The early color plastics were technologies for creating single-colored parts, but after the 1990s, multi-color molding technology, which molds multiple colors into a single part, was developed.

For example, in the face parts, by molding the white face section and the red chin section together, the number of parts can be reduced while enhancing the precision of color separation. This multi-color molding technology evolved into the layered injection technology mentioned later. In current Gundam models, one part can have complex color separations of three or four colors, achieving a very realistic finish without painting. The evolution of Bandai's molding technology, which started with color plastic technology, continues to this day.

Snap Fit Technology - Realizing Assembly Without Glue

Alongside color plastic technology, snap fit technology has greatly contributed to the spread of Gundam models. Introduced in earnest after 1988, this technology allows parts to be assembled without glue. Let's take a look at how snap fit technology works and the benefits it brings to beginners.

How Snap Fit Technology Works

Snap fit technology is a method of fixing parts together using a structure of protrusions and recesses. It is designed so that by simply inserting a protrusion (convex part) into a hole (concave part) at the connection point, the parts are securely fixed.

This mechanism may sound simple, but it requires extremely advanced mold technology to realize. If the dimensional accuracy of the fitting parts is poor, the parts may easily come apart or, conversely, be too tight and break. Bandai achieved a balance of appropriate holding power and ease of removal through precision mold manufacturing technology to the hundredth of a millimeter. This precise design allows parts to be securely fixed without glue, and they can be reassembled multiple times, resulting in Gundam models that are easy to work with. The background of snap fit technology is the high precision of molds, which will be discussed later.

Evolution to Beginner-Friendly Gundam Models

The greatest advantage of snap fit technology is that it allows users to enjoy plastic model making without fear of making mistakes. In traditional plastic models that use glue, once glued, mistakes cannot be corrected. If glue spills, it makes the appearance messy, and if glued in the wrong position, it cannot be undone.

However, with the snap fit method, even if there is an assembly mistake, it can be easily taken apart and reassembled. This characteristic of "being able to redo it even after a mistake" significantly lowers the psychological barrier for beginners. Additionally, the unique smell of glue and the waiting time for it to dry are eliminated, making it easier to enjoy plastic model making. By combining with color plastic technology, Gundam models have evolved into the ideal plastic model that is "no painting required, no glue required, and cannot be easily messed up by beginners."

Current State of Snap Fit Technology

The snap-fit technology continues to evolve. The cutting edge of this is the EG (Entry Grade) series that debuted in 2020. In the EG series, the snap-fit technology has been further developed, adopting the "Touch Gate" structure that even eliminates the need for nippers.

By simply breaking the parts off the runner by hand, the design minimizes the visibility of gate marks. As a result, no tools are needed for Gunpla production, allowing you to literally "open the box and assemble it by hand" to complete it. Over 30 years since the introduction of glue-free models in 1988, snap-fit technology has consistently lowered the entry barriers for beginners.

Layered Injection - The World's First Technology to Mold Four Colors into the Size of a Grain of Rice

The ultimate evolution of color plastic technology is the layered injection technology. With this world-first multi-color molding technology, Bandai has made it possible to mold four colors simultaneously into parts the size of a grain of rice. This is a groundbreaking advancement not only in the plastic model industry but also in the entire field of plastic molding technology.

What is Layered Injection Technology

Layered injection technology is a method that simultaneously injects multiple different colored resins into a mold, layering them to form a structure. In traditional multi-color molding, different colored resins are typically arranged side by side. However, with layered injection, resins are stacked vertically, achieving very fine color separation.

For example, in the eye parts of a figure, it can create a four-layer structure of white sclera → outer iris → inner iris → pupil in a single molding. The key to this technology is precisely controlling the timing and pressure of the injection to prevent different colored resins from mixing. Bandai established this control technology and began practical application around 2008 with products like the S.H.Figuarts series. It is particularly adopted in high-end lines such as RG (Real Grade) and MG (Master Grade) in Gunpla.

Precision in Reproducing Four Colors in Grain-Sized Parts

The true essence of layered injection technology is its ability to apply four colors to parts as small as a grain of rice. For instance, in the S.H.Figuarts Kamen Rider figures, the compound eye parts, which are a few millimeters in diameter, feature four colors arranged in concentric circles: outer green, middle yellow, inner orange, and center red.

To achieve this precision, not only the accuracy of the mold but also the fluidity of the resin, temperature control, and fine adjustments of injection pressure must all be perfectly controlled. In conventional plastic molding technology, color boundaries can become blurred or mixed. However, with Bandai's technology, the boundaries are clearly defined. This technological prowess is the world's first and supports Bandai's competitive advantage as a unique technology that cannot be replicated by other companies.

Expressions Made Possible by Layered Injection

Thanks to layered injection technology, the expressive power of Gunpla and figures has dramatically improved. The most notable enhancement is in the reproduction of eyes and compound eyes. Previously, it was necessary to either apply stickers to single-color parts or for users to paint them themselves, but with layered injection, complex color separation for the eyes is completed during the part molding stage.

This allows for the reproduction of realistic and lively expressions. Additionally, in Gunpla, it is also utilized for one-point markings and complex color separations on the aircraft. Layered injection technology is widely applied to movable figures like S.H.Figuarts, becoming a crucial technology that elevates the overall quality of Bandai's products. The evolution of molding technology that began with color plastic technology has reached the cutting-edge technology of layered injection.

0.01mm Mold Precision - The Technology Supporting Bandai's Quality

The color plastic technology, snap-fit technology, and layered injection technology introduced so far are all based on Bandai's mold manufacturing technology. The precision of 0.01mm, at a microscopic level, supports the overwhelming quality of Gunpla.

Why Mold Precision is Important

The quality of plastic models is almost determined by the precision of the mold. A mold is a shape into which melted plastic is poured and solidified, and if the precision of this mold is lax, the dimensions of the parts may vary, or gaps may form at the joints.

Especially in snap-fit technology, where parts are fixed by fitting into each other, even a shift of a few tens of microns can cause parts to become loose or tight. Moreover, advanced molding techniques like layered injection cannot be realized if the mold precision is low. In other words, mold precision is the most critical factor that determines the

The biggest feature of KPS material is that it is designed with recyclability in mind. While traditional PS materials were also recyclable, KPS materials are compatible with a more efficient recycling process.

Bandai has launched the "Gunpla Recycling Project" in 2021, collecting unwanted runners (the frame parts with attached pieces) at stores and promoting their reuse as recycled materials. KPS materials have properties that make them easy to regenerate in this recycling process, allowing new plastic products to be made from collected runners. Additionally, consideration is given to reducing CO2 emissions during the manufacturing process, making it an important material from the perspective of addressing the SDGs (Sustainable Development Goals). The technological innovation of Gunpla extends beyond mere quality improvement to encompass social responsibility towards the global environment.

Future Developments of KPS Material

KPS material is currently expanding its adoption primarily in the HG (High Grade) series. In the future, it is expected to be applied to higher grades such as MG and RG.

Furthermore, there are considerations for the release of "recycled version Gunpla" using resins collected from the Gunpla Recycling Project, contributing to a circular economy. KPS material symbolizes Bandai's goal of "sustainable manufacturing." With over 40 years of technological innovation history, Gunpla will continue to challenge the new issues of balancing environmental concerns and quality.

Meister System - Technical Inheritance and Human Resource Development

Ultimately, the support for cutting-edge technology comes down to "people." Since 2012, Bandai has introduced the "Meister System," establishing a framework for passing on the advanced skills of skilled technicians to the next generation. This system has made 40 years of technological innovation possible.

Mechanism of the Meister System

The Meister System is a technical inheritance program started by Bandai in 2012. It certifies veteran technicians with particularly advanced skills, such as mold manufacturing and molding technology, as "Meisters" and systematically provides technical guidance to younger employees.

To be certified as a Meister, one must have over 20 years of practical experience and pass a rigorous internal examination. Certified Meisters take on the responsibility of technical guidance in addition to their regular duties, passing on skills to young technicians on a one-on-one basis. This system ensures that skills such as manual finishing techniques for molds, understanding the flow characteristics of resins, and know-how for fine adjustments—knowledge that cannot be digitized—are reliably inherited. The source of Bandai's technological strength lies not only in the latest equipment but also in such human resource development systems.

Why Technical Inheritance is Important

Model kit manufacturing, especially mold manufacturing, is a field that requires highly skilled craftsmanship. There are many skills that cannot be fully conveyed by machines or manuals, such as finishing molds with an accuracy of one-hundredth of a millimeter and fine-tuning layered injection.

For example, in mold polishing, the craftsman judges the micro-level unevenness by hand and finishes it with the appropriate amount of force. Such skills are acquired over many years under the guidance of experienced professionals. If technical inheritance were to cease, no matter how high-performance the equipment, Bandai's quality could not be maintained. The Meister System is a strategic framework to prevent the discontinuity of such skills and ensure that the technological assets accumulated over 40 years are reliably passed on to the future.

Quality Created by the Meister System

The skills inherited through the Meister System are directly reflected in the quality of Gunpla. For instance, when creating a new mold, young technicians receive guidance from Meisters, allowing them to complete high-precision molds from the first attempt.

Moreover, during the development of new technologies, the fusion of veteran experience and young innovative ideas leads to the emergence of innovative solutions. It is because of this system of technical inheritance that Bandai has been able to continue technological innovation for over 40 years and consistently maintain the highest quality in the industry.

Conclusion: Bandai's Technological Innovation Made Gunpla World No. 1

The 40-year history of Gunpla has been a continuous series of technological innovations. The color plastic technology introduced in 1983 made it possible to eliminate the need for painting, and the snap-fit technology in 1988 achieved the elimination of glue. By dramatically lowering the barriers to entry, it expanded the user base.

Furthermore, the world's first multi-color molding technology called layered injection has gained astonishing expressive power by molding four colors into parts the size of a grain of rice. Supporting all these technologies is the mold precision of 0.01 millimeters. In the 2020s, a new environmentally friendly material called KPS has been introduced, evolving towards sustainable manufacturing.

What makes these technological innovations possible is the system of skill inheritance through the Meister system. By merging cutting-edge digital technology with the skills of skilled artisans, Bandai has achieved a level of quality that cannot be matched by other companies. "Why does Bandai's Gunpla overwhelm others?" - The answer lies in the history of technological innovations accumulated over more than 40 years.

Bandai's technological prowess supports not only Gunpla but the entire figure business, including S.H.Figuarts and ROBOT Spirits. If you want to know how Bandai built the Japanese figure market and successfully expanded globally, please refer to BANDAI and Gunpla's Achievements | The Technological Innovations and Global Expansion of the Giant Manufacturer that Created the Japanese Figure Market. By understanding the history of technological innovations, you should be able to enjoy the depth of Gunpla even more.

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BANDAI and the Achievements of Gunpla | The Technology and Global Expansion that Created the Japanese Figure Market