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Hangzhou Rainbow Import & Export Co., Ltd.

Professional PVP Polymer Manufacturer and Global Supplier Since 1992

Serving as the international export arm of Sunflower Group, Hangzhou Rainbow Import & Export Co., Ltd. delivers a full portfolio of polyvinylpyrrolidone (PVP), PVP/VA copolymers, crospovidone (PVPP), povidone iodine, and related specialty polymers, trusted by pharmaceutical, cosmetic, personal care, and industrial manufacturers worldwide.

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Hangzhou Rainbow Import & Export Co., Ltd.

 

 

 

 

 

35+

Years Experience

Since 1992, focused on the development and manufacturing of PVP-based specialty polymers.

1,700+ T

Annual Capacity

Stable production capability covering PVP, PVP/VA, PVPP and Povidone Iodine products.

50+

Global Markets

Long-term supply experience across pharmaceutical, cosmetic and industrial markets worldwide.

USP · EP · ChP

International Quality

Products manufactured and tested in accordance with internationally recognized pharmacopoeial requirements.


Our Manufacturing Journey in Povidone Production

Our roots trace back to 1992, with the establishment of Zhejiang Sunflower New Material Co., Ltd., one of China's pioneering companies dedicated to the research, development, and production of PVP polymers.

Over more than 30 years of continuous innovation, we have developed deep expertise in polymer chemistry, process engineering, quality control, and application technology.

Today, our products are delivered to customers across Asia, Europe, North America, South America, the Middle East, and Africa, supporting formulation development and manufacturing needs in highly regulated, performance-driven industries.

Our Manufacturing Heritage

 

 

Our History

BUILDING EXPERTISE IN PVP TECHNOLOGY SINCE 1992

Our Foundation and Technological Origins (1992)

Our journey began in 1992 under the leadership of Professor Wu Jiaxiang, a pioneering expert in China's PVP industry and former chief expert of the national PVP research program. From the outset, we focused on advancing PVP technology, establishing robust research and development capabilities that laid the groundwork for future growth.

Early Expansion (1992–2002)

Starting with the production of Povidone products, we steadily expanded both our manufacturing capacity and product portfolio. Continuous development of application technologies enabled us to meet evolving demands across pharmaceutical, cosmetic, and industrial sectors.

Global Development and Innovation

Over the following decades, technical expertise, process optimization, and strategic market development transformed the company into a globally recognized manufacturer. Our growth has been underpinned by ongoing investment in advanced manufacturing infrastructure, rigorous quality systems, and customer-focused innovation, allowing us to serve clients worldwide with reliable, high-performance PVP-based products.

Our Manufacturing Capabilities

Advanced Polymer Production Facilities designed specifically for the production of pyrrolidone-based polymers and related specialty materials.

 

Integrated Manufacturing System

  • Polymerization technology
  • Purification systems
  • Drying technology
  • Milling and particle control
  • Blending systems
  • Packaging operations
  • Quality control laboratories

This integrated setup allows us to maintain strict process control, ensuring consistent batch-to-batch quality, stable product performance, and reliable supply for long-term customer requirements.

Annual Production Capacity

Low Molecular Weight Povidone Series
PVP K12, K15, K17, K25, K30
600 Tons
High Molecular Weight Povidone Series
PVP K60, K90, K120
800 Tons
Povidone Iodine
Antimicrobial specialty formulations
300 Tons
Chondroitin Sulfate Sodium
Specialty polymer supplement grade
100 Tons

Factory & Production Facilities View

Polymerization Unit

FACTORY & PRODUCTION FACILITIES VIEW

Purification System

FACTORY & PRODUCTION FACILITIES VIEW

Drying & Milling

FACTORY & PRODUCTION FACILITIES VIEW

Packaging & QC

FACTORY & PRODUCTION FACILITIES VIEW

Our manufacturing capacity is designed to ensure stable long-term supply while accommodating customized customer requirements.

Comprehensive Product Portfolio

Povidone (PVP) K Series

A water-soluble synthetic polymer widely used across multiple industries due to its excellent versatility and functional performance.

Grades: K12 / K15 / K17 / K25 / K30 / K60 / K90 / K120

Key Functions: Binder, Solubilizer, Film former, Dispersing agent, Stabilizer, Thickener.

PVP/VA Copolymer Series

A copolymer system designed to provide an optimal balance between film strength and flexibility, ensuring stable performance in formulation systems.

Applications: Hair styling, sprays, gels, cosmetics, pharmaceuticals

Benefits: Film formation, humidity resistance, improved flexibility, reduced brittleness.

Crospovidone (PVPP)

A crosslinked, insoluble PVP-based polymer used as a superdisintegrant and functional adsorbent in multiple industries.

Applications: Tablets, nutraceuticals, beverage clarification, herbal purification

Advantages: Rapid swelling, excellent adsorption, high stability, superior dispersibility.

Povidone Iodine

A stable complex of PVP and iodine that combines carrier functionality with broad-spectrum antimicrobial activity.

Applications: Pharmaceutical preparations, antiseptic formulations, disinfectants

Scope: Widely trusted across healthcare, medical operations, and veterinary products.

Quality Assurance System

Quality Built Into Every Production Stage

Ensuring consistent product quality and reliability is at the core of our manufacturing philosophy. We implement a comprehensive quality management system across every stage of production, from raw material sourcing to final product release.

1. Raw Material Qualification

All incoming materials are rigorously evaluated and approved through established supplier management protocols and inspection procedures to guarantee consistent quality from the start.

2. Process Control

Critical production parameters are continuously monitored and controlled throughout the manufacturing process to ensure reproducibility, stability, and batch-to-batch consistency.

3. Finished Product Testing

Each batch is thoroughly tested for identity, composition, assay, moisture, viscosity, particle size, microbiology, and stability to ensure consistent quality, reliable performance, and regulatory compliance.

International Standards Compliance

Our products are manufactured and tested in accordance with internationally recognized pharmacopoeial standards, including USP, EP, and ChP. Quality management systems are fully aligned with ISO 9001 requirements, ensuring regulatory compliance, continuous improvement, and customer confidence.

Quality Assurance System

 

Research & Development

Innovation Driven by Application Expertise

Research and development remain at the core of our long-term growth strategy. Our technical team possesses extensive experience in:

  • Polymer chemistry
  • Formulation science
  • Pharmaceutical excipients
  • Cosmetic ingredients
  • Industrial application development

Continuous investment in technology development enables us to support evolving customer requirements and emerging market opportunities.

Industries We Serve

Pharmaceutical Industry
Tablet binders, film coating systems, solubilizers, suspension stabilizers, disintegrants.
Cosmetics and Personal Care
Hair styling products, skin care products, color cosmetics, sunscreen formulations.
Industrial Applications
Pigment dispersants, adhesives, coatings, detergents, membrane technology, ink formulations.
Healthcare and Disinfection
Antiseptic products, medical disinfectants, veterinary formulations.

Why Global Customers Choose Rainbow

35+ Years of Industry Expertise

Long-standing specialization in PVP polymer technology and large-scale manufacturing since 1992.

Comprehensive Product Portfolio

A full range of PVP, PVP/VA, PVPP, and Povidone Iodine solutions for pharmaceutical, cosmetic, and industrial applications.

Stable Production Capacity

Reliable and scalable manufacturing capability supporting consistent long-term global supply.

Consistent Product Quality

Strict quality management systems combined with standardized testing to ensure batch-to-batch consistency.

Global Market Experience

Proven supply record across multiple international markets and regulatory environments.

Professional Technical Support

Application guidance, product selection, and formulation support tailored to customer requirements.

 

Our Mission

To deliver high-quality polymer solutions that enhance product performance, improve manufacturing efficiency, and strengthen customer competitiveness through continuous innovation, consistent quality, and professional service.

 

Our Vision

To become a globally trusted supplier of specialty polymer technologies and a long-term strategic partner to customers across pharmaceutical, cosmetic, and industrial markets worldwide.

 

 

Ready to partner with a reliable global PVP polymer manufacturer?

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