Pearlescent pigment and preparation process thereof

Abstract

The invention discloses a preparation process of pearlescent pigment. The preparation process comprises the following steps: preparing a soluble solid film layer on the surface of a base material; the base material is subjected to vacuum coating treatment, and a pearlized film layer is formed on the surface of the soluble solid film; the base material plated with the pearlized film layer is soaked in a dissolving solution, the soluble solid film layer is dissolved, and the pearlized film layer is peeled off; and cleaning, filtering and drying the peeled pearlescent film layer, and crushing and screening the dried pearlescent material to obtain the pearlescent pigment. The film stripping technology and the vacuum coating technology are combined, after the pearlescent film layer is prepared through the coating technology, the pearlescent film layer is stripped to obtain the high-end pearlescent pigment by adopting the method of dissolving the soluble solid film layer on the bottom layer, the whole process is free of pollution, the components of the pearlescent pigment can be conveniently regulated and controlled, and the pearlescent pigment has a good application prospect. Furthermore, the reflective rate of the pearlescent pigment can be freely adjusted.

Description

Technical Field

[0001] The invention relates to the technical field of pearlescent pigment processing, and in particular to a pearlescent pigment and a preparation process thereof. Background Art

[0002] Pearlescent pigment is an optical effect pigment, which refers to a pigment with pearl luster. Because it often presents a certain metallic luster, it is also called a non-metallic pigment with metallic luster. Compared with other pigments, pearlescent pigments have a special surface structure (lamellar structure) and a high refractive index, which enables them to reflect, refract and scatter light, presenting a soft, deep and sparkling luster effect similar to pearls.

[0003] Currently, common pearlescent pigments are mainly based on glass flakes, natural mica, and synthetic mica. A color layer is prepared on the surface of the substrate by chemical methods to achieve pearlescent effects of different colors. The above preparation method will produce a large amount of sewage, causing certain pollution to the environment. In addition, the pearlescent pigments prepared by traditional chemical methods have fewer color types, and the brightness of the prepared pearlescent coating is not easy to adjust. Summary of the invention

[0004] In order to solve the technical problems existing in the above-mentioned background technology, the present invention provides a pearlescent pigment and a preparation process thereof, which combines the film stripping technology and the vacuum coating technology. After the pearlescent film layer is prepared by the coating process, the pearlescent film layer is stripped by dissolving the bottom soluble solid film layer to obtain the high-end pearlescent pigment. The whole process is pollution-free, and the composition of the pearlescent pigment can be conveniently controlled, thereby realizing the free adjustment of the reflectivity of the pearlescent pigment.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] The first aspect of the present invention provides a process for preparing a pearlescent pigment, comprising:

[0007] preparing a soluble solid film layer on the surface of a substrate;

[0008] The substrate is subjected to vacuum coating treatment to form a pearlescent film layer on the surface of the soluble solid film;

[0009] The substrate coated with the pearlescent film layer is immersed in a dissolving solution, the soluble solid film layer is dissolved, and the pearlescent film layer is peeled off;

[0010] The peeled pearlescent film layer is washed, filtered and dried, and then the dried pearlescent material is crushed and screened to obtain pearlescent pigment.

[0011] Furthermore, the soluble solid film layer is formed by soluble solid organic matter or soluble solid inorganic matter.

[0012] In the present invention, the substrate may be inorganic materials such as stainless steel and glass; or organic film materials such as PET film, polyimide film, PP film, etc.

[0013] In the present invention, there are many choices for the preparation materials of the soluble solid film layer formed on the surface of the substrate, for example, soluble solid organic matter such as sucrose, PVP-K30, PVP-K90, sodium citrate, etc. can be selected; soluble solid inorganic matter such as carbonate compounds, halogen compounds, etc. can also be selected. The preparation methods of the soluble solid film using the above-mentioned different materials include coating and drying method, sputtering coating method, evaporation method and spray drying method, etc. Specifically, the corresponding appropriate method can be selected according to the characteristics of the material to form a soluble solid film on the surface of the substrate. The thickness of the soluble solid film layer formed on the surface of the substrate is 0.5μm-100μm. If the soluble solid film layer is too thin, it will result in incomplete coverage, and if the soluble solid film layer is too thick, it will result in waste of raw materials.

[0014] In the present invention, there is a corresponding relationship between the material of the soluble solid film layer and the solvent type of the dissolving solution, so that the substrate coated with the pearlescent film layer can be immersed in the dissolving solution to dissolve the soluble solid film layer, thereby peeling the pearlescent film layer from the substrate.

[0015] Specifically, the dissolving liquid can be selected from one of water-based dissolving liquid, oil-based dissolving liquid, alcohol dissolving liquid or a mixture of several of them.

[0016] An example of the corresponding relationship between the material of the partially soluble solid film layer and the solvent in the dissolving solution is shown in Table 1.

[0017] Table 1

[0018]

[0019] Furthermore, the substrate coated with the pearlescent film layer is immersed in a dissolving solution and ultrasonically treated.

[0020] In order to dissolve the soluble solid film layer quickly and thoroughly, the substrate coated with the pearlescent film layer is placed in an ultrasonic cleaning tank filled with a dissolving solution, and the soluble solid film layer in the middle layer is accelerated to dissolve by means of ultrasonic treatment.

[0021] Furthermore, in the present invention, the pearlescent film layer is prepared by vacuum coating technology, and the pearlescent pigment is obtained by subsequent peeling. In the process of producing the pearlescent pigment, no pollution and harmful substances will be generated. Two types of pearlescent pigments can be produced by the process of the present invention. One of them is a pearlescent film layer structure with a metal layer. Specifically, the pearlescent film layer includes a metal layer, and one or both sides of the metal layer are formed with one or more layers of oxide or nitride, wherein the thickness of the metal layer is above 50nm, and the thickness of the oxide layer or nitride layer can be adjusted according to the actual effect required. When one or more layers of oxide or nitride are formed on both sides of the metal layer, the pearlescent pigment of this type of structure has high brightness and bright colors. By adjusting, a color-changing color effect can be obtained, or it can be a single color; when one or more layers of oxide or nitride are formed only on one side of the metal layer, the color of the pearlescent pigment of this structure is elegant and does not lose its luster.

[0022] The other is a pearlescent film structure without a metal layer. The structure is composed of one or more layers of oxide or nitride. The pearlescent pigment obtained by this structure has a certain light transmittance, and the thickness of the oxide layer or nitride layer can be adjusted according to the actual effect required.

[0023] Specifically, the structure of the pearlescent film layer prepared by vacuum coating technology is as follows:

[0024] 1. There is a metal layer in the middle, and one or more layers of oxide or nitride are distributed on the upper and lower sides of the metal layer.

[0025] 2. The metal layer is used as the bottom layer, and one or more layers of oxide or nitride are distributed on the upper side of the metal layer.

[0026] 3. The bottom layer is one or more layers of oxide or nitride, and a metal layer is distributed on the upper side of the bottom layer.

[0027] 4. Consists of one or more layers of oxide or nitride.

[0028] Specifically, the metal layer is a metal film layer or an alloy film layer formed by vacuum coating, and the material of the metal film layer or the alloy film layer includes one or more of stainless steel, titanium, aluminum, copper, chromium, and niobium.

[0029] The oxide or nitride is an oxide or nitride of silicon, aluminum, titanium, niobium or iron.

[0030] By using different metal layers, or by co-sputtering two or more different metals, and by adjusting the content of different metals in the film layer, the reflectivity of the film layer is adjusted, thereby affecting the brightness of the pearlescent pigment. The brightness of the pearlescent pigment prepared by the present invention can be adjusted within a certain range through the process, and the maximum brightness can reach more than 90%.

[0031] Furthermore, the vacuum coating process includes a PVD film forming process or a CVD film forming process.

[0032] The PVD film forming process is a physical process that uses physical methods to vaporize materials into atoms, molecules or partially ionize them into ions, and deposits thin film materials with special functions on the surface of the substrate material through a low-pressure gas (or plasma) process.

[0033] The CVD film forming process is a chemical reaction process that heats one or more gases (called precursors) to decompose them, produce reaction products, and deposit them on the semiconductor surface to form the desired thin film.

[0034] The second aspect of the present invention provides a pearlescent pigment, which is prepared by the above-mentioned preparation process. By changing the process conditions and optimizing the materials, the reflectivity of the prepared pearlescent pigment can be adjusted, and the maximum reflectivity can reach more than 90%.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] In the present invention, the film stripping technology and the vacuum coating technology are combined for the preparation of pearlescent pigments. First, a soluble solid material is formed into a thin film on a substrate, and then a pearlescent film layer is coated on the soluble solid film layer by using the vacuum coating technology. Finally, the substrate coated with the pearlescent film layer is immersed in a dissolving liquid, and after the soluble solid film layer is dissolved, the pearlescent film layer is stripped to obtain a high-end pearlescent pigment. The pigment production process does not generate pollution and is not restricted by the mica substrate. The composition of the pearlescent pigment can be conveniently regulated, thereby realizing free adjustment of the reflectivity of the pearlescent pigment. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0038] Figure 1 This is a physical picture of the PVPK30 coating formed on the surface of the substrate in Example 2;

[0039] Figure 2 This is a physical picture of the pearlescent film layer formed by vacuum coating on the substrate in Example 2;

[0040] Figure 3 This is a physical picture of the dissolution process of the PVPK30 coating on the substrate in Example 2;

[0041] Figure 4 This is a physical picture of the wet pearlescent pigment peeled off in Example 2;

[0042] Figure 5 This is a physical picture of the pearlescent pigment finally obtained in Example 2. DETAILED DESCRIPTION

[0043] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. 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.

[0044] Example 1

[0045] The preparation process of pearlescent pigment is as follows:

[0046] First, clean the substrate to remove the oil, dirt and dust on the substrate;

[0047] Dissolve sucrose in pure water at a mass ratio of 10% to obtain a sucrose solution, and then use a coating process to evenly coat the sucrose solution on a stainless steel substrate and dry it;

[0048] Place the dried substrate into the vacuum coating equipment, close the chamber door and start vacuuming. Wait until the vacuum reaches 1×10 -2 After 100V, 200sccm of argon gas is introduced at a pressure of about 0.3Pa to prepare a 200nm silicon oxide layer, and then 200sccm of argon gas is introduced at a pressure of about 0.3Pa to prepare a 300nm titanium oxide layer, and then 150sccm of argon gas is introduced, and a bias voltage of 100V is turned on at a pressure of about 0.25Pa to prepare a 300nm Ti metal layer; then 200sccm of argon gas is introduced at a pressure of about 0.3Pa to prepare a 300nm titanium oxide layer; finally, 200sccm of argon gas is introduced at a pressure of about 0.3Pa to prepare a 200nm silicon oxide layer; the titanium oxide layer and the silicon oxide layer on both sides of the Ti metal layer are symmetrically distributed; finally, the coating process of the pearlescent film is completed;

[0049] After the pearlescent film coating process is completed, the substrate is taken out and placed in an ultrasonic cleaning tank filled with pure water to dissolve the sucrose coating and peel off the pearlescent film. The peeled pearlescent film is cleaned and filtered to obtain a wet pearlescent pigment material. The wet pearlescent pigment is dried, crushed and sieved to obtain a pearlescent pigment with a size of 50-100 μm.

[0050] Example 2

[0051] The preparation process of pearlescent pigment is as follows:

[0052] First, clean the substrate to remove the oil, dirt and dust on the substrate;

[0053] PVPK30 was dissolved in pure water at a mass ratio of 5% to obtain a PVPK30 solution, and then the PVPK30 solution was evenly coated on the stainless steel substrate using a coating process and dried. Figure 1 ;

[0054] Place the dried substrate into the vacuum coating equipment, close the chamber door and start vacuuming. Wait until the vacuum reaches 1×10 -2 After 100V, argon gas is introduced at 200 sccm and the pressure is about 0.3Pa to prepare a 200nm silicon oxide layer. Then, argon gas is introduced at 200 sccm and the pressure is about 0.3Pa to prepare a 300nm titanium oxide layer. Then, argon gas is introduced at 150 sccm and the bias voltage of 100V is turned on and the pressure is about 0.25Pa to prepare a 300nm Ti metal layer. Then, argon gas is introduced at 200 sccm and the pressure is about 0.3Pa to prepare a 300nm titanium oxide layer. Finally, argon gas is introduced at 200 sccm and the pressure is about 0.3Pa to prepare a 200nm silicon oxide layer. The titanium oxide layer and silicon oxide layer on both sides of the Ti metal layer are symmetrically distributed. Finally, the coating process of the pearlescent film is completed. See details. Figure 2 ;

[0055] After the pearlescent film coating process is completed, the substrate is taken out and placed in an ultrasonic cleaning tank filled with pure water to dissolve the PVPK30 coating and peel off the pearlescent film. Figure 3 This is a real picture of the substrate during the peeling process. The pearlescent film layer after peeling is washed and filtered to obtain the wet pearlescent pigment material. For details, see Figure 4 The wet pearlescent pigment is dried, crushed and sieved to obtain pearlescent pigment with a size of 50-100 μm. Figure 5 .

[0056] Example 3

[0057] The preparation process of pearlescent pigment is as follows:

[0058] First, clean the substrate to remove the oil, dirt and dust on the substrate;

[0059] Dissolving sodium citrate in pure water at a mass ratio of 20% to obtain a sodium citrate solution, and then using a coating process to evenly coat the sodium citrate solution on a stainless steel substrate and drying it;

[0060] Place the dried substrate into the vacuum coating equipment, close the chamber door and start vacuuming. Wait until the vacuum reaches 1×10 -2After 100V, 200sccm of argon gas is introduced at a pressure of about 0.3Pa to prepare a 200nm silicon oxide layer, and then 200sccm of argon gas is introduced at a pressure of about 0.3Pa to prepare a 300nm titanium oxide layer, and then 150sccm of argon gas is introduced, and a bias voltage of 100V is turned on at a pressure of about 0.25Pa to prepare a 300nm Ti metal layer; then 200sccm of argon gas is introduced at a pressure of about 0.3Pa to prepare a 300nm titanium oxide layer; finally, 200sccm of argon gas is introduced at a pressure of about 0.3Pa to prepare a 200nm silicon oxide layer; the titanium oxide layer and the silicon oxide layer on both sides of the Ti metal layer are symmetrically distributed; finally, the coating process of the pearlescent film is completed;

[0061] After the pearlescent film coating process is completed, the substrate is taken out and placed in an ultrasonic cleaning tank filled with pure water to dissolve the sodium citrate coating and peel off the pearlescent film. The peeled pearlescent film is cleaned and filtered to obtain a wet pearlescent pigment material. The wet pearlescent pigment is dried, crushed and sieved to obtain a pearlescent pigment with a size of 50-100 μm.

[0062] Example 4

[0063] The preparation process of pearlescent pigment is as follows:

[0064] First, clean the substrate to remove the oil, dirt and dust on the substrate;

[0065] The substrate is placed in a vacuum coating device, and a layer of NaCl coating with a thickness of about 1 μm is coated on the stainless steel substrate using a sputtering method;

[0066] Place the dried substrate into the vacuum coating equipment, close the chamber door and start vacuuming. Wait until the vacuum reaches 1×10 -2 After 100V, 200sccm of argon gas is introduced at a pressure of about 0.3Pa to prepare a 200nm silicon oxide layer, and then 200sccm of argon gas is introduced at a pressure of about 0.3Pa to prepare a 300nm titanium oxide layer, and then 150sccm of argon gas is introduced, and a bias voltage of 100V is turned on at a pressure of about 0.25Pa to prepare a 300nm Ti metal layer; then 200sccm of argon gas is introduced at a pressure of about 0.3Pa to prepare a 300nm titanium oxide layer; finally, 200sccm of argon gas is introduced at a pressure of about 0.3Pa to prepare a 200nm silicon oxide layer; the titanium oxide layer and the silicon oxide layer on both sides of the Ti metal layer are symmetrically distributed; finally, the coating process of the pearlescent film is completed;

[0067] After the pearlescent film coating process is completed, the substrate is taken out and placed in an ultrasonic cleaning tank filled with pure water to dissolve the NaCl coating and peel off the pearlescent film. The peeled pearlescent film is cleaned and filtered to obtain a wet pearlescent pigment material. The wet pearlescent pigment is dried, crushed and sieved to obtain a pearlescent pigment with a size of 50-100 μm.

[0068] Example 5

[0069] The preparation process of pearlescent pigment is as follows:

[0070] First, clean the substrate to remove the oil, dirt and dust on the substrate;

[0071] The stainless steel substrate was placed in a vacuum coating device, and a 1 μm sucrose coating was deposited on the substrate using a vacuum evaporation method. The steps for preparing the sucrose coating were as follows: ① Clean the substrate and place it in the device; ② Place a suitable sucrose single crystal in the evaporation crucible; ③ Close the chamber door and evacuate the vacuum chamber; ④ The vacuum of the device reached 4×10 -2 Pa, start running the vacuum evaporation process to obtain a sucrose coating on the substrate;

[0072] Then put the dried substrate into the vacuum coating equipment, close the chamber door and start vacuuming. -2 After 100V, argon gas is introduced at 200sccm and the pressure is about 0.3Pa to prepare a 200nm silicon oxide layer, and then argon gas is introduced at 200sccm and the pressure is about 0.3Pa to prepare a 300nm titanium oxide layer, and then argon gas is introduced at 150sccm and the bias voltage of 100V is turned on and the pressure is about 0.25Pa to prepare a 300nm Ti metal layer; then argon gas is introduced at 200sccm and the pressure is about 0.3Pa to prepare a 300nm titanium oxide layer; finally, argon gas is introduced at 200sccm and the pressure is about 0.3Pa to prepare a 200nm silicon oxide layer; the titanium oxide layer and silicon oxide layer on both sides of the Ti metal layer are symmetrically distributed; finally, the coating process of the pearlescent film is completed;

[0073] After the pearlescent film coating process is completed, the substrate is taken out and placed in an ultrasonic cleaning tank filled with pure water to dissolve the sucrose coating and peel off the pearlescent film. The peeled pearlescent film is cleaned and filtered to obtain a wet pearlescent pigment material. The wet pearlescent pigment is dried, crushed and sieved to obtain a pearlescent pigment with a size of 50-100 μm.

[0074] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A process for preparing pearlescent pigment, characterized in that: include: preparing a soluble solid film layer on the surface of a substrate; The substrate is subjected to vacuum coating treatment to form a pearlescent film layer on the surface of the soluble solid film; The substrate coated with the pearlescent film layer is immersed in a dissolving solution, the soluble solid film layer is dissolved, and the pearlescent film layer is peeled off; The peeled pearlescent film layer is washed, filtered and dried, and then the dried pearlescent material is crushed and screened to obtain pearlescent pigment.

2. The preparation process of the pearlescent pigment according to claim 1, characterized in that: The soluble solid film layer is formed by soluble solid organic matter or soluble solid inorganic matter.

3. The preparation process of the pearlescent pigment according to claim 2, characterized in that: The soluble solid organic matter includes sucrose, PVP-K30, PVP-K90 or sodium citrate; the soluble solid inorganic matter includes carbonate compounds or halogen compounds.

4. The preparation process of the pearlescent pigment according to claim 2 or 3, characterized in that: The dissolving liquid is one of a water-based dissolving liquid, an oil-based dissolving liquid, and an alcohol-based dissolving liquid, or a mixture of the two or more thereof.

5. The preparation process of pearlescent pigment according to claim 1, characterized in that: The substrate coated with the pearlescent film layer is immersed in a dissolving solution and ultrasonically treated at the same time.

6. The preparation process of pearlescent pigment according to claim 1, characterized in that: The pearlescent film layer includes a metal layer, and one or more layers of oxide or nitride are formed on one side or both sides of the metal layer.

7. The process for preparing pearlescent pigment according to claim 1, characterized in that: The pearlescent film layer is composed of one or more layers of oxide or nitride.

8. The process for preparing the pearlescent pigment according to claim 6, characterized in that: The metal layer is a metal film layer or an alloy film layer formed by vacuum coating, and the material of the metal film layer or the alloy film layer includes one or more of stainless steel, titanium, aluminum, copper, chromium, and niobium.

9. The process for preparing the pearlescent pigment according to claim 6 or 7, characterized in that: The oxide or nitride is an oxide or nitride of silicon, aluminum, titanium, niobium or iron.

10. A pearlescent pigment, characterized in that: It is prepared by the preparation process described in any one of claims 1 to 9.

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