Title of Invention	"A PROCESS FOR THE PREPARATION OF A NOVEL SEMIGLOSS ENAMEL FORMULATION USEFUL FOR DECORATIVE APPLICATIONS"
Abstract	The invention relates to a process for preparation of novel semi gloss enamel formulation useful for decorative applications. 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 process steps are:mixing fly ash powder, pigments, antisettling agents, resin Bisphenol -A epichlorohydrin epoxy resin and organic solvents, to obtain a smooth paste grinding and dispersing the paste obtained as above till the particle size is in the range of 6-7 microns to obtain a semigloss enamel base; mixing 4 parts by weight of semigloss enamel base so obtained with 1 part by weight of curing agent modified polyamidoamines optionally with requisite amount of organic solvent to obtain the said formulation.

Title of Invention

"A PROCESS FOR THE PREPARATION OF A NOVEL SEMIGLOSS ENAMEL FORMULATION USEFUL FOR DECORATIVE APPLICATIONS"

Abstract

The invention relates to a process for preparation of novel semi gloss enamel formulation useful for decorative applications. 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 process steps are:mixing fly ash powder, pigments, antisettling agents, resin Bisphenol -A epichlorohydrin epoxy resin and organic solvents, to obtain a smooth paste grinding and dispersing the paste obtained as above till the particle size is in the range of 6-7 microns to obtain a semigloss enamel base; mixing 4 parts by weight of semigloss enamel base so obtained with 1 part by weight of curing agent modified polyamidoamines optionally with requisite amount of organic solvent to obtain the said formulation.

Full Text	The present invention relates to a process for preparation of a novel semigloss enamel formulation useful for decorative applications. 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 used 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) 1. The formulations of green enamels formulated as water thinnabie 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 process for preparation of novel semigloss enamel formulation useful for decorative applications, which obviates the drawbacks as detailed above. Another object of the present invention is to provide a process wherein fly ash, an industrial waste product, has been used. Accordingly the present invention provides a process for preparation of novel semi gloss enamel formulation useful for decorative applications which comprises: i. Characterized in that by mixing 18 to 22 weight % of fly ash powder, 2 to 6 weight % pigments, 1% by weight of antisettling agents, 35 weight% of resin Bisphenol -A epichlorohydrin epoxy resin and 20 weight% of organic solvents, to obtain a smooth paste having pigment value concentration in the range of 23.63 to 25.67%; ii. grinding and dispersing the paste obtained in step (i) till the particle size is in the range of 6-7 microns to obtain a semigloss enamel base; iii. mixing 4 parts by weight of semigloss enamel base as obtained in step (ii) with 1 part by weight of curing agent modified polyamidoamines optionally with requisite amount of organic solvent to obtain the said formulation. In an embodiment of the present invention the fly ash powder used may be of particle size less than 38 microns. 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, aluminum stearate or soya lecithin. In yet another embodiment of the present invention, the organic solvent used may be such as xylene, toluene, N-butyl alcohol or mixtures thereof. In our copending patent application no nf 143/98, we have claimed and disclosed a novel base formulation which has been used for the preparation of semigloss formulation. The improved process of the present invention involves washing, drying and sieving of ESP (electro static 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 than38 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% H2S04, 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 fly 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 minutes, 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 7 minutes, 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 6 minutes, 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 10 minutes, 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 foe curing as 10 minutes the semi gloss 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 -epichlo rohydrin epoxy resin, 15 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 f modified polyamidoamine curing agent. After giving proper time foe curing, as 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. No hard setting occurs in 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) 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 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 process for preparation of novel semi gloss enamel formulation useful for decorative applications which comprises: 1. Characterized in that by mixing 18 to 22 weight % of fly ash powder, 2 to 6 weight % pigments, 1% by weight of antisettling agents, 35 weight% of resin Bisphenol -A epichlorohydrin epoxy resin and 20 weight % of organic solvents to obtain a smooth paste having pigment value concentration in the range of 23.63 to 25.67%; ii. grinding and dispersing the paste obtained in step (i) till the particle size is in the range of 6-7 microns to obtain a semigloss enamel base; iii. mixing 4 parts by weight of semigloss enamel base as obtained in step (ii) with 1 part by weight of curing agent modified polyamidoamines optionally with requisite amount of organic solvent to obtain the said formulation. 2. A process as claimed in claim 1 wherein fly ash powder of particle size less than 38 microns is used. 3. A process as claimed in claims 1 & 2 wherein the pigments such as titanium oxide, pthallocyanine blue, lemon chrome or mixtures thereof, having particle size less than 38 micron is used. 4. A process as claimed in claims 1-3 wherein the antisettling agent used is selected from fine silica, aluminium stearate or soya lecithin. 5. A process as claimed in claims 1-4 wherein organic solvent used is selected from xylene, toluene, N-butyl alcohol or mixtures thereof. 6. A process for preparation of novel semigloss enamel formulation useful for decorative applications substantially as herein described with reference to the examples.

Full Text

The present invention relates to a process for preparation of a novel semigloss enamel formulation useful for decorative applications.
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 used 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)
1. The formulations of green enamels formulated as water thinnabie 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 process for preparation of novel semigloss enamel formulation useful for decorative applications, which obviates the drawbacks as detailed above.
Another object of the present invention is to provide a process wherein fly ash, an industrial waste product, has been used.

Accordingly the present invention provides a process for preparation of novel semi gloss enamel formulation useful for decorative applications which comprises:
i. Characterized in that by mixing 18 to 22 weight % of fly ash powder, 2 to 6
weight % pigments, 1% by weight of antisettling agents, 35 weight% of resin Bisphenol -A epichlorohydrin epoxy resin and 20 weight% of organic solvents, to obtain a smooth paste having pigment value concentration in the range of 23.63 to 25.67%;
ii. grinding and dispersing the paste obtained in step (i) till the particle size is in the range of 6-7 microns to obtain a semigloss enamel base;
iii. mixing 4 parts by weight of semigloss enamel base as obtained in step (ii) with 1 part by weight of curing agent modified polyamidoamines optionally with requisite amount of organic solvent to obtain the said formulation.
In an embodiment of the present invention the fly ash powder used may be of particle size less than 38 microns.
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, aluminum stearate or soya lecithin.
In yet another embodiment of the present invention, the organic solvent used may be such as xylene, toluene, N-butyl alcohol or mixtures thereof.
In our copending patent application no nf 143/98, we have claimed and disclosed a novel base formulation which has been used for the preparation of semigloss formulation.
The improved process of the present invention involves washing, drying and sieving of ESP (electro static 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 than38 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% H2S04, 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 fly 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 minutes, 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 7 minutes, 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 6 minutes, 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 10 minutes, 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 foe curing as 10 minutes the semi gloss 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 -epichlo rohydrin epoxy resin, 15 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 f modified polyamidoamine curing agent. After giving proper time foe curing, as 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. No hard setting occurs in 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)
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 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 process for preparation of novel semi gloss enamel formulation useful for decorative applications which comprises:
1. Characterized in that by mixing 18 to 22 weight % of fly ash powder, 2 to 6
weight % pigments, 1% by weight of antisettling agents, 35 weight% of resin
Bisphenol -A epichlorohydrin epoxy resin and 20 weight % of organic
solvents to obtain a smooth paste having pigment value concentration in the
range of 23.63 to 25.67%;
ii. grinding and dispersing the paste obtained in step (i) till the particle size is in the range of 6-7 microns to obtain a semigloss enamel base;
iii. mixing 4 parts by weight of semigloss enamel base as obtained in step (ii) with 1 part by weight of curing agent modified polyamidoamines optionally with requisite amount of organic solvent to obtain the said formulation.
2. A process as claimed in claim 1 wherein fly ash powder of particle size less than
38 microns is used.
3. A process as claimed in claims 1 & 2 wherein the pigments such as titanium
oxide, pthallocyanine blue, lemon chrome or mixtures thereof, having particle
size less than 38 micron is used.
4. A process as claimed in claims 1-3 wherein the antisettling agent used is
selected from fine silica, aluminium stearate or soya lecithin.
5. A process as claimed in claims 1-4 wherein organic solvent used is selected from
xylene, toluene, N-butyl alcohol or mixtures thereof.
6. A process for preparation of novel semigloss enamel formulation useful for
decorative applications substantially as herein described with reference to the
examples.

Documents:

963-del-2001-abstract.pdf

963-del-2001-claims.pdf

963-del-2001-correspondence-others.pdf

963-del-2001-correspondence-po.pdf

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

963-del-2001-form-1.pdf

963-del-2001-form-18.pdf

963-del-2001-form-2.pdf

963-del-2001-form-3.pdf

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Patent Number

220682

Indian Patent Application Number

963/DEL/2001

PG Journal Number

30/2008

Publication Date

25-Jul-2008

Grant Date

02-Jun-2008

Date of Filing

19-Sep-2001

Name of Patentee

COUNCIL OF SCIENTIFIC AND INDUSTRIAL RESEARCH

Applicant Address

Inventors:

#	Inventor's Name	Inventor's Address
1	SANGEETA TIWARI
2	MOHINI SAXENA

PCT International Classification Number

C09D 1/00

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA