What Is the Differences Between Silicone Oil, Softener Flakes and Fatty Amide Softener?

The Introduction of Finishing Softeners for Textiles

Softening Finishing is a very crucial post-finishing processing of fabrics and denim garment washing, it directly determines the hand feel of the fabrics and Jeans, but sometimes also can influence the moisture absorbency, tendency to yellowing and sewability properties.

Whether the fabric manufacturing plants, denim washing plants, or auxiliary formulators may face the difficulty in choosing a proper softening finishing agents.

On the market, there are mainly three kinds of softening finishing agents: silicone oil, softener flakes, and liquid fatty amide softener, a certain number of technical people easily confuse the chemical properties, hand feel styles, and application scenes of these three softening finishing agents.

It is also very necessary for formulators to differentiate the silicone oil ( base oil as raw material) and the finished emulsion softener. And the end users need choose the proper products considering the fabrics and processing skills together, the proper selection of the right softeners can effectively reduce the product defect rates and control overall production costs.

On this blog, we will give a detailed description about these three main different softening finishing agents as under.

Silicone Oil: Distinguishing Between Base Oil and Finished Emulsion

The “silicone oil” generally refers to the silicone base fluids, such as amino-modified silicone oil and hydrophilic-modified silicone oil, which is the base oil to produce the finished emulsion softener. These raw material silicone oils cannot be applied directly to fabrics. Amino-modified silicone oil is the most widely-used type, imparting a remarkably silky hand-feel to fabrics, while hydrophilic-modified silicone oil offers softness without compromising the fabric’s absorbency.

Formulators process these fluid base silicone oils by adding emulsifiers and water to create a finished milky-white emulsion, which is designed for direct use by dyeing and garment-washing facilities, is known in the industry as a silicone softener.

However, in the daily oral communications in many fabric mills, the term “silicone oil” is also often used to refer to the finished silicone softener emulsion. Since both terms are used interchangeably in the industry, it is essential to clarify with the customer whether they require the raw fluid silicone base oil or the finished silicone softeners.

It is also very necessary to note that improper handling of silicone softener emulsions can easily lead to silicone spots to the fabrics. Such defects are difficult to rectify, making this one of the most common pain points in production.

Softener Flakes and Fatty Amide Softener: Same Chemical Components, in Different Physical Appearances

Some people don’t know that both softener flakes and liquid softening oil (softening oil concentrate) are in the same chemical composition: cationic fatty acid amides, differing only in their physical forms.

Under high-temperature, it is a brown liquid (known in the industry as “softening oil”), once it is cooled, solidified, and sliced, it becomes solid “softener flakes.”

Liquid softening oil can be diluted directly with water at room temperature for processing, which is very easy for use and requires no heating for dissolution. Softener flakes, being high-solid products, having a lower storage and transportation costs but must be fully dissolved at high temperatures during use. Incomplete melting can easily lead to the formation of particles or oil spots on the used fabric surface, resulting in batches of defective goods.

Paraffin-based softener flakes are also available on the market, these have a completely different chemical composition, so it is important to distinguish them during procurement and selection sections, they can not be conflated.

Differences on Fabric Hand Feel for Three Softeners

The fabrics finished by the finished softener emulsion ( the raw material is base silicone oil ), the hand feel of the finished fabrics is characterized primarily by a silky, oily-smooth hand-feel, which isn’t matchable by other softener flakes, and liquid fatty amide softeners. It is ideal for high-end fabrics and denim garments. Certain modified silicone oils can also enhance fabric resilience, making them suitable for mid-to-high-end fabric orders.

Fatty acid amide-based softeners (softener flakes, and liquid fatty amide softeners) impart a voluminous, plump, and soft, cotton-like feel, but offer less smoothness. This type of hand-feel is well suitable for knitwear, towels, and standard woven fabrics, offering excellent cost-effectiveness, it’s ideal for large-volume, standard orders. Unlike silicone oils, these fatty acid amide-based softeners don’t have an intense oily-smooth sensation, favoring a more natural, unadorned texture instead.

There is no absolute standard for a “good” hand-feel, it depends entirely on the client’s specific requirements. Some formulators blend different softeners together to combine the benefits of bulkiness and smoothness, thereby developing customized solutions for specific hand-feel requirements.

Comparison of Production Defects Commonly found Across Different Softener Types

The most typical issues with silicone oil-based softeners are silicone spotting and fabric staining issues caused by emulsion breakdown, and the amino-silicone products carry a risk of yellowing, as well the traditional silicone oils tend to reduce fabric absorbency. A major challenge is that rectifying silicone spots involves a complex rework process, significantly increasing factory losses.

The primary risk of softener flakes comes from the dissolution process, insufficient dissolution temperatures or inadequate agitation can leave the solid particles in the treatment bath, resulting in oily spots on the fabric surface. Both liquid fatty amide softener and softener flakes are cationic products and cannot be used in the same bath along with the anionic auxiliaries, avoid causing precipitation and loss of effectiveness.

All these three types of softeners can cause yellowing problem at different certains. If the mills want to use these softeners on light-colored fabrics, it is suggested that lab-scale testing should be prioritized to assess yellowing characteristics before proceeding them to bulk production.

How to Select Raw Material Softener for Formulators

For formulators, shall firstly clearly distinguish the raw materials and finished softeners. When sourcing silicone-based oils to formulate the finished emulsion softener, shall focus on the amine value and viscosity stability of the base oil, then formulate the raw material silicone oil to the finished emulsion softener by the emulsification system according to the requirement of fabric hand feel.

Regarding fatty acid amide raw materials, formulators can choose liquid softeners and solid softeners flakes depending on their needs. Solid softeners flakes offer a higher concentration of active ingredients, which helps optimize formulation costs, whereas liquid softeners eliminate the melting step and simplify the production process. Silicone-based and fatty acid-based raw materials can also be blended to develop differentiated products.

During procurement, low-priced paraffin-based softening flakes can be ignored or must be selected carefully unless the formulators only care about the low price, although their price is low, they tend to impart a waxy feel and have limited performance, and cannot be directly competeable to fatty acid amide softening flakes.

How Fabric Mills and Garment Washing Plants Should Select Ready-to-Use Softeners?

When selecting ready-to-use softeners, end users shall be prior to consider the fabric types and specific requirements. For cotton knits, towels, and standard woven fabrics where a fluffy, soft, and supple hand-feel is desired, softening oils or fully dissolved softener flakes are the preferred choice. For high-end denim and fashion fabrics requiring a silky touch, the silicone softener emulsions are selected.

For light-colored fabrics, yellowing resistance must be a key evaluation criterion. For towels and home textiles, absorbency-maintainment is essential, so hydrophilic-modified products are prioritized. Before proceeding to full-scale production with any new softeners, lab tests and plant trials must be proceeded to verify that hand-feel, shade, and absorbency all meet specifications.

Additionally, chemical compatibility must be considered too, cationic softeners must not be added to the same bath with anionic softeners and other anionic auxiliaries.

Conclusion

Whether choose which type of softeners, processing conditions directly impact the final outcome.
Softener dosages differ significantly between padding and exhaustion processes, must be adjusted based on factors such as liquor ratio, processing speed, and fabric weight.

Temperature and pH levels also alter the performance of softeners. Softening flakes require sufficient temperatures for complete dissolution, while silicone oil emulsions must be protected against emulsion breakdown caused by extreme pH values.

Excessive dosage does not yield infinitely better hand-feel, instead it may lead to a range of negative issues, such as a tacky fabric surface, color shade shifts, and reduced absorbency.

Lab test is indispensible. Strictly controlling the chemical preparation process, and regularly maintaining the working bath can effectively minimize the most quality defects associated with softening finishes and ensure consistent hand-feel across production batches.