New paint emulsion colorants and mud preservatives active ingredients

Preventing microbial erosion is a common problem for water-based paint manufacturers throughout the United States and around the world. Bacteria pose a serious threat to the quality of the product, and if there is no effective anti-corrosion program, even some yeast and mold can cause the product to decay and decay. Microbial erosion and destruction can affect the performance of paints and coatings in a variety of ways, such as swelling tanks, unpleasant odors, viscosity changes, color changes, and more subtle changes, such as pH drift
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Under the Federal Pesticides, Fungicides, and Rodenticides Act (FIFRA), fungicides, including those coating preservatives, must be registered in the United States, first enacted in 1947, amended in 1972, and revised again in 1996 (U.S.C. No. 7. According to the EPA, "all pesticides distributed or sold in the United States must be registered with the EPA, and scientific data show that when used as directed on the product label, they do not pose an undue risk to human health, workers or the environment
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Table 1 shows some commonly used FIFRA-registered fungicide active ingredients that protect wet coatings in tanks from microbial erosion. Most of the active ingredients used in modern coating formulations have been registered for more than 40 years. It is important to note that registered fungicides are reviewed by the EPA every 15 years, and that more and more data on the environmental fate, ecotoxicity and exposure of microbicides need to be continuously registered at each review.
40 years after the coating has metamorphosed. One notable change was the 3-year ban on lead paint (16 CFR1303), issued by the U.S. Consumer Product Safety Commission, in September 1977, which came into effect in 1978
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. Other notable changes include the shift from solvent-based coatings to water-based coatings. Further, reducing the use of volatile organic compounds (VOCs) and increasing the use of circulating water and natural raw materials have had a significant impact on today's complex coating formulations. All of these positive changes have made coatings more environmentally friendly, and it's no surprise that they're more conducive to microbial growth , which, to be precise, thrives
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important commitment
coating manufacturers are looking for longer-acting coating preservatives to prevent common erosion damage, especially the resurrection of strains present in production facilities. However, the process of developing, testing and registering the active ingredient of a new fungicide is often costly - it can take years and millions of dollars. The new fungicide active ingredient is a useful supplement to the preservatives currently on the market, and the new preservatives will be needed: a broad spectrum of long-lasting protection against industrial-related contamination, including the resurrection of strains in isolated production, the release of formaldehyde and cotton-mixed alcohols, compatibility with coatings and raw materials, certification by most eco-markers, and suitable for use in low VOC coating formulations.
when discussing the feasibility of introducing new coating preservatives, there are a number of factors to consider. In accordance with FIFRA regulations, fungicides are regulated and managed by the U.S. Environmental Protection Agency (EPA). EPA requirements include: acute, chronic and ecotoxicity; environmental fate; physical/chemical properties; and the efficacy of recommended preservative products. Even new combinations of previously registered active ingredients (see Table 1) still require extensive review before re-entering the market before they can be approved for registration. For new products previously approved for the same end use (e.g. coating preservative BIT), the standard schedule for reviewing product files can be as little as 5 months. However, for new active ingredients, as well as products containing these new active ingredients, it takes a long time - usually 18 months. Meeting the data required for registration can greatly affect the financial data of the registered company and require significant time to complete all the necessary scientific research.
The first new coating antiseptic active ingredient of the century
Dow Chemical is expected to register a new active fungicide, N-methyl-1, 2-benzodiaxone-3 (2H)-ketone (MBIT), with the U.S. Environmental Protection Agency in 2014. The entire registration process requires millions of dollars over a multi-year period. As expected, the largest investment in registering MBIT in the United States is the toxicology database, which accounts for more than 90% of the total cost.
to conduct extensive MBIT efficacy testing of industrial-related bacteria, yeasts and molds in a variety of coatings, colorants, lotions and mineral mud formulations before EPA registration. What is striking is the comparison of the performance of MBIT with the active ingredient 1,2-benzodiaxone-3-ketone (BIT) of paint antiseptics with commonly used structures. In the anti-corrosion test of colorants, MBIT showed an increase in activity against yeast compared to BIT, and showed equal or better results in bacterial tests. Figure 1a shows the antibacterial efficacy of four challenges for three colorants, using laboratory strains (5×106 CFU / mL). Blue colorants with the same concentration of BIT and MBIT (total active ingredient 125ppm) can successfully prevent corrosion. In addition, the use of 125 ppm MBIT alone makes yellow and red formulations effective against corrosion, while preventing bacterial corruption requires high concentrations of BIT (250 to 500 ppm) to protect these colorants. Similar results were shown in the evaluation of the use of BIT and MBIT in colorants to prevent yeast (Figure 1b), which achieved corrosion protection at 125 ppm of the total active ingredient. For blue colorants, the concentration of BIT required to achieve the same effect is twice (250 ppm) and for yellow and red colorants, the concentration of BIT required to achieve the same effect is four times (500 ppm). Five of the six colorant trials conducted demonstrated that MBIT produced excellent results at lower active concentrations and observed the same performance in the remaining trials.
the excellent antiseptic properties of MBIT are not limited to colorants. The antibacterial properties of the two active ingredients were evaluated in titanium dioxide (TiO2) and calcium carbonate (CaCO3) mineral mud. After four bacteria were inoculated, the efficacy difference was significant, with a BIT of 500 ppm (0.05%) not being able to protect against corrosion in neither of the two mineral muds, while MBIT of 250 ppm and 125 ppm prevented corruption of titanium dioxide and calcium carbonate mineral mud (Figure 2).
launched MBIT
in the U.S. once the EPA registration is approved, in 2014 Dow's Microbiological Control Technology Division will launch a new preservative product BIOBAN™557 fungicide. BIOBAN 557 contains new active ingredients, N-methyl-1, 2-benzodiaxone-3 (2H)-ketones (MBIT) and 5-chlorine-2-methyl-4-isoprene-3-ketones (CMIT) and 2-methyl-4-isopyroid-3-mixed, containing 10% of the total active ingredient, to obtain the best broad-spectrum antibacterial effect by adjusting the three active ingredients for industrial-related bacteria, yeast and mold, including resurrected strains. Using the patented TAUNOVATESM Efficient Microbiological Quantitative Testing (HTP) system (Figure 3a) of dow's Microbiological Control Technology Business Unit, the formulation of MBIT/CMIT/MIT is finalized by extensive testing in coatings and other substituts. The system uses robots to assist in sample analysis and can provide 13,000 simultaneous test data points in a day. Its efficiency is equivalent to the laboratory work of 15 consecutive working days working 8 hours a day using standard non-robot test methods (including petri dishes and sample cups) (Figure 3b).
prevent bacteria and fungi
the prevalence of low VOC coating formulations, the demand for powerful anti-corrosion strategies is increasing. Manufacturers reported an increase in the rate of microbial contamination of their equipment, particularly low VOC products and products containing natural raw materials. Due to these factors, coupled with the American coating season is in the warm summer, for microorganisms to provide ideal growth conditions. To combat microbial erosion, manufacturers are often forced to use a variety of single active preservative products in order to successfully achieve coating corrosion protection. To illustrate the efficacy of the new 10% MBIT/CMIT/MIT product relative to a single active product (e.g. 1.5% CMIT/MIT and 19% BIT), the four-cycle bacterial challenge trial of the hard-to-save latex paint (pH 8.5) was evaluated using the TAUNOVATE HTP system. The HTP test results are in Table 2.
four-cycle bacterial challenge trials using industry-related strains, 10% of MBIT/CMIT/MIT products were more efficient than single active BIT and CMIT/MIT products. After 5 × 106CFU/mL of bacteria, the green shaded portion indicates a pass score, while the red shaded portion indicates a failed score. Using 2367ppm products, MBIT/CMIT/MIT products passed a one-month challenge trial with 236.7ppm MBIT/CMIT/MIT. BIT and CMIT/MIT single active products passed the tests when the EPA specified the maximum usage of 2500PPM (BIT of 475 PPM) and 1675 ppm (25 ppm of CMIT/MIT) respectively. Although effective in this trial, when production conditions, especially those related to industrial hygiene, can lead to the failure of a single active preservative. There is no margin of error for the results reported in Table 2. Conversely, there is sufficient space between the 2367ppm MBIT/CMIT/MIT product tested and the expected upper limit of the 3700ppm MBIT/CMIT/MIT product (EPA registration), which provides 370ppm MBIT/CMIT/MIT activity.
the excellent efficacy of MBIT/CMIT/MIT mixtures against fungi has been documented. Although fungal contamination of liquid coatings is not as common as bacterial contamination, the rate of reported by manufacturers continues to increase. The MBIT/CMIT/MIT product was evaluated against a single active BIT product and a 95ppm BIT with a different amount of CMIT/MIT product portfolio, and a three-cycle fungal challenge test was conducted in a hard-to-save latex paint (pH 9.0) sample containing 1.5% CMIT/MIT. Samples are inoculated weekly against specialty yeasts and industrial-related laboratory mold strains in coating production. The results can be found in Table 3. MBIT/CMIT/MIT has been successful in coatings with the expected lower usage limit (previously registered with EPA), i.e. 900 ppm (0.09%) of products with a total MBIT/CMIT/MIT of 90ppm. Use BIT alone and fail at 380ppm. Most notably, a combination of 25ppm CMIT/MIT (available from 1.5% CMIT/MIT products at 1675 ppm) and 95ppm BIT, with a total active group of 120ppm, failed. These results demonstrate that only the unique ratios of MBIT, CMIT, and MIT in MBIT/CMIT/MIT products can demonstrate efficacy.
rapid sterilization and long-lasting corrosion
microbial contamination events occur in coating production processes, and pollution occurs frequently in the summer. Product rework is an important solution due to the low sensitivity of VOC water products and the high cost of handling contaminated batches of products. Typically, the rework process involves the use of quick-acting disinfectants, such as products containing DBNPA. When disinfectants are added, there is a mix, hold, microbial monitoring and eventually long-lasting preservatives added to the new production batch. This time-consuming process requires several steps, and coating manufacturers have been looking for ways to simplify it.
in the early stages of MBIT/CMIT/MIT showed that severely contaminated samples had rapid de-fouling capability. More subsequent studies are available in Table 4, where samples of heavily contaminated coatings are provided by manufacturers who are seeking advice and methods for effective remediation and long-lasting corrosion protection of highly sensitive coating formulations after being eroded by resurrectable prosthetic monocytobacterium isolated from the equipment. MBIT/CMIT/MIT, which uses 370ppm at a time, can successfully de-foul coatings that are subject to four other challenges and provide long-lasting corrosion protection. The combination of DBNPA/CMIT/MIT, CMIT/MIT/mixed cotton alcohol and DBNPA/CMIT/MIT/mixed cotton alcohol has no de-fouling and long-lasting anti-corrosion effect. The combination of DBNPA/CMIT/MIT/BIT successfully purifys and protects the coating, but the total microbicide concentration required is 900 ppm of active components (6175ppm products), which is significantly higher than the MBIT/CMIT/MIT (3700ppm product) required to achieve approximate corrosion resistance.
combination of rapid sterilization and long-lasting anti-corrosion effects was measured against other types of formulations and resistance to various microorganisms. Table 5 shows the results of acrylic emulsions that are heavily contaminated with yeast. The use of 3000ppm MBIT/CMIT/MIT (MBIT/CMIT/MITT for 300ppm) enables rapid and successful de-fouling of emulsions at speeds of more than 200ppm dbPA, while providing long-lasting corrosion protection for five other challenges. BIT is not a fast-acting fungicide, but 380 ppm does not give emulsion long-lasting corrosion protection.
CMIT/MIT is considered to be the fastest-acting isopyroid chemical. A study was conducted in contaminated colorants in which CMIT/MIT was combined with a medium dose of DBNPA, a rapidly disinfectant chemical. Of all seven challenges with (5×106 CFU/ml) yeast, the 300ppm MBIT/CMIT/MIT combination provides the same sterilization rate and exceeds the CMIT/MIT/DBNPA combination. The results are in table 6.
ongoing laboratory tests
U.S. manufacturers of aquatic products can contact Dow's Microbiological Control Technology Business unit to request a laboratory sample for MBIT/CMIT/MIT formulations