Sodium Silicate Vs Darvan 7: Which Is Right For You?

Darvan is a liquid alternative to sodium silicate, which is a commonly used material. It’s often used in ceramics and other applications.

For porcelain, you typically use about 0.35 parts of Darvan per 100 parts of clay powder. For stoneware that contains iron oxide, you might need up to double that amount.

Darvan offers several advantages over sodium silicate, making it a popular choice. It’s easier to use and can help to prevent the clay from clumping together.

Here’s a little more about Darvan and how it compares to sodium silicate:

Darvan is a trade name for a group of polymeric dispersants. They’re essentially long chains of molecules that help to keep particles suspended in a liquid. When added to a clay slurry, the Darvan molecules attach to the surface of the clay particles, creating a barrier that prevents them from sticking together.

Sodium silicate, on the other hand, is a simple compound that can act as a binder or a deflocculant depending on the concentration. At low concentrations, sodium silicate acts as a binder, helping to hold the clay particles together. At higher concentrations, it acts as a deflocculant, helping to keep the particles suspended.

So, are Darvan and sodium silicate the same? No, they are different materials with different properties. However, they can both be used to disperse clay particles, making them a valuable tool for ceramic artists and manufacturers.

Here’s a table that summarizes the key differences between Darvan and sodium silicate:

| Feature | Darvan | Sodium Silicate |
|—————-|——————————|—————————–|
| Type | Polymeric dispersant | Simple compound |
| Mechanism | Surrounds particles, creating a barrier | Can bind or disperse particles depending on concentration |
| Ease of Use | Easier to use | Can be tricky to use correctly |
| Effectiveness | Highly effective | Effectiveness can vary |

If you’re looking for a reliable and easy-to-use deflocculant for your ceramic projects, Darvan is a great option. It’s a powerful tool that can help you achieve consistent and high-quality results.

Darvan 7 is a great choice for making casting slips from whiteware and refractory compositions. It allows you to create slips with a wide range of casting properties. The slips you make are also pretty stable, they won’t thicken up too much when you leave them sitting around, and they don’t get too thick and gooey either. When you use these slips to make your ware, you’ll find the material is very workable and easy to shape.

Let’s dive a bit deeper into what makes Darvan 7 so special. It’s a deflocculant, which basically means it helps to keep the particles in your slip from clumping together. This is important because if the particles clump, your slip will be thick and hard to pour. Darvan 7 does a great job of preventing this clumping, giving you a smooth, easy-to-pour slip. Think of it like this: if you’re trying to make a smooth milkshake, you wouldn’t want all the ice cream and milk to clump together, right? You want it to be nice and blended! Darvan 7 does the same thing for your casting slip, ensuring it’s smooth and easy to work with.

Let’s break down the difference between Darvan 7 and Darvan 811.

Darvan 7 is a go-to for sodium silicate based clay bodies. It’s a great adjuster and you can use it without worrying about over-deflocculating your clay. This means you can use it to make your clay more fluid without making it too runny.

Darvan 811 is a different story. It’s a powerful deflocculant used for red and highly plastic clay bodies, such as Terra Cotta and stoneware. Deflocculants help break down the particles in clay, making it more fluid and easier to work with. When using Darvan 811, you won’t need to add soda ash or sodium silicate.

Darvan 811 is often chosen for red clays because it helps to evenly disperse the color pigments, leading to a more consistent and vibrant finish. Red clay tends to be more difficult to work with due to its high plasticity. Darvan 811 can help reduce the stickiness and make it easier to mold.

Think of Darvan 7 as a gentle nudge, perfect for everyday clay bodies, while Darvan 811 is a powerful tool that can really transform the properties of those challenging, highly plastic clays.

You’re right to wonder if Darvan 7 goes bad! It’s a great product, but like most things, it does have a shelf life. You’ll get the best results if you use it within two years of purchase.

But don’t worry, even if it’s been sitting on your shelf for a while, it doesn’t suddenly become dangerous or unusable. It just might not perform as well as it did when it was brand new.

Think of it this way: Darvan 7 is like a fine wine. It gets better with age, but only for a while. After a certain point, it starts to lose its flavor (or in Darvan’s case, its effectiveness).

Here’s what you can do to make sure you’re getting the most out of your Darvan 7:

Check the expiration date: Every container of Darvan 7 should have an expiration date printed on it. This is the date after which the product is no longer guaranteed to meet its performance standards.
Store it properly: Keep Darvan 7 in a cool, dry place, away from direct sunlight. This will help to prolong its shelf life.
Use it within two years: If you’re not planning to use Darvan 7 within two years, it’s best to purchase a smaller quantity or use it sparingly to avoid waste.

Remember, it’s always better to be safe than sorry. If you’re unsure about the quality of your Darvan 7, it’s always a good idea to contact the manufacturer for guidance. They can help you determine if it’s still safe to use and how to get the most out of your product.

You’re probably wondering how much Darvan 7-N to use for your grinding needs. Well, the good news is that it’s a versatile product that works well in a range of applications.

For dry grinding, 0.005% to 0.1% has proven effective in many cases. This means that for every 1000 grams of your material, you’d use between 0.05 grams and 1 gram of Darvan 7-N. Of course, the ideal amount will depend on your specific application and the properties of your material.

Darvan 7-N can also double as a binder, making it a truly multi-functional additive. In this role, you’d typically use about 2%. This means for every 100 grams of your material, you’d use 2 grams of Darvan 7-N.

Here’s a breakdown of what’s going on:

Darvan 7-N helps in dry grinding by reducing friction between particles. This leads to more efficient grinding and a finer, more consistent product. Think of it as a lubricant for your grinding process.
Darvan 7-N acts as a binder by creating a strong, cohesive bond between particles. This is particularly helpful if you need to create a stable, durable product, like a tablet or a pellet.

Remember: Experimentation is key! Always start with a small amount of Darvan 7-N and gradually increase it until you achieve the desired results. Be sure to carefully monitor the impact on your grinding process and the final product.

Here are some tips to keep in mind:

Particle size: The smaller the particles, the less Darvan 7-N you’ll likely need.
Material type: Some materials are more sensitive to additives than others. Start with a lower concentration and adjust accordingly.
Grinding method: Different grinding methods may require different amounts of Darvan 7-N.

Darvan 7-N can be a powerful tool for enhancing your grinding process. By understanding its properties and experimenting with different concentrations, you can achieve optimal results for your specific application.

Sodium silicate has a few other names you might come across. It’s also known as waterglass, water glass, or liquid glass. These names all refer to a mixture of sodium silicate compounds, primarily the metasilicate. Let’s dive a little deeper into why these alternative names are used.

Waterglass is the most common alternative name for sodium silicate. This name originates from the appearance of sodium silicate in its solid form. When sodium silicate is dissolved in water, it forms a thick, viscous solution that looks like glass. The name liquid glass comes from this same characteristic. It’s a bit of a misnomer, as it’s not actually liquid glass, but rather a solution of sodium silicate in water.

You might also see the term water glass used, which is simply a variation of waterglass. These names are interchangeable and all refer to the same substance.

It’s important to note that while sodium silicate is often called waterglass, it’s not a single compound. It’s actually a mixture of different sodium silicates, with the metasilicate being the most common. The composition of the mixture can vary depending on the manufacturing process and intended use.

Darvan 7-N is a great choice for plaster molds. It gives them a longer life than using sodium silicate and soda ash.

You want to make sure you read and understand the safety information before using Darvan 7-N, though. Always refer to the Safety Data Sheets, labels, and other product literature for the latest information.

Darvan 7-N is a deflocculant that helps to disperse the particles in a plaster mix, which makes the plaster more fluid and easier to work with. It also helps to create a stronger and more durable plaster.

Sodium silicate and soda ash are also deflocculants, but they don’t offer the same level of performance as Darvan 7-N. They can also cause the plaster to become brittle, which can lead to cracks and other damage.

Darvan 7-N is also less likely to cause the plaster to become discolored or stained. This is important because it helps to keep the plaster looking its best.

Why is a longer mold life important?

Mold life is how long a mold can be used before it starts to deteriorate. There are several factors that can affect mold life, including the type of plaster used, the care of the mold, and the frequency of use. But using Darvan 7-N can extend the life of your plaster mold. Here’s why:

Darvan 7-N creates a stronger and more durable plaster, which is less likely to crack or break.
Darvan 7-N prevents the plaster from becoming brittle, which can also lead to cracking and breakage.

Overall, Darvan 7-N is a great option for extending the life of your plaster molds. Just be sure to follow the safety instructions and you’ll be all set!

Darvan is a great liquid alternative to sodium silicate. It’s true that you might need to use a bit more of it – about twice as much (around 0.4-0.5%) – but it comes with some excellent advantages.

First of all, you usually won’t need to add soda ash as a complement. That’s a big plus because it simplifies the process. Another benefit is that Darvan won’t damage your plaster molds, which is really important for those working with delicate or expensive molds.

And let’s not forget about the slurries! They’re much less sensitive to over deflocculation and are more stable overall. This means you’ll have a smoother, more consistent experience when working with your materials.

So, is Darvan a good alternative to sodium silicate? In most cases, absolutely! It’s a great option for anyone looking for a reliable, user-friendly, and effective deflocculant.

Here’s a little more about Darvan and why it’s a great choice:

Darvan is a polymeric dispersant. This means it’s designed to help particles stay suspended in a liquid. It’s really good at breaking down the attraction between particles, which is exactly what you need to create a smooth, even slurry.

Sodium silicate, on the other hand, is a silicate, which is a compound made up of silicon and oxygen. While it can work as a deflocculant, it can be less effective and can also damage your molds.

Darvan is often used in ceramic slurries because it provides superior dispersion and stability. It’s also used in other applications, like paints, inks, and even pharmaceuticals.

* One key advantage of Darvan is that it’s much less sensitive to pH changes than sodium silicate. This means you’ll get a more consistent result, even if the pH of your slurry fluctuates a bit.

Overall, Darvan is a fantastic alternative to sodium silicate. It’s more versatile, more forgiving, and often produces better results. It’s well worth considering for your next project!

Darvan vs. Sodium Silicate: A Slurry Showdown

So, you’re looking to make a great ceramic slurry, but you’re not sure which deflocculant to choose: Darvan or sodium silicate? Let’s break down the differences, and you can decide which one is the right fit for you.

Darvan is a popular choice for a reason. It often eliminates the need for soda ash, which can be a real time-saver in your production process. Plus, Darvan is gentle on your plaster molds, preventing any unwanted damage. One of the best parts about Darvan is that its slurries are less prone to over-deflocculation. This means you’re less likely to have a super runny slurry that’s difficult to handle. It also makes the slurry more stable, meaning it’s less likely to separate over time. And let’s not forget about the added bonus of easier scrap reprocessing.

But sodium silicate also has its place. While it might require soda ash, it’s often a more economical option than Darvan. It’s also a good choice for specific applications where a lower viscosity is needed.

Let’s get into the specifics of why Darvan takes the lead in terms of slurry stability and easier reprocessing.

Slurry Stability:Darvan’s unique molecular structure allows it to create a more stable suspension. Imagine it as a tiny, invisible net that holds your ceramic particles in place, preventing them from settling out. This means your slurry will stay nice and evenly distributed, even over time. Sodium silicate, on the other hand, can sometimes lead to a slurry that’s prone to settling.

Reprocessing: Darvan slurries are easier to reprocess because of their stability. If you need to reuse your slurry after a casting, you’ll find that Darvan makes this process much smoother. Sodium silicate, due to its tendency to settle, can make it challenging to get a consistent slurry from reprocessed material.

In short:Darvan wins when it comes to slurry stability, ease of reprocessing, and gentleness on your plaster molds. While sodium silicate might be a good choice for certain applications, Darvan is often the preferred deflocculant for its overall ease of use and reliable results.

What is Darvan 7N?

Darvan 7N is a powerful deflocculant, a type of chemical additive used to improve the fluidity and stability of ceramic slips, which are mixtures of ceramic powders and water. By adjusting the slip’s viscosity, Darvan 7N allows for easier pouring and casting. This is particularly important when creating ceramic molds and castings.

Compared to using sodium silicate and soda ash, Darvan 7N offers a significant advantage: longer mold life. This means you can leave both drain and solid castware made from slips containing Darvan 7N in the molds for extended periods without compromising the quality of your finished product.

Here’s a deeper dive into why Darvan 7N makes such a difference in mold life:

Darvan 7N is a highly effective dispersing agent. This means it breaks down the clusters of ceramic particles in the slip, allowing them to move more freely and distribute evenly. This results in a smoother, more homogeneous slip that is easier to pour and cast.

Think of it like this: imagine a bowl of flour. The flour particles are clumped together, making it difficult to pour. If you add a dispersing agent, it will break down those clumps, making the flour smoother and easier to pour.

Darvan 7N also helps to prevent the slip from settling and separating over time. This is crucial for maintaining the consistency of the slip and ensuring that your casts are uniform.

This ability to stabilize the slip is what contributes to the extended mold life. Traditional methods using sodium silicate and soda ash can lead to sedimentation and hardening of the slip, which can damage the mold. Darvan 7N effectively eliminates these issues, allowing for longer-lasting molds and ultimately, more successful ceramic creations.

sodium silicate versus Darvan 7 – Ceramic Arts Daily Community

In comparison to the conventional soda ash-sodium silicate system, these polyelectrolytes produce slips with longer casting range, higher solids content, improved viscosity stability, fewer “soda” or “hard spots”, and significantly increased mold life. Ceramic Arts Daily Community

Darvan – Digitalfire

Darvan has advantages over sodium silicate. Typically soda ash is not needed as a complement and Darvan does not attack plaster molds. In addition, slurries are much Digitalfire

TECHNICAL DATA – Vanderbilt Minerals

Compared to the use of sodium silicate and soda ash, DARVAN 7-N enables longer life for plaster molds. Both drain and solid castware made from slips Vanderbilt Minerals, LLC

Understanding the Deflocculation Process in Slip

Darvan No. 7, Allied Colloids #311: These are examples of more modern sodium polyacrylate dispersants, and manufacturers compare them with sodium silicate making the following claims: Lower minimum viscosity Digitalfire

In the Studio: Mixing Casting Slip: Tips and Tricks

Sodium silicate is an extremely powerful deflocculant, which is why I dilute it with distilled water; there is more margin for error. While mixing (I use a paint mixer and a drill), slowly Ceramic Arts Network

VANDERBILT Minerals Technical Data

DARVAN 7-N gives plaster molds a longer life than does the use of sodium silicate and soda ash. Both drain and solid castware made from slips containing DARVAN ® 7-N Vanderbilt Minerals, LLC

PPP: Using Decorative Engobes – Ceramic Industry

The engobe must be the correct consistency for the intended method of application. It should be homogeneous, free of coarse particles and air bubbles, and Ceramic Industry Magazine

Techno File: Terra Sig Experiment

Darvan 7: High alkalinity ionic polymer. It is a deflocculant (similar to sodium silicate) that weakens the electrical attraction between clay particles, acting as a thinning agent in Ceramic Arts Network

DARVAN TechNicAl DATA 7-N DARVAN 7-N DARVAN 7-NS

DARVAN® 7-N and DARVAN 7-NS are sodium polymethacrylate dispersing agents. DARVAN 7-N or DARVAN 7-NS are effective dispersants for mineral pigments in water Vanderbilt Minerals, LLC