Pearlescent paper structure and manufacturing method thereof

Abstract

The invention discloses a pearlescent paper structure and a manufacturing method thereof. The pearlescent paper structure is provided with a middle layer and a matte layer. The matte layer is arranged on the middle layer, the matte layer is made of a polyolefin material and a filler, and the polyolefin material is formed by reacting a propylene polymer, an ethylene polymer and an initiator. The total weight of the matte layer is 100 weight percent, the content of the propylene polymer is 20 to 65 weight percent, the content of the ethylene polymer is 30 to 75 weight percent, and the content of the filler is 5 to 10 weight percent. The arithmetic mean roughness of the matte layer is 0.5 [mu] m to 1.3 [mu] m. Through selection of materials and adjustment of manufacturing steps, the polyolefin material generates fewer crystal points, so that the pearlescent paper has better printing quality, and the pearlescent paper structure has lower surface roughness.

Description

Technical Field

[0001] The present invention relates to a pearlescent paper structure and a manufacturing method thereof, and particularly to a pearlescent paper structure with low roughness and a manufacturing method thereof. Background Art

[0002] Pearlescent paper belongs to a synthetic paper and is made of petrochemical synthetic resin. Compared with ordinary paper made of wood pulp, pearlescent paper has better water resistance, tear resistance and surface smoothness, but also has a higher density, making it impossible for pearlescent paper to have the advantage of light weight.

[0003] Therefore, some fillers are added to the resin raw material for preparing pearlescent paper. Since the filler is incompatible with the resin raw material, in the uniaxial or biaxial stretching process, the resin raw material will form fine pores around the filler due to stretching, thereby achieving the effect of reducing the density of the pearlescent paper.

[0004] However, the addition of the filler will also form pores on the surface of the pearlescent paper, resulting in an increase in the surface roughness of the pearlescent paper. Moreover, during the production process of the resin raw material, there may sometimes be catalyst residues. In a high-temperature environment, the polymer will continue to polymerize to form over-polymers, resulting in uneven polymerization degrees in various parts of the resin raw material. The part of the over-polymer is prone to form crystal points and reduce the printing efficiency.

[0005] Therefore, how to improve the surface characteristics of pearlescent paper through the improvement of material design to overcome the above-mentioned defects has become one of the important issues to be solved in this field. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to disclose a resin composition, a preparation method thereof and a prepreg sheet in view of the deficiencies of the prior art.

[0007] To solve the above-mentioned technical problem, one of the technical solutions adopted by the present invention is to disclose a pearlescent paper structure. The pearlescent paper structure has an intermediate layer and a matte layer. The matte layer is disposed on the intermediate layer. The material of the matte layer includes a polyolefin material and a filler. The polyolefin material is formed by the reaction of a propylene polymer, an ethylene polymer and an initiator. Based on the total weight of the matte layer being 100 weight percentages, the content of the propylene polymer is 20 weight percentages to 65 weight percentages, the content of the ethylene polymer is 30 weight percentages to 75 weight percentages, and the content of the filler is 5 weight percentages to 10 weight percentages. The arithmetic mean roughness of the matte layer is 0.5 micrometers to 1.3 micrometers.

[0008] Furthermore, the content of the initiator in the matte layer is 500 parts per million to 2500 parts per million.

[0009] Further, the initiator is selected from the group consisting of 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, di-tert-butyl peroxide, diisopropyl peroxide, acetyl peroxide, benzoyl peroxide, and ethyl perbenzoate.

[0010] Further, the melting point of the propylene polymer is 155°C to 165°C.

[0011] Further, the melting point of the ethylene polymer is 115°C to 125°C.

[0012] Further, the gloss of the mist layer is 35% to 50%.

[0013] Further, the material of the intermediate layer includes a propylene polymer.

[0014] Further, the pearlescent paper structure includes two mist layers, and the intermediate layer is disposed between the two mist layers.

[0015] To solve the above technical problems, another technical solution adopted by the present invention is to disclose a manufacturing method of a pearlescent paper structure. The manufacturing method of the pearlescent paper structure includes the following steps: preparing an intermediate layer material and a mist layer material, the mist layer material including a propylene polymer, an ethylene polymer, a filler, and an initiator. Using the intermediate layer material and the mist layer material, a co-extrusion process is carried out to obtain a pearlescent paper structure. In the co-extrusion process, the propylene polymer, the ethylene polymer, and the initiator react to form a polyolefin material. The pearlescent paper structure includes an intermediate layer formed by the intermediate layer material and a mist layer formed by the mist layer material, the mist layer being disposed on the intermediate layer, and the arithmetic mean roughness of the mist layer being 0.5 μm to 1.3 μm. Based on the total weight of the mist layer material being 100 weight percentages, the content of the propylene polymer is 20 weight percentages to 65 weight percentages, the content of the ethylene polymer is 30 weight percentages to 75 weight percentages, and the content of the filler is 5 weight percentages to 10 weight percentages.

[0016] Further, in the co-extrusion process, the processing temperature of the mist layer material is 180°C to 210°C.

[0017] Further, in the co-extrusion process, the initiator promotes the degradation reaction of the propylene polymer and promotes the cross-linking reaction of the ethylene polymer, so that the initiator, the propylene polymer, and the ethylene polymer react to generate a polyolefin material.

[0018] Further, the difference in melting point between the propylene polymer and the ethylene polymer is 30°C to 50°C.

[0019] Further, the melting point of the propylene polymer is 155°C to 165°C.

[0020] Furthermore, the melting point of the ethylene polymer is 115°C to 125°C.

[0021] One beneficial effect of the present invention is that the pearlescent paper structure and its manufacturing method provided by the present invention can improve the surface characteristics of the pearlescent paper structure through the technical solutions of "the material of the fog layer includes a polyolefin material and a filler" and "the polyolefin material is formed by the reaction of a propylene polymer, an ethylene polymer, and an initiator".

[0022] To further understand the features and technical content of the present invention, please refer to the following detailed description and drawings of the present invention. However, the provided drawings are only for reference and illustration, and are not used to limit the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a side view schematic diagram of the pearlescent paper structure of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0024] The following are specific embodiments to illustrate the specific implementation manners of the "pearlescent paper structure and its manufacturing method" disclosed by the present invention. Those skilled in the art can understand the advantages and effects of the present invention from the content disclosed in this specification. The present invention can be implemented or applied through other different specific embodiments, and various details in this specification can also be modified and changed based on different viewpoints and applications without departing from the concept of the present invention. Additionally, the drawings of the present invention are only simple schematic illustrations and are not drawn according to actual sizes, hereby stated. The following specific implementation manners will further detail the related technical content of the present invention, but the disclosed content is not used to limit the protection scope of the present invention. In addition, the term "or" used herein should, depending on the actual situation, possibly include any one or a combination of more of the associated listed items.

[0025] To overcome the above problems, the present invention discloses a pearlescent paper structure. Through the selection of materials and the adjustment of manufacturing steps, the pearlescent paper structure of the present invention can have a lower surface roughness. And, through the selection of materials and the adjustment of manufacturing steps, the polyolefin material of the present invention generates fewer crystal points and can have better printing quality.

[0026] The pearlescent paper structure of the present invention includes an intermediate layer and a fog layer, and the fog layer is disposed on the intermediate layer. The fog layer can be selectively disposed on one or both sides of the intermediate layer to form a single-sided or double-sided pearlescent paper structure. If the thickness of the overall pearlescent paper structure is 100%, the thickness of the intermediate layer is 80% to 90%, and the thickness of the fog layer is 5% to 20%.

[0027] The middle layer is the main supporting structure of the pearlescent paper structure, endowing the pearlescent paper structure with certain mechanical strength, such as stiffness, to facilitate subsequent processing techniques. Additionally, for ease of use, the middle layer has a low density (less than 0.65 g / cm³), enabling the pearlescent paper structure to have the advantage of light weight, but the present invention is not limited thereto.

[0028] The matte layer endows the pearlescent paper structure with good surface characteristics. Therefore, the matte layer completely covers the surface of the middle layer, preventing the middle layer from being exposed. Specifically, the arithmetic mean roughness of the surface of the matte layer is less than 1.3 µm (preferably 0.5 µm to 1.3 µm), and the glossiness of the surface of the matte layer is less than 50% (preferably 35% to 50%), but the present invention is not limited thereto.

[0029] Please refer to Figure 1 As shown, in an exemplary embodiment, the pearlescent paper structure is a three-layer structure. The pearlescent paper structure includes a middle layer 1 and two matte layers 2. The middle layer 1 is disposed between the two matte layers 2. The two matte layers 2 completely cover the opposite surfaces of the middle layer 1, preventing the middle layer 1 from being exposed. The specific components of the middle layer 1 and the matte layer 2 will be described below.

[0030] The middle layer 1 includes a continuous phase portion 11 and a dispersed phase portion 12. The dispersed phase portion 12 is uniformly dispersed in the continuous phase portion 11. The dispersed phase portion 12 can make the pearlescent paper 1 have a low density to achieve the effect of light weight.

[0031] In a preferred embodiment, the dispersed phase portion 12 is uniformly dispersed in the continuous phase portion 11 in a spherical shape, and the size of the spherical shape is 1 µm to 2 µm. If the size of the dispersed phase portion 12 is too large, the film may break during the stretching process and fail to form a film. If the size of the dispersed phase portion 12 is too small, pores may not be formed during the stretching process, and the expected light weight effect may not be achieved.

[0032] Specifically, the material forming the continuous phase portion 11 is polypropylene, and the polypropylene can be a propylene homopolymer (PP-H), a block propylene copolymer (PP-B), a random propylene copolymer (PP-R), or a mixture thereof. In a preferred embodiment, a propylene homopolymer is selected as the material forming the continuous phase portion 11, and the melting point of the material forming the continuous phase portion 11 is 155°C to 175°C. Preferably, the melting point of the material forming the continuous phase portion 11 is 160°C to 165°C, and the melt flow index (MI) of the material forming the continuous phase portion 11 is 3 g / 10 min to 5 g / 10 min, preferably 3 g / 10 min to 4 g / 10 min.

[0033] Specifically, the material forming the dispersed phase portion 12 can be an organic filler or an inorganic filler. When the dispersed phase portion 12 is an organic filler, the organic filler can be a polyester. For example, the polyester can be polyethylene terephthalate (PET), polybutylene terephthalate (PBT), or a mixture thereof. When the dispersed phase portion 12 is an inorganic filler, the inorganic filler can be selected from the group consisting of titanium dioxide, silica, calcium silicate, and calcium carbonate.

[0034] In a preferred embodiment, the material forming the dispersed phase portion 12 is an inorganic filler. Moreover, the inorganic filler can be a combination of titanium dioxide and calcium carbonate.

[0035] The mist layer 2 is disposed on the intermediate layer 1 and forms a continuous mist layer. The so-called "continuous" means that the mist layer 2 completely covers the intermediate layer 1 to prevent the intermediate layer 1 from contacting the outside. If the mist layer 2 does not completely cover the intermediate layer 1, during subsequent printing processes, the solvent used in the process will penetrate into the fine pores in the intermediate layer 1, causing the dimensional specifications of the pearlescent paper 1 to change and damaging the quality of the pearlescent paper 1 product.

[0036] Moreover, if the mist layer 2 does not completely cover the intermediate layer 1, after long-term use, the organic filler or inorganic filler forming the dispersed phase portion 12 may detach from the continuous phase portion 11, resulting in powdering on the surface of the pearlescent paper structure, causing the surface of the pearlescent paper structure to become rough and the texture to deteriorate.

[0037] The material forming the mist layer 2 includes a polyolefin material and a filler. The polyolefin material serves as the continuous phase in the mist layer 2, and the filler is dispersed in the polyolefin material in a dispersed phase manner. It should be noted that the polyolefin material is formed by reacting a propylene polymer, an ethylene polymer, and an initiator.

[0038] At a certain temperature, the initiator will break its bonds due to high temperature to form free radicals. The free radicals react with the propylene polymer to form macroradicals with free radicals, and the macroradicals with free radicals undergo β-scission reactions, causing the propylene polymer to undergo a degradation reaction.

[0039] On the other hand, also under the action of the initiator, after the free radicals react with the ethylene polymer to form macroradicals with free radicals, two macroradicals with free radicals will join together. That is to say, the ethylene polymer undergoes a crosslinking reaction.

[0040] Macroscopically, the propylene polymer and the ethylene polymer can be mixed with each other in a continuous phase, but microscopically, the propylene polymer and the ethylene polymer are still independent long molecular chains and do not actually merge into one.

[0041] In the present invention, by adding an initiator, a degradation reaction occurs in the propylene polymer and a crosslinking reaction occurs in the ethylene polymer. Moreover, when the degradation reaction of the propylene polymer and the crosslinking reaction of the ethylene polymer occur simultaneously, the macromolecules with free radicals formed by the propylene polymer may also react with the macromolecules with free radicals formed by the ethylene polymer, and then merge into one. That is to say, after adding the initiator, the propylene polymer can further react with the ethylene polymer, and a very complex reaction will occur in this component system at a certain temperature.

[0042] Compared with the polyolefin material obtained by directly mixing the propylene polymer and the ethylene polymer, or the polyolefin material obtained by mixing the propylene polymer, the ethylene polymer and the initiator, the polyolefin material of the present invention can have more uniform properties. And when the polyolefin material of the present invention is used as the material of the fog layer 2, the fog layer can have a lower surface roughness.

[0043] In addition, in order to avoid the generation of crystal points due to uneven molecular weight of the polyolefin material, the present invention further selects specific propylene polymers, ethylene polymers and initiators as raw materials.

[0044] Since a degradation reaction occurs in the propylene polymer and a crosslinking reaction occurs in the ethylene polymer, the present invention controls the molecular chain length of the propylene polymer before the reaction to be higher than that of the ethylene polymer before the reaction. In this way, when the molecular chain length of the propylene polymer after the degradation reaction is close to the molecular chain length of the ethylene polymer after the crosslinking reaction, crystal points can be avoided.

[0045] However, as mentioned above, the reaction of this component system is quite complex, so the characteristics of the propylene polymer and the ethylene polymer before the reaction are described.

[0046] The melting point of the propylene polymer is 155 °C to 165 °C. Specifically, the melting point of the propylene polymer can be 156 °C, 158 °C, 160 °C, 162 °C or 164 °C. The melt index of the propylene polymer is 3 g / 10 min to 5 g / 10 min.

[0047] Specifically, the propylene polymer can be a propylene homopolymer (PP-H), a block propylene copolymer (PP-B), a random propylene copolymer (PP-R) or a mixture thereof. In a preferred embodiment, the propylene polymer is a propylene homopolymer.

[0048] The melting point of the ethylene polymer is 115°C to 125°C. Specifically, the melting point of the propylene polymer can be 116°C, 118°C, 120°C, 122°C, or 124°C. The melt index of the ethylene polymer is 1 g / 10 min to 3 g / 10 min.

[0049] Specifically, the ethylene polymer can be an ethylene homopolymer (PE-H), a block ethylene copolymer (PE-B), a random ethylene copolymer (PE-R), or a mixture thereof. In a preferred embodiment, the ethylene polymer is an ethylene homopolymer.

[0050] Specifically, the initiator can be a peroxide. The initiator is selected from the group consisting of 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, di-tert-butyl peroxide, diisopropyl peroxide, acetyl peroxide, benzoyl peroxide, and ethyl perbenzoate. Preferably, the initiator is 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane or diisopropyl peroxide.

[0051] Based on the total weight of the mist layer 2 being 100 weight percent, the content of the propylene polymer is 20 weight percent to 65 weight percent, for example, 25 weight percent, 30 weight percent, 35 weight percent, 40 weight percent, 45 weight percent, 50 weight percent, 55 weight percent, or 60 weight percent.

[0052] Based on the total weight of the mist layer 2 being 100 weight percent, the content of the ethylene polymer is 30 weight percent to 75 weight percent, for example, 35 weight percent, 40 weight percent, 45 weight percent, 50 weight percent, 55 weight percent, 60 weight percent, 65 weight percent, or 70 weight percent.

[0053] Based on the total weight of the mist layer 2 being 100 weight percent, the content of the filler is 5 weight percent to 10 weight percent, for example, 6 weight percent or 8 weight percent.

[0054] In addition, the content of the initiator in the mist layer is 500 parts per million to 2500 parts per million, for example, 600 parts per million, 800 parts per million, 1000 parts per million, 1200 parts per million, 1400 parts per million, 1600 parts per million, 1800 parts per million, 2000 parts per million, 2200 parts per million, or 2400 parts per million.

[0055] In a preferred embodiment, the addition amount of the ethylene polymer is higher than that of the propylene polymer, so that the ethylene polymer can react with the propylene polymer during the crosslinking reaction to form the polyolefin material of the present invention.

[0056] Specifically, the content of the propylene polymer is 20% to 45% by weight, the content of the ethylene polymer is 50% to 75% by weight, and the content of the filler is 5% to 10% by weight. The content of the initiator in the mist layer 2 is 800 parts per million (ppm) to 2000 ppm.

[0057] In addition to the above components, the material forming the mist layer 2 may further include an antioxidant and a flow aid, but the present invention is not limited thereto.

[0058] The antioxidant may be a hindered phenol antioxidant, a phosphite antioxidant or a combination thereof. The content of the antioxidant in the mist layer 2 is 500 ppm to 3000 ppm. Preferably, the antioxidant is a combination of a hindered phenol antioxidant and a phosphite antioxidant.

[0059] The flow aid may be silicone oil, paraffin wax, silicone compound or a combination thereof. The content of the flow aid in the mist layer 2 is 3000 ppm to 5000 ppm. Preferably, the flow aid is paraffin wax.

[0060] Experimental data

[0061] To confirm that the pearlescent paper structure of the present invention has a lower surface roughness, an intermediate layer material and a mist layer material are formulated according to the components listed in Table 1. The intermediate layer material and the mist layer material are fed into a co-extrusion device, and a composite film (mist layer material / intermediate layer material / mist layer material) is prepared through a co-extrusion process. Then, the composite film is subjected to a stretching process in the machine direction (MD) and the transverse direction (TD) in sequence to obtain the pearlescent paper structures of Examples 1 to 3 and Comparative Example 1, as Figure 1 shown.

[0062] In Examples 1 to 3 and Comparative Example 1, the intermediate layer material is used to form the intermediate layer 1, and the mist layer material is used to form the mist layer 2. Moreover, the intermediate layer 1 is disposed between two mist layers 2. The total thickness of the pearlescent paper structure is 100 microns, wherein the thickness of the intermediate layer is 80 microns, and the thickness of a single mist layer is 10 microns.

[0063] It should be noted that in the co-extrusion process, the intermediate layer material and the mist layer material are extruded at different processing temperatures. Specifically, the intermediate layer material is extruded at a processing temperature of 220°C to 250°C, and the mist layer material is extruded at a processing temperature of 180°C to 250°C. In the co-extrusion process, the propylene polymer, ethylene polymer and initiator in the mist layer material will react to form a polyolefin material.

[0064] In the stretching process, the stretching ratio of the composite film material in the machine direction (MD) is 6 times, and the stretching ratio in the transverse direction (TD) is 8 times. However, the present invention is not limited thereto.

[0065] After forming the pearlescent paper structure, according to the TAPPI T-555 standard test method, an arithmetic mean roughness (Ra) of the matte layer is measured using a roughness measuring instrument (manufacturer: Testing Machines Inc., model: 58-06-00-001). According to the TAPPI T-480 standard test method, the glossiness of the matte layer is measured using a gloss meter (manufacturer: Byk-Gardner GmbH). Then, according to the ASTM D-1003 standard test method, the haze of the matte layer is measured using a desktop haze meter (manufacturer: Tokyo Denshoku, model: TC-HIII). The specific measurement results are listed in Table 2.

[0066] Table 1

[0067]

[0068] Table 2

[0069] Example 1 Example 2 Example 3 Comparative Example 1 Total thickness (μm) 100 100 100 100 Surface roughness (μm) 0.6 0.8 1.1 2.5 Glossiness (%) 37 39 45 21 Haze (%) 72 75 81 66

[0070] According to the results of Table 1 and Table 2, using a polyolefin material (Examples 1 to 3) formed by the reaction of a propylene polymer, an ethylene polymer, and an initiator as the material of the matte layer can make the matte layer have a lower surface roughness, which cannot be achieved by a polyolefin material (Comparative Example 1) that simply mixes a propylene polymer and an ethylene polymer.

[0071] Specifically, the roughness of the matte layer of the present invention can be less than 1.3 microns, preferably 0.5 microns to 1.3 microns. In addition, the pearlescent paper structure of the present invention has the characteristic of low glossiness (less than or equal to 50%).

[0072] In addition to the influence of the material, the processing temperature of coextrusion also affects the surface roughness of the matte layer. When the processing temperature is 180°C to 250°C (Examples 1 to 3), the matte layer can have a surface roughness of 0.5 microns to 1.3 microns. Further, when the processing temperature is 180°C to 210°C (Examples 1 to 2), the matte layer can have a surface roughness of 0.5 microns to 1.0 microns.

[0073] Advantageous Effects of the Examples

[0074] One of the beneficial effects of the present invention is that the pearlescent paper structure and its manufacturing method provided by the present invention can improve the surface characteristics of the pearlescent paper structure through the technical solutions of "the material of the fog layer includes a polyolefin material and a filler" and "the polyolefin material is formed by the reaction of a propylene polymer, an ethylene polymer and an initiator".

[0075] Furthermore, the reaction temperature also affects the properties of the polyolefin material. In order to achieve the property of low surface roughness of the fog layer, the processing temperature of the fog layer material is 180°C to 250°C, preferably 180°C to 210°C.

[0076] The content disclosed above is only the preferred feasible embodiment of the present invention, and does not limit the claims of the present invention. Therefore, all equivalent technical changes made by using the content of the specification and drawings of the present invention are included in the claims of the present invention.

Claims

1. A pearlescent paper structure, characterized in that: The pearlescent paper structure comprises: a middle layer; and a matte layer disposed on the intermediate layer, wherein the material of the matte layer comprises a polyolefin material and a filler, wherein the polyolefin material is formed by reacting a propylene polymer, an ethylene polymer and an initiator; wherein, based on the total weight of the matte layer being 100 weight percent, the content of the propylene polymer is 20 weight percent to 65 weight percent, the content of the ethylene polymer is 30 weight percent to 75 weight percent, and the content of the filler is 5 weight percent to 10 weight percent; Wherein, the arithmetic mean roughness of the matte layer is 0.5 micrometers to 1.3 micrometers.

2. The pearlescent paper structure according to claim 1, characterized in that: The content of the initiator in the matte layer is 500 ppm to 2500 ppm.

3. The pearlescent paper structure according to claim 1, characterized in that: The initiator is selected from the group consisting of 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, di-tert-butyl peroxide, diisopropyl peroxide, acetyl peroxide, benzoyl peroxide and ethyl perbenzoate.

4. The pearlescent paper structure according to claim 1, characterized in that: The propylene polymer has a melting point of 155°C to 165°C.

5. The pearl paper structure according to claim 1, characterized in that: The melting point of the ethylene polymer is 115°C to 125°C.

6. The pearlescent paper structure according to claim 1, characterized in that: The glossiness of the matte layer is 35% to 50%.

7. The pearlescent paper structure according to claim 1, characterized in that: The material of the intermediate layer includes propylene polymer.

8. The pearlescent paper structure according to claim 1, characterized in that: The pearlescent paper structure comprises two matte layers, and the middle layer is arranged between the two matte layers.

9. A method for manufacturing a pearlescent paper structure, characterized in that: The manufacturing method of the pearlescent paper structure comprises: Preparing an intermediate layer material and a matte layer material; wherein the matte layer material comprises a propylene polymer, an ethylene polymer, a filler and an initiator; and The intermediate layer material and the matte layer material are used to perform a co-extrusion process to obtain a pearlescent paper structure; wherein, in the co-extrusion process, the propylene polymer, the ethylene polymer and the initiator react to form a polyolefin material; The pearlescent paper structure includes an intermediate layer formed by the intermediate layer material and a matte layer formed by the matte layer material, the matte layer is arranged on the intermediate layer, and the arithmetic average roughness of the matte layer is 0.5 micrometers to 1.3 micrometers; Wherein, taking the total weight of the matte layer material as 100 weight percent, the content of the propylene polymer is 20 weight percent to 65 weight percent, the content of the ethylene polymer is 30 weight percent to 75 weight percent, and the content of the filler is 5 weight percent to 10 weight percent.

10. The method for manufacturing a pearlescent paper structure according to claim 9, characterized in that: In the co-extrusion process, the processing temperature of the matte layer material is 180° C. to 210° C.

11. The method for manufacturing a pearlescent paper structure according to claim 9, characterized in that: In the co-extrusion process, the initiator causes the propylene polymer to undergo a degradation reaction and causes the ethylene polymer to undergo a cross-linking reaction, so that the initiator, the propylene polymer and the ethylene polymer react to generate a polyolefin material.

12. The method for manufacturing a pearlescent paper structure according to claim 9, characterized in that: The difference in melting points between the propylene polymer and the ethylene polymer is 30°C to 50°C.

13. The method for manufacturing a pearlescent paper structure according to claim 9, characterized in that: The propylene polymer has a melting point of 155°C to 165°C.

14. The method for manufacturing a pearlescent paper structure according to claim 9, characterized in that: The melting point of the ethylene polymer is 115°C to 125°C.

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