Anionic vs. Non-Ionic Waterborne Latent Curing Agents: What Is the Difference in Water-Based Sealed Curing Agents?
Release time: 2026-09-10
Table of Contents
HeFei Conada New Materials Co.,Ltd. focuses on the research, development, and promotion of new material technologies, including water-based materials, coatings, inks, and other synthetic materials. Among its waterborne curing products, CR-40S and CR-2820 are two latent curing agents with different ionic properties. Comparing them is useful when selecting a water-based sealed curing agent for a specific formulation or application.
What Is a Waterborne Latent Curing Agent?
A waterborne latent curing agent can remain stable with resins containing active groups such as hydroxyl, carboxyl, amino, and epoxy groups at room temperature.
For CR-40S and CR-2820, the curing process takes place after heat treatment at 110–120 °C. During heating, -NCO groups are released and react with active groups in the resin to form crosslinks. This can improve properties such as color stability, adhesion, bonding fastness, and cooking resistance in polyurethane, polyester, alkyd, and acrylic resin systems.
The two products have similar basic technical parameters, but their ionic properties and some product features are different.
CR-40S and CR-2820: Key Differences
| Item | CR-40S | CR-2820 |
| Product type | Non-ionic waterborne latent curing agent | Anionic waterborne latent curing agent |
| Ionicity | Non-ionic | Anionic |
| Appearance | Milky white liquid with blue tint | Milky white liquid with blue tint |
| Solid content | 40±2% | 40±2% |
| Viscosity | ＜100 mPa·s | ＜100 mPa·s |
| Density | 1.15–1.25 g/cm³ | 1.15–1.25 g/cm³ |
| NCO content after deblocking | 4.5–5.0% | 4.5–5.0% |
| Deblocking temperature | 110–120 °C | 110–120 °C |
| Main stated features | Soft hand feel, water-dilutable, VOC-free, good yellowing resistance | Good hydrolysis resistance after curing, good yellowing resistance |
The main difference is therefore the ionic type: CR-40S is non-ionic, while CR-2820 is anionic. Their other listed technical parameters are the same.
What Makes CR-40S Different?
CR-40S is a non-Ionic waterborne latent curing agent designed for waterborne resin systems. Its product features include a soft feel after curing, water dilutability, and no VOCs. It also has a low deblocking temperature of 110–120 °C and good yellowing resistance.
After heat treatment, the released -NCO groups react with active groups in the resin and form crosslinks. According to the product data, this can improve color stability, adhesion, bonding fastness, and cooking resistance.
The soft hand feel is particularly relevant to applications where the feel of the finished material matters. CR-40S is also used in textile coatings and printing adhesives, three-proof emulsions, waterborne coatings, metal baking finishes, and polyester cord fabric treatment.
What Makes CR-2820 Different?
CR-2820 is an anionic waterborne latent curing agent. Like CR-40S, it can remain stable with resins containing active groups at room temperature and releases -NCO groups after heat treatment at 110–120 °C.
Its stated product features include good hydrolysis resistance after curing, a low deblocking temperature, and good yellowing resistance.
CR-2820 can be used in the same five application areas listed for CR-40S, including waterborne coatings, three-proof emulsions, textile coatings and printing adhesives, metal baking finishes, and polyester or polyester cord fabric treatment.
Which Properties Should You Compare?
When comparing two waterborne latent curing agents, it is useful to look at several basic properties rather than focusing only on ionic type.
Ionicity
CR-40S is non-ionic, while CR-2820 is anionic. This is the clearest difference between the two products and should be considered together with the requirements of the formulation.
Deblocking Temperature
Both products have a deblocking temperature of 110–120 °C. After heat treatment within this range, -NCO groups are released and can react with active groups in the resin.
For applications involving heat-curable waterborne systems, this parameter should be considered alongside the actual curing process.
Yellowing Resistance
Both CR-40S and CR-2820 are described as having excellent yellowing resistance. This makes yellowing resistance one of the common properties of the two products rather than a major point of difference.
Performance After Curing
The two products have different stated highlights in this area. CR-40S is noted for its soft hand feel after curing, while CR-2820 is noted for good hydrolysis resistance after curing.
These differences can be useful when comparing the requirements of a particular application.
Basic Physical Parameters
Both products have a solid content of 40±2%, viscosity below 100 mPa·s, and a density of 1.15–1.25 g/cm³. Their NCO content after deblocking is 4.5–5.0%.
The actual values should be checked against the product COA, since the listed laboratory results are typical results rather than specifications.
Where Can These Products Be Used?
CR-40S and CR-2820 are listed for several waterborne coating, textile, and bonding applications.
1. One-component heat-curable waterborne coatings
Both products can be used as internal crosslinkers to improve water resistance, chemical resistance, abrasion resistance, adhesion, and the mechanical properties of waterborne resin films.
2. Three-proof emulsions
They can be used as additives for fixing organic fluorine or silicone on cotton or polyester fibers and increasing washing resistance.
3. Textile coatings and printing adhesives
Both products can serve as internal crosslinkers to improve adhesion, washing resistance, abrasion resistance, and color stability.
4. One-component metal baking finishes
They can be used as internal crosslinkers in one-component metal baking finishes. According to the product information, they can replace amino resins to reduce brittleness and offer a formaldehyde-free option with good yellowing resistance.
5. Polyester and polyester cord fabric treatment
Both products can be used as treatment agents for polyester or polyester cord fabric to improve adhesion between polyester and rubber.
How Should You Choose Between CR-40S and CR-2820?
There is no need to treat one product as a general replacement for the other. The choice can start with the differences stated in their product data.
CR-40S may be considered when a non-ionic product is required, especially when soft hand feel, water dilutability, and VOC-free characteristics are important considerations.
CR-2820 may be considered when an anionic product is required or when good hydrolysis resistance after curing is an important consideration.
For either product, the final choice should also take into account the resin type, curing conditions, application, and required film or fabric properties. Testing the product in the actual formulation is recommended before full-scale use.
Frequently Asked Questions
1. What is the main difference between CR-40S and CR-2820?
The main difference is ionicity. CR-40S is non-ionic, while CR-2820 is anionic. They have the same listed solid content, viscosity, density, NCO content after deblocking, and deblocking temperature.
2. Do both products require heat treatment?
Yes. Both products are designed to undergo heat treatment at 110–120 °C. After heating, released -NCO groups react with active groups in the resin to form crosslinks.
3. Are CR-40S and CR-2820 suitable for waterborne coatings?
Yes. Both are listed as internal crosslinkers for one-component heat-curable waterborne coatings. They are also listed for textile coatings, printing adhesives, metal baking finishes, three-proof emulsions, and polyester cord fabric treatment.
4. Which product has better yellowing resistance?
Both CR-40S and CR-2820 are described in the product information as having excellent yellowing resistance, so this is not presented as a primary difference between them.
5. Which product provides a soft hand feel?
CR-40S is specifically described as having a soft feel after curing. This feature is not listed as a specific product feature for CR-2820.
6. Which product has hydrolysis resistance after curing?
CR-2820 is specifically described as having good hydrolysis resistance after curing.
7. How should the products be stored?
CR-40S should be stored in its original sealed container at 6–28 °C and protected from direct sunlight and contamination. Its shelf life is within 12 months from production.
CR-2820 should be stored in its original sealed container at 5–30 °C, also protected from direct sunlight and contamination. Its shelf life is 12 months.
Conclusion
CR-40S and CR-2820 are both waterborne latent curing agents with a deblocking temperature of 110–120 °C and similar listed technical parameters. The key difference is their ionic type: CR-40S is non-ionic, while CR-2820 is anionic.
The product features also differ in emphasis. CR-40S offers a soft hand feel, water dilutability, and VOC-free characteristics, while CR-2820 is noted for good hydrolysis resistance after curing. Both provide good yellowing resistance and can be used across the application areas listed in their product information.
HeFei Conada New Materials Co.,Ltd. provides technical support throughout product development and application, with a focus on water-based and other environmentally friendly material technologies. For specific formulations, its technical team can provide support based on the customer’s application requirements and testing needs.
