CN116854881B

CN116854881B - A preparation process of lightweight polyurethane model

Info

Publication number: CN116854881B
Application number: CN202310753128.4A
Authority: CN
Inventors: 黄威德; 何保峰; 陈旺皮; 周建修
Original assignee: Zhangzhou Taixing Chemical Coating Co ltd
Current assignee: Zhangzhou Taixing Chemical Coating Co ltd
Priority date: 2023-06-25
Filing date: 2023-06-25
Publication date: 2025-08-08
Anticipated expiration: 2043-06-25
Also published as: CN116854881A

Abstract

The invention provides a preparation process of a lightweight polyurethane model, which comprises a polyurethane surface layer, a polyurethane foaming inner layer and a finishing paint coated on the outer surface of the polyurethane surface layer, wherein the formula of the finishing paint comprises emulsion, a defoaming agent, a PH regulator, a wetting agent, a dispersing agent, a leveling agent, a handfeel agent, a matting agent, a film forming auxiliary agent, a thickening agent and deionized water. The polyurethane model has the advantages that the polyurethane model realizes the light weight, the finishing paint is emulsion A which is sprayed on the polyurethane model and has excellent adhesive force, the wetting agent is organic silicon wetting agent and proper amount of fluorocarbon wetting agent, the matting agent is fumed silica matched with micro wax powder and proper handfeel agent, the finishing paint which has excellent adhesive force, excellent scratch resistance and good handfeel on the surface of the polyurethane model can be prepared, and the requirements of the high-end model can be met.

Description

Preparation process of lightweight polyurethane model

[ Field of technology ]

The invention relates to the technical field of clothing model props, in particular to a preparation process of a lightweight polyurethane model.

[ Background Art ]

The model is an prop for showing the clothing effect of clothing stores, is an indispensable prop for middle and high-grade clothing stores, and has important roles for attracting customers, showing the clothing effect and showing the grade of the clothing stores. The conventional model prop mainly comprises a wooden model and a model manufactured by using wood chips or solid wood, and a model manufactured by injection molding of plastic or PE resin and the like. The two model props are not easy to move in the using process due to heavy weight.

Polyurethane is a polymer material with a carbamate structure, belongs to a reactive polymer material, and is a polymer compound with-NH-CO-O-groups on the main chain, which is called polyurethane. The polyurethane foam material has the advantages of high strength, light weight, easy processing and forming and the like, and is widely applied to various industries.

In view of the problems of the prior art models, the prop model made of polyurethane foam is developed, and the scheme prepares the finishing paint with excellent adhesive force on the surface layer of the polyurethane model according to the problems encountered in the production of the polyurethane model through analysis of the composition and molding of polyurethane materials used for the prop model.

[ Invention ]

The invention aims to solve the technical problems that a prop model in the prior art is heavy and is not easy to move in the use process, and provides a preparation process of a lightweight polyurethane model.

The preparation process of the lightweight polyurethane model comprises a polyurethane surface layer, a polyurethane foaming inner layer and a finish paint coated on the outer surface of the polyurethane surface layer.

Furthermore, the polyurethane surface layer is formed by reacting polyether polyol with polyisocyanate, and the polyurethane foaming inner layer is formed by reacting polyether polyol, polyisocyanate, foaming agent and catalyst.

Further, the catalyst is an organic amine catalyst or an organometallic compound catalyst.

Further, the formula of the finishing paint comprises the following components:

further, the matting agent comprises fumed silica and micro wax powder, and the ratio of the fumed silica to the micro wax powder is 1:1.

Further, the wetting agent is a mixture of an organosilicon wetting agent and a fluorocarbon wetting agent.

Furthermore, the finishing paint also comprises 3-3.5% of handfeel agent, wherein the handfeel agent is a mixture of wax emulsion and organosilicon handfeel agent.

Further, the film forming aid includes a mixture of DPM and DPNB.

Further, the preparation process of the finish paint comprises the following steps:

firstly, adding emulsion into a dispersing cylinder, then sequentially adding a defoaming agent, a PH regulator, a wetting agent, a dispersing agent, a leveling agent and a matting agent at a rotating speed of 500r/min, and then adjusting the rotating speed to 2000-2500 r/min for high-speed dispersion for 30 minutes;

step two, after the rotating speed is regulated to 1500r/min, adding a mixture of a film forming additive and deionized water, and stirring for 10-15 minutes;

and thirdly, adding a thickening agent to adjust the viscosity to be proper.

Further, in the first step, a hand feeling agent is added before the matting agent is added, and the addition sequence of the matting agent is that fumed silica and micro wax powder are sequentially added.

The lightweight polyurethane model has the advantages that the technical problem that the existing model prop is heavy and is not easy to move in the use process is solved, and the light weight of the prop model is realized. The finishing paint is an emulsion A with excellent adhesive force sprayed on a polyurethane model, an organosilicon wetting agent and a proper amount of fluorocarbon wetting agent are used as wetting agents, fumed silica is adopted as a matting agent to be matched with micro wax powder, and a proper handfeel agent is matched, so that the finishing paint with excellent adhesive force, excellent scratch resistance and good handfeel on the surface of the polyurethane model can be prepared, and the requirements of a high-end model can be met.

[ Description of the drawings ]

The invention will be further described with reference to the accompanying drawings in conjunction with the experimental group.

FIG. 1 is a schematic view showing a pinhole-free state after the paint is sprayed in the first embodiment.

FIG. 2 is a schematic diagram showing the pinhole state after the paint spraying in the first embodiment.

FIG. 3 is a graph showing the effect of the finish on the surface of a polyurethane model in the second embodiment.

[ Detailed description ] of the invention

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, based on the embodiments of the invention, which are apparent to those of ordinary skill in the art without inventive faculty, are intended to be within the scope of the invention. Thus, the following detailed description of the embodiments of the invention, as presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, based on the embodiments of the invention, which are apparent to those of ordinary skill in the art without inventive faculty, are intended to be within the scope of the invention.

The invention provides a preparation process of a lightweight polyurethane model, which comprises a polyurethane surface layer, a polyurethane foaming inner layer and a finishing paint coated on the outer surface of the polyurethane surface layer, wherein the polyurethane model is formed by injection molding by adopting a RIM technology. The polyurethane model is composed of a compact polyurethane surface layer and a polyurethane foaming inner layer, wherein the polyurethane surface layer is formed by reacting polyether polyol with polyisocyanate, and the polyurethane foaming inner layer is formed by reacting polyether polyol, polyisocyanate, a foaming agent and a catalyst. The prop model prepared by using the polyurethane material realizes the light weight of the prop model.

The preparation process of the polyurethane foaming inner layer comprises the steps of firstly generating a high polymer by using polyisocyanate and a foaming agent, releasing gas, namely foaming reaction, generating a large amount of heat at the same time, so that the temperature is increased, the reaction of-NH-structure and polyisocyanate contained in the polyurethane synthesis process can be promoted, a three-dimensional net-shaped structure is formed, and the rapid gel of the system is promoted.

Preferably, the foaming agent is a chemical foaming agent, and the polyurethane is foamed by the chemical foaming agent to obtain larger open-cell content. The polyurethane foaming inner layer is sealed in the polyurethane surface layer, has no light coating with the surface, has no requirements on the aperture ratio and the closed pore ratio, and adopts water as a foaming agent due to the requirements of environmental protection, economy and safety.

Preferably, the catalyst is an organic amine catalyst or an organometallic compound catalyst. The catalytic activity of the different catalysts for polyurethane to generate different chemical reactions is different, the catalytic activity 'foaming effect' (the reaction of isocyanate and water) of the organic amine catalyst is larger than the 'gel effect' (the reaction of isocyanate and hydroxyl), and the catalytic activity 'gel effect' of the organic metal compound catalyst is larger than the 'foaming effect'.

In the process of the RIM injection molding of the polyurethane model, a release agent is required to be coated in the mould in advance, the release agent is generally composed of polyether organic silicon, and after the model is molded, the model can be well separated from the mould, but the release agent can remain on the surface of the model, so that the coating on the surface of the model is unfavorable. Therefore, in the surface coating process, a cleaning and polishing process is required to be performed on the surface of the model to remove the residual release agent on the surface. The model coating treatment process comprises the steps of cleaning, sand blasting, putty leveling, sand blasting, priming paint, sand blasting and finishing paint.

Preferably, the formula of the finishing paint comprises 73-77% of emulsion, 0.2-0.4% of defoamer, 0.1% of PH regulator, 0.5-0.6% of wetting agent, 0.4-0.6% of dispersing agent, 0.25-0.35% of flatting agent, 1.8-2.2% of flatting agent, 4-6% of film forming auxiliary agent, 0.9% of thickener and 11.8-17.3% of deionized water. The emulsion A produced by Jiafeng chemical industry is preferably adopted, the main component of the emulsion A is modified acrylic polymer, the curing amount is 42+/-1%, and the minimum film forming temperature (MFT) is 20 ℃.

Preferably, the defoamer is a silicone emulsion. It is preferable to use a Di Gao Xiaopao agent TEGO-825, which has a good defoaming effect and is not liable to cause oil shrinkage.

Preferably, the pH adjustor is made of AMP-95 in the form of Dow.

Preferably, the wetting agent is a mixture of 0.5% silicone wetting agent and 0.1% fluorocarbon wetting agent. The fluorocarbon wetting agent has lower surface tension, excellent dynamic surface tension and high price, is not easy to excessively use, and is easy to generate bubbling phenomenon when sprayed, and the organosilicon wetting agent has excellent static surface tension, has general quick spreading capability and is relatively low in price. Therefore, the excellent cost performance can be achieved by adopting the combination of 0.1 percent of fluorocarbon wetting agent and 0.5 percent of organosilicon wetting agent. The organosilicon wetting agent adopts A-8729 of Lanbo, and the fluorocarbon wetting agent adopts A-1190.

Preferably, the dispersing agent adopts TEGO-752W produced in Di high, is a high polymer dispersing agent, has good dispersing effect on micro wax powder, enables the micro wax powder to be more matched with emulsion, is not easy to float out of the surface of the micro wax powder, and further can improve the storage stability of the micro wax powder in a system.

Preferably, the leveling agent is polyether modified organic silicon. TEGO GLIDE 410, which is a polyether modified organosilicon, is preferably used, and can quickly balance the poor surface tension of 'benard vortex' during coating, so that the flatness of a coating film is improved.

Preferably, the matting agent comprises fumed silica and micro wax powder, and the ratio of the fumed silica to the micro wax powder is 1:1. The micro wax powder is oxidized polyethylene wax powder, is composed of regular spherical particles, has narrow particle size distribution and uniform fineness, can be added into a system, can improve the anti-back adhesion and anti-scratch capabilities of the finish paint, has a specific gravity lighter than water, and can be agglomerated with the time when the micro wax powder is not matched with the emulsion system. The micro wax powder adopts micro wax powder P-2026 produced by winning, and the fumed silica adopts fumed silica matting agent P-2021 produced by winning.

Preferably, the film forming aid comprises a mixture of DPM and DPNB in a ratio of 2:3.DPM (dipropylene glycol methyl ether) has excellent film forming effect, the volatilization rate is low, the improvement of early hardness of a coating film can be reduced, compared with DPNB (dipropylene glycol butyl ether), DPM has poor film forming effect, the volatilization rate is high, and the influence on early hardness of a paint film is low, so that the emulsion can be quickly polymerized to form a film by adopting the combination of DPM and DPNB, the excellent film forming effect can be obtained, and the early hardness can be quickly improved.

Preferably, the thickener is a mixture of a courtesy chemical thickener WT-108 and a Wanhua chemical thickener U-300. Thickener WT-108 is preferably 0.4% and thickener U-300 is preferably 0.5%.

Preferably, the finishing paint further comprises 3-3.5% of handfeel agent, wherein the handfeel agent is a mixture of wax emulsion and organosilicon handfeel agent. The organosilicon handfeel agent adopts A-8714 of blue Bo new material. The wax emulsion is A-8711 of blue bonew material.

Example 1

The embodiment provides a preparation process of a finish paint, which comprises the following steps:

and thirdly, adding a thickening agent to adjust the viscosity to be proper.

Preferably, in the first step, the matting agent is added sequentially with fumed silica and micro wax powder.

The beneficial effects of the topcoats prepared using the topcoat preparation process of this example are further illustrated below by several test groups and comparative groups.

Test group one

The preparation process of the finishing paint comprises the following steps of adding 75% of emulsion A (the curing amount is 42+/-1%, the main component is modified acrylic acid polymer, and the MFT is 20 ℃) in chemical production of Jiafeng in a dispersing cylinder, sequentially adding 0.3% of defoamer, 0.1% of PH regulator, 0.5% of organosilicon wetting agent, 0.1% of fluorocarbon wetting agent, 0.5% of dispersing agent, 0.3% of flatting agent and 2% of flatting agent at the rotating speed of 500r/min, then adjusting the rotating speed to 2000-2500 r/min, then dispersing at a high speed for 30 minutes, adjusting the rotating speed to 1500r/min, then adding 5% of film forming auxiliary agent and 15.3% of deionized water, stirring for 10-15 minutes, and finally adding thickener to adjust the viscosity to a proper viscosity. The film forming auxiliary agent comprises 2% of DPM and 3% of DPNB, the thickener comprises 0.4% of thickener WT-108 and 0.5% of thickener U-300, and the matting agent is a mixture of 1% of fumed silica and 1% of micro wax powder.

Test group two

The preparation process of the finishing paint comprises the following steps of adding 73% of emulsion A (the curing amount is 42+/-1%, the main component is modified acrylic acid polymer, and the MFT is 20 ℃) in chemical production of Jiafeng in a dispersing cylinder, sequentially adding 0.3% of defoamer, 0.1% of PH regulator, 0.5% of organosilicon wetting agent, 0.1% of fluorocarbon wetting agent, 0.5% of dispersing agent, 0.3% of flatting agent and 2% of flatting agent at the rotating speed of 500r/min, then adjusting the rotating speed to 2000-2500 r/min, then dispersing at a high speed for 30 minutes, adjusting the rotating speed to 1500r/min, then adding 5% of film forming auxiliary agent and 17.3% of deionized water, stirring for 10-15 minutes, and finally adding thickener to adjust the viscosity to a proper viscosity. The film forming auxiliary agent comprises 2% of DPM and 3% of DPNB, the thickener comprises 0.4% of thickener WT-108 and 0.5% of thickener U-300, and the matting agent is a mixture of 1% of fumed silica and 1% of micro wax powder.

Test group three

The preparation process of the finishing paint comprises the following steps of adding 77% of emulsion A (the curing amount is 42+/-1%, the main component is modified acrylic acid polymer, and the MFT is 20 ℃) in chemical production of Jiafeng in a dispersing cylinder, sequentially adding 0.3% of defoamer, 0.1% of PH regulator, 0.5% of organosilicon wetting agent, 0.1% of fluorocarbon wetting agent, 0.5% of dispersing agent, 0.3% of flatting agent and 2% of flatting agent at the rotating speed of 500r/min, then adjusting the rotating speed to 2000-2500 r/min, then dispersing at a high speed for 30 minutes, adjusting the rotating speed to 1500r/min, then adding 5% of film forming auxiliary agent and 13.3% of deionized water, stirring for 10-15 minutes, and finally adding thickener to adjust the viscosity to a proper viscosity. The film forming auxiliary agent comprises 2% of DPM and 3% of DPNB, the thickener comprises 0.4% of thickener WT-108 and 0.5% of thickener U-300, and the matting agent is a mixture of 1% of fumed silica and 1% of micro wax powder.

Comparative group one

The preparation process of the finishing paint comprises the following steps of adding 75% of emulsion B (the curing amount is 42+/-1%, the main component is modified acrylic acid polymer, and the MFT is 30 ℃) in a dispersing cylinder, sequentially adding 0.3% of defoaming agent, 0.1% of PH regulator, 0.5% of organosilicon wetting agent, 0.1% of fluorocarbon wetting agent, 0.5% of dispersing agent, 0.3% of leveling agent and 2% of flatting agent at the rotating speed of 500r/min, then adjusting the rotating speed to 2000-2500 r/min, dispersing at a high speed for 30 minutes, adjusting the rotating speed to 1500r/min, then adding 5% of film forming auxiliary agent and 15.3% of deionized water, stirring for 10-15 minutes, and finally adding thickener to adjust to a proper viscosity. The film forming auxiliary agent comprises 2% of DPM and 3% of DPNB, the thickener comprises 0.4% of thickener WT-108 and 0.5% of thickener U-300, and the matting agent is a mixture of 1% of fumed silica and 1% of micro wax powder.

Comparison group two

The preparation process of the finishing paint comprises the following steps of adding 75% of emulsion C (the curing amount is 42+/-1%, the main component is polyurethane modified acrylic polymer, and the MFT is 25 ℃) produced by chemical process in a dispersing cylinder, sequentially adding 0.3% of defoaming agent, 0.1% of PH regulator, 0.5% of organosilicon wetting agent, 0.1% of fluorocarbon wetting agent, 0.5% of dispersing agent, 0.3% of leveling agent and 2% of flatting agent at the rotation speed of 500r/min, then adjusting the rotation speed to 2000-2500 r/min, dispersing at a high speed for 30 minutes, adjusting the rotation speed to 1500r/min, then adding 5% of film forming auxiliary agent and 15.3% of deionized water, stirring for 10-15 minutes, and finally adding thickener to adjust to proper viscosity. The film forming auxiliary agent comprises 2% of DPM and 3% of DPNB, the thickener comprises 0.4% of thickener WT-108 and 0.5% of thickener U-300, and the matting agent is a mixture of 1% of fumed silica and 1% of micro wax powder.

Comparative group three

The preparation process of the finishing paint comprises the following steps of adding 75% of emulsion D (the curing amount is 42+/-1%, the main component is modified acrylic acid polymer, and the MFT is 30 ℃) produced by chemical process in a dispersing cylinder, sequentially adding 0.3% of defoaming agent, 0.1% of PH regulator, 0.5% of organosilicon wetting agent and 0.1% of fluorocarbon wetting agent, 0.5% of dispersing agent, 0.3% of leveling agent and 2% of flatting agent at the rotation speed of 500r/min, then adjusting the rotation speed to 2000-2500 r/min, dispersing at a high speed for 30 minutes, adjusting the rotation speed to 1500r/min, then adding 5% of film forming auxiliary agent and 15.3% of deionized water, stirring for 10-15 minutes, and finally adding thickener to adjust to proper viscosity. The film forming auxiliary agent comprises 2% of DPM and 3% of DPNB, the thickener comprises 0.4% of thickener WT-108 and 0.5% of thickener U-300, and the matting agent is a mixture of 1% of fumed silica and 1% of micro wax powder.

Comparative group four

The preparation process of the finishing paint comprises the following steps of adding 75% of emulsion A (the curing amount is 42+/-1%, the main component is modified acrylic acid polymer, and the MFT is 20 ℃) in a dispersing cylinder, sequentially adding 0.3% of defoamer, 0.1% of PH regulator, 0.6% of organosilicon wetting agent, 0.5% of dispersing agent, 0.3% of flatting agent and 2% of flatting agent at the rotating speed of 500r/min, then adjusting the rotating speed to 2000-2500 r/min, dispersing at a high speed for 30 minutes, adjusting the rotating speed to 1500r/min, then adding 5% of film forming auxiliary agent and 15.3% of deionized water, stirring for 10-15 minutes, and finally adding thickener to adjust to a proper viscosity. The film forming auxiliary agent comprises 2% of DPM and 3% of DPNB, the thickener comprises 0.4% of thickener WT-108 and 0.5% of thickener U-300, and the matting agent is a mixture of 1% of fumed silica and 1% of micro wax powder.

Comparative group five

The preparation process of the finishing paint comprises the following steps of adding 75% of emulsion A (the curing amount is 42+/-1%, the main component is modified acrylic acid polymer, and the MFT is 20 ℃) in chemical production of Jiafeng in a dispersing cylinder, sequentially adding 0.3% of defoamer, 0.1% of PH regulator, 0.3% of organosilicon wetting agent, 0.3% of fluorocarbon wetting agent, 0.5% of dispersing agent, 0.3% of flatting agent and 2% of flatting agent at the rotating speed of 500r/min, then adjusting the rotating speed to 2000-2500 r/min, then dispersing at a high speed for 30 minutes, adjusting the rotating speed to 1500r/min, then adding 5% of film forming auxiliary agent and 15.3% of deionized water, stirring for 10-15 minutes, and finally adding thickener to adjust the viscosity to a proper viscosity. The film forming auxiliary agent comprises 2% of DPM and 3% of DPNB, the thickener comprises 0.4% of thickener WT-108 and 0.5% of thickener U-300, and the matting agent is a mixture of 1% of fumed silica and 1% of micro wax powder.

Table one specific Components of test groups one to three and comparative groups one to five

And spraying the prepared finish paint on the outer surface of the polyurethane model, and observing and comparing the wettability, adhesive force, scratch resistance and storage stability of various finish paints on the surface of the model.

Comparison of test results of the respective test groups and the comparison group

(Remark: adhesion: 1 means best, 5 means worst)

As can be seen from the results of Table II, the top-coat paint obtained by the preparation process of this example has good adhesion to the surface layer of the polyurethane model by using emulsion A, excellent scratch resistance, stable wax in storage state, no floating out, good wettability, and no pinholes on the paint surface (as can be seen from comparison of test group one to three and comparison group one to three). And according to the attached figures 1 and 2, the attached figure 1 shows the spraying effect of the test groups one to three, and the surface is free of pinholes, so that the fluorocarbon wetting agent has a good effect on improving the spreading of a substrate which is difficult to wet. Fig. 2 shows the spray effect of the comparison groups four and five, and pinholes appear on the surface, which indicates that the dosage of the fluorocarbon wetting agent is not too high.

Pinholes appear during spraying, not only in relation to the surface tension of the substrate, but also in relation to the surface tension of the top coat and whether the wetting agent used therein is capable of spreading rapidly on the substrate. When spraying, when large liquid drops are atomized into small liquid drops, the surface area of the liquid is increased, the surface tension of the liquid has a dynamic balance process, the shorter the time from micelle formed in the liquid drops to moving to the surface of the liquid is, the faster the dynamic surface balance is, the better the paint spreads on a base material, if the time required is more, the dynamic surface balance is too slow, and the phenomenon in the figure 2 easily occurs.

Therefore, the emulsion A with excellent adhesive force on the polyurethane substrate is selected, the conventional organic silicon wetting agent and a proper amount of fluorocarbon wetting agent are used as the wetting agent, and the fumed silica is adopted as the matting agent to be matched with the micro wax powder, so that the prepared finish paint with excellent adhesive force, excellent scratch resistance and good wettability on the surface of the model can meet the requirements of a high-end model.

Example two

In the embodiment, on the basis of the first test group, the scratch resistance and the paint hand feeling of the finish paint are continuously tested. The embodiment provides another preparation process of the finish paint, which comprises the following steps:

Firstly, adding emulsion into a dispersing cylinder, then sequentially adding a defoaming agent, a PH regulator, a wetting agent, a dispersing agent, a leveling agent, a handfeel agent and a matting agent at a rotating speed of 500r/min, and then adjusting the rotating speed to 2000-2500 r/min and then dispersing at a high speed for 30 minutes;

and thirdly, adding a thickening agent to adjust the viscosity to be proper.

The beneficial effects of the topcoat prepared by the topcoat preparation process of this example are further illustrated by test set four and several comparative sets.

Test group four

The preparation process of the finishing paint comprises the following steps of adding 75% of emulsion A (the curing amount is 42+/-1%, the main component is modified acrylic acid polymer, and the MFT is 20 ℃) in chemical production of Jiafeng in a dispersing cylinder, sequentially adding 0.3% of defoaming agent, 0.1% of PH regulator, 0.5% of organosilicon wetting agent, 0.1% of fluorocarbon wetting agent, 0.5% of dispersing agent, 0.3% of leveling agent, 3.5% of handfeel agent and 2% of matting agent at the rotating speed of 500r/min, dispersing at a high speed for 30 minutes after the rotating speed is adjusted to 2000-2500 r/min, adding 5% of film forming additive and 11.8% of deionized water after the rotating speed is adjusted to 1500r/min, stirring for 10-15 minutes, and finally adding thickener to adjust to proper viscosity. The film forming auxiliary agent comprises 2% of DPM and 3% of DPNB, the thickener comprises 0.4% of thickener WT-108 and 0.5% of thickener U-300, the delustrant comprises 1% of fumed silica and 1% of micro wax powder, and the handfeel agent comprises 3% of wax emulsion A-8711 and 0.5% of organosilicon handfeel agent A-8714.

Comparison group six

The preparation process of the finishing paint comprises the following steps of adding 75% of emulsion A (the curing amount is 42+/-1%, the main component is modified acrylic acid polymer, and the MFT is 20 ℃) in chemical production of Jiafeng in a dispersing cylinder, sequentially adding 0.3% of defoaming agent, 0.1% of PH regulator, 0.5% of organosilicon wetting agent, 0.1% of fluorocarbon wetting agent, 0.5% of dispersing agent, 0.3% of leveling agent, 3.5% of handfeel agent and 2% of matting agent at the rotating speed of 500r/min, dispersing at a high speed for 30 minutes after the rotating speed is adjusted to 2000-2500 r/min, adding 5% of film forming additive and 11.8% of deionized water after the rotating speed is adjusted to 1500r/min, stirring for 10-15 minutes, and finally adding thickener to adjust to proper viscosity. The film forming auxiliary agent comprises 2% of DPM and 3% of DPNB, the thickener comprises 0.4% of thickener WT-108 and 0.5% of thickener U-300, the delustrant comprises 1% of fumed silica and 1% of micro wax powder, and the handfeel agent comprises 3% of wax emulsion A-8711 and 0.5% of macromolecular organic silicon handfeel agent DC-51.

Comparative group seven

The preparation process of the finishing paint comprises the following steps of adding 75% of emulsion A (the curing amount is 42+/-1%, the main component is modified acrylic acid polymer, and the MFT is 20 ℃) in chemical production of Jiafeng in a dispersing cylinder, sequentially adding 0.3% of defoaming agent, 0.1% of PH regulator, 0.5% of organosilicon wetting agent, 0.1% of fluorocarbon wetting agent, 0.5% of dispersing agent, 0.3% of leveling agent, 3.5% of handfeel agent and 2% of matting agent at the rotating speed of 500r/min, dispersing at a high speed for 30 minutes after the rotating speed is adjusted to 2000-2500 r/min, adding 5% of film forming additive and 12.3% of deionized water after the rotating speed is adjusted to 1500r/min, stirring for 10-15 minutes, and finally adding thickener to adjust to proper viscosity. The film forming auxiliary agent comprises 2% of DPM and 3% of DPNB, the thickener comprises 0.4% of thickener WT-108 and 0.5% of thickener U-300, the delustrant comprises 1% of fumed silica and 1% of micro wax powder, and the handfeel agent comprises 3% of wax emulsion A-8711.

Comparison group eight

The preparation process of the finishing paint comprises the following steps of adding 75% of emulsion A (the curing amount is 42+/-1%, the main component is modified acrylic acid polymer, and the MFT is 20 ℃) in chemical production of Jiafeng in a dispersing cylinder, sequentially adding 0.3% of defoaming agent, 0.1% of PH regulator, 0.5% of organosilicon wetting agent, 0.1% of fluorocarbon wetting agent, 0.5% of dispersing agent, 0.3% of leveling agent, 3.5% of handfeel agent and 2% of matting agent at the rotating speed of 500r/min, dispersing at a high speed for 30 minutes after the rotating speed is adjusted to 2000-2500 r/min, adding 5% of film forming additive and 11.8% of deionized water after the rotating speed is adjusted to 1500r/min, stirring for 10-15 minutes, and finally adding thickener to adjust to proper viscosity. The film forming auxiliary agent comprises 2% of DPM and 3% of DPNB, the thickener comprises 0.4% of thickener WT-108 and 0.5% of thickener U-300, the matting agent is 2% of fumed silica, and the handfeel agent is 3% of wax emulsion A-8711 and 0.5% of organosilicon handfeel agent A-8714.

Comparison group nine

The preparation process of the finishing paint comprises the following steps of adding 75% of emulsion A (the curing amount is 42+/-1%, the main component is modified acrylic acid polymer, and the MFT is 20 ℃) in chemical production of Jiafeng in a dispersing cylinder, sequentially adding 0.3% of defoaming agent, 0.1% of PH regulator, 0.5% of organosilicon wetting agent, 0.1% of fluorocarbon wetting agent, 0.5% of dispersing agent, 0.3% of leveling agent, 3.5% of handfeel agent and 2% of matting agent at the rotating speed of 500r/min, dispersing at a high speed for 30 minutes after the rotating speed is adjusted to 2000-2500 r/min, adding 5% of film forming additive and 11.8% of deionized water after the rotating speed is adjusted to 1500r/min, stirring for 10-15 minutes, and finally adding thickener to adjust to proper viscosity. The film forming auxiliary agent comprises 2% of DPM and 3% of DPNB, the thickener comprises 0.4% of thickener WT-108 and 0.5% of thickener U-300, the matting agent is 2% of fumed silica, and the handfeel agent is 3% of wax emulsion A-8711 and 0.5% of macromolecular organic silicon handfeel agent DC-51.

Comparative group ten

The preparation process of the finishing paint comprises the following steps of adding 75% of emulsion A (the curing amount is 42+/-1%, the main component is modified acrylic acid polymer, and the MFT is 20 ℃) in chemical production of Jiafeng in a dispersing cylinder, sequentially adding 0.3% of defoaming agent, 0.1% of PH regulator, 0.5% of organosilicon wetting agent, 0.1% of fluorocarbon wetting agent, 0.5% of dispersing agent, 0.3% of leveling agent, 3.5% of handfeel agent and 2% of matting agent at the rotating speed of 500r/min, dispersing at a high speed for 30 minutes after the rotating speed is adjusted to 2000-2500 r/min, adding 5% of film forming additive and 11.8% of deionized water after the rotating speed is adjusted to 1500r/min, stirring for 10-15 minutes, and finally adding thickener to adjust to proper viscosity. The film forming auxiliary agent comprises 2% of DPM and 3% of DPNB, the thickener comprises 0.4% of thickener WT-108 and 0.5% of thickener U-300, the matting agent is 2% of fumed silica, and the handfeel agent is 3% of wax emulsion A-8711.

Specific composition of table three test group four and comparison groups six to ten

And spraying the finish paint prepared by each test group and each comparison group on the outer surface of the polyurethane model, and observing and comparing the scratch resistance and hand feeling of various finish paints on the surface of the model.

Scratch resistance and hand feel performance of the paint surface of Table IV

Group of	Scratch resistance and hand feel performance of painted surfaces
		Test group four	The paint film is not broken, has bright marks and good hand feeling
Comparison group six	The paint film sprayed with oil shrink is not broken, has bright marks and good hand feeling
		Comparative group seven	The paint film is not broken, has bright marks and has common hand feeling
Comparison group eight	The paint film is scratched, is lighter than that of a comparison group, and has good hand feeling
		Comparison group nine	The paint film sprayed with oil shrink is scratched, is lighter than that of a comparison group, and has good hand feeling
Comparative group ten	Paint film scratch

From the experimental results of Table four, it can be seen that the finish paint has more excellent scratch resistance than the fumed silica alone by adopting a matting system of micro wax powder and fumed silica, and the wax emulsion has poorer scratch resistance than the micro wax powder (as can be seen from comparison groups seven and ten). The macromolecular organosilicon handfeel agent DC-51 has a certain improvement effect on scratch resistance, but mainly focuses on improving the handfeel, and oil shrinkage is easy to occur when the macromolecular organosilicon handfeel agent DC-51 is not well added (can be seen in comparison groups six and nine). The organosilicon handfeel agent A-8714 is an organosilicon auxiliary agent with better compatibility, is also focused on improving the handfeel of a coating film, and has a certain effect on improving scratch resistance.

Therefore, the finishing paint of the embodiment selects emulsion A with excellent adhesive force sprayed on the polyurethane model, the wetting agent adopts conventional organic silicon wetting agent and proper amount of fluorocarbon wetting agent, the matting agent adopts fumed silica to match micro wax powder and proper handfeel agent, the finishing paint with excellent adhesive force, excellent scratch resistance and good handfeel on the surface of the polyurethane model can be prepared, and the requirements of a high-end model can be met.

While specific embodiments of the invention have been described above, it will be appreciated by those skilled in the art that the specific set of tests described is illustrative only and not intended to limit the scope of the invention, and that equivalent modifications and variations in light of the spirit of the invention will be covered by the claims of the present invention.

Claims

1. The preparation process of the lightweight polyurethane model is characterized in that the polyurethane model comprises a polyurethane surface layer, a polyurethane foaming inner layer and a finish paint coated on the outer surface of the polyurethane surface layer;

The finishing paint comprises 75+/-2% of emulsion, 0.3+/-0.1% of defoamer, 0.1% of PH regulator, 0.5-0.6% of wetting agent, 0.5+/-0.1% of dispersing agent, 0.3+/-0.05% of leveling agent, 2+/-0.2% of flatting agent, 5+/-1% of film forming auxiliary agent, 0.9% of thickening agent and 11.8-17.3% of deionized water, wherein emulsion A produced by Jiafeng chemical industry is adopted as the emulsion, the main component of the emulsion A is modified acrylic polymer, the curing amount is 42+/-1%, the minimum film forming temperature is 20 ℃, the flatting agent comprises fumed silica and micro wax powder, the proportion of the fumed silica to the micro wax powder is 1:1, and the wetting agent is a mixture of 0.5% of organic silicon wetting agent and 0.1% fluorocarbon wetting agent.

2. The process for preparing a lightweight polyurethane model as set forth in claim 1, wherein the polyurethane surface layer is formed by reacting polyether polyol with polyisocyanate, and the polyurethane foam inner layer is formed by reacting polyether polyol, polyisocyanate, foaming agent and catalyst.

3. The process for preparing a lightweight polyurethane model as claimed in claim 2, wherein the catalyst is an organic amine catalyst or an organometallic compound catalyst.

4. The process for preparing the lightweight polyurethane model according to claim 1, wherein the finishing paint further comprises 3-3.5% of a handfeel agent, and the handfeel agent is a mixture of wax emulsion and organosilicon handfeel agent.

5. The process for preparing a lightweight polyurethane model of claim 1, wherein the film forming aid comprises a mixture of DPM and DPNB.

6. The process for preparing the lightweight polyurethane model according to any one of claims 1 to 5, wherein the process for preparing the finish paint comprises the following steps:

and thirdly, adding a thickening agent to adjust the viscosity to be proper.

7. The process for preparing a lightweight polyurethane model as claimed in claim 6, wherein in the first step, a hand feeling agent is added before a matting agent is added, and the addition sequence of the matting agent is that fumed silica and micro wax powder are sequentially added.