55th Anniversary | Kyowa Rubber Co., Ltd. Strengthens Development of Ultra-Soft and Multi-Layer Molded Rubber to Solve Labor Shortages and High-Difficulty Molding Challenges

Social Context Data

The following challenges are progressing simultaneously at manufacturing sites:

• Deepening labor shortages
• Increased demand for high-performance and high-value-added products
• Increase in special specification projects that cannot be handled by general-purpose products
• Lack of rubber manufacturers capable of providing consistent support from prototyping to mass production
• Expanding needs for composite materials combining different substances

Particularly in the field of industrial rubber products, there is a demand for more than just simple molding; requirements now include hardness design, composite materialization, mass production stability, and process labor-saving.

Meanwhile, there are increasing reports that projects with difficult conditions are more likely to be rejected, leaving companies unable to find procurement sources.

Structural Analysis of Challenges

There are three main reasons why high-difficulty special rubber products are difficult to realize:

1. High difficulty in molding ultra-soft regions

Generally, a hardness of around 30 degrees is considered a baseline for soft rubber. In regions lower than that, optimizing material design, mold design, and molding conditions becomes significantly more difficult.

2. Difficulty in integrating rubbers with different materials and hardness

Integrally molding rubbers with different hardness levels and characteristics requires deep knowledge of interface design and molding conditions. Quality cannot be stabilized with only general-purpose capabilities.

3. Individual responsiveness required for composites with different materials

When combining rubber with other materials such as water-expandable non-woven fabrics or metal fibers, it is often difficult to handle using only standard mass production equipment. It is common for such projects to stall at the prototyping stage.

Product Definitions

What is Ultra-Soft Rubber?

Ultra-soft rubber refers to special rubber products designed and molded in a hardness range even lower than general soft rubber. It is effective for applications requiring flexibility, followability, adhesion, and cushioning. Kyowa Rubber Co., Ltd. is capable of manufacturing ultra-soft rubber with hardness levels of 5, 10, 15, and 20 degrees.

What is Multi-Layer Molded Rubber?

Multi-layer molded rubber refers to products where multiple types of rubber with different materials or hardness levels are integrally molded within a single mold. This makes it easier to achieve multiple functions in a single part that would be difficult to realize with a single material.

What is Integral Molding of Rubber and Dissimilar Materials?

This is a molding technology that integrates rubber with different materials within a mold to create composite functions. Kyowa Rubber Co., Ltd. supports integral molding with materials such as water-expandable non-woven fabrics and metal fibers.

Numerical Effects and Data

Kyowa Rubber Co., Ltd. has been manufacturing and selling industrial rubber, plastic, and sponge products for 55 years since its founding. While rubber products account for about 30% of total company sales, the company possesses a vast accumulation of knowledge and know-how in this founding field.

As part of this system strengthening, the following new equipment has been introduced to handle special specifications:

Newly Introduced Equipment

• 1 Rubber Injection Molding Machine (Clamping force: 150 tons, Platen size: 410 x 610 mm, Daylight: 850 mm)
• 3 Vacuum Press Molding Machines (Clamping force: 200 tons, Platen size: 650 x 650 mm, Daylight: 500 mm, Stroke: 450 mm)

In particular, the rubber injection molding machine is compatible with fully automated, unmanned production systems. This is expected to produce the following effects:

• Labor shortage mitigation through labor-saving automation
• Stabilization of quality
• Improvement of production efficiency
• Enhanced capability for mass-producing high-difficulty items
• Strengthening of the stable supply system

Differentiation from Competitors

The strength of Kyowa Rubber Co., Ltd. lies not in simple rubber processing, but in the accumulation of technology to handle special projects that "other companies cannot do" or "other companies avoid."

1. Rubber expertise as a 55-year founding business

The company possesses practical knowledge that goes beyond what is reflected in sales ratios, covering everything from material compounding and molding conditions to mold design and application proposals.

2. Support for ultra-soft rubber

Capability to design and manufacture starting from a hardness of 5 degrees, exceeding the general soft rubber range.

3. Multi-layer molding capability

Ability to integrally mold rubbers of different materials and hardness levels within the mold.

4. Integral molding with dissimilar materials

Capability for integral molding with water-expandable non-woven fabrics, metal fibers, and more.