Novel In-Can Biocides with Global Regulatory Compliance

Rodney T. Rees

THOR Specialties, Inc50 Waterview DriveShelton, CT 06484

www.thor.com

October 25-28, 2015

Modern day coatings formulations are more susceptible to microbiological spoilage than older formulations

• Antimicrobial effect of VOC, free monomer and biocide carry over from liquid / dispersed components is now significantly decreased

• Wash water re-use and bulk stored liquids with decreased biocide content can cause increased bioburden in coatings and select for more hardy organisms

• Coating Biocide needs to perform better than past versions.

CurrentPre 2000

Antimicrobial influence from VOC, free monomer and biocide carry over from aqueous components/ dispersions (excluding water).

• Selection of most appropriate biocide system is essential• Performance requirements• Compliance / marketing requirements

• Formulator requires more knowledge of biocide actives• Stability• Efficacy profile

• Formulator requires basic microbiological knowledge

• Biocide manufacturers / partners have to:• Come up with novel & practical preservation concepts

• Work closely with coating formulators on the best solutions.

Nett Result: Formulators need to pay far more attention to the Coating Biocide as an essential functional ingredient

Few traditional in-can biocide molecules to choose from: 80% of current formulations preserved with:

Molecule Efficacy /Stability

5-chloro-2-methyl-4-isothiazolin-3-one (CIT) B, F High kill rate / limited stability

2-methyl-4-isothiazolin-3-one (MIT) B (F) Less rapid kill / good stability

1,2-benzisothiazolin-3-one (BIT) B (F) Less rapid kill / good stability

2-bromo-2-nitropropane-1,3-diol (BNPD) B (F) Mod kill rate / limited stability

Formaldehyde – donors (various) B (F) Mod kill rate / variable stability

• No single active ingredient has all the essential / desired characteristics• Active ingredients have differing stabilities in different formulations

• Electrophilic organic molecules• Carefully considered BLENDS of actives are the best Final Formulation

option (spectrum & synergy) … but even this may not be enough in modern high susceptibility formulations!

• Truly “New” actives are unlikely in the near future.

B = Bactericidal F = Fungicidal

Factors influencing in-can biocide stability / availability:

pH ORP

Nucleophiles

Heat compatibility

Other Factors:•Stage of addition during manufacture•Pest pressure (plant and raw materials)•Regulatory / labeling implications (use level restriction)

Predominant Organisms Associated with Major Spoilage:

• Pseudomonas & related genera• Other Gram-Negative Bacteria• Gram-Positive Bacteria• Yeasts & Molds [fungi]

80 %

5 %15 %

• Pseudomonas aeruginosa• Pseudomonas putida• Burkholderia cepacia• Alcaligenes spp

• Candida spp

Adaptive / Problematic Species:

The chosen biocide must at least be effective against these organisms.

More Stringent Regulatory Requirements:

Not applicable to properly formulated biocide blends in end-use product

EUROPE:

CLP Regulation 1272/2008/EC – 2nd Adaptation to Technical Progress (aka EU H208) is currently the most restrictive regulation - designed to protect people with existing allergies to certain chemistries.

Above a Specific Concentration Limit (SCL) the following statement is required:

Contains “name of relevant substance”. May produce an allergic reaction

GHS Pictograms (Includes USA):

EU H208 – in force since June 2015

•Concentrations of compounds known to be sensitizers with a known SCL will require cautionary labeling above 1/10 their SCL

Single actives below label limit are inadequate for preservation

•Blends at the maximum allowable limit below 1/10 SCL offer protection above & beyond single actives, but even this may not be adequate … more innovative technology is required … led to development of New Novel Biocides•Need to consider biocide in all raw materials, since the regulation applies to the total biocide compliment of the end product.

Active IngredientSensitizer Category

(SCL)Concentration requiring

labelling (ppm)

CIT/MIT 1 (15 ppm) >/= 1.5

BIT 1 (500 ppm) >/= 50

MIT 1 (1000 ppm) >/= 100

BNPD Not Categorized No Limit*

Formaldehyde Donors 1 (10,000) 1000

*High level can cause discoloration or affect cross-linking

EU H208 Regulation & the USA

• The USA domestic coatings market is not impacted by the H208 regulation• Only products manufactured in the USA destined for the EU or markets that

will follow the EU are affected

However:

• Similar restrictions may be imposed in the USA in years to come• The US coatings market can take advantage of the successful new biocide

innovations with a validated performance history.

In-can Biocide Progression Timescale:

Current Biocide vs New Novel Biocides (H208-compliant) MIC - % Biocide:

% B

ioci

de

New Novel In-Can Biocide – Performance examples:

Example 1 Construction Chemical

Only the New Generation Biocide passed all challenge testing without the EU cautionary labeling requirement.

Biocide Actives Mold Growth

Viable spores Yeast

(4 wk) (4 wk) (4 wk)

Blank Fai l Fa i l Fa i l 0

MIT/BIT/CIT (Trad) Pass Pass Pass 80 Yes

MIT/BIT/BNPD (Trad) Fai l Fa i l Pass 130 No

BIT/ZPT (Trad) Pass Pass Pass 115 Yes

Novel New Biocide Pass Pass Pass 50 No

0 1 2 3 4 No. Inoculations passed

Bacterial Testing ppm Biocide

H208 Label

Example 2 Carbon Black Dispersion (known to be difficult to preserve):

Only the New Novel Biocide passed all challenge testing without the EU precautionary labeling requirement.

Biocide Actives Mold Growth

Viable spores Yeast

(4 wk) (4 wk) (4 wk)

Blank Fai l Fa i l Fa i l 0

MIT/BIT (Trad) Fai l Fa i l Fa i l 200 Yes

MIT/BIT/BNPD (Trad) Fai l Fa i l Fa i l 260 Yes

New Novel Biocide Pass Pass Pass 199 No

0 1 2 3 No. Inoculations passed

Bacterial Testing ppm Biocide

H208 Label

Example 3 Surface Coating A:

M-BIT = Methyl BIT / DTBMA (dithio-bis-methyl amide)

Only the New Novel Biocide passed all challenge testing without the EU precautionary labeling requirement.

Biocide Actives Yeast (Candida)

(8 cycles )

Blank Fai l 0

MIT/BIT (Trad) Fai l 150 Yes

MIT/M-BIT (Trad) Fai l 67 No

MIT/M-BIT (Trad) Fai l 88 No

BIT/ZPT (Trad) Pass 115 Yes

New Novel Biocide Pass 75 No

0 2 4 6 8 No. Inoculations passed

Bacterial Testingppm Biocide

H208 Label

Only the New Novel Biocide passed all challenge testing without the EU precautionary labeling requirement.

Example 4 Surface Coating B:

Biocide Actives Blank 0

MIT/BIT/BNPD (Trad) 130 No

CIT/MIT/BIT (Trad) 240 Yes

New Novel Biocide 100 No

0 1 2 3 No. Inoculations passed (3 tested)

Bacterial Testingppm Biocide H208 Label

Blank did not display susceptibility to yeasts and molds

Only the New Novel Biocide passed all challenge testing without the EU precautionary labeling requirement.

Example 5 Adhesive:

Summary / Conclusions:

• Modern Coatings are more susceptible than older formulations

• Coatings formulators are required to have much more knowledge of biocides and spoilage organisms than in the past

• Modern biocides need to perform better than previous versions to cope with• Greater susceptibility• Adapted / stronger organisms

• Biocide Blends comprising two or more actives may no longer be enough – greater innovation is required in an increasingly regulated industry

• New Novel In-can Biocides are available to cope with the demands of modern coatings formulations & evolving wild strain organisms, whilst conforming to the stringent regulatory boundaries

• These biocides are already being used in Europe, and will be available in the USA in 2015.

Thank you for your attention!

www.thor.com