Cobalt Blue Frit

The four shades of cobalt blue frits produces, this ranks as the second lightest. cobalt blue frit is well suited for small blown work, as well as sculpture when a medium transparent blue is desired. Cobalt blue frits can take a lot of heat and can be worked in a wide range of flame settings. Stay out of reducing flames to prevent dulling or gray streaking to occur. Though the color is extremely intense, be sure to stay out of reducing flames to prevent any dulling or graying.

This article comes from northstarglass edit released

The Virtues of Vitreous Enamel

More than 500 years ago, the English chronicler Robert Fabyan described the science and art of vitreous (porcelain) enameling on metals, a practice that was already 15 centuries old. Today, vitreous enamel art is as vibrant as then. The industry of enameling metal panels, which blossomed in the 1800s and 1900s, had receded but is enjoying a resurgence thanks to new technological developments.

The Science of Vitreous Enamel: Boric Oxide Is Required

Vitreous enameling—the fusing of a thin layer of glass to a metal base—is virtually impossible to achieve on large areas unless the glass has a high (up to 25%) boric oxide content. From the day of its invention, enamel has been used to beautify metal objects, and once the technology had developed to allow its application to large pieces, its durability and protective power could be exploited.

Traditionally, an enamel surface is two coats, base and cover, each of which had to be applied and fired separately. But in the 1970s, the so-called 2C/1F process—two coats, one firing—was perfected. This technique decreases energy usage and process times dramatically. With advances in frit technology, the need for steel pre-treatment by pickling and nickel plating became unnecessary. As a result, effluent disposal costs and potential environmental risks are mitigated.

Enamel Glaze: Versatile and Beautiful

As a surface coating, especially iron and steel, vitreous enamel is unassailable. Highly durable with a long service life, it resists scratching and chemical marring. It is easy to clean, and therefore, very hygienic.

Microwave Mismatches

Microwave ovens are usually lined with plastic, stainless steel, or a painted surface. Okay for the basic process, but since integrated functions such as a grill, air circulation, and steam heating have been added, temperatures in the chamber can rise to 572°F (300°C) or more. Higher temperatures can result in staining, yellowing, and distortion. If an enamel lining is used, these faults are avoided altogether.

An added bonus is that because enameled steel has half the thermal conductivity of stainless steel, it actually improves food quality. This lower conductivity means less energy usage for the same cooking effect, shorter cooking times, and more vitamins retained in the cooked food.

This article comes from borax edit released

Function of Milling Additives for Enamel

Milling additives is very important part for porcelain enamel coating. There’re mainly four key materials to be used as milling additives for enamel coating. They are: Clay, Quartz, Sodium Nitrite and Borax. So what’s their function?

Nolifrit will give your answer:

1, Clay

The main function of clay is to make enamel slurry of suspension property, enhance the mechanical strength of dry powder body, at the same time expand the firing temperature range of enamel frit.

The usage amount of clay for daily enamel ground coat and cover coat is about 6-8 for every 100 enamel frit(weight ratio). Transparent frit about 5-6.5, industrial acid resistant ground coat will need about 10, industrial cover coat about 3-3.5, there is no clay needed for cast iron cover coat.

Impurities contains in clay will affect its quality. For example, organics will bring bubbles, pores and black dots defects on enamel surface. Iron oxide will make titanium white cover coat become yellowish so reduce its whiteness. For acid resistant blue enamel cover coat, Impurities contains in clay will make SiO2 and Al2O3 contents changed, then affect its acid resistance feature.

When Clay is over used, it will make enamel surface rough, reduce its glossy and acid resistance feature.

Hunan Noli Enamel Co., Ltd can supply high quality enamel clay. It’s all imported from one of the most professional clay manufacturer Müllenbach & Thewald GmbH, Germany. We are their agency of in China. Their MT-500/E,510/E,530/E series is especially designed forenamel coating, which has very good dispersibility and pausibility, which need less water in milling process.

2, Quartz

Only used in ground coat, using amount about 5-10. It will make enamel frit with higher fire-resistance and enhance chemical and thermal stability of enamel slurry.

We can produce 5,000 MT quartz powder every year, with very stable quality and competitive price.

3, Sodium Nitrite

Usually applied in ground coat, using amount is about 0.2-0.5(weight ratio). Main function is to prevent the rusty spot after enameling. It can also stop flow. But when over used, it will make firing temperature range of enamel frit become narrow, then boiling will happen when firing.

4, Borax

Mainly used in ground coat, using amount is about 0.5. It can prevent rust, decrease burned spot. Over using will cause boiling or burning when firing.

How to Prepare Ready to Use Enamel Powder

Ready-to-use enamel powder are basically mixed by several kinds of enamel frits and milling additives after ball milling. It mainly contains frits, clay, electrolytes, refractors and pigments. Ready-to use enamel powder can be divided into two types.


Complete Ready-to use enamel powder: The grinding process for this enamel powder is completely finished. It can be used just by stirring in a mixer.


1. Put sufficient amount of water into the mixing vessel. The mixer with a high shear force is recommended.


2. Add ready-to-use enamel powder gradually into the mixing vessel until the demanded enamel density is reached. Baume can be used instead of a vessel with fix volume, since it is easier to operate.

3. Stir or ball mill for 10 – 15 minutes. If submersion enamel is going to be used, mixing for overnight is recommended to achieve the enamel stability.


4. Sieved the prepared enamel slurry by a 80 mesh sieve and then it becomes ready to use.


Partial Ready-to-use enamel powder: The grinding process of this enamel powder is partially completed. This enamel powder should be grinded by the user in a mill up to the demanded fineness.


1,Put enamel powder into a mill.

2,Add sufficient amount of water into the mill.

3,Grind the enamel powder up to the demanded fineness.

4,Discharge the enamel slurry and after adjusting its suspension feature, the enamel powder is ready to use.

Features of Cadmium Red Pigment from Nolifrit

Cadmium red pigment is the compound of Cadmium Sulfide and Cadmium Selenide(3CdS•2CdSe). Usually, The ratio of Cadmium Sulfide is 55%, Cadmium Selenide 45%.

Chemical Name Cadmium red pigment
Chemical Compositions Cadmium Sulfide, Cadmium Selenide
Pigment Index No. Pigment red 108
CAS No. 12214-12-9
Shape Red powder
Crystal form Hexagonal crystalline, Cubic crystalline.
Temperature resistance(max) 900℃


Cadmium red pigment has very bright color. It’s of high temperature resistance, alkali resistance, light resistance, and atmospheric resistance. With strong coloring power and covering power, the color pattern of Cadmium red pigment can range from yellow, red to purple. The more Cadmium Sulfide(CdSe) contained in Cadmium red pigment, the darker its red color will be.

Cadmium red pigment can be applied in high temperature resistant paint. It also can be used in enamel, ceramic, glass, plastic, art pigment, print ink, paper, leather, colored sand architecture material and electric material, etc…

(Steel enamel cookware in Cadmium red color:)


(Le Creuset Cast iron enamel cookware in Cadmium red color:)


Hunan Noli Enamel Co., Ltd is the leader manufacturer of Cadmium red pigment in China, Focusing on the production of enamel pigments over 30 years.

As the sense of environmental protection enhanced in recent years, more and more small manufacturers of Cadmium red pigment have to stop their production, which makes Nolifrit the only and best choice for Cadmium red pigment. As our production is based on factories on west border areas in China, so there’s no worries for environmental pollution.

Cadmium red pigment produced in Nolifrit is very cost-effective, the price is half of the current international brand. Much cheaper than Ferro and Pemco(Prince).

Nolifrit once had a meet with the world’s top one brand of colored cast iron enamel cookware Le Creuset in the 24th International Enamellers Congress in Chicago. Le Creuset showed the strong interests in our Cadmium red pigment series. They are quite willing to build up the long term cooperation with us. If you are also one of the enamel cookware manufacturer like them, you can contact with us, we will send you our best offer for our enamel pigments.


Ceramic porcelain frit

An ISO 9001:2001 certified ceramic porcelain frits manufacturer, we follow stringent guidelines for our supplier selection, porcelain frit technology and technical service standards.

We offer both leaded and no lead porcelain frit varieties available as transparent porcelain frits, glossy porcelain frits and matt porcelain frits designed specifically for double fast firing, single-fired monoporosa and porcelain stoneware ceramic coating applications.

Our specialty porcelain frits are ideal for ceramic coatings used in architectural ceramics, building ceramics, dinnerware and ceramic arts.

This article comes from ferro edit released

How to Test Acid Resistance Level for Enamels

The applications of acid resistant enamel coating is more and more widely, especially in mid and high level market. It’s not only applied in industrial area, where chemical resistance and long lasting durability against the elements is key, but also in our daily life, like enamel cookware and enamel water heater tank.

How to test acid resistance level for porcelain enamel coating?

Nolifrit follows a very serious and effective testing method for this.

Testing Reagent:

15% citric acid is used in this test. It’s reacted on the enamel coating surface and the result can be seen by virtual observation.

Testing Step:

1, Place some drops of citric acid liquid on enamel coating surface.

2, Cover the dropped enamel coating surface for 15 minutes.

3, Wash the test plate, to do the follow tests:


A, Visual Inspection

To inspect the two enamel coating areas directly by eyes. If there is obvious difference between the acid applied area and the regular enamel coating surface, the result is negative.

B, Pencil Test( dry)

Two parallel lines are drawn between the acid applied enamel coating area and the regular enamel coating surface by a pencil. Two lines are swabbed by a dry towel. If it is harder to swab the acid applied enamel coating area than the regular enamel coating area, the result is negative.

C, Reflection Test:

A light source is reflected on the acid applied enamel coating area and the regular enamel coating area. If there is a dim reflection on the acid applied enamel coating surface, the result is negative.


D, Pencil Test( wet)

The test in item B is applied by a wet towel. If it is harder to swab the acid applied enamel coating area than the regular enamel coating area, the result is negative.

Hunan Noli Enamel Co., Ltd is the leader manufacturer of porcelain enamel frit for vitreous enamel coating in China. Focused on enamel coating solutions for almost 30 years.

We have many kinds of enamel frit and enamel powder (ready to use powder and electrostatic powder) with high acid resistance level AA. They are widely used in enamel cookware, enamel storage tank, GGH(gas gas heater) and heater exchangers.

How to repair chipped enamel cookware

Porcelain enamel cookware often has a steel or cast iron base coated in a substance called vitreous enamel. Vitreous enamel is made by fusing melted glass to metal at a very high temperature. This smooth enamel coating protects the metal underlying your cookware. In many cases, the enamel chips over years of use or as a result of improper care. It’s possible to repair these chips or to seek a replacement piece if your enamelware is under warranty.

To repair your chipped porcelain enamel from scratch, purchase a food-safe epoxy. Use the epoxy to gently fill in the space left from where the vitreous enamel chipped away. Let the epoxy harden slightly, and then press a piece of waxed paper over it. Apply pressure to the waxed paper and flatten the epoxy against the cookware. Remove the waxed paper, and let the epoxy dry.

Once the epoxy has dried, you can use 400-grit sandpaper to gently sand the edges of the repaired area so they are flush with the surrounding edges. Take great care not to scratch the nearby enamel coating.

Using a food-safe enamel paint and a paintbrush, cover the epoxy area with a pigment as close in color to the original enamel as possible. Let it dry.

Once you’ve finished the repair process, be sure to wash your enamelware extremely thoroughly to remove all sand or other remnants of the repairs.

If you’re temporarily repairing your enamelware using the method outlined above, you should still plan to replace your cookware or get it professionally repaired for long-term use.

Hunan Noli Enamel Co., Ltd is the leader manufacturer of porcelain enamel frit and vitreous enamel powder in China. Focused on enamel coating for almost 30 years.

We can provide very professional vitreous enamel coating solutions for enamel cookware. We have many customers manufacture high level enamel cookware. Their product exported to EU and US market.

Enamel coating for undersea tunnel wall panels

On 23rd OCT, 2018, Hong Kong-Zhuhai-Macau Bridge opening ceremony is hold in Zhuhai, Guangdong. This bridge will be officially opened to traffic. After this, driving from Hong Kong to Zhuhai and Macau will only take 45mins. This provide much convenience for the residents and travelers both in Hong Kong, Zhuhai and Macau.


This bridge has very long undersea tunnel, the side wall of which is all decorated by vitreous enamel panels.

Vitreous enamel panels, also known as porcelain enamel panels, it’s corrosion resistant, fire resistant and high temperature resistant. Enamel coating thickness can be 0.5mm, and it’s of high weather resistance. Which can be kept for more than 100 years, without any fades even exposed to wind and rain.


Enamel coating is widely applied in our daily life. For example: cookware, oven, BBQ, bathtub and so on. Vitreous enamel panels is only one of the applications among these. Including enamel signage, mark, subway or undersea tunnel wall panels and architecture panels etc…

Hunan Noli Enamel Co., Ltd is the leader manufacturer of porcelain enamel frit and vitreous enamel powder in China. Focused on enamel coatings for almost 30 years.

We can provide very professional vitreous enamel coating solution for subway and undersea tunnel wall panels. Our ground coat frit A-9, A-10 and super white frit is specially designed for this field. The quality can be almost same with Japanese enamel frit manufacturer Tomatec and with much lower production cost. Which makes us the top one choice to replace them.

Noli Porcelain Enamel Solution for Oven Part

For customers who manufacture gas stove or oven part made by 0.5mm to thickness high quality low carbon steel, Nolifrit can supply them with high quality porcelain enamel frit meet with Europe RoHS and US FDA standard. Also with very nice heat resistance and thermal shock resistance. Effectively solved fish scale problem and at the same time, it has very strong adherence.

We also have one-stop solution service to supply you with suitable products, include our porcelain enamel frit, enamel pigment, milling additives, degreasant and adherence promoters. Those product can be purchased all together from Hunan Noli Enamel Co., Ltd.

We can offer technical guidance and after-sales service. Simultaneously, we can also customize the color and porcelain enamel coating for our customers. To satisfied the personalized requirements.


Typical Case:

One of the top 10 manufacturers of home appliance in Egypt.


Weak adherence of oven part

Nolifrit Solution:

Use three types of porcelain enamel frits (high+ mid+ low temperature) mixed,to expand the firing temperature range.

And prolong the firing time.


Problem solved after customer take our advice:


     Before(Weak adherence)                   After(Strong adherence)

Hunan Noli Enamel Co,. Ltd is the leader manufacturer of porcelain enamel frit and enamel powder in China. Focused on enamel coating for almost 30 years.

We can offer very professional technical guidance and product solutions. To solve the problems our customers will likely face in their production. We have successfully solved most of the problem of our customers, which makes us with very good reputation and build up the profound trust between us and our customers.