Title of Invention

A BASE FORMULATION USEFUL FOR PREPARATION OF SEMIGLOSS ENAMELS

Abstract The present invention provides a base formulation useful for preparation of semigloss emamels comprising 18 to 22 weight % of fly ash powder, 2 to 6 weight % of pigments , 1% by weight of antisettling agents , 35 weight % of resin selected from Bisphenol - A epichlorohydrin epoxy resin and 20 weight % of organic solvents , to obtain a smooth paste having pigment volume concentration in the range of 23.63 to 25.67.
Full Text The present invention relates to a novel base formuation useful for preparation of semigloss enamels.
The significance of the present invention is development of new formulations of semigloss enamels based on waste materials. The new formulations based on fly ash can be applied to a variety of surfaces for decorative purpose which simultaneously provides protection to the surface by acting as a barrier. The enamel formulations can also be applied as second coat over primers where higher degree of protection is desirable. The dulling of gloss is less in case of fly ash enamels as compared to the formulations based on conventional mineral extenders. The other properties of fly ash that offer added advantage as extender are its chemical inertness, abrasive nature, less oil absorption and low specific gravity values. Fly ash can be usod without any chemical upgradation. The processing of fly ash is simple unlike other mineral extenders, which require long processing involving crushing, grinding, levigation etc. to bring the ores to the final forms.
Reference may be made to published paper by B.B. Gogte & Alok Agrawal in Paint India, Oct.1994, XLIV,(10), 51-56, entitled 'Fly ash based coatings' wherein work has been reported on preparation of semigloss enamels incorporating fly ash as extender. The formulations were developed as water thinnable alkyd emulsion systems. The enamels were formulated in two shades as grey and green. The formulations of grey enamels are as mentioned below:

(Table Removed)

The formulations of green enamels formulated as water thinnable alkyd systems are as below:

(Table Removed)
The drawbacks are inferior durability and gloss characteristics of the formulations. The present invention describes the formulation of organic solvent-based semigloss enamels incorporating fly ash as extender for decorative applications. The influence of fly ash on performance properties of the enamels as gloss and colour shades have been studied.
The development of enamel formulations useful for decorative application is a new area of flyash utilization leading to partial replacement of conventional extenders, simultaneously giving solution to safe disposal of an industrial waste.
The main object of the present invention is to provide a base formulation useful for preparation of semigloss enamel formulation useful for decorative applications, which obviates the drawbacks as detailed above.
Another object of the present invention is to provide a base formulation wherein fly ash, an industrial waste product, has been used.

Accordingly the present invention provides a base formulation useful for preparation of semigloss emamels which comprises: 18 to 22 weight % of fly ash powder, 2 to 6 weight % of pigments as defined herein , 1% by weight of antisettling agents as described here in, 35 weight % of resin selected from Bisphenol - A epichlorohydrin epoxy resin and 20 weight % of organic solvents as described herein , to obtain a smooth paste having pigment volume concentration in the range of 23.63 to 25.67.
In another embodiment of the present invention, the pigments used may be such as titanium
dioxide, pthalocyanine blue, lemon chrome or mixtures thereof, having particle size less than 30
microns.
In still another embodiment of the present invention the antisettling agent used may be such as
fine silica, aluminium stearate or soya lecithin.
In yet another embodiment of the present invention, the organic solvent used may be such as
xylene, toluene, N-bytyl alcohol or mixtures thereof.
The improved process of the present invention involves washing, drying and sieving of ESP
(electrostatic precipitators) fly ash to less than 38 microns. The enamel compositions are
formulated by adjusting PVC. The pigments used are like titanium dioxide, pthalocyanine blue
and lemon chrome which are sieved to a particle size of less than 38 micros. Fine silica is
added as an antisettling agent. Resin used is Bisphenol - A epichlorohydrin epoxy with xylene
and N-butyl alcohol as solvents. Modified polymidoamine is added as curing agent to the
prepared base. The preparation is done by mixing resin and solvent as per the formulation with
other powdered ingredients to form mill base of paste consistency, which is then fed in a ball
mill with steel balls for grinding. The dispersion process is continued till the desired particle
size ( 6-7 microns) is obtained on Hegmans Gauge. The viscosity and specific gravity for the
formulations are determined. Film properties of the enamels are examined by application on
mild steel (m.s.)

panels. Immersion tests are conducted in distilled water, 5% Na2C03, 2% H2SO4, 1% NaOH and organic solvents like toluene and mineral sprit for determination of corrosion resistance. The damage to the enamel coat if any, like blistering, chalking, checking, cracking etc. e visually observed. High stress (two body) abrasion test is conducted. Samples are exposed to natural weathering t 45 facing south and visual observations are taken at regular intervals.
The results indicate good appearance and brushability characteristics of fly ash enamels. The gloss values obtained are in the range of 52-56%. The blue and pale yellow shades were unaffected by whitish grey colour of the ash, obviously a variety of colour shades can be obtained in fly ash enamels but very light shades as white may be slightly affected by the greyish colour of the ash. The maximum scratch hardness of the formulations is 1600 gms which is higher as compared to that of the enamels based on water thinnable systems i e 1000 gms. The presence of abrasive materials like silica and alumina as major constituents in fiy ash helps to increase the abrasive wear property of the formulations in which it is incorporated. The chemical inertness of fly ash imparts excellent corrosion resistance to enamels in acidic and basic solutions as also in organic solvents. The present study revealed the properties of fly ash, which contribute to its superiority as extender are its less oil absorption and low specific gravity values. Less oil absorption helps to reduce the amount of resin required without affecting the performance of the formulations. The smooth surface structure of fly ash is responsible for less oil absorption. The low specific gravity of fly ash is an added advantage, as incorporating higher amount of fly ash does not have any adverse increase in the bulk density of the formulation. As observed solvent borne enamel formulations based on fly ash have better gloss, mechanical properties and corrosion resistance than similar compositions based on water thinnable systems.

The following examples are given by way of illustration of the present invention and should not be construed to limit the scope of the present invention.
EXAMPLE - 1
18% weight % of prewashed and dried fly ash sieved to particle size less than38 microns, pigments 4.5 weight % of titanium dioxide and 1.5 weight % of pthallocyanine blue sieved to particle size less than38 microns is mixed with 1 weight % of fine silica, 35 weight % of Bisphenol-A epichlorohydrin epoxy resin, 15 weight % of xylene and 5 weight % of N-butyl alcohol to obtain a smooth paste having pigment volume concentration of 24.87%. The paste is grinded and dispersed in a laboratory ball mill till be particle size is in the range of 6 to? microns to obtain the enamel base.
4 parts by weight of enamel base is mixed with 1 part by weight of modified polyamidoamine curing agent. After giving proper time for curing, as 5 to 10 minute, the semigloss enamel is applied by brush or spraying.
EXAMPLE - 2
20 weight % of prewashed and dried fly ash sieved to particle size less than38 microns, pigments 2.5 weight % of titanium dioxide and 1.5 weight % of pthallocyanine blue sieved to particle size less than38 microns is mixed with 1 weight % of fine silica, 35 weight % of Bisphenol - A epichlorohydrin epoxy resin, 15 weight % of xylene and 5 weight % of N- butyl alcohol to obtain a smooth paste having pigment volume concentration of 25.59%. The paste is grinded and dispersed in a laboratory ball mill till the particle size is in the range of 6 to 7 microns to obtain the enamel base.
4 parts by weight of enamel base is mixed with 1 part by weight of modified polyamidoamine curing agent. After giving proper time for curing, as 5 to 10 minute, the semigloss enamel is applied by brush or spraying.

EXAMPLE - 3
22 weight % of prewashed and dried fly ash sieved to particle size less than38 microns, pigments like 1.5 weight % of titanium dioxide and 0.5 weight % of pthallocyanine blue sieved to particle size less than38 microns is mixed with 1 weight % of fine silica, 35 weight % of Bisphenol-A epichlorohydrin epoxy resin, 15 weight % of xylene and 5 weight % of N-butyl alcohol to obtain a smooth paste having pigment volume concentration of 25.67%. The paste is grinded and dispersed in a laboratory ball mill till the particle size is in the range of 6 to 7 microns to obtain the enamel base. 4 parts by weight of enamel base is mixed with 1 part by weight of modified polyamidoamine curing agent. After giving proper time for curing, as 5 to 10 minute, the semigloss enamel is applied by brush or spraying.
EXAMPLE - 4
18 weight % of prewashed and dried fly ash sieved to particle size less than38 microns, pigments like 4.5 weight % of titanium dioxide and 1.5 weight % of lemon chrome sieved to particle size less than38 microns is mixed with 1 weight % of fine silica, 35 weight % of Bisphenol-A epichlorohydrin epoxy resin, 15 weight % of xylene 5 weight % of N-butyl alcohol to obtain a smooth paste having pigment volume concentration of 23.63%. The paste is grinded and dispersed in a laboratory ball mill till the particle size is in the range of 6 to 7 microns to obtain the enamel base.. 4 parts by weight of enamel base is mixed with 1 part by weight of modified polyamidoamine curing agent. After giving proper time for curing, as 5 to 10 minute, the semigloss enamel is applied by brush or spraying.
EXAMPLE - 5
20 weight % of pre washed and dried flyash sieved to particle size less than 38 microns pigments2.5 weight % of titanium dioxide and 1.5 weight % of lemon chrome sieved to particle size less than 38 microns is mixed with 1 weight % of fine silica, 35% of Bisphenol - A epichlorohydrin epoxy resin, 15 weight % of xylene and weight of N - butyl alcohol to obtain a smooth paste having pigment volume concentration of 24.37 %. The paste is

grinded and dispersed in laboratory ball mill till the particle size is in the range of6 to 7 microns to obtain the enamel base.
4 parts by weight of enamel base is mixed with 1 part by weight of modified polyamidoamine curing agent. After giving proper time for curing, as 5 to 10 minute, the semigloss enamel is applied by brush or spraying.
EXAMPLE - 6
22 weight % of prewashed and dried flyash sieved to particle size less than 30 microns pigment 1.5% of titanium dioxide and 0.5 weight % of lemon chrome sieved to particle size less than 38 microns is mixed with 1 weight % of fine silica, 35 weight % of Bisphenol -A -epichlorohydri n epoxy resin, 1 5 weight % of xylene and 5 weight % of N- butyl alcohol to obtain a smooth having pigment volume concentration of 25.27 %. The paste is grinded and dispersed in laboratory ball mill till the particle size is in the range of 6 to 7 microns to obtain the enamel base.
4 parts by weight of enamel base is mixed with 1 part by weight of modified polyamidoamine curing agent. After giving proper time for curing, as 5 to 10 minute, the semigloss enamel is applied by brush or spraying.
As mentioned in above examples, semi gloss enamel formulations based on fly ash have good appearance, drying time, film thickness and brushability. They have improved mechanical properties (like scratch hardness, abrasion resistance) and corrosion resistance in water, chemicals and organic solvents. In natural weathering test a slight dullness in gloss and colour fading was observed in pale yellow enamel whereas the colour and gloss of blue enamel was unaffected. The formulations during storage. Overall, the performance of solvent based enamels incorporating fly ash was improved in terms of appearance, mechanical properties and durability characteristics as compared to the water thinnable systems. The physical properties and film characteristics of the developed formulations are mentioned in the table below:

(Table Removed)
P : Passes 12lbs./12"
The formulations prepared are not mere admixture resulting in mere aggregation of the properties of individual ingredients but is a synergistic
mixture hence the properties of base formulations are different from the individual components.
The main advantages of the present invention are
1. Technically viable semi gloss enamel formulations based on cost effective
materials.
2. New enamel formulations based on flyash offer good appearance,
brushability and gloss values.
3. Flyash based enamels offer better resistance to chemicals and organic
solvents as compared to similar formulations based on water thinnable
systems.
4. Flyash enamels have improved mechanical properties as scratch hardness
and abrasive wear resistance.
5. No adverse effect has been observed on drying time and film thickness of
enamels by incorporating flyash.
6. No hard settling occurs during storage in flyash enamels
7. Utilization of flyash in improved formulations will help in safe disposal of
an industrial waste.







We Claim:
1. A base formulation useful for preparation of semigloss emamels which
comprises: 18 to 22 weight % of fly ash powder, 2 to 6 weight % of pigments
as defined herein , 1% by weight of antisettling agents as described here in,
35 weight % of resin selected from Bisphenol - A epichlorohydrin epoxy
resin and 20 weight % of organic solvents as described herein , to obtain a
smooth paste having pigment volume concentration in the range of 23.63 to
25.67.
2. A base formulation as claimed in claim 1 wherein fly ash powder of particle
size less than 38 microns.
3. A base formulation as claimed in 1 and 2 wherein the pigments used is
selected from titanium oxide, pthallocyanine blue, lemon chrome or mixtures
thereof, having particle size less than 38 micron.
4. A base formulation as claimed in claim 1-3 wherein the antisettling agent
used is selected from fine silica, aluminium stearate or Soya lecithin.
5. A base formulation as claimed in claims 1-4 wherein organic solvent used is
selected from xylene, toluene, N-butyl alcohol of mixtures thereof.
6. A base formulation useful for preparation of semigloss enamels substantially
as herein described with reference to the examples.

Documents:

964-del-2001-abstract.pdf

964-del-2001-claims.pdf

964-del-2001-correspondence-others.pdf

964-del-2001-correspondence-po.pdf

964-del-2001-description (complete).pdf

964-del-2001-form-1.pdf

964-del-2001-form-18.pdf

964-del-2001-form-2.pdf

964-del-2001-form-3.pdf


Patent Number 242401
Indian Patent Application Number 964/DEL/2001
PG Journal Number 35/2010
Publication Date 27-Aug-2010
Grant Date 25-Aug-2010
Date of Filing 19-Sep-2001
Name of Patentee COUNCIL OF SCIENTIFIC AND INDUSTRIAL RESEARCH
Applicant Address RAFI MARG, NEW DELHI-110001
Inventors:
# Inventor's Name Inventor's Address
1 SANGEETA TIWARI REGIONAL RESEARCH LABORATORY, BHOPAL, 462026, M.P., INDIA
2 MOHINI SSAXENA REGIONAL RESEARCH LABORATORY, BHOPAL, 462026, M.P., INDIA
PCT International Classification Number B32B 13/12
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA