Difficulties and directions in the development of solvent-based fluorocarbon coatings
Due to the severe situation of environmental protection, the requirements of the country for environmental protection are becoming stricter and stricter currently, especially for the emission of VOC from organic solvents.

(1) The State Ministry of Finance issued the "Notice on the Collection of Consumption Tax on Batteries and Coatings" on January 28, 2016, which imposes a 4% consumption tax on the paint (under construction) with VOC content > 420g/L. In the next step, the sewage charges will be charged basing on VOC emission.

(2) National and local environmental protection authorities have gradually banned the construction of new or expanded solvent-based products, so as to maximize the control and reduction of VOC emission.

(3) The new environmental protection law, which is known as "the most stringent in history" has also been fully implemented on January 1, 2017.

Therefore, solvent-based coatings will gradually be replaced by water-based coatings and powder coatings. However, after long-term development and development of water-based coatings, there are still many technical difficulties to be solved and overcome, in addition, water-based coatings also have the problems of VOC treatment and wastewater slag treatment, therefore, we believe that the replacement of solvent-based coatings with powder coatings will be the mainstream direction of the current market and the future development of the industry.

Under this background and vision, after long-term research and development and experimentation, KGE has introduced a new eco-friendly fluorocarbon powder coating that can replace solvent-based fluorocarbon coatings.
Advantages and disadvantages of fluorocarbon powder coatings
  • (1) Fluorocarbon powder coating is solid powder, completely free of any solvent, does not produce any organic waste gas and waste water during production and construction, not only meets environmental protection requirements, but also saves treatment costs such as waste gas and waste water;
  • (2) Different from the solvent-based fluorocarbon coating during construction, it can be directly used without mixing and can reduce labor costs;
  • (3) Compared with solvent-type fluorocarbon coatings, the electricity consumption is low during construction, which can save costs;
  • (4) It only needs once coating, the process is convenient to operate without the need of adding production equipment;
  • (5) The construction process can adopt not only horizontal spraying but also vertical spraying, which can reduce more costs with vertical spraying;
  • (6) Fluorocarbon powder coatings have many problems and defects due to metallic color, and it is temporarily unable to replace solvent-based metallic fluorocarbon coating.
Fluorine modified powder coatings
KOFLUX-CLASS II -1 fluorocarbon powder coating is made by mixing fluororesin with super weather resistant polyester as well as inorganic ceramic pigments with special treatment. It solves the problem of adhesion of aluminum alloy surface, which has excellent weather resistance, corrosion resistance and good mechanical properties, and its performance fully meets or exceeds AAMA2604 standard.
Because the fluorine modified polyester carbon powder coating is a thermosetting powder coating, it can be transferred to woodgrain compared with PVDF fluorocarbon powder coating, which makes it more widely used.
PVDF fluorocarbon powder coating
KOFLUX-CLASS II -2 fluorocarbon powder coating is made of 70% or more PVDF cyanide resin and our company's self-developed high weather resistance, high adhesion acrylic resin and inorganic ceramic pigment liquid after frozen to -180°C with liquid nitrogen and then cryogenically pulverized, and its product performance fully meets or exceeds the AAMA 2605 standard.
img

Product Performance

Coating VarietyProduct DescriptionProduct StandardWarranty Period
Liquid acrylic coatings/Liquid polyester coatings/Powder polyester coatingsHigh quality polyester,used for outdoor.
AAMA2603
Qualicoat ClassⅠ
5 years warranty
Super durable powder coatings
High durable resin and inorganic pigments,used for outdoor high buildings.
AAMA2603
Qualicoat ClassⅡ
10 years warranty
Fluorine modified polyester powder coatings
High durable resin and inorgainic pigments,used for outdoor high buildings.
AAMA2604
Qualicoat Class
15 years warranty
PVDF Fluorocarbon coatings/PVDF Fluorocarbon powder coatings70% PVDF resin and inorganic pigments,most durable coating so far.
AAMA2605
Qualicoat Class Ⅲ
20-30 years warranty

Introduction to PVDF fluorocarbon coating

PVDF fluororesin coating is a kind of high-grade decorative material with super weather resistance, acid and alkali resistance made of polyvinylidene fluoride (PVDF) resin and acrylic resin plus inorganic composite pigment.
According to experiments and practice, it boasts more than 20 years of super weather resistance, and is mainly used in aluminum alloy profiles, aluminum doors and windows, aluminum curtain walls and so on.

The difference between PVDF fluorocarbon coating and other fluorine coatings

  • Polymonofluoroethylene is referred to as PVFUses: Mainly used in solar back film, made into coating for the internal coating of metal packaging, anti-corrosion effect.

    pvf

  • Polyvinylidene difluoride is referred to as PVDFUses: Solar back film, anti-chemical injection molded body, the coating made of it is used for decorating and improving the weather resistance (durability) of aluminum profile and aluminum curtain wall.

    pvdf

  • Polytrifluorochloroethylene is referred to as PEVEUses: The liquid-based coating made of PEVE is used for coating the steel surfaces, and the powder coating made of PEVE is used for decorating the metal surface.

    peve

  • Polytetrafluoroethylene is referred to as PTFEUses: It is used as fillers or sanding agents for powder coatings, the coating made of it is used for cooking iron or stainless steel pots, usually called non-stick pan.

    ptfe

Principle of weather resistance: the the fluorocarbon bond of fluorocarbon resin is the most stable chemical bond in the fluorocarbon bond organic synthesis compounds

a. The binding force of the fluorine-carbon (F-C) bond between the fluorine (F) and carbon (C) atoms with the largest negative charge is as high as 105.4 kcaI/mol, which means that it requires at least above 105.4 kcal/mol energy todestroy the fluorine-carbon (F-C) bond.

b. The bonding distance of the fluorine-carbon (F-C) bond is 1.36 A, which is shorter than the carbon-carbon (C-C) bonding distance of 1.54 A. Due to the steric hindrance generated by the fluorine atom, the structure is very tight and it is difficult to break the fluorine-carbon (FC) bond.

Reasons of color durability: the difference between inorganic composite pigments and organic pigments

  • A. Inorganic composite pigmentInorganic substances are always existing in nature (substances which are free of carbon are inorganic substances, and substances which contain carbon are organic substances), such as all metals including Fe, Cu, Ti, Li, Mn, Co, and so on. Inorganic composite pigments are made by high temperature calcination of these metals.
    Inorganic composite pigmentUnit price (yuan/kg)Organic pigmentUnit price (yuan/kg)
    Black (Cu, Fe, Cr, Mn)Adding 15% in 100Carbon blackAdding 4% in 20
    Yellow (Li, Ti) nickel titanium yellow65Iron yellow7
    Red (Cr) chrome red300Iron red7
    Blue (Co, Li) cobalt blue300Titanium blue50
    Green (Co) cobalt green300Titanium green50
  • B. Aluminum powder, pearl powdersThe aluminum powder and pearl powders used for fluorocarbon coating are capsulated, the weather resistance grade is higher, and the unit price is also relatively expensive.
  • C. 70% of the fluorocarbon coatingFluorocarbon resin itself cannot form a film, and it needs to be used together with the acrylic resin to exert its weather resistance.