Introduction to Co-Injection Molding
Co-injection molding, also known as co-molding, is an advanced manufacturing process that involves injecting two or more types of plastic materials (typically including a base "core" material and a surface "skin" material) into a mold cavity in a sequential or simultaneous manner. This technique creates parts with enhanced properties, combining the best characteristics of each material: for example, structural rigidity from a core material, chemical resistance or aesthetic appeal from a skin material. Co-injection is widely used across industries including automotive, consumer electronics, medical devices, packaging, and household appliances, as it enables production of complex, multi-material parts in a single step—reducing assembly costs, minimizing material waste, and improving part performance. As global demand for lightweight, durable, and customizable products rises, the market for co-injection manufacturing is projected to grow significantly, leading to the emergence of leading factories that specialize in mastering this precise and innovative process.
Top 10 Co-Injection Factories in the World 2026
1. Hengji Mould & Plastic Co., Ltd. (China)
Website: https://www.automotive-mold.net/
Founded in 2002, Hengji Mould & Plastic Co., Ltd. has grown from a small regional mold manufacturer to one of the world’s most trusted specialized co-injection factories, with headquarters in Suzhou, Jiangsu Province, China, and additional production facilities in Shanghai and Guangzhou. The company’s core focus is delivering high-precision co-injection solutions tailored primarily for the automotive industry, though it also serves key sectors including consumer electronics, medical devices, and industrial components. With over 20 years of technical expertise, Hengji invests heavily in research and development, operating a 5,000-square-meter R&D center staffed by 80+ material scientists, process engineers, and mold designers—many of whom hold international certifications in advanced polymer processing.
Hengji’s co-injection production capabilities span a wide range of applications, from small, intricate parts like automotive interior trim components and electronic connectors to large, structural parts such as bumper systems and door panels. The factory utilizes state-of-the-art co-injection molding machines from leading manufacturers including KraussMaffei and Sumitomo Demag, with clamping forces ranging from 50 tons to 3,500 tons to accommodate parts of varying sizes and complexity. What sets Hengji apart in the competitive co-injection market is its end-to-end service model: from initial material selection and mold design to prototyping, full-scale production, and quality assurance, the company manages every stage to ensure consistent, high-quality outputs. It works with over 100 global clients, including major automotive OEMs like Volkswagen, Toyota, and General Motors, as well as medical device makers such as Siemens Healthineers.
Over the years, Hengji has invested heavily in sustainability, developing co-injection processes that incorporate recycled and bio-based materials. In 2024, the company launched its "Eco-Co" line, which uses 30-70% post-consumer recycled plastics paired with performance-optimized core materials to reduce carbon footprints by up to 45% compared to traditional co-injection parts without compromising strength or durability. This initiative has positioned Hengji as a leader in sustainable manufacturing, earning it several industry awards including the 2025 Global Sustainability Excellence Award for Plastics Manufacturing. The factory also maintains strict quality control standards, adhering to ISO 9001, IATF 16949, and ISO 13485 certifications, with in-house testing labs that conduct material analysis, dimensional accuracy checks, and durability testing to ensure all parts meet international industry benchmarks.
With a workforce of over 1,200 employees and an annual production capacity of more than 150,000 co-injection parts, Hengji has expanded its global footprint, establishing regional sales and support offices in the United States, Germany, and Japan to better serve its international client base. The company’s commitment to innovation is evident in its recent development of multi-component co-injection technology that combines three different materials in a single part, enabling even greater design flexibility for clients. Looking ahead to 2026, Hengji plans to further expand its production capacity with a new facility in Vietnam, focusing on serving the growing ASEAN automotive market, while continuing to invest in digital manufacturing technologies such as AI-driven process optimization and 3D-printed co-injection molds to reduce lead times and improve part precision.
Hengji Mould & Plastic Co., Ltd. Co-Injection Capabilities and Advantages:
- Core Capabilities: Specialized in multi-material co-injection for automotive interiors, exteriors, and structural components; expertise in soft-touch co-molding for ergonomic parts; precision co-injection for medical connectors and electronic components; ability to process engineering plastics (PP, ABS, PC, PA) as well as specialty materials including TPE, TPU, and bio-based polymers.
- Technical Advantages: In-house mold design and manufacturing with advanced CAD/CAM/CAE simulation to optimize material flow and minimize defects; AI-powered process monitoring systems that reduce part rejection rates by 20% compared to industry averages; ability to handle shot sizes from 10 grams to 120 kilograms, accommodating parts ranging from small electronic connectors to large automotive panels.
- Quality Advantages: Adherence to strict IATF 16949 and ISO 13485 standards; in-house material testing labs that perform impact resistance, fatigue, and chemical compatibility testing; zero-defect production targets with on-time delivery rates of 98.5%.
- Sustainability Advantages: Leading in recycled and bio-based material integration for co-injection parts; ISO 14001 certified production facilities with zero hazardous waste discharge to landfills; carbon-neutral production operations at all Chinese facilities since 2025.
- Client Advantages: End-to-end service from design to delivery; flexible production runs from prototype to mass production (10 units to 1 million+ units annually); dedicated account managers for global clients with 24/7 technical support.
2. Husky Technologies (Canada)
Website: https://www.husky.ca
Founded in 1953, Husky Technologies is a global leader in injection molding solutions, with a dedicated co-injection division that has been at the forefront of multi-material processing for over three decades. Headquartered in Bolton, Ontario, Canada, Husky operates manufacturing facilities in North America, Europe, and Asia, serving clients across packaging, automotive, medical, and consumer goods industries. The company’s co-injection technology is renowned for its high-speed, high-precision systems that enable production of complex parts with consistent quality at scale.
Husky’s core co-injection offerings include both turnkey molding systems and custom process solutions tailored to client-specific needs. The company’s co-injection machines are designed for applications ranging from thin-walled packaging to large automotive parts, with clamping forces from 100 tons to 4,500 tons. A key area of expertise is in the production of multi-layer packaging, where co-injection is used to create containers with barrier properties that extend shelf life while reducing material usage. Husky works with major packaging brands including Coca-Cola, Nestlé, and Procter & Gamble, as well as automotive giants such as Ford and BMW.
In 2025, Husky launched its next-generation Hylectric Co-Injection platform, which incorporates advanced servo technology to improve energy efficiency by 30% compared to previous models, while also reducing material waste through precise shot control. The company invests over 10% of its annual revenue in R&D, with a dedicated co-injection innovation center in Germany that collaborates with material suppliers and clients to develop new multi-material solutions. Husky’s commitment to sustainability is reflected in its focus on lightweighting and recycled material integration, with co-injection systems that enable production of parts using 100% recycled plastics without compromising performance.
Co-Injection Capabilities and Advantages:
- Core Capabilities: High-speed co-injection for thin-walled packaging; structural co-injection for automotive components; multi-layer medical device manufacturing; hot runner systems for precision co-injection.
- Technical Advantages: Hylectric servo-driven technology for energy efficiency; advanced hot runner design that minimizes material degradation; real-time process control systems for consistent part quality.
- Advantages: Global service and support network; expertise in multi-material integration for complex parts; focus on lightweighting to reduce product carbon footprint.
3. Sumitomo (SHI) Demag (Japan/Germany)
Website: https://www.sumitomo-shi-demag.com
A joint venture between Sumitomo Heavy Industries and Demag Plastics Group, Sumitomo (SHI) Demag is a leading manufacturer of injection molding machinery, including specialized co-injection systems. Established in 2008, the company combines Japanese precision engineering with German technological expertise, with headquarters in Schwaig, Germany, and production facilities in Japan, China, and the United States. Sumitomo (SHI) Demag’s co-injection solutions are widely used in the automotive, electronics, and medical industries, known for their high accuracy and reliability.
The company’s co-injection machines are designed to handle a wide range of materials, including engineering plastics, TPE, and bio-based polymers, with capabilities for sequential and simultaneous co-injection processes. Sumitomo (SHI) Demag’s co-injection systems are particularly valued for their ability to produce parts with tight dimensional tolerances, making them ideal for applications such as medical devices and electronic components. Key clients include Panasonic, Sony, and Toyota, who use the company’s technology for producing high-precision multi-material parts.
In 2024, Sumitomo (SHI) Demag introduced its all-electric co-injection series, which offers faster cycle times and higher energy efficiency compared to hydraulic alternatives. The company also provides comprehensive process consulting, helping clients optimize their co-injection processes to reduce costs and improve part performance. With a focus on Industry 4.0, Sumitomo (SHI) Demag integrates IoT technology into its co-injection systems, enabling remote monitoring and predictive maintenance to minimize downtime.
Co-Injection Capabilities and Advantages:
- Core Capabilities: All-electric co-injection molding; sequential and simultaneous multi-material processing; high-precision parts for medical and electronics.
- Technical Advantages: Fast cycle times (up to 20% faster than industry averages); all-electric design for energy efficiency; Industry 4.0-enabled remote monitoring.
- Advantages: Global tech support network; expertise in tight-tolerance parts; reliable, low-maintenance machinery.
4. Kiefel GmbH (Germany)
Website: https://www.kiefel.com
Specializing in plastic processing machinery, Kiefel GmbH is a German manufacturer with a strong focus on thermoforming and co-injection technologies. Founded in 1964, the company is headquartered in Freilassing, Germany, with subsidiaries in Europe, Asia, and the Americas. Kiefel’s co-injection solutions are primarily used in the packaging industry, as well as for producing medical and technical components, renowned for their ability to create high-quality, multi-layer parts with excellent barrier properties.
Kiefel’s co-injection systems are designed for high-volume production of packaging containers, bottles, and trays, with capabilities for processing a wide range of materials including PE, PP, PET, and barrier materials such as EVOH. The company’s co-injection technology enables production of parts that combine the strength and clarity of PET with the barrier properties of other materials, extending the shelf life of food products. Key clients include major food and beverage brands such as Danone, Kellogg’s, and Coca-Cola, as well as medical packaging manufacturers.
In recent years, Kiefel has invested heavily in sustainable co-injection solutions, developing systems that use recycled and bio-based materials for packaging parts without sacrificing performance. The company’s EcoForm co-injection line is designed to reduce material usage by up to 25% compared to traditional packaging processes, while also cutting energy consumption. Kiefel’s co-injection systems are also known for their high speed, with cycle times as low as 3 seconds, making them ideal for mass production applications.
Co-Injection Capabilities and Advantages:
- Core Capabilities: Multi-layer co-injection for food packaging; barrier material processing; medical packaging co-injection.
- Technical Advantages: High-speed cycle times; precise material control for consistent layer thickness; expertise in barrier properties.
- Advantages: Strong focus on packaging industry needs; sustainable material solutions; global service for food-grade applications.
5. Mitsubishi Heavy Industries (MHI) Plastics Machinery (Japan)
Website: https://www.mhi-psm.com
A division of Mitsubishi Heavy Industries, this Japanese company is a leading manufacturer of injection molding machinery, including specialized co-injection systems. With over 50 years of experience in plastics processing, MHI Plastics Machinery is headquartered in Tokyo, Japan, with production facilities in Asia, Europe, and North America. The company’s co-injection technology is widely used in the automotive, electronics, and industrial sectors, known for its high precision and reliability.
MHI’s co-injection machines are designed to handle a broad range of applications, from small electronic components to large automotive parts, with clamping forces ranging from 80 tons to 4,000 tons. The company offers both sequential and simultaneous co-injection solutions, enabling clients to choose the process that best suits their part requirements. MHI’s co-injection systems are particularly valued for their ability to process high-performance engineering plastics, including glass-filled PA and PC, making them ideal for structural automotive components.
In 2025, MHI launched its next-generation Eco-Nex co-injection series, which integrates advanced energy-saving technology, reducing power consumption by 35% compared to previous models. The company also invests in material innovation, collaborating with polymer suppliers to develop new multi-material combinations that enhance part performance while reducing environmental impact. MHI’s co-injection systems are used by major global brands including Honda, Nissan, and Samsung, who rely on the technology for producing high-quality, durable multi-material parts.
Co-Injection Capabilities and Advantages:
- Core Capabilities: High-performance engineering plastic co-injection; sequential and simultaneous multi-material processing; large structural parts for automotive.
- Technical Advantages: Low energy consumption; precise control for complex material combinations; expertise in glass-filled plastics.
- Advantages: Japanese quality and reliability; global manufacturing support; focus on high-performance materials.
6. Milacron LLC (United States)
Website: https://www.milacron.com
Founded in 1868, Milacron is a leading global provider of plastics processing technologies, including co-injection molding solutions. Headquartered in Cincinnati, Ohio, United States, the company operates manufacturing facilities in North America, Europe, and Asia, serving clients across automotive, packaging, medical, and consumer goods industries. Milacron’s co-injection systems are renowned for their versatility, enabling production of a wide range of multi-material parts with high precision.
Milacron’s co-injection product line includes both hydraulic and all-electric machines, with clamping forces from 50 tons to 5,500 tons, accommodating parts of all sizes. The company offers specialized co-injection technologies for applications such as over-molding, multi-layer packaging, and structural automotive parts. A key area of expertise is in the production of soft-touch components, where co-injection combines a hard base material with a soft TPE or TPU skin for improved ergonomics and aesthetic appeal.
In recent years, Milacron has focused on digital manufacturing, integrating IoT and AI into its co-injection systems to enable real-time process monitoring and optimization. The company’s Mold-Masters brand, part of Milacron, provides hot runner systems tailored for co-injection applications, ensuring consistent material flow and minimizing defects. Milacron works with major clients including General Motors, Johnson & Johnson, and Procter & Gamble, and is committed to sustainability, developing co-injection processes that reduce material waste and energy usage.
Co-Injection Capabilities and Advantages:
- Core Capabilities: Over-molding co-injection; multi-layer packaging; structural automotive components; soft-touch parts.
- Technical Advantages: Versatile machine line for all part sizes; advanced hot runner technology; AI process optimization.
- Advantages: Strong global support network; expertise in diverse industries; focus on digital manufacturing.
7. Wittmann Battenfeld (Austria)
Website: https://www.wittmann-group.com
A subsidiary of the Wittmann Group, Wittmann Battenfeld is an Austrian manufacturer of injection molding machinery and automation solutions, including specialized co-injection systems. Founded in 1899, the company is headquartered in Kottingbrunn, Austria, with production facilities in Europe, Asia, and the Americas. Wittmann Battenfeld’s co-injection technology is highly regarded for its integration with automation, enabling fully automated production of complex multi-material parts.
Wittmann Battenfeld’s co-injection machines are designed for high-precision applications, with a focus on the automotive, electronics, and medical industries. The company offers both two-component and multi-component co-injection solutions, with capabilities for processing materials including engineering plastics, TPE, and silicone. A key feature of Wittmann Battenfeld’s co-injection systems is their seamless integration with the company’s automation and robotic solutions, enabling parts handling, inspection, and assembly in a single production line.
In 2024, Wittmann Battenfeld launched its PowerSeries Co-Injection line, which combines high speed with energy efficiency, reducing cycle times by up to 15% while cutting power consumption by 28%. The company also provides comprehensive process consulting, helping clients optimize their co-injection processes for maximum quality and efficiency. With a strong focus on Industry 4.0, Wittmann Battenfeld enables full connectivity between its co-injection machines and production management systems, supporting smart manufacturing initiatives.
Co-Injection Capabilities and Advantages:
- Core Capabilities: Two and multi-component co-injection; high-precision electronic and medical parts; fully automated production lines.
- Technical Advantages: Seamless automation integration; fast cycle times; high energy efficiency.
- Advantages: Austrian engineering precision; fully automated production solutions; Industry 4.0 compatibility.
8. Ferromatik Milacron (Germany)
Website: https://www.ferromatik.com
Part of the Milacron group, Ferromatik Milacron is a German manufacturer of injection molding machinery, specializing in high-performance co-injection systems. Headquartered in Kottingbrunn, Austria, with a key production facility in Malterdingen, Germany, the company has over 100 years of experience in plastics processing. Ferromatik Milacron’s co-injection solutions are widely used in the automotive, medical, and electronics industries, known for their high precision and reliability.
Ferromatik Milacron’s co-injection machine line includes the K-Tec and Evolution series, which offer clamping forces from 80 tons to 4,500 tons, suitable for a range of part sizes. The company provides both sequential and simultaneous co-injection technologies, with specialized systems for multi-material over-molding and barrier layer production. A key strength is the company’s expertise in processing high-performance materials, including liquid silicone rubber (LSR) and engineering plastics, making its co-injection systems ideal for medical and automotive applications.
In recent years, Ferromatik Milacron has invested in sustainable co-injection solutions, developing processes that use recycled and bio-based materials without compromising part quality. The company’s co-injection systems also incorporate advanced energy-saving technology, reducing operational costs for clients. Ferromatik Milacron works with major global brands including BMW, Siemens, and Roche, and offers comprehensive service and support, including training and process optimization consulting.
Co-Injection Capabilities and Advantages:
- Core Capabilities: High-performance material co-injection; LSR processing; automotive and medical components.
- Technical Advantages: Precise material dosing; low-waste production; energy-efficient design.
- Advantages: German engineering expertise; specialized medical and automotive solutions; global client support.
9. Barnes Group Inc. (United States)
Website: https://www.barnesgroupinc.com
Founded in 1857, Barnes Group Inc. is a global industrial manufacturing and services company, with a plastics division that specializes in co-injection mold design and production. Headquartered in Bristol, Connecticut, United States, the company operates facilities in North America, Europe, and Asia, serving clients across automotive, aerospace, medical, and industrial sectors. Barnes Group is renowned for its custom co-injection mold solutions, enabling production of complex multi-material parts with high precision.
Barnes Group’s co-injection services include mold design, mold manufacturing, and production support, working closely with clients to develop tailored solutions for their specific part requirements. The company’s co-injection molds are designed for applications ranging from small medical connectors to large aerospace components, with expertise in multi-material combinations including plastic-over-plastic, plastic-over-rubber, and plastic-over-metal inserts. Barnes Group invests heavily in R&D, with a team of mold designers and process engineers who specialize in co-injection technology.
In 2025, Barnes Group launched its Advanced Co-Injection (ACI) program, which leverages simulation technology to optimize mold design and material flow, reducing part defects by up to 30% and shortening lead times. The company also focuses on sustainable manufacturing, designing co-injection molds that enable material usage reduction and integration of recycled plastics. Barnes Group works with major clients including Boeing, Ford, and Medtronic, and adheres to strict quality standards including AS9100 for aerospace and ISO 13485 for medical devices.
Co-Injection Capabilities and Advantages:
- Core Capabilities: Custom co-injection mold design; multi-material insert molding; aerospace and medical parts.
- Technical Advantages: Advanced simulation for mold optimization; expertise in complex insert molding; high-precision mold manufacturing.
- Advantages: End-to-end co-injection mold solutions; adherence to aerospace and medical standards; global production support.
10. Yizumi Group (China)
Website: https://www.yizumi.com
Founded in 2002, Yizumi Group is one of China’s leading manufacturers of injection molding machinery, including specialized co-injection systems. Headquartered in Foshan, Guangdong, with production facilities across China and sales offices in over 30 countries, Yizumi has grown to become a major global player in plastics processing technology. The company’s co-injection solutions are used in automotive, packaging, consumer electronics, and home appliance industries, renowned for their high cost-performance ratio.
Yizumi’s co-injection machine line includes both two-component and multi-component systems, with clamping forces from 100 tons to 4,000 tons, accommodating a wide range of part sizes. The company offers specialized co-injection technologies for applications such as automotive interior parts, home appliance components, and packaging containers, with expertise in processing materials including PP, ABS, TPE, and engineering plastics. Yizumi’s co-injection systems are designed to be user-friendly, with intuitive control interfaces and reliable performance suitable for high-volume production.
In recent years, Yizumi has invested heavily in R&D, establishing a global R&D center in Germany and partnering with leading material suppliers to develop innovative co-injection solutions. The company’s co-injection systems incorporate advanced energy-saving technology, reducing power consumption by up to 30% compared to traditional models. Yizumi also provides comprehensive after-sales service, including installation, training, and maintenance support, serving clients across Asia, Europe, and the Americas. Major clients include Haier, Midea, and Geely Automobile, solidifying Yizumi’s position as a leading co-injection factory in Asia.
Co-Injection Capabilities and Advantages:
- Core Capabilities: Two and multi-component co-injection; automotive and home appliance parts; packaging containers.
- Technical Advantages: Energy-efficient design; user-friendly control systems; reliable high-volume production.
- Advantages: Cost-effective solutions; strong Asia-Pacific market presence; comprehensive after-sales support.
Conclusion
The global co-injection manufacturing industry in 2026 is defined by a diverse group of leading factories that bring together technical innovation, quality expertise, and sustainability focus to meet evolving market demands. The top 10 factories listed here—including Hengji Mould & Plastic Co., Ltd., Husky Technologies, Sumitomo (SHI) Demag, and others—represent the pinnacle of co-injection technology, serving key industries from automotive and medical to packaging and electronics. Each factory brings unique strengths: from Hengji’s specialized automotive co-injection and sustainable material integration to Husky’s packaging-focused multi-layer technology, and from German engineering precision to Japanese reliability and Chinese cost-effectiveness.
As global demand for lightweight, durable, and multi-functional products continues to rise, these leading co-injection factories are investing in advanced technologies such as AI process optimization, Industry 4.0 connectivity, and recycled/bio-based material integration to drive sustainable growth. Their ability to deliver high-quality, complex multi-material parts at scale positions them as critical partners for global OEMs across sectors, while their ongoing innovation ensures they will remain at the forefront of the co-injection market in the years to come. Whether serving the automotive industry’s shift to electric vehicles requiring lightweight structural parts, or the packaging sector’s need for sustainable barrier materials, these top 10 co-injection factories are shaping the future of manufacturing through their expertise and commitment to excellence.
