CN101050330A - Aqueous industrial baking varnish - Google Patents

Abstract

This invention discloses a single-component waterborne epoxy medium-temperature-curing varnish, which comprises: water 80-150 parts, epoxy resin-1422 300-400 parts, curing agent dicyandiamide 5-10 parts, wetting agent StarFactant-20 0.4-0.8 part, defoamer FoamStar-MF324 0.2-0.3 part, preservative Alex-251 0.4-1.0 part, thickener DSX3551 3.0-10.0 parts, and flash rust inhibitor Alcophor-40 2.0-5.0 parts. The waterborne epoxy medium-temperature-curing varnish has a curing temperature of 150-180 deg.C, and a hardness of 2-4H. The waterborne epoxy medium-temperature-curing varnish has such advantages as no organic solvent volatilization, low VOC, simple production, and convenient storage and transportation. The coating film has such advantages as high hardness, high wear resistance, high compactness, and high chemical resistance. The waterborne epoxy medium-temperature-curing varnish can be used to coat metal matrices, and protect some heat-resistant plastic matrices.

Description

A kind of aqueous industrial baking varnish

[technical field]

The present invention relates to the water-borne coatings field, particularly be a kind of industrial water-based baking varnish and curing process.

[background technology]

The traditional high VOC coating of China is still occupied woodwork coating, plastic paint, universal protective system market, about 700,000～800,000 t of total amount, present high VOC solvent based coating accounts for more than 60% of coating output, nearly 1,000,000 t, reduce 100g/L as if VOC is limited the quantity of, will reduce organic solvent emission amount 100,000 t.Therefore, Eleventh Five-Year Plan target and emphasis are that the coating products kind develops to the low pollution of environment-friendly type, less energy-consumption, Water-borne modification, high solids content, powdered kind direction.

The coating products of China's outlet suffers the environmental protection barrier.In recent years, government supports and encourages water-borne coatings, the technical study of water-based high-performance coating and product development energetically.All obtained significant progress in water-borne coatings state of the art, practical application and marketing, water-borne wood coating, aqueous rust-proof coatings become the topic that coating circle is paid close attention to.And there is imperfection aspect hardness, wear resistance, the water tolerance at the common onepot coating in aqueous industrial coating field, and price height, therefore be difficult to from the cost performance aspect for the human consumer accepts, make water-borne wood coating and water-based industrial paint be in time-out and look around the stage.

[summary of the invention]

The purpose of this invention is to provide a kind of single-component aqueous epoxy baking finish, this varnish is used for the metallic surface 150～180 ℃ of curing.Hardness can reach 2H-4H.

A kind of single-component aqueous epoxy intermediate temperature setting varnish consists of by weight:

80～150 parts in water;

1,422 300～400 parts of Resins, epoxy;

5～10 parts of curing agent dicyandiamides;

Wetting agent StarFactant ^_20,0.4～0.8 part;

Defoamer FoamStar ^_MF324,0.2～0.3 part;

Sanitas, 251 0.4～1.0 parts of Alex;

Thickening material DSX3551,3.0～10.0 parts;

The anti-rust agent Alcophor that dodges ^_40 2.0～5.0 parts

Aqueous industrial varnish of the present invention is used for the metallic surface 150～180 ℃ of curing, and hardness can reach 2H～4H, and the organic solvent-free volatilization belongs to environmental protection coating material, reduces VOC; Produce and accumulating simple and convenient, film have the bi-component high-hardness degree, high-wearing feature, high compactness and anti-chemical; Overcome the defective of Water-borne modification industrial baking lacquer, some performance even surmounted solvent type like product; Can be used for the metal base application, also can be used for some resistant to elevated temperatures plastic basis material protection.

[embodiment]

What the present invention adopted is the single-component water-based coating of latent, and the coating ambient stable does not react, and chemical curing reaction takes place after giving certain temperature, and real is that two components are coating material solidified.Production and accumulating are simple and convenient, and filming has two component high rigidity, high-wearing feature, high compactness and anti-chemical.Selection and adjustment by technology, avoided the obstacle of the Water-borne modification maximum of industrial baking lacquer, as: " quick-fried bubble " problem during thick being coated with, the volatilization of water the surface of paint film is influenced water tolerance problem after problem, the film forming, construction puzzlement that water dilution peak causes and difference of some physical and chemical performance aspects or the like, the performance of aqueous industrial baking lacquer has obtained significant progress, the defective that some behaviours in the past denounce is greatly improved, some performance even surmounted solvent type like product.This product can be used for the metal base application, also can be used for some resistant to elevated temperatures plastic basis material protection.

Employed aqueous epoxy emulsion is that word is emulsified in the water behind the solid epoxy hydrophilic modifying among the present invention, and active ingredient is 50～60%, and epoxy equivalent (weight) is 550.0～1120g/eq, viscosity be 2000-6000mPa.s (RV4,20rpm); Latent curing agent Dyhard RU 100 white crystal, 207～209 ℃ of fusing points, water-soluble slightly and ethanol is insoluble in ether and benzene, reactive hydrogen equivalent 21g/eq.

Wetting agent among the present invention is a nonionogenic tenside, composition is polyether-modified polysiloxane or amber sulfonate, a kind of novel low-foaming wetting agent, unique high many hydrophobic groups of cladodification structural polymer, the behavior of performance good wet, and do not form stable bubble, and be a kind of wetting agent with their defoaming function, the surface tension of the aqueous solution (0.5%) is 20 dynes per centimeter ²Defoamer is a hyperbranched polymer, and not siliceous, oily, solvent and solid matter have certain wetting function; Thickening material is polyacrylic acid and polyurethane associative thickener; Sanitas is an isothiazolinone.

The production technique of aqueous industrial varnish: in water, add the solid curing agent dicyandiamide successively and be stirred to dissolving fully, add aqueous epoxy emulsion, wetting agent, defoamer, mould inhibitor, anti-rust agent, the thickening material of dodging then respectively, obtain finished product oyster white coating at last.

Curing process: 205 ℃, 0.5 hour.

During the present invention is raw materials used, epoxy resin latex WATERPOXY 1422, the anti-rust agent Alcophor that dodges ^_40, wetting agent StarFactant ^_20, sanitas Alex 251, defoamer FoamStar ^_MF324, thickening material DSX3551 provide by COGNIS company; Curing agent dicyandiamide is a Ningxia Ying Lite company product.

Example 1:

Weighing 110.0g water; 6.7g curing agent dicyandiamide; 0.4g sanitas Alex 251,0.8g wetting agent StarFactant ^_20; 0.2g defoamer FoamStar ^_MF324; 360g epoxy resin latex WATERPOXY 1422; 7g thickening material DSX3551, the anti-rust agent Alcophor that dodges of 2.0g ^_40.In water, add the solid curing agent dicyandiamide successively and be stirred to dissolving fully, add aqueous epoxy emulsion, wetting agent, defoamer, mould inhibitor, anti-rust agent, the thickening material of dodging then respectively, obtain finished product oyster white coating at last.

Example 2:

Weighing 150.0g water; 10.0g curing agent dicyandiamide; 0.7 sanitas Alex 251,0.4g wetting agent StarFactant ^_20; 0.3g defoamer FoamStar ^_MF324; 400g epoxy resin latex WATERPOXY 1422; 10g thickening material DSX3551, the anti-rust agent Alcophor that dodges of 3.5g ^_40.In water, add the solid curing agent dicyandiamide successively and be stirred to dissolving fully, add aqueous epoxy emulsion, wetting agent, defoamer, mould inhibitor, anti-rust agent, the thickening material of dodging then respectively, obtain finished product oyster white coating at last.

Example 3:

Weighing 80.0g water; 5.0g curing agent dicyandiamide; 1.0 sanitas Alex 251,0.6g wetting agent StarFactant ^_20; 0.25g defoamer FoamStar ^_MF324; 300g epoxy resin latex WATERPOXY 1422; 3g thickening material DSX3551, the anti-rust agent Alcophor that dodges of 5.0g ^_40.In water, add the solid curing agent dicyandiamide successively and be stirred to dissolving fully, add aqueous epoxy emulsion, wetting agent, defoamer, mould inhibitor, anti-rust agent, the thickening material of dodging then respectively, obtain finished product oyster white coating at last.

Embodiment gained elastic coating performance such as following table:

	Package stability (normal temperature)	Condensate performance
						Outward appearance	Sticking power	Hardness	Shock-resistant
		Example 1	June is no abnormal	Transparent no abnormal	0 grade					4H	10cm
Example 2	June is no abnormal					Transparent no abnormal	0 grade	2H	15cm
		Example 3	June is no abnormal	Transparent no abnormal	0 grade					2H	15cm

Claims (1)

1, a kind of single-component aqueous epoxy intermediate temperature setting varnish consists of by weight:

80～150 parts in water;

1,422 300～400 parts of Resins, epoxy;

Solidifying agent, 5～10 parts of Dyhard RU 100s;

Wetting agent StarFactant ^_20,0.4～0.8 part;

Defoamer FoamStar ^_MF324,0.2～0.3 part;

Sanitas, 251 0.4～1.0 parts of Alex;

Thickening material DSX3551,3.0～10.0 parts;

The anti-rust agent Alcophor that dodges ^_40 2.0～5.0 parts.