biocide optimization: an assessment of rapid kill...

Biocide Optimization: An Assessment of Rapid

Kill Preservatives and Two Novel Chemistries

Beth Ann Browne, Ph.D.

Dow Microbial Control

October 22, 2013

DOW CONFIDENTIAL - Do not share without permission

2

Outline

Paints Today

Speed vs. Endurance and Rapid-Kill vs. Long-Term

Preservatives

Benefits of Preservative Combinations

The Chemistries, Including Two Novel Active Ingredients:

MBIT (2-Methyl-1,2-Benzisothiazolin-3-one)

DBMAL (2,2-Dibromomalonamide)

Time-Kill and In-can Challenge Test Efficacy Data

Paint

Wash Water

Float Solution

Summary


Buffalo Grove,

Illinois, USA

DMC Center of

Excellence:

Microbiological

Methodology

Shanghai, China

Singapore Mumbai, India São Paulo,

Brazil

Dubai, United

Arab Emirates

Querétaro,

Mexico

Acknowledgements:

Colleagues from Dow Microbial Control Regional Microbiology Laboratories and

R&D Centers of Excellence

Buchs,

Switzerland

DMC Center of

Excellence:

Formulations

Spring House,

Pennsylvania, USA

DMC Center of

Excellence: Actives

Delivery

Soma, Japan

Warsaw, Poland

Altona, Australia

3



4

Today’s State of the Art

Paint Formulations…

Are more susceptible to microbial contamination due to:

Use of more sustainable ingredients, including naturally derived raw

materials

Lower volatile organic compound (VOC) levels

Increased water content

But, preservative choices are limited by:

Global registration status

Compatibility with final products and raw materials

Antimicrobial efficacy spectra, including resilient microorganisms

present in the manufacturing environment

Prevention of microbial contamination is a critical objective.


5

A Preservative Choice?

Stephen Kiprotich

2012 Olympic Marathon

2:08:01

Speed or Endurance?

Usain Bolt

2012 Olympic 100 Meter

9.63 seconds

Manufacturers’ answer:

Yes…BOTH!


6

There IS a Difference:

Preservative: An antimicrobial that provides long-term protection of a product to prevent it from becoming contaminated under repeated bacterial or fungal assaults.

Rapid Kill Antimicrobial: An antimicrobial that provides a rapid reduction in the number of viable microorganisms, but does not offer long-term protection.

Rapid Kill ≠ Long-Term Preservative

The Benefits of Combinations

Rapid Kill Chemistry:

Quick decontamination of raw materials and products

during the manufacturing process

Efficacy against resilient manufacturing isolates

Fill-in efficacy gaps of certain long-term preservatives

(ex: BIT and Pseudomonas sp.)

Reduce microbial load so that long-term preservative is

maintained…for the long-term

Long-term Chemistry:

Provides extended protection against contamination

Protects the product from customer use (and some misuse)


7

Rapid Kill + Long-Term Preservative = Robust Protection


8

The Chemistries (The Racers):

Speed

Typical

Human Usain Bolt The Cheetah

C

CC

N

O

NH2

BrBr

2,2-Di-bromo-3-nitrilo-propionamide

CMIT/MIT

SNH

O

BIT

MBIT

2,2-Dibromomalonamide

NH2 NH2

O O

Br

Br

Dibromomalonamide

NH2 NH2

O O

H2O

NH2 OH

O O

Malonamide

Malonamic acid

Malonic acid

CO2 and H

2O

H2O

NH2

O

Br

Br

Dibromoacetamide

H2O

OH

O

Br

Br

Dibromoacetic Acid

+ NH3

OH

O

H

O

+ 2 Br-

Glycolic Acid

Air

OH

O

OH

O

Oxalic Acid

H2O

Abiotic hydrolysis Nucleophilic biotic reactions

UV light

+ 2 Br-

+ NH3

+ NH3

S

N CH3

O

2-Methyl-1,2-

Benzisothiazolin-3-one

1,2-Benzisothiazolin-3-one

5- Chloro-2-Methy-4-

isothiazolin-3-one & 2-Methy-4-isothiazolin-3-one

DBNPA

DBMAL


9

Two New Biocidal Chemistries...

Speed

Usain Bolt The Cheetah

C

CC

N

O

NH2

BrBr


CMIT/MIT

SNH

O

BIT

MBIT


NH2 NH2

O O

Br

Br

Dibromomalonamide

NH2 NH2

O O

H2O

NH2 OH

O O

Malonamide

Malonamic acid

Malonic acid

CO2 and H

2O

H2O

NH2

O

Br

Br

Dibromoacetamide

H2O

OH

O

Br

Br

Dibromoacetic Acid

+ NH3

OH

O

H

O

+ 2 Br-

Glycolic Acid

Air

OH

O

OH

O

Oxalic Acid

H2O


UV light

+ 2 Br-

+ NH3

+ NH3

S

N CH3

O

2-Methyl-1,2-


1,2-Benzisothiazolin-3-one

5- Chloro-2-Methy-4-

isothiazolin-3-one & 2-Methy-4-isothiazolin-3-one

DBNPA

DBMAL

Typical

Human

BIT vs. The Novel Active MBIT


10

0

100

200

300

400

500

Eff

ec

tive

Co

nc

en

tra

tio

n

(pp

m a

cti

ve

)

TiO2

CaCO3

BIT MBIT

> 500 > 500

250

125

MBIT is more efficacious against bacteria in two different

mineral slurry formulations:

TiO2

CaCO3

MBIT protects the TiO2 and CaCO3 slurries from four bacterial challenges over

27 days with 250 ppm and 125 ppm, respectively.

BIT vs. MBIT in Colorants


11

MBIT is more efficacious against bacteria after four challenges:

MBIT is more efficacious against yeast after three challenges:

0

100

200

300

400

500

Eff

ec

tive

Co

nc

en

tra

tio

n

(pp

m a

cti

ve

)

Blue Colorant

Yellow Colorant

Red Colorant

BIT MBIT

0

100

200

300

400

500

Eff

ec

tive

Co

nc

en

tra

tio

n

(pp

m a

cti

ve

)

Blue Colorant

Yellow Colorant

Red Colorant

BIT MBIT


12

Two New Biocidal Chemistries...

Speed

Usain Bolt The Cheetah

C

CC

N

O

NH2

BrBr


SNH

O

BIT

MBIT


NH2 NH2

O O

Br

Br

Dibromomalonamide

NH2 NH2

O O

H2O

NH2 OH

O O

Malonamide

Malonamic acid

Malonic acid

CO2 and H

2O

H2O

NH2

O

Br

Br

Dibromoacetamide

H2O

OH

O

Br

Br

Dibromoacetic Acid

+ NH3

OH

O

H

O

+ 2 Br-

Glycolic Acid

Air

OH

O

OH

O

Oxalic Acid

H2O


UV light

+ 2 Br-

+ NH3

+ NH3

S

N CH3

O

2-Methyl-1,2-


1,2-Benzisothiazolin-3-one DBNPA

DBMAL

Typical

Human

DBNPA vs. the Novel Active DBMAL


13

DBMAL:

Derived from DBNPA

Formulated product is very stable (>2 years)

Stable in high pH solutions with persistent kill

Very effective in first market targeted– industrial water

treatment

Available in a liquid form

Expected EPA registration submission in 2014 for

Industrial Water Treatment

Currently being evaluated in other markets

Speed

DBMAL DBNPA

The Race: 100 Meters + 26.2 Miles

Measuring Preservative Performance Against

Bacteria in Paint, Wash Water, and a Float Solution


14

Time-Kill Assay

(The 100 Meter Sprint)

Used to determine the threshold concentration of biocide required to rapidly decontaminate contaminated materials.

Evaluates time-dependent bactericidal efficacy.

Procedure:

Test sample is inoculated with a pool of industrially relevant bacterial organisms at a concentration of 5 x 106 CFU/mL.

A series of biocide concentrations is established in separate aliquots of the spoiled product.

At specific time points, measured volumes of the sample are removed and biocide is neutralized.

Viable organisms are enumerated.

Time points: 0.25, 0.5, 1, 4, and 24 hours.


15

Bacterial Challenge Test

(The Marathon)

Used to determine the threshold concentration of biocide

required to protect the consumer product (ex: paint) from

bacterial spoilage.

Procedure:

A series of biocide concentrations are tested.

Test sample is challenged by inoculating it with a pool

of industrially relevant bacterial organisms at a

concentration of 5 x 106 CFU/mL.

At specific time points post inoculation and

subsequent reinoculation, measured volumes of the

sample are removed.

Viable organisms are enumerated.


16

Organisms and Scoring Scale


17

Bacteria Pool 1 (Laboratory strains)

•Alcaligenes faecalis (ATCC #8750)

•Pseudomonas aeruginosa (ATCC #10145)

• Pseudomonas aeruginosa (ATCC #15442)

• Staphylococcus aureus (ATCC #6538)

•Enterobacter aerogenes (ATCC #13048)

•Pseudomonas fluorescens (ATCC #17397) Plus…

Bacteria Pool 2 (Environmental Pseudomonas sp.)

• Pseudomonas aeruginosa (spoiled rheology modifier)

• Pseudomonas aeruginosa (spoiled process water)

• Pseudomonas aeruginosa (spoiled low VOC paint)

• Pseudomonas oleovorans (contaminated equipment)

Plating Results Score Approximate CFU/mL

No detectable colonies 0 < 1 x 101

1–9 colonies 1 1 x 101 - 9 x 101

10–99 colonies 2 1 x 102 – 9.9 x 102

100–300 colonies 3 1 x 103 - 3 x 103

>300 colonies (smear) 4 > 3 x 103

Scoring Scale:

Pass

Fail

Low VOC Paint

DOW CONFIDENTIAL - Do not share without permission 18

20% DBNPA product (ppm)/ DBNPA (ppm

a.i.)

24

hr.

Pre

-In

ocu

lati

on

Time Post Biocide Addition (hours)

Re-

Ino

cula

tio

n

Hours post Re-Inoculation

Re-

Ino

cula

tio

n


Re-

Ino

cula

tio

n


0.25 0.5 1 4 24 4 24 168 24 168 24 168

2000 / 400 2 2 1 0 0 4 2 0 3 0 3 0

1000 / 200 2 2 2 0 0 4 3 0 4 4 4 4

500 / 100 2 2 2 0 0 4 4 4 4 4 4 4

250 / 50 2 2 2 0 0 4 4 4 4 4 4 4

125 / 25 2 2 2 0 0 4 4 4 4 4 4 4

0 3 3 2 3 2 4 4 4 4 4 4 4

12% DBMAL product (ppm) / DBMAL (ppm

a.i.)

24

hr.

Pre

-In

ocu

lati

on


Re-

Ino

cula

tio

n


Re-

Ino

cula

tio

n


Re-

Ino

cula

tio

n


0.25 0.5 1 4 24 4 24 168 24 168 24 168

5000 / 600 2 2 2 0 0 4 3 0 4 4 4 4

3333 / 400 2 2 2 0 0 4 3 4 4 4 4 4

1666 / 200 2 2 2 1 0 4 4 4 4 4 4 4

833 / 100 2 2 2 0 0 4 4 4 4 4 4 4

417 / 50 2 2 2 1 0 4 4 4 4 4 4 4

280 / 33.6 2 2 2 2 0 4 4 4 4 4 4 4

0 3 3 2 3 2 4 4 4 4 4 4 4

1.5% CMIT/MIT product (ppm) /

CMIT/MIT (ppm a.i.)

24

hr.

Pre

-In

ocu

lati

on


Re-

Ino

cula

tio

n Hours post

Re-Inoculation R

e-In

ocu

lati

on


Re-

Ino

cula

tio

n Hours post

Re-Inoculation

0.25 0.5 1 4 24 4 24 168 24 168 24 168

1675 / 22.5 2 2 2 2 0 3 0 0 0 0 0 0

0 3 3 2 3 2 4 4 4 4 4 4 4

10% MBIT/CMIT/MIT product (ppm) /

MBIT/CMIT/MIT (ppm a.i.)

24

hr.

Pre

-In

ocu

lati

on


Re-

Ino

cula

tio

n


Re-

Ino

cula

tio

n


Re-

Ino

cula

tio

n


0.25 0.5 1 4 24 4 24 168 24 168 24 168

3700 / 370 2 2 2 1 0 1 0 0 0 0 0 0

1850 / 185 2 2 2 1 0 3 0 0 4 4 4 4

0 3 3 2 3 2 4 4 4 4 4 4 4

DBNPA is fastest with efficacy

in 1-4 hours after the first

challenge.

DBMAL was fast, but did not

provide long-term efficacy.

CMIT/MIT showed efficacy in

24 hours and provided long-

term efficacy.

MBIT/CMIT/MIT combo

product was fast with efficacy

in 4 hours and provided long-

term protection.

Wash Water



in 4 hours after the first

challenge.

DBMAL was fast (24 hours)

and provided long-term

efficacy.

CMIT/MIT was slow, but

provided long-term efficacy.

MBIT/CMIT/MIT combo


in 24 hours and provided

long-term protection.

20% DBNPA product (ppm)/ DBNPA (ppm a.i.)

24

hr.

Pre

-In

ocu

lati

on


Re-

Ino

cula

tio

n

Time Post Re-Inoculation (hours)

0.25 0.5 1 4 24 120 168 4 24 168

2000 / 400 4 4 3 0 0 0 0 4 1 0

1000 / 200 4 4 4 0 0 0 0 4 3 1

500 / 100 4 4 4 1 0 0 0 4 4 1

250 / 50 4 4 4 2 0 0 0 4 4 4

125 / 25 4 4 4 4 0 0 0 4 4 4

0 4 4 4 4 4 4 4 4 4 4

12% DBMAL product (ppm) / DBMAL (ppm a.i.)

24

hr.

Pre

-In

ocu

lati

on


Re-

Ino

cula

tio

n


0.25 0.5 1 4 24 120 168 4 24 168

5000 / 600 4 4 4 4 0 0 0 4 0 0

3333 / 400 4 4 4 3 0 0 0 4 1 1

1666 / 200 4 4 4 4 0 0 0 4 2 1

833 / 100 4 4 4 4 0 0 0 4 2 1

417 / 50 4 4 4 4 1 0 1 4 4 4

280 / 33.6 4 4 4 4 4 4 4 4 4 4

0 4 4 4 4 4 4 4 4 4 4

1.5% CMIT/MIT product (ppm) / CMIT/MIT (ppm a.i.)

24

hr.

Pre

-In

ocu

lati

on


Re-

Ino

cula

tio

n Time Post Re-

Inoculation (hours)

0.25 0.5 1 4 24 120 168 4 24 168

1675 / 22.5 4 4 4 4 3 0 0 4 3 0

0 4 4 4 4 4 4 4 4 4 4

10% MBIT/CMIT/MIT product (ppm) / MBIT/CMIT/MIT (ppm

a.i.)

24

hr.

Pre

-In

ocu

lati

on Time Post Biocide Addition (hours)

Re-

Ino

cula

tio

n


0.25 0.5 1 4 24 120 168 4 24 168

3700 / 370 4 4 4 4 1 0 0 4 0 0

1850 / 185 4 4 4 4 0 0 0 4 2 0

0 4 4 4 4 4 4 4 4 4 4

Float Solution



in 1-4 hours after the first

challenge.

DBMAL was fast (24 hours)

and provided long-term

efficacy.

CMIT/MIT was slow, but

provided long-term efficacy.

MBIT/CMIT/MIT combo


in 24 hours and provided

long-term protection.

20% DBNPA product (ppm)/ DBNPA (ppm a.i.)

24

hr.

Pre

-In

ocu

lati

on


Re-

Ino

cula

tio

n

Time post Re-Inoculation (hours)

0.25 0.5 1 4 24 120 168 4 24 168

2000 / 400 4 4 0 0 0 0 0 0 0 0

1000 / 200 4 4 3 0 0 0 0 0 1 0

500 / 100 4 4 4 0 0 0 0 4 0 0

250 / 50 4 4 4 0 0 0 0 4 4 4

125 / 25 4 4 4 0 0 0 0 4 4 4

0 4 4 4 4 4 4 4 4 4 4

12% DBMAL product (ppm) / DBMAL (ppm a.i.)

24

hr.

Pre

-In

ocu

lati

on


Re-

Ino

cula

tio

n


0.25 0.5 1 4 24 120 168 4 24 168

5000 / 600 4 4 4 4 0 0 0 4 0 0

3333 / 400 4 4 4 4 0 0 0 4 0 0

1666 / 200 4 4 4 4 0 0 0 4 0 0

833 / 100 4 4 4 4 0 0 0 4 0 0

417 / 50 4 4 4 4 0 0 0 4 1 1

280 / 33.6 4 4 4 4 1 1 1 4 2 4

0 4 4 4 4 4 4 4 4 4 4

1.5% CMIT/MIT product (ppm) / CMIT/MIT (ppm a.i.)

24

hr.

Pre

-In

ocu

lati

on


Re-

Ino

cula

tio

n Time post Re-

Inoculation (hours)

0.25 0.5 1 4 24 120 168 4 24 168

1675 / 22.5 4 4 4 4 3 0 0 4 2 0

0 4 4 4 4 4 4 4 4 4 4

10% MBIT/CMIT/MIT product (ppm) / MBIT/CMIT/MIT (ppm

a.i.)

24

hr.

Pre

-In

ocu

lati

on


Re-

Ino

cula

tio

n


0.25 0.5 1 4 24 120 168 4 24 168

3700 / 370 4 4 4 4 0 0 0 4 0 0

1850 / 185 4 4 4 4 0 0 0 4 0 0

0 4 4 4 4 4 4 4 4 4 4

Performance Trends


21

DBMAL

DBNPA

CMIT/MIT

Speed Endurance

MBIT/CMIT/MIT

Rapid Kill Long-term

Preservation

An In-Depth Look at Paint

Preservation with the

MBIT/CMIT/MIT

Combination


22

23

High-Throughput

Challenge Evaluations

Validated to standard agar plate tests Generate large amounts of comparative performance data

Quickly evaluate combinations for synergy or antagonism

Important for biocide optimization studies as VOC content becomes lower In-can preservative plus co-biocide

Compare lab strains vs. manufacturing facility contaminants


More than 13,000 data points on

biocidal actives,

concentrations, or active ratios

High-Throughput Screening –

A Day’s Work

vs.

Limited number

of data points 24


Performance in Paint Sample pH 8.52

Against Bacteria

25

Day 1 Day 2 Day 1 Day 4 Day 1 Day 6 Day 1 Day 6 Day 13

4000 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

3077 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1.5

2367 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 2.5

1821 0.0 0.0 0.0 0.0 0.0 0.0 0.0 3.5 8.0

1401 0.0 0.0 0.0 0.0 0.0 2.5 5.5 8.0 6.5

1077 0.0 0.0 0.0 0.0 0.0 7.0 8.0 7.0 7.0

829 0.0 0.0 0.0 0.0 0.5 8.0 7.5 7.5 6.5

637 0.0 0.0 0.0 0.0 3.0 8.0 7.0 6.5 6.5

0 0.0 0.0 0.0 0.0 7.2 7.6 7.2 7.1 6.7

BIOBAN 557

(ppm)

Cycle I

Ch

alle

nge

1 (

5 x

106

CFU

/ml)

Ch

alle

nge

2 (

5 x

106

CFU

/ml)

Cycle IV

Ch

alle

nge

3 (

5 x

106

CFU

/ml)

Cycle IIICycle II

Ch

alle

nge

4 (

5 x

106

CFU

/ml)


2500 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

1923 0.0 0.0 0.0 0.0 0.0 7.5 7.5 7.0 7.0

1479 0.0 0.0 0.0 0.0 3.5 7.5 7.5 6.5 6.5

1138 0.0 0.0 0.0 0.0 4.0 6.0 7.0 7.0 6.5

875 0.0 0.0 0.0 0.0 6.0 7.5 7.0 7.0 7.0

673 0.0 0.0 0.0 0.0 6.0 7.0 7.0 7.0 7.0

518 0.0 0.0 0.0 0.0 6.5 7.0 7.0 7.0 7.5

398 0.0 0.0 0.0 0.0 7.0 7.0 6.0 7.0 6.0

0 0.0 0.0 0.0 0.0 7.2 7.6 7.2 7.1 6.7

Cycle IIICycle IICycle IC

hal

len

ge 2

(5

x 1

06 C

FU/m

l)

Ch

alle

nge

1 (

5 x

106

CFU

/ml)

Ch

alle

nge

4 (

5 x

106

CFU

/ml)

ROCIMA BT 2S

(ppm)

Cycle IV

Ch

alle

nge

3 (

5 x

106

CFU

/ml)


1675 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

1288 0.0 0.0 0.0 0.0 0.0 0.0 0.5 4.0 5.0

991 0.0 0.0 0.0 0.0 0.0 0.0 5.0 6.5 7.5

762 0.0 0.0 0.0 0.0 0.0 2.5 7.5 8.0 7.0

586 0.0 0.0 0.0 0.0 0.0 1.5 7.5 7.5 7.0

451 0.0 0.0 0.0 0.0 0.5 6.0 7.0 8.0 7.0

347 0.0 0.0 0.0 0.0 1.0 7.5 7.5 7.5 7.5

267 0.0 0.0 0.0 0.0 5.0 7.0 7.0 7.5 6.5

0 0.0 0.0 0.0 0.0 7.2 7.6 7.2 7.1 6.7

Ch

alle

nge

4 (

5 x

106

CFU

/ml)

Cycle IVKATHON LX 1.5%

(ppm)

Ch

alle

nge

1 (

5 x

106

CFU

/ml)

Cycle I

Ch

alle

nge

2 (

5 x

106

CFU

/ml)

Cycle II Cycle III

Ch

alle

nge

3 (

5 x

106

CFU

/ml)

Passing at 2367 ppm product;

213 ppm MBIT

11.8 ppm CMIT,

11.8 ppm MIT

(23.6 ppm total CMIT/MIT)


475 ppm BIT (EPA max)


25 ppm CMIT/MIT (EPA max)


10%

MBIT/CMIT/MIT

Product (ppm)

19% BIT Product

(ppm)

1.5% CMIT/MIT

Product

(ppm)

No margin of error with

industrial hygiene.

No margin of error with

industrial hygiene.

Passing with a

comfortable margin.

Paint pH 9.03 Against Customer-

Specific Yeast and Standard Mold

DOW CONFIDENTIAL- Do not share without permission

26

19% BIT Product (ppm) / BIT (ppm a.i.)

Ch

alle

nge

1

(5

x 1

06 CFU

/ml)

Cycle I

Ch

alle

nge

2

(5

x 1

06 CFU

/ml)

Cycle II

Ch

alle

nge

3

(5

x 1

06 CFU

/ml)

Cycle III

Day 1

Day 7

Day 1

Day 8

Day 1

Day 6

2000 / 380 4 2 4 0 4 2

1250 / 237.5 4 2 4 2 4 2

500 / 95 4 4 4 2 4 4

0 4 4 4 4 4 4

10% MBIT/CMIT/MIT Product (ppm) / MBIT/CMIT/MIT

(ppm a.i.)

Ch

alle

nge

1

(5

x 1

06 C

FU/m

l)

Cycle I

Ch

alle

nge

2

(5

x 1

06 C

FU/m

l)

Cycle II

Ch

alle

nge

3

(5

x 1

06 C

FU/m

l)

Cycle III

Day 1

Day 7

Day 1

Day 8

Day 1

Day 6

3700 / 370 0 0 0 0 0 1

2700 / 270 0 0 1 0 0 0

1800 / 180 0 1 1 0 0 0

900 / 90 0 1 1 1 0 1

0 4 4 4 4 4 4

1.5% CMIT/MIT Product (ppm) / CMIT/MIT (ppm a.i.)

+ 95 ppm BIT

Ch

alle

nge

1

(5

x 1

06 CFU

/ml)

Cycle I

Ch

alle

nge

2

(5

x 1

06 CFU

/ml)

Cycle II C

hal

len

ge 3

(5 x

106 C

FU/m

l)

Cycle III

Day 1

Day 7

Day 1

Day 8

Day 1

Day 6

1675 0 0 4 2 4 4

1200 0 0 4 2 4 4

900 0 0 4 2 4 4

600 0 0 4 2 4 4

0 4 4 4 4 4 4

81 ppm MBIT

9 ppm CMIT/MIT

90 ppm total

380 ppm BIT

25 ppm CMIT/MIT

95 ppm BIT

120 ppm total

Passed

Failed

Failed

Summary (1 of 2)

Paints today are more susceptible to microbial contamination due to

more sustainable ingredients, lower VOC levels, and increased

water content.

Preservative choices are limited due to global registration status,

compatibility with final products and raw materials, and antimicrobial

efficacy spectra.

Product quality is critical for manufacturers and consumers.

Rapid-kill antimicrobials (ex. DBNPA) ≠ long-term preservatives.

Rapid-kill biocidal actives are important for reducing stress on the

long-term preservatives.


27

Summary (2 of 2)

Two novel biocidal actives were evaluated:

MBIT and DBMAL.

MBIT displayed improved efficacy over BIT.

However, DBNPA is faster than DBMAL.

The combination of MBIT/CMIT/MIT provided rapid-kill and long-

term preservation in paint, wash water, and a float solution.

MBIT/CMIT/MIT was effective against bacteria, as well as fungi

(yeast and mold). Yeast contamination is increasingly becoming an

issue for paint formulations.


28

DOW CONFIDENTIAL- Do not share without permission

29

Notice: No freedom from infringement of any patent owned by Dow or

others is to be inferred. Because use conditions and applicable laws may

differ from one location to another and may change with time, Customer is

responsible for determining whether products and the information in this

document are appropriate for Customer's use and for ensuring that

Customer's workplace and disposal practices are in compliance with

applicable laws and other government enactments. The product shown in

this literature may not be available for sale and/or available in all

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