Cotton Linter - Grade Guide
Introduction
Cotton linter, a byproduct of cottonseed processing, has distinct market grades, each with unique characteristics. Understanding the specifics of 1st, 2nd, and 3rd cuts (common terminology for grade), alongside mill-run grades, is essential for parties involved in cotton linter supply & use. In this blog post we explore the most common linter grades available on the market and detail their fibre length, production processes, colouration, trash content, and applications.
What are Cotton Linters?
Before exploring specific cuts (grades), let’s go over the fundamental concept of cotton linter. Linters are short fibres that adhere to cottonseeds after the ginning process. After ginning, cotton linters undergo additional processing steps to refine and purify, leaving fibres that are rich in cellulose, ready to be the foundation for a wide range of products across industries.
Linters are often referred to as “cuts” rather than “grades” because the terminology reflects the specific cutting or separation of the fibers during the ginning process, where the length of the fibers is determined. The terms “1st cut,” “2nd cut,” and so on, denote the sequential separation of fibers during ginning cycles based on their length, providing a more practical and descriptive classification for these distinct segments of cotton linters.
1st Cut Cotton Linter
The highest grade of cotton linter on the market is 1st cut cotton linter. This grade is obtained during the first ginning where mechanical processes strip the fibres from the seeds.
1st cut cotton linter features the longest fibres, typically exceeding 1/2 inch [12.7 mm]. These fibres are characterized by their superior quality, purity and cellulose yield and are highly valued in industries requiring premium raw materials. Their length makes them suitable for applications such as high-quality paper production, speciality chemicals, and specific medical uses.
Additionally, 1st cut cotton linters are often characterized by their white colouration, making them suitable for applications requiring high purity. They generally have low trash content.
2nd Cut Cotton Linter
The next grade of cotton linters is 2nd cut cotton linters. This grade is produced from subsequent ginning cycles after the initial extraction.This process ensures the separation of fibres of varying lengths, with fibre lengths ranging between 1/4 to 1/2 inch [6.35 to 12.7 mm].
2nd-cut cotton Cotton linters, while not as lengthy as 1-cut fibres, still offer valuable characteristics, including high cellulose yield. Their versatility makes them suitable for various applications, including paper manufacturing, absorbent materials, and certain chemical products.
2nd cut cotton linters may exhibit colour variations, often leaning towards off-white or light cream. Their trash content is moderate.
3rd Cut Cotton Linter
Continuing the ginning process yields 3rd cut cotton linters, which are a cost-effective option for industries with less stringent length requirements.
3rd cut cotton linters have shorter fibres compared to both 1st and 2nd cuts, generally shorter than 1/4 inch [6.35 mm], lower cellulose yields and are considered a lower-quality grade, with a range of colouration present, and higher trash content
Mill-run Cotton Linter
Mill-run cotton linters is a mixed-grade cotton linter produced by combing the fibres from multiple ginning cycles. Typically made up of 1st cut and 2nd cut cotton linters, mill-run linters have a range of lengths, cellulose yield, colouration and trash content that is specific to each grade.
Mill-run cotton linters are produced using a distinct type of machine, where fibres from various ginning cycles are combined without specific segregation based on length. This grade of linter is more common in South Asia, Africa, and South America, where this different ginning process takes place.
Despite the mixed nature, mill-run cotton linters are favoured for their cost-effectiveness and versatility in various industries. Their diverse mix of fibre lengths makes them an attractive option for applications where variations are acceptable. Industries seeking a balance between quality and cost often opt for mill-run linters, utilizing them in the pulp and paper industry for specific paper grades or in non-textile sectors such as chemicals and pharmaceuticals.
The ability to repurpose the entire cotton crop aligns with sustainability goals, minimizing waste and providing a valuable raw material for numerous manufacturing processes. Overall, the use of mill-run cotton linters is driven by the specific requirements and considerations of industries aiming to optimize both efficiency and resource utilization.
Cotton at TP-Exports
At TP-Exports, we deliver cotton to industries globally, including 1st, 2nd and mill-run cotton linters.
With a developed Agri division built on sustainability and transparency, our industry-focused approach ensures every bale we deliver carriers the assurance of traceability and risk mitigation. We utilise per-bale HVI testing and farm origin tracking, to bring resilience to your supply chain and deliver better raw material solutions.
Explore our site to understand further our cotton capabilities and what we can deliver for your requirements. For a quotation or to speak with someone, please refer to our Contact Us page.