Lime dispersion-paint and process for its manufacture

The present intent concerns a process for the preparation of a lime-ink dispersion in aqueous medium.

There is a commercially available lime-containing aqueous paint due to the very poor storage stability of aqueous mixtures containing lime.

The Applicant's aim was to discover a paint ie lime in storage stable aqueous medium and ultraviolet rays and also filled with good filmogeneity.

The aqueous lime dispersion paint which is the object of the present invention is a composition based on a binder, pulverulent materials and dispersion aqueous paint adjuvants, and said composition characterized by:

- the binder is comprised of an alkyl acrylate filmogenic copolymer and a nonionogenic ethylenic monomer dispersing within a stable aqueous medium with basic rR, said nonionic ethylene monomer being such a good polymer corresponding to said monomer non-ionic ethylenic acid has a glass transition point of 70

170 ° C if the verulent substances contain, in addition to one or more pigments, extinct airborne lime with a low hydroxicity index;

- that adjuvants are chosen from among those which are

<img file="PT78025B_D0001.tif" />

they are basic pK, and comprise, among others, a stabilizing agent consisting of L-sortitol.

ink-dispersion means a dispersion having a fluid consistency and also a iso-dispersion having a pasty or semi-fluid consistency, for example a coating.

Second ε ^rorraa ΑΓ'ΌΕ 1 3C-CO1, powdery substances are solid substances, insoluble in the medium ie suspension, finely divided and dispersed in this medium and after wetting '¹. ^Ηο In the present case, the powdery substances consist of pigment or pigments and lime for a fluid dispersion, and in addition, fillers such as carbonates, with a semi-fluid or pasty dispersion.

Still according to ^HA7 standard^!'CR 1 10-001', are adjuvants, 'substances which may be incorporated in small quantities into binders, varnishes, paints and, where appropriate, coatings to develop certain qualities appropriate for improving both the conditions of manufacture and / or conservation and / or application, whether certain specific properties:

^TIn the present case, adjuvants are, among others, dispersants, thickeners, stabilizers, antifoam, antifreeze, coalescence, fungicides, etc.

The filmogenic copolymer that enters the binder composition is obtained from an alkyl acrylate and a nonionic ethylene monomer.

Non-ionogenic ethylenic monomers include inilaromatic monomers such as esyrene, methylstyrenes, vinyl toluenes; alkyl methacrylates, for example methyl methacrylate; acrylonitrile.

<img file="PT78025B_D0002.tif" />

The

Alkyl acrylates which may be used are those whose corresponding homopolymer has a transition point. ^T,area between + 10 ° C and -6 ° C.

These include alkyl acrylates whose alkyl alkyl contains 1 to 4 carbon atoms and preferably 1 to 4 carbon atoms.

The respective amounts of non-ionogenic ethyl monomer and alkyl acrylate to be used are chosen such that the obtained copolymer has a glass transition point of -> + 2 ° C.

The amounts of monomers are s. use depends on the nature of said comonomers and on the transition temperature of the desired conolymer. Said amounts can be readily determined by applying, for example, the formula of ΣΌΣ indicated in Bull, An. Hys, Soc. 15, 6, 1, 123. Thus:

an ethyl styrene-televylate copolymer has a glass transition tale ranging from 0 ° C to 20 ° C when the styrene / ethyl acrylate ratio ranges from 26/74 to 4p / 5p;

The styrene-stilylate and propyl copolymer has an Î ± -treat transition point ranging from CÂ ° to 2Â ° C when the styrene / propyl acrylate ratio is_slaugh_& from 36/64 to> 2/43;

polystyrene having a glass transition point of + 110 ° C, ethyl polyacrylate of -24 ° C and propyl polyacrylate of -37 ° C.

The values ​​of the indicated ion transition points are those measured by the method called Differential scanning calorimetrv, described for example by A. Lambert in Folymer 10_? 319,1969.

ll

Aqueous dispersions of nonionogenic ethylene monomer and alkyl acrylate copolymers are obtained by aqueous emulsion polymerization of said monomers, and then mixed with a stabilizing monomer in a stable medium with alkaline pu.

said polymerization means comprises, in addition to said monomers, an aqueous phase and various classic adjuvants. emulsion polymerization products (catalysts, emulsifiers, etc.), the latter being selected from those which are stable in alkaline media.

Examples of catalysts include: organic hydroperoxides such as cumene, diisopropylbenzene, para, menthane, etc., persulfates such as sodium, potassium or ammonium.

<img file="PT78025B_D0003.tif" />

Emulsifying agents which may be present may include anionic agents such as: fatty acid salts, alkylsulfates, alkylsulfonates, arylsulfates, arylsulfonates, alauylarylsulfates, alkylsulfonates, alkali metal alkylphosphates; nonionic agents such as polyethoxylated fatty alcohols, alkylphenolpolyethoxylated fatty acids, polyethoxylated fatty acids.

The aqueous dispersion of nonionogenic ethylene monomer copolymer and alkyl acrylate may contain 20 to 6% by weight of dry matter and preferably 40 to 55% by weight of dry matter, with a particle diameter of 0, 05 to 0.5 µm.

It is called small hydride extinct aerial lime, a fat lime obtained by calcination of rock.

<img file="PT78025B_D0004.tif" />

limestone followed by an extinction with water, its hydraulics index preferably being less than 0.015.

The lime hydraulic content is given by the ratio of the most acidic to the most alkaline elements:

SiG_no + Al ~, G-> + c and c ₃ i --- CaO + KgO

It has been observed that an extinguished air lime with a hydraulic index of the order of 0.00? gives particularly satisfactory results.

In accordance with the present invention, lime may be applied either in powder form or in dispersion in water.

D-sorbitol may be used either in its pure form or as an aqueous solution of any concentration.

The amounts of the different components of the paint-disperse are the lime that is the object of the present invention allow the volume pigment concentration (CFV), i.e. the volume ratio of the Z-powder (ies) pigment (s). ) + lime + optionally fillers, contained in the ink for the corresponding dry extract (ie alloy dry extract + dry powder + dry adjuvants), of the order of 15 to 30% and preferably from 4c to 70% order ·

In accordance with the present invention, the lime dispersion paint may conveniently contain:

- 1 ° C to 85 ° C, preferably 4θ to 320 ° C by weight of lime relative to the weight of dry binder extract;

0.1 to 2 preferably 0.5 to 1.5% by weight of D-soobol in relation to the weight of lime;

- 45 to 35> by weight of dry extract (ie extract if

<img file="PT78025B_D0005.tif" />

binder weight + dry powder + dry adjuvants) with respect to the weight of the paint dispersion, said dry extract weight being conveniently 45 to 65 for a fluid paint and 65 to 35 for a coating.

Among the pigments that may be present may be cited, in particular, rutile titanium dioxide or anatase.

The amount of pigments to use depends on the type of ink desired. Said amount of pigment may range from 10 to 96% by weight of the powdery matter, depending on whether a dull or glossy paint is to be prepared.

Among the common basic pH stable dispersing agents which may be present, alkaline polyacrylates, for example sodium ones, may be particularly cited. These may be used in an amount of the order of 0.15 to 2% by weight of dry matter relative to the total weight of the paint.

Among the commonly used basic pH thickening agents which may be present are water soluble nonionic polyurethanes in aqueous solution. These may be used in an amount of the order of 0.15% by weight of dry matter relative to the total weight of the paint.

The lime dispersion paint which is the object of the present invention may also optionally contain:

- coalescing agents such as ethylene glycol or diethylene glycol monobutyl ether, ethylene glycol, propylene glycol or dipropylene glycol phenyl ether or xhite-spirit type products which have a small content of aromatic compounds, to decrease if necessary. minimum formation temperature.

binder film (for example to a temperature of 0 ° C or less) within a range of 3 θ parts by weight to B10 parts binder;

antifoam agents, for example dimethylpolysiloxanoic oil type, in order to prevent the possible formation of foams as a result of mechanical agitation;

antifreeze agents, for example alcohols, alkanediols (1,2'-propanediol, diethylene glycol), polyethylene glycols in an amount up to 10% of the ink weight.

The present invention also relates to the process of preparing the lime paint dispersion described above.

Said lime dispersion paint can be obtained by mixing with stirring of its various constituents in the amounts indicated above according to the rules of the skilled artisan.

Preferably, said lime dispersion paint may be prepared by incorporating a pigment paste comprised of pigment dispersed in aqueous or hydroalcoholic medium, in a mixture consisting of extinct airborne lime with a low hydraulicity index dispersed within a medium containing contains mare, D-sorbitol and the binder; It may also be prepared by incorporating into the previously prepared pigment paste the various additives, binder and lime which are dispersed in the medium.

Pigment dispersion as well as lime are favored by the use of a dispersing agent as described above.

The dispersion paint which is the subject of the present invention is stable in storage if noticeable evolution of its viscosity over time.

This dispersion paint is easily applied to surfaces such as those based on hydraulic binders, stucco, wood and wood agglomerates by conventional methods (roller, air gun, brush, etc.).

After drying, the ink forms a film which has good properties, in particular dry adhesion and wet abrasion resistance.

In addition, it was observed that the ink constituting obp. The present invention having a pK of at least 12 and having filmogenic characteristics (since coalescence is by water separation) is not influenced by either an excess of basicity or an excess of water. It can therefore be applied to a hydraulic binder-based surface very shortly after the surface has been peeled off (eg 2 or 3 days).

This is a particularly important advantage as it is generally accepted to only coat or strap the surfaces based on hydraulic binders when their moisture content is less than 5 λ θ θ and its lower pK ε 12, ο, usually clearing approximately one month after deburring.

The following examples are given for inductive purposes and cannot be construed as limiting the scope and spirit of the present invention.

curemο

Lime Mixing and Dispersion

Example 1

<img file="PT78025B_D0006.tif" />

Mix in a 20 liter paint disperser:

- 255 parts by weight of an aqueous dispersion of styrene butyl acrylate copolymer having the following characteristics:

- styrene / butyl acrylate weight ratio: approximately 50/50

<img file="PT78025B_D0007.tif" />

- amount of dry extract

- emulsifiers

-catalyst

- grain diameter

<img file="PT78025B_D0008.tif" />

- minimum film formation temperature

- viscosity (measured at 20 ° C in the viscometer)

Broockfield at 5 rpm): about 50: sodium alkyl sulfonate and oxyethylenated alkylphenol: ammonium persulfate: between 0.05 and 0.4-0 µm: 16 ° C: 50 m.Pa.s

- 37 parts of 1,2-pronanediol

- 150 parts water - 5 parts 70% aqueous solution of D-sorbitol

- 5.5 parts of CCATEX ER / 3 as dispersing agent (acrylic copolymer salt in aqueous solution) sold by COATEX Company.

NAPSOL PFPL · as a coalescing agent (dipropyl anoglycol phenyl ether) marketed as

<img file="PT78025B_D0009.tif" />

<td></td><td>by Β. P.</td><td>Chimie;</td>

<td> _ 4</td><td>parts of</td><td>vhite-spirit ”;</td>

<td> - 315</td><td>parts of</td><td>extint air lime</td>

<td></td><td>following</td><td> • •</td>

<td></td><td>- index</td><td>hydraulic</td>

- '' iscoside ε 20 ° 0 and 75o

- average particle size

- rejection on sieve

- Pigment paste

<img file="PT78025B_D0010.tif" />

: Li, uC72 g / 1: 0.5 poises: 7 ztm: 4.23 /

<img file="PT78025B_D0011.tif" />

In a conventional manner a pygmy paste is prepared. whose components are as follows:

- 13 parts 1,2-propanediol

6.5 parts of water

1.5 parts COATEX BR Dispersing Agent / 3 parts KCPCO 8034 Anti-Foaming Agent, available from DIAMOND SEAMROCK

- 60 parts RL 68 titanium oxide, sold by TEANN and MULECUSE

The pigment paste is then incorporated into the dispersion of.

lime.

The ink obtained has the following characteristics:

- dry extract: approximately 60%

- P / L (dry pigment / binder by weight): 2,94 / 1

- CPV: approximately 55

- Brookfiel RVT viscosity (2.5 rpm)

- initial: 3400 m.Pa.s

- after 500 h at 20 ° C: 8000 m.Pa.s

<td>- years 500 h ε 40 ° 0</td><td> 10000</td><td>m.Pa. s</td>

<td>Brookfield RVT viscosity (50 rpm)</td><td></td><td></td>

<td>- initial</td><td> : 2200</td><td>m.Fa .s</td>

<td>- after 500 h at 20 ° C</td><td> : 2100</td><td>m.Pa.s</td>

<td>-after .500 h at 40 ° C</td><td> : 3500</td><td>m.Pa.s</td>

<td>Dry pullout resistance</td><td></td><td></td>

<img file="PT78025B_D0012.tif" />

This experiment is carried out with a 2 cm wide adhesive tape (adhesive according to Rll 30.03 °) applied uniformly over a width of the layer (previously incised to the support) and then peeled off with a rapid and continuous movement.

<img file="PT78025B_D0013.tif" />

- 3 surfaces

- Ink layer thickness

- Results: wood, fiber cement, glass: 15 and 30 microns: no tear on the three surfaces, whether the layer is 15 microns or 30 microns thick.

- Wet abrasion resistance

The experiment is performed with an abrasimeter having a charge of 1000 g.

- surface

- result: fiber cement: good for 15 micron layer and 30 micron layer

The result is considered good when the proportion of des.

POFUW-A!

Spend less than 50% after waxing of genes.

10,000 to 20,000 pass- Folding experience

Evaluation of the softness of the layers - according to the KFT Standard 3 ° · ° 4θ.

- surface-diameter of the mandrel

- duration of movement

- result: polyethylene: 1 cm: 10 seconds: no slits for a 15 micron layer: no slits for a 3θ micron layer

Example 2

As in example 1, an ink is prepared from:

- a lime dispersion obtained by mixing:

100 parts of the styrene butyl acrylate binder used in example 1;

parts of NAPSOL PPE 4 (moncpropylene glycol phenyl ester) marketed by BP Chimie; 1.5 psf white spirit;

- ICO parts of water;

1.5 parts of 70% D-sorbitol aqueous solution; 1.7 lime lime used in example 1

- and a pigment paste obtained by mixing:

1,2-propanediol parts η

- 2 parts water

- 0.9 parts of NOPCO 3034 antifoam

- 0.7 parts of-ÇOATEX BR / 3

- 27 parts of RL 68 titanium oxide

<img file="PT78025B_D0014.tif" />

The ink obtained has the following characteristics:

- dry extract: approximately 57 F

- P / L: 3.24 / 1

- CPV: approximately 57%

- Brookfield viscosity at 20 ° 0 in m.pg.s - at 2.5 rpm: 9000

- at 50 rpm: 900 nm example 3

As in example 1, an ink is prepared from:

- a lime dispersion obtained by mixing:

- 100 parts of the butyl styrene acrylate binder used in example 1 70 pates of water parts of butyldiglycol

1.5 parts uhite spirit 70 parts aqueous solution 70 d of D-sorbitol

1.5 parts of COATEX BR / 3

- 100 parts of lime used in example 1

- and a pigment paste obtained by mixing:

- 5.8 parts of 1,2-propanediol

- 3.2 parts of water

-0.9 parts of antifoam> '0PC0 3θβ4

- 0.7 part of COATEX BR / 3

- 27 parts of RL 68 titanium oxide

The ink obtained has the following characteristics

<img file="PT78025B_D0015.tif" />

Seco dry extract

P / L

Brookfield CPV viscosity at 20 ° C in m.Pa.s

- at 2.5 rp^m

- at 50 rpm% approximately 2.54 / 1

50.5 / approx.

Sooo

800

Example 4

Mix in a paint disperser:

<td> - 230</td><td>share '</td><td>in</td><td>Water</td><td></td><td></td>

<td>- 5th</td><td>parts</td><td>in</td><td>1,2-propanediol</td><td></td><td></td>

<td> - 5</td><td>parts</td><td>in</td><td>aqueous solution s</td><td>70 of</td><td>D-sorbitol</td>

<td>- s</td><td>parts</td><td>in</td><td>C0ATEX BR / 3</td><td></td><td></td>

<td>- 6th</td><td>parts</td><td>in</td><td>styrene binder</td><td>-acrylate</td><td>1 butyl</td>

<td></td><td>used</td><td>at the</td><td>example 1</td><td></td><td></td>

<td> - 5</td><td>parts</td><td>gives</td><td>lime used in</td><td>example</td><td> 1</td>

<td> 2</td><td>parts</td><td>in</td><td>NOFCO 8034</td><td></td><td> -</td>

<td> - 60</td><td>parts</td><td>in</td><td>titanium oxide</td><td>Έ, τ kQ XtJ-J V w »</td><td></td>

<td> - 345</td><td>parts</td><td>gives</td><td>lime used in</td><td>example</td><td> 1.</td>

The mixture is then stirred for 20 minutes.

The composition obtained is then adjusted by the addition of:

- 165 parts of utiw styrene butyl acrylate binder

OOATEX BR / 100 (which contains

<td>freeze</td><td>at the</td><td>example</td><td> 1</td>

<td>parts</td><td>in</td><td>PAFSOL</td><td>PPF ^x 2</td>

<td>parts</td><td>in</td><td>vhite-</td><td>spirit</td>

<td>parts</td><td>in</td><td>agent</td><td>thickener</td>

<img file="PT78025B_D0016.tif" />

It has 10% water soluble polyurethane not sold by OOATEX.

the ionic)

<img file="PT78025B_D0017.tif" />

The ink obtained has the following characteristics:

- dry extract: approximately 57 7 °

- P / L. : 3.65 / 1

- Brookfield viscosity at 20 ° C in m.Pa.s

- at 2.5 rpm: 10,000

- at 50 rpm: 1,580 with

Example 5

Preparation of a coating applicable in 1 mm thickness.

In a conventional manner a pigment paste is made of the following composition:

- 3.1 parts 1,2-propanediol 1.55 parts water

- 0.35 part of OOATEX BR / 3

- 0.47 part of KAPCÓ 3034 antifoam

- 14,28 parts of titanium oxide RL 68 The following is incorporated with stirring:

- .1.1 parts of water t

8.33 parts 1,2-propanediol

0.71 part 70% aqueous solution of D-sorbitol

<img file="PT78025B_D0018.tif" />

1.3C parts COATEZ EE / 3

- 100 parts of styrene butyl acrylate dispersion at 50 ° C of dry extract used in example 1

4.76 parts of NAPSOL EPBL,

- 35.70 parts of lime used in example 1

- 23, SC parts of crystallized calcium carbonate with an average diameter of 40 microns cut to 10C microns

- 142.35 parts of crystallized calcium carbonate with 100 to 7CC microns.

Characteristics of this coating 'Dry extract P / L ratio