Polyurethane finish paint with super-long activation period and application thereof

Abstract

The invention provides a polyurethane finishing coat with an ultra-long activation period and application thereof, and belongs to the field of coatings. The main agent comprises the following components in percentage by mass: 45-70% of acrylic resin KN3378H, 1-3% of a dispersing agent, 10-20% of titanium dioxide, 0.5-1% of a wetting defoaming agent, 0.1-0.5% of a wetting agent, 0.1-0.5% of carbon black, 10-20% of water, 0.2-0.5% of a thickening agent and 1-8% of a cosolvent; the curing agent comprises 60-80% of an isocyanate curing agent 297 and 20-40% of propylene glycol methyl ether acetate. The acrylic resin KN3378H is matched with the isocyanate curing agent 297, the isocyanate curing agent 297 is a water-oil general curing agent and is deviated to be oily, and the acrylic resin KN3378H and the curing agent are slow in compatible reaction, so that the activation period of the polyurethane finish paint is prolonged; and the mass percent of each raw material is limited, so that the activation period is further prolonged.

Description

Technical Field

[0001] The invention relates to the technical field of coatings, and in particular to a polyurethane topcoat with an ultra-long activation period and application thereof. Background Art

[0002] In the rail transit system, the activation period of the topcoat is mostly 2 to 3 hours, and some are as long as 4 to 5 hours. Since the activation period of the coating is greatly affected by temperature, generally the higher the temperature, the shorter the activation period. The activation period is longer in winter and shorter in summer, at 2 to 3 hours. Summary of the invention

[0003] In view of this, the object of the present invention is to provide a polyurethane topcoat with an ultra-long activation period and its application. The polyurethane topcoat of the present invention has a long activation period.

[0004] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0005] The invention provides a polyurethane topcoat with an ultra-long activation period, comprising a main agent and a curing agent which are packaged separately.

[0006] The main agent comprises the following components in mass percentage: acrylic resin KN3378H 45-70%, dispersant 1-3%, titanium dioxide 10-20%, wetting defoamer 0.5-1%, wetting agent 0.1-0.5%, carbon black 0.1-0.5%, water 10-20%, thickener 0.2-0.5%, cosolvent 1-8%;

[0007] The curing agent comprises the following components in percentage by mass: 29760-80% of isocyanate curing agent and 20-40% of propylene glycol methyl ether acetate.

[0008] Preferably, the main agent includes the following components in mass percentage: acrylic resin KN3378H 55%, dispersant 2%, titanium dioxide 15%, wetting defoamer 0.8%, wetting agent 0.2%, carbon black 0.3%, water 19.8%, thickener 0.5%, and cosolvent 6.4%.

[0009] Preferably, the main agent includes the following components in mass percentage: acrylic resin KN3378H 60%, dispersant 2%, titanium dioxide 15%, wetting defoamer 0.8%, wetting agent 0.2%, carbon black 0.3%, water 15.4%, thickener 0.3%, and cosolvent 6%.

[0010] Preferably, the main agent includes the following components in percentage by mass: acrylic resin KN3378H 65%, dispersant 2%, titanium dioxide 15%, wetting defoamer 0.8%, wetting agent 0.2%, carbon black 0.3%, water 12.4%, thickener 0.3%, and cosolvent 4%.

[0011] Preferably, the main agent includes the following components in mass percentage: acrylic resin KN3378H 70%, dispersant 2%, titanium dioxide 15%, wetting defoamer 0.8%, wetting agent 0.2%, carbon black 0.3%, water 10.4%, thickener 0.3%, and cosolvent 1%.

[0012] Preferably, the cosolvent is dipropylene glycol butyl ether.

[0013] Preferably, the wetting agent is wetting agent 4100.

[0014] Preferably, the mass ratio of the main agent to the curing agent is 3:1.

[0015] Preferably, the curing agent comprises the following components in percentage by mass: 29770% isocyanate curing agent and 30% propylene glycol methyl ether acetate.

[0016] The present invention also provides the use of the polyurethane topcoat with an ultra-long activation period described in the above technical solution in the field of rail transportation.

[0017] The invention provides a polyurethane topcoat with an ultra-long activation period, comprising a main agent and a curing agent which are separately packaged, wherein the main agent comprises the following components in mass percentage: 45-70% of acrylic resin KN3378H, 1-3% of a dispersant, 10-20% of titanium dioxide, 0.5-1% of a wetting and defoaming agent, 0.1-0.5% of a wetting agent, 0.1-0.5% of carbon black, 10-20% of water, 0.2-0.5% of a thickener, and 1-8% of a cosolvent; and the curing agent comprises the following components in mass percentage: 60-80% of an isocyanate curing agent 297 and 20-40% of propylene glycol methyl ether acetate.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The present invention adopts acrylic resin KN3378H in combination with isocyanate curing agent 297. Isocyanate curing agent 297 is a universal curing agent for water and oil, which tends to be oily. The acrylic resin KN3378H and the curing agent are compatible and react slowly, thereby increasing the activation period of the polyurethane topcoat. Titanium dioxide has good hiding power, and dispersants, wetting defoamers, wetting agents, thickeners, cosolvents and propylene glycol methyl ether acetate do not affect the activation period. Combined with the limitation of the mass percentage of each raw material, the comprehensive effect further increases the activation period. The data of the embodiment show that the activation period of the polyurethane topcoat of the present invention is 16 to 24 hours. DETAILED DESCRIPTION

[0020] The invention provides a polyurethane topcoat with an ultra-long activation period, comprising a main agent and a curing agent which are packaged separately.

[0021] The main agent comprises the following components in mass percentage: acrylic resin KN3378H 45-70%, dispersant 1-3%, titanium dioxide 10-20%, wetting defoamer 0.5-1%, wetting agent 0.1-0.5%, carbon black 0.1-0.5%, water 10-20%, thickener 0.2-0.5%, cosolvent 1-8%;

[0022] The curing agent comprises the following components in percentage by mass: 29760-80% of isocyanate curing agent and 20-40% of propylene glycol methyl ether acetate.

[0023] In the present invention, unless otherwise specified, the raw materials used are all commercially available products in the art.

[0024] In the present invention, the main agent preferably includes the following components in mass percentage: acrylic resin KN3378H 55%, dispersant 2%, titanium dioxide 15%, wetting defoamer 0.8%, wetting agent 0.2%, carbon black 0.3%, water 19.8%, thickener 0.5%, cosolvent 6.4%; or

[0025] The composition comprises the following components in percentage by mass: acrylic resin KN3378H 60%, dispersant 2%, titanium dioxide 15%, wetting defoamer 0.8%, wetting agent 0.2%, carbon black 0.3%, water 15.4%, thickener 0.3%, cosolvent 6%; or

[0026] The composition comprises the following components in percentage by weight: acrylic resin KN3378H 65%, dispersant 2%, titanium dioxide 15%, wetting defoamer 0.8%, wetting agent 0.2%, carbon black 0.3%, water 12.4%, thickener 0.3%, cosolvent 4%; or

[0027] The invention comprises the following components in percentage by mass: 70% of acrylic resin KN3378H, 2% of dispersant, 15% of titanium dioxide, 0.8% of wetting and defoaming agent, 0.2% of wetting agent, 0.3% of carbon black, 10.4% of water, 0.3% of thickener and 1% of cosolvent.

[0028] In the present invention, the cosolvent is preferably dipropylene glycol butyl ether (DPNB).

[0029] In the present invention, the acrylic resin KN3378H is preferably purchased from Guangdong Kelisen Resin Co., Ltd.

[0030] In the present invention, the dispersant is preferably BYK-190 dispersant.

[0031] In the present invention, the titanium dioxide is preferably titanium dioxide 706.

[0032] In the present invention, the water is preferably deionized water.

[0033] In the present invention, the wetting and defoaming agent is preferably 104E wetting and defoaming agent.

[0034] In the present invention, the wetting agent is preferably 4100 wetting agent.

[0035] In the present invention, the thickener is preferably thickener 8W.

[0036] In the present invention, the carbon black is preferably carbon black MA-100.

[0037] In the present invention, the mass ratio of the main agent to the curing agent is preferably 3:1.

[0038] In the present invention, the curing agent comprises the following components in mass percentage: 29770% of isocyanate curing agent and 30% of propylene glycol methyl ether acetate (PMA).

[0039] In the present invention, the isocyanate curing agent 297 is preferably purchased from Jiangsu Fuqisen New Materials Co., Ltd.

[0040] The present invention has no special limitation on the preparation method of the polyurethane topcoat with ultra-long activation period, and the topcoat can be prepared by a preparation method of a composition well known to those skilled in the art.

[0041] In the present invention, the preparation method of the main agent preferably comprises pre-mixing, grinding and blending performed in sequence.

[0042] In the present invention, part of water, part of wetting defoamer, dispersant, titanium dioxide and carbon black are preferably mixed for pre-mixing to obtain pre-mixed material.

[0043] In a specific embodiment of the present invention, it is preferred to first add the portion of water, start stirring, and the dispersion frequency is 200 to 500 rpm, then add the portion of wetting defoaming agent, stir for 2 to 3 minutes, and then add the dispersant, titanium dioxide and carbon black in sequence, stirring for 3 to 5 minutes after each addition before adding the next item, and increase the stirring speed to 300 to 700 rpm. After adding, continue stirring for 15 minutes to complete the pre-refining.

[0044] After obtaining the pre-mixed material, the pre-mixed material is ground, and then flushed with the remaining water to obtain a grinding slurry.

[0045] The present invention has no particular limitation on the ratio of the partial water to the remaining water, and any ratio may be used.

[0046] In the present invention, the particle size of the polishing slurry is preferably ≤15 μm, more preferably ≤10 μm.

[0047] In the present invention, the grinding is preferably carried out in a sand mill, and the cooling water and slurry flow rates are adjusted so that the grinding temperature is preferably <50°C, the grinding pressure is preferably <0.2MPa, and monitoring and recording are preferably performed every 20 minutes; the grinding is carried out in an inverted cylinder, and the fineness is self-checked and recorded each time. After grinding to less than 15μm, samples are taken for inspection. If the fineness is qualified, the obtained pre-refined slurry is poured into a blending cylinder and ground with the remaining water to obtain a grinding slurry.

[0048] After obtaining the grinding slurry, the present invention mixes the grinding slurry, acrylic resin KN3378H, a wetting agent, a residual wetting defoaming agent, a thickener and a co-solvent to obtain the main agent.

[0049] The present invention has no particular limitation on the ratio of the partial wetting defoamer to the remaining wetting defoamer, and any ratio may be used.

[0050] In a specific embodiment of the present invention, the acrylic resin KN3378H and the wetting agent are preferably added to a mixing cylinder containing a grinding slurry, dispersed at a speed of 300 to 700 rpm for 5 minutes, and then the remaining wetting and defoaming agent is added, the stirring speed is increased to 500 to 900 rpm, stirred for 60 to 90 minutes, the stirring speed is adjusted to 300 to 700 rpm, and then the thickener and the co-solvent are added in turn, stirring for 3 to 5 minutes after each addition, and then adding the next item, and finally stirring for 20 minutes, and sampling for inspection.

[0051] The present invention also provides the use of the polyurethane topcoat with an ultra-long activation period described in the above technical solution in the field of rail transportation.

[0052] The present invention has no particular limitation on the specific manner of the application, and any manner familiar to those skilled in the art may be used.

[0053] The technical solutions in the present invention will be described clearly and completely below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0054] Example 1

[0055] Preparation process of the main agent of polyurethane topcoat with ultra-long activation period:

[0056] First add the water, start stirring, the dispersion frequency is 500 rpm, then add the wetting defoamer, stir for 3 minutes, then add the dispersant, titanium dioxide and carbon black in sequence, stir for 3 to 5 minutes after each addition, and then add the next item, increase the stirring speed to 700 rpm, continue stirring for 15 minutes after adding, and complete the pre-refining; grind the obtained pre-refined material, pass it through a sand mill, adjust the cooling water and slurry flow rate, make the grinding temperature 40°C, the grinding pressure 0.15MPa, monitor and record every 20 minutes, reverse the cylinder for grinding, self-check the fineness each time and record it, grind to 1 5μm or less, take samples for inspection, if the fineness is qualified, put the obtained pre-refined slurry into the mixing cylinder, grind with the remaining water to obtain the grinding slurry; add the acrylic resin KN3378H and the wetting agent into the mixing cylinder containing the grinding slurry, disperse at 700 rpm for 5 minutes, then add the remaining wetting defoaming agent, increase the stirring speed to 900 rpm, stir for 90 minutes, adjust the stirring speed at 700 rpm, and then add the thickener and the co-solvent in turn, stir for 5 minutes after each addition, and finally stir for 20 minutes, take samples for inspection, and obtain the main agent of the polyurethane topcoat with an ultra-long activation period.

[0057] The main agent formulas of Examples 1 to 4 and Comparative Examples 1 to 3 are shown in Table 1. The resin in Examples 1 to 4 is acrylic resin KN3378H (purchased from Guangdong Kelisen Resin Co., Ltd.), the resin in Comparative Example 1 is 570 resin (purchased from Zhuhai Lianku Chemical Group), the resin in Comparative Example 2 is 8287 resin (purchased from Jiangsu Fuqisen New Materials Co., Ltd.), and the resin in Comparative Example 3 is 8233 resin (purchased from Jiangsu Fuqisen New Materials Co., Ltd.).

[0058] The preparation process of the main agent of Examples 2 to 4 and Comparative Examples 1 to 3 is the same as that of Example 1, the only difference being the type and amount of the raw materials.

[0059] Table 1 Main agent formula (wt%) of Examples 1 to 4 and Comparative Examples 1 to 3

[0060]

[0061]

[0062] The curing agent of the embodiment and the comparative example includes the following components in mass percentage: 70% of isocyanate curing agent 297 (purchased from Jiangsu Fuqisen New Materials Co., Ltd.) and 30% of propylene glycol methyl ether acetate.

[0063] The mass ratio of the main agent to the curing agent in the polyurethane topcoat of the embodiment and the comparative example is 3:1.

[0064] Activation period test results (test temperature is 25°C):

[0065] The activation period of Example 1 is 16 hours, the activation period of Example 2 is 24 hours, the activation period of Example 3 is 22 hours, the activation period of Example 4 is 20 hours, the activation period of Comparative Example 1 is 9 hours, the activation period of Comparative Example 2 is 10 hours, and the activation period of Comparative Example 3 is 11 hours. It can be seen that the activation period of Example 2 is the best.

[0066] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A polyurethane topcoat with an ultra-long activation period, characterized in that: Including independent packaging of main agent and curing agent, The main agent comprises the following components in mass percentage: acrylic resin KN3378H 45-70%, dispersant 1-3%, titanium dioxide 10-20%, wetting defoamer 0.5-1%, wetting agent 0.1-0.5%, carbon black 0.1-0.5%, water 10-20%, thickener 0.2-0.5%, cosolvent 1-8%; The curing agent comprises the following components in percentage by mass: 29760-80% of isocyanate curing agent and 20-40% of propylene glycol methyl ether acetate.

2. The polyurethane topcoat according to claim 1, characterized in that The main agent comprises the following components in percentage by mass: 55% acrylic resin KN3378H, 2% dispersant, 15% titanium dioxide, 0.8% wetting defoamer, 0.2% wetting agent, 0.3% carbon black, 19.8% water, 0.5% thickener and 6.4% cosolvent.

3. The polyurethane topcoat according to claim 1, characterized in that The main agent comprises the following components in percentage by mass: 60% acrylic resin KN3378H, 2% dispersant, 15% titanium dioxide, 0.8% wetting defoamer, 0.2% wetting agent, 0.3% carbon black, 15.4% water, 0.3% thickener and 6% cosolvent.

4. The polyurethane topcoat according to claim 1, characterized in that The main agent comprises the following components in percentage by mass: 65% of acrylic resin KN3378H, 2% of dispersant, 15% of titanium dioxide, 0.8% of wetting and defoaming agent, 0.2% of wetting agent, 0.3% of carbon black, 12.4% of water, 0.3% of thickener and 4% of cosolvent.

5. The polyurethane topcoat according to claim 1, characterized in that The main agent comprises the following components in percentage by mass: 70% acrylic resin KN3378H, 2% dispersant, 15% titanium dioxide, 0.8% wetting defoamer, 0.2% wetting agent, 0.3% carbon black, 10.4% water, 0.3% thickener and 1% cosolvent.

6. The polyurethane topcoat according to any one of claims 1 to 5, characterized in that: The cosolvent is dipropylene glycol butyl ether.

7. The polyurethane topcoat according to any one of claims 1 to 5, characterized in that: The wetting agent is wetting agent 4100.

8. The polyurethane topcoat according to any one of claims 1 to 5, characterized in that: The mass ratio of the main agent to the curing agent is 3:

1.

9. The polyurethane topcoat according to claim 1, characterized in that: The curing agent comprises the following components in percentage by mass: 29770% of isocyanate curing agent and 30% of propylene glycol methyl ether acetate.

10. Use of the polyurethane topcoat with an ultra-long activation period as claimed in any one of claims 1 to 9 in the field of rail transportation.

Images