Mold release film and manufacturing method thereof

Abstract

The invention relates to a mold release film and a manufacturing method thereof, the mold release film comprises a base material and a surface layer formed on at least one surface of the base material, the base material is polyethylene glycol terephthalate or polyethylene naphthalate, and the surface layer is formed on at least one surface of the base material. The surface layer is basically prepared by mixing unsaturated polyester resin, a high-TG polyester monomer, a curing agent and an organic solvent, and the surface layer is impressed with preset lines through a matte release film and is transferred to the surface of a chip molding compound. The method comprises the following steps: preparing polyester fluid; manufacturing a matte release film; and the manufactured matte release film is impressed to form surface textures, and the mold release film is manufactured. According to the mold release film, surface textures are formed through coining, polyester resin and high-TG polyester are used, the situation that a jig and a mold cavity are polluted due to powder falling during EMC closed surface treatment is avoided, the yield of chip packaging products is increased, and meanwhile the chip surface achieves the effects of abrasion resistance, fast heat dissipation, chemical resistance, heat resistance and the like.

Description

Technical Field

[0001] The invention relates to the technical field of surface treatment of semiconductor packaging materials, and in particular to a mold release film and a manufacturing method thereof, and a surface treatment process of a chip plastic packaging material. Background Art

[0002] Mold release film is an essential material used in the chip packaging process, whether it is transfer molding or compression molding, to improve the surface condition of the molded product and protect the mold.

[0003] Currently, the existing mold release films are basically Japanese materials, which are a layer of fluorine-containing material coated on the surface of PET (PEN) and contain large-particle titanium dioxide. The cost is high, and the titanium dioxide is easy to fall off during use, causing pollution. The mold must be cleaned after each use, which is troublesome to maintain and easily causes scrapping.

[0004] In summary, there is an urgent need for a mold release film with a coating that does not shed powder and a manufacturing method thereof to solve the above-mentioned problems. Summary of the invention

[0005] In view of this, a mold release film with a coating that does not shed powder and a manufacturing method thereof and a surface treatment process for a chip plastic packaging material are provided.

[0006] A mold release film comprises a substrate and a surface layer formed on at least one side of the substrate, wherein the substrate is polyethylene terephthalate or polyethylene naphthalate, and the surface layer is basically made of a mixture of unsaturated polyester resin, high TG polyester monomer, curing agent, and organic solvent. At least one of the surface layers is embossed with a predetermined pattern through a matte release film for transfer to the surface of a chip plastic packaging material.

[0007] Preferably, the mass ratio of the components of the surface layer is as follows: 15-25 parts of unsaturated polyester resin, 5-15 parts of high TG polyester monomer, 50-70 parts of organic solvent, and 1-5 parts of curing agent.

[0008] Preferably, a polyurethane coating is formed on one side of the substrate, and the mass ratio of each component in the polyurethane coating is as follows: 10-20 parts of polyurethane, 5-15 parts of high TG polyester, 5-15 parts of titanium dioxide, 1-10 parts of curing agent, and 40-80 parts of solvent; the surface layer is formed on the other surface of the substrate opposite to the polyurethane coating.

[0009] Preferably, the polyurethane coating is prepared by mixing the components uniformly, and then precisely coating, drying, and rolling up to form a matte film structure; the roughness Ra of the matte film structure is controlled between 0.1-2, and the roughness Rz is controlled between 3-15.

[0010] Preferably, a matte film is formed on one surface of the substrate, and the surface layer is obtained by evenly coating an unsaturated polyester mixture fluid on the bright surface of the matte film of the substrate, and imprinting the texture on the matte film onto the fluid through a laminating roller to form an irregular surface texture, so as to produce a double-sided matte mold release film.

[0011] Preferably, the unsaturated polyester resin and the high TG polyester resin in the surface layer are mixed in a mass ratio of 2-2.5:1-1.5; the curing agent is an isocyanate or epoxy resin crosslinking agent; the organic solvent is toluene, ethyl acetate, or a solvent formed by mixing toluene or ethyl acetate in a predetermined ratio.

[0012] A method for making the mold release film as described above comprises the following steps: After adding unsaturated polyester resin to an organic solvent for a predetermined time, a high TG polyester monomer is added and stirred for a predetermined time to obtain a polyester fluid; then, an organic solvent is added to the polyester fluid for stirring, and then a curing agent is added and stirred to obtain a polyester resin fluid; Polyethylene terephthalate or polyethylene naphthalate is selected as the substrate, and the substrate is divided into two parts, the first part is a mold release film substrate, and the second part is a matte release film substrate, and a layer of polyurethane coating is coated on the surface of the matte release film substrate to make a matte release film; The polyester resin fluid is coated on at least one surface of the mold release film substrate, and the texture on the matte release film is embossed on the polyester resin fluid to form an irregular surface texture to produce the mold release film.

[0013] Specifically, a polyurethane coating is formed on one surface of the mold release film substrate and is made into a matte film structure, and the other surface is embossed with the texture on the matte release film onto the polyester resin fluid through a bonding roller to form a double-sided matte mold release film; the matte film structure on either side of the mold release film is basically the same as the matte structure of the matte release film.

[0014] Preferably, the specific process for obtaining the polyester resin fluid is as follows: after adding the unsaturated polyester resin to an organic solvent for dispersion treatment for 15 to 20 minutes, adding a high TG polyester monomer, stirring and reacting at 75°C for 8 hours to obtain a high temperature resistant polyester fluid; then adding the organic solvent into the polyester fluid and stirring for 30 to 40 minutes, then adding a curing agent and continuing to stir for 15 to 20 minutes to obtain a polyester resin fluid.

[0015] And, a chip molding material surface treatment process, which comprises the following steps: The mold release film is made by adopting the method for making the mold release film as described above; placing a potting resin encapsulating the chip between an upper mold and a lower mold; The upper mold and the lower mold are relatively moved to make the mold release film contact with the potting resin, forming an irregular surface texture of the plastic sealing layer on the surface of the potting resin, and manufacturing a chip plastic sealing material structure with a surface texture.

[0016] The above mold release film and its manufacturing method and chip plastic packaging material surface treatment process have at least the following beneficial effects: 1. By using polyester resin, powder will not fall off and contaminate the fixture and cavity during epoxy molding compound (EMC) packaging, which is easy to use and has a high process yield; 2. Existing release films usually use inorganic fillers such as titanium dioxide to form a micro-concave and convex surface texture, while in the mold release film of the present application, an irregular surface texture is formed by an embossing coating process. The surface texture of the mold release film used for transfer does not contain inorganic powder components, thereby completely changing the original powder loss problem. Therefore, there is no need to use a cleaning jig, and there is no pollution caused by powder loss; 3. In the mold release film of the present application, the surface texture of the mold release film is changed by embossing the matte film, so that the chip surface can achieve the purpose of abrasion resistance, good heat dissipation, and improved visibility and recognition of printing or laser printing; 4. In the mold release film of the present application, the unsaturated resin is a synthetic resin composed of unsaturated polyester and a crosslinking agent, and its main component is a polyester chain, which contains unsaturated double bonds and can react with the crosslinking agent to form a three-dimensional network structure. Due to this structure, the unsaturated polyester resin makes the release film have excellent mechanical properties, chemical resistance and heat resistance.

[0017] 5. In the mold release film of the present application, high TG polyester monomer is added to improve the temperature resistance and mechanical properties of the material. The unsaturated polyester resin forms a larger molecular chain during the cross-linking reaction. The test requirements of the mold release film are: temperature 180°C, pressure 30Mpa, time 2 hours. If the material in this application is not used, it will contaminate the EMC plastic packaging material and even cause adhesion. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A schematic flow chart of a method for manufacturing a mold release film in an embodiment of the present invention is shown.

[0019] Figure 2 A schematic diagram showing the formation of a matte release film in the process of a method for manufacturing a mold release film in an embodiment of the present invention is shown.

[0020] Figure 3 A schematic diagram showing the formation of a mold release film in the process of a method for manufacturing a mold release film in an embodiment of the present invention is shown.

[0021] Figure 4The schematic diagram shows the structure of using the mold release film in the embodiment of the present invention to perform surface treatment on the chip plastic packaging material.

[0022] Figure 5 It is through Figure 4 Schematic diagram of the structure of a chip plastic packaging material with a slightly concave-convex surface produced by mold molding. DETAILED DESCRIPTION

[0023] The present invention will be described in detail below with reference to specific embodiments and accompanying drawings.

[0024] The embodiment of the present invention provides a mold release film, which includes a substrate and a surface layer formed on at least one side of the substrate, wherein the substrate is polyethylene terephthalate or polyethylene naphthalate, and the surface layer is basically made of a mixture of unsaturated polyester resin, high TG polyester monomer, curing agent, and organic solvent, and at least one of the surface layers is embossed with a predetermined pattern through a matte release film for transfer to the surface of a chip plastic packaging material. Thus, the surface layer is formed with a predetermined pattern, i.e., a micro-concave-convex structure, having the roughness required for the surface of the chip plastic packaging material, and because it is formed by embossing, not a micro-concave-convex structure formed by an inorganic filler, the problem of powder loss is completely avoided.

[0025] Among them, the polyethylene terephthalate (PET) used as the substrate is preferably a 25-75um film produced by Nanya or Xiangyu, and the polyethylene naphthalate (PEN) is preferably a 25-75um film produced by Teijin or DuPont.

[0026] Preferably, the mass ratio of each component of the surface layer is as follows: 15-25 parts of unsaturated polyester resin, 5-15 parts of high TG polyester monomer, 50-70 parts of organic solvent, and 1-5 parts of curing agent. More preferably, the mass ratio of each component of the surface layer is as follows: 15-20 parts of unsaturated polyester resin, 5-10 parts of high TG polyester monomer, 55-70 parts of organic solvent, and 1-5 parts of curing agent. Among them, unsaturated polyester resin refers to a polymer compound containing unsaturated double bonds generated by a condensation reaction of a dibasic acid and a diol. This embodiment preferably uses bisphenol A type unsaturated polyester, for example, bisphenol A modified epoxy vinyl resin. High TG polyester has non-crystalline saturated polyester resin or high Tg non-crystalline copolymer polyester resin. This embodiment preferably uses high TG polyester of Japan Toyobo Vylon GK-888 and Japan Toyobo Vylon 200.

[0027] Preferably, a polyurethane coating is formed on one side of the substrate, and the mass ratios of the components in the polyurethane coating are as follows: 10-20 parts of polyurethane, 5-15 parts of high TG polyester, 5-15 parts of titanium dioxide, 1-10 parts of curing agent, and 40-80 parts of solvent. The surface layer is formed on the other surface of the substrate opposite to the polyurethane coating. Specifically, the substrate can be formed with a polyurethane coating on one side, or neither side has a polyurethane coating. The advantage of forming a polyurethane coating on one side of the substrate is that, since a matte film structure, that is, a matte release film, needs to be made, the process is convenient and the matte release film is fully utilized. Therefore, the matte release film has two uses. One is that it can be used as a substrate for a mold release film, and the other is that it can be made into a matte release film to imprint the surface of the mold release film to form a surface layer texture.

[0028] Furthermore, when making the matte release film, a layer of silicone oil is applied on the surface of the matte film structure coating, that is, a layer of silicone oil is applied on the surface of the polyurethane coating. The dry amount of silicone oil is 1-3g / ㎡, and the release force is 5-20g / 25mm, which is convenient for release and demolding.

[0029] Preferably, the polyurethane coating is made by stirring and mixing the components uniformly, and then precisely coating, drying, and rolling up to form a matte film structure; the roughness Ra of the matte film structure is controlled between 0.1-2, and the roughness Rz is controlled between 3-15. The depth and texture of the micro-concave-convex structure in the matte film are set according to the requirements of the drawing.

[0030] In a preferred embodiment, a matte film is formed on one surface of the substrate, and the surface layer of the substrate is formed by uniformly coating the unsaturated polyester mixture fluid on the bright side of the matte film of the substrate, that is, the side where the matte film is not formed. Of course, it is also possible that no matte film is formed on both sides, and the polyester mixture fluid is directly coated on one or both surfaces of the substrate. When coating the polyester mixture fluid, it is preferred to first dilute the polyester mixture fluid with an organic solvent such as ethyl acetate, and uniformly coat the diluted fluid on the bright side of the matte film, that is, one or both surfaces of the substrate where the matte film is not formed. Then, the texture on the matte release film is embossed onto the polyester mixture fluid by a laminating roller to form an irregular surface texture, thereby completing the production of a single-sided or double-sided matte mold release film, that is, at least one side is formed with a micro-concave-convex structure, which is formed by embossing.

[0031] Preferably, the unsaturated polyester resin and the high TG polyester resin in the surface layer are mixed in a mass ratio of 2-2.5:1-1.5, and the preferred ratio is 2:1. Specifically, the curing agent is preferably an isocyanate or epoxy resin crosslinking agent; the organic solvent is preferably toluene, ethyl acetate, or a solvent formed by mixing toluene or ethyl acetate in a predetermined ratio, and the predetermined mass ratio of the two is preferably 50-60:40-50‌.

[0032] Furthermore, the polyester mixture fluid is mainly made by mixing unsaturated polyester resin, high TG polyester monomer, curing agent, organic solvent and antistatic liquid. Preferably, the polyester mixture fluid is made in two steps, the first step is: after adding unsaturated polyester resin to organic solvent for dispersion treatment for a predetermined time, adding high TG polyester monomer, stirring and reacting for a predetermined time, to obtain polyester fluid; the second step is: adding organic solvent into polyester fluid for stirring, then adding curing agent and continuing stirring, to obtain polyester resin fluid, that is, polyester mixture fluid.

[0033] See also Figure 1-3 , illustrating that an embodiment of the present invention also provides a method for manufacturing the mold release film as described above and a process for changing its structure, and the method for manufacturing the mold release film includes the following steps.

[0034] Step S10, preparation of polyester fluid: after adding unsaturated polyester resin to organic solvent for dispersion treatment for a predetermined time, adding high TG polyester monomer, stirring and reacting for a predetermined time to obtain polyester fluid; then adding organic solvent into polyester fluid for stirring, and then adding curing agent and continuing stirring to obtain polyester resin fluid.

[0035] In step S10, the fluid is prepared in two steps, and the specific process is as follows: In the first step, after adding the unsaturated polyester resin to the organic solvent for dispersion treatment for 15min to 20min, the high TG polyester monomer is added, and the reaction is stirred at 75°C for 8h, and the stirring speed is 160r / min. The entire reaction is in a temperature-controlled reactor to obtain a high-temperature resistant polyester fluid. In the second step, the organic solvent is added to the obtained high-temperature resistant polyester fluid and stirred for 30min to 40min, and then the curing agent is added and stirred for 10-30min at a stirring speed of 350r / min. After stirring evenly, a polyester resin fluid, that is, a polyester mixture fluid, is obtained.

[0036] Step S20, matte film production: polyester fluid production: polyethylene terephthalate or polyethylene naphthalate is selected as the substrate, the substrate is divided into two parts, the first part is the mold release film substrate, and the second part is the matte release film substrate. A layer of polyurethane coating is coated on the surface of the matte release film substrate to make a matte release film; In step S20, Figure 2As shown in (a), a layer of polyurethane coating 102 is coated on the surface of the substrate 101. The polyurethane coating 102 adopts the above composition, that is, 10-20 parts of polyurethane, 5-15 parts of high TG polyester, 5-15 parts of titanium dioxide, 1-10 parts of curing agent, and 40-80 parts of solvent. Among them, titanium dioxide can produce a matte film effect, that is, the surface presents a micro-concave-convex structure. Specifically, two substrates are prepared, one is directly used as a mold release film substrate, and the other surface is coated with a layer of polyurethane coating 102 to form a matte release film. In another specific embodiment, the two substrates are made in the same process, which is simple and avoids mixing. Preferably, at least one side of the two substrates is coated with a layer of polyurethane coating 102. In another preferred embodiment, the substrate used as a matte release film is preferably coated with a layer of polyurethane coating 102 on both sides, that is, both sides are made into a matte micro-concave-convex structure, so that any side can be used as a subsequent transfer prototype, and thus can be used as a double transfer.

[0037] Furthermore, solvent-based silicone oil is applied on the matte surface of the matte film, with a dry weight of 0.2 g / ㎡, and the matte release film is rolled up after drying. Figure 2 As shown in (b), a silicone oil layer 201 is applied on the surface of the polyurethane coating. The dry weight of the silicone oil layer 201 is 1-3 g / ㎡, and the release force is 5-20 g / 25 mm, which is convenient for release and demoulding.

[0038] Step S30, embossing to form a surface texture to make a mold release film: applying a polyester resin fluid on at least one surface of the mold release film substrate, and embossing the texture on the matte release film onto the polyester resin fluid to form an irregular surface texture to make the mold release film.

[0039] In step S30, Figure 3 As shown in (c), a substrate 301 is provided first. Figure 3 As shown in (d), a polyester mixture resin fluid is coated on a substrate 301, preferably on a bright surface, i.e., a surface without a matte structure, to form a polyester coating 302. When coating the polyester resin fluid, the polyester mixture resin fluid is first diluted with ethyl acetate, and the diluted fluid is evenly coated on the bright surface of the substrate 301. Then, to facilitate transfer, embossing is performed in a timely manner after the fluid is coated. For example, the texture on the matte release film formed in the previous step, i.e., the micro-concave-convex structure formed on the polyurethane coating 102, is embossed onto the polyester mixture resin fluid by a laminating roller, so that an irregular surface texture is formed on the polyester coating 302, i.e., a micro-concave-convex surface 303 (e.g., a micro-concave-convex surface 303) corresponding to the micro-concave-convex structure formed on the polyurethane coating 102 is formed. Figure 3 As shown in (e)), a matte mold release film 300 is produced.

[0040] In another optional embodiment, both sides of the substrate 301 can be coated with a polyester mixture resin fluid, and both the upper and lower surfaces have a polyester coating 302. In this way, the polyester coating 302 can be applied to both sides in turn, and then the matte release film formed in the previous step can be pressed on the polyester coating 302 by a laminating roller, thereby completing the double-sided matte mold release film.

[0041] In addition, in the above embodiment, the surfaces of the two substrates are coated with a layer of polyurethane coating 102 to form a matte release film. At this time, one is taken as the transfer master mold, and the other is subjected to the operation in the above step S30, that is, the polyester mixture resin fluid is first coated, preferably on the bright surface, that is, on the surface without matte structure, to form a polyester coating 302; then an irregular surface texture is formed on the polyester coating 302, and a double-sided matte mold release film can also be made. In other words, a polyurethane coating is formed on one surface of the mold release film substrate and a matte film structure is formed, and the other surface is pressed by a laminating roller to imprint the texture on the matte release film onto the polyester resin fluid to form a double-sided matte mold release film. Due to the micro-concave-convex structure transferred, the matte film structure on any side of the above-mentioned mold release film is basically the same as the matte structure of the matte release film.

[0042] Specifically, the specific process of obtaining the polyester resin fluid is as follows: after adding the unsaturated polyester resin to the organic solvent for dispersion treatment for 15min to 20min, adding the high TG polyester monomer, stirring and reacting at 75°C for 8h to obtain a high temperature resistant polyester fluid; then adding the organic solvent into the polyester fluid and stirring for 30min to 40min, then adding the curing agent and continuing to stir for 15min to 20min to obtain the polyester resin fluid, that is, the polyester mixture resin fluid.

[0043] In addition, an embodiment of the present invention further provides a chip molding material surface treatment process, which includes the following steps: Step S40, making a mold release film using the mold release film making method as described above; Step S50, placing the encapsulating resin encapsulating the chip between the upper mold and the lower mold; Step S60, relatively moving the upper mold and the lower mold to make the mold release film contact with the potting resin, forming an irregular plastic layer surface texture on the surface of the potting resin, and manufacturing a chip plastic material structure with a surface texture.

[0044] Step S40 is the same as the process of the aforementioned method for making the mold release film, and will not be described again herein.

[0045] Step S50, see Figure 4, the potting resin 403 encapsulating the chip is placed between the upper mold 401 and the lower mold 402, for example, fixed by vacuum adsorption. A discharge cylinder 405 and a receiving cylinder 406 are respectively provided on both sides of the mold. The discharge cylinder 405 is wound with any of the mold release films 300 made as described above, and is conveyed by rollers 407 to reach the cavity of the lower mold 402. It is also preferred to use vacuum adsorption to hold the mold release film 300 (the figure only shows that the film inside the cavity has a micro-concave-convex structure). Then, step S60 is performed to relatively move the upper mold 401 and the lower mold 402 so that the upper mold 401 and the lower mold 402 are molded together, and the mold release film 300 is in contact with the surface of the potting resin 403, and an irregular plastic sealing layer surface texture 408 is formed on the surface of the potting resin 403. The specific molding result is as follows. Figure 5 As shown in the figure, a chip molding compound structure with surface texture is made. In this surface treatment process, the mold release film serves the purpose of sealing and easy peeling.

[0046] The following uses multiple examples to illustrate the method of making the mold release film, as well as the produced positive electrode materials and battery performance.

[0047] Example 1 Weigh 20 parts of unsaturated polyester resin, 10 parts of high TG polyester resin, 5 parts of curing agent, and 65 parts of organic solvent, put the unsaturated polyester resin, high TG polyester resin, and organic solvent into a temperature-controlled reactor, heat to 75°C, start the stirrer and stir for 40 minutes at a stirring speed of 160 r / min, then obtain mixture A, add the curing agent into the reactor, adjust the stirring speed to 350 r / min, and obtain polyester resin fluid after stirring evenly; Weigh 20 parts of polyurethane, 10 parts of high TG polyester, 8 parts of titanium dioxide, 2 parts of curing agent, and 60 parts of solvent. Add the organic solvent into the polyester resin and stir for 30 to 40 minutes. After mixing evenly, apply it on the surface of a 0.036 mm PET film, dry it, and then roll it up to make a matte film.

[0048] Apply solvent-based silicone oil on the matte surface of the matte film, with a dry amount of 0.2g / ㎡, and roll it up after drying to make a matte release film.

[0049] The polyester fluid is diluted with ethyl acetate, and the diluted polyester fluid is evenly coated on the bright surface of the matte film. The texture on the matte release film is embossed onto the polyester fluid by a laminating roller to form an irregular surface texture, thereby completing the double-sided matte mold release film.

[0050] Example 2 Weigh 15 parts of unsaturated polyester resin, 5 parts of high TG polyester resin, 1 part of curing agent, and 80 parts of organic solvent, put the unsaturated polyester resin, high TG polyester resin, and organic solvent into a temperature-controlled reactor, heat to 75°C, start the stirrer and stir for 40 minutes at a stirring speed of 160 r / min, then obtain mixture A, add the curing agent into the reactor, adjust the stirring speed to 350 r / min, and obtain polyester resin fluid after stirring evenly; Weigh 10 parts of polyurethane, 5 parts of high TG polyester, 5 parts of titanium dioxide, 1 part of curing agent, and 80 parts of solvent. Add the organic solvent into the polyester resin and stir for 30 to 40 minutes. After mixing evenly, apply it on the surface of a 0.036 mm PET film, dry it, and then roll it up to make a matte film.

[0051] Apply solvent-based silicone oil on the matte surface of the matte film, with a dry amount of 0.2g / ㎡, and roll it up after drying to make a matte release film.

[0052] The polyester fluid is diluted with ethyl acetate, and the diluted polyester fluid is evenly coated on the bright surface of the matte film. The texture on the matte release film is embossed onto the polyester fluid by a laminating roller to form an irregular surface texture, thereby completing the double-sided matte mold release film.

[0053] Example 3 Weigh 25 parts of unsaturated polyester resin, 15 parts of high TG polyester resin, 5 parts of curing agent, and 55 parts of organic solvent, put the unsaturated polyester resin, high TG polyester resin, and organic solvent into a temperature-controlled reactor, heat to 75°C, start the stirrer and stir for 40 minutes at a stirring speed of 160 r / min, then obtain mixture A, add the curing agent into the reactor, adjust the stirring speed to 350 r / min, and obtain polyester resin fluid after stirring evenly; Weigh 20 parts of polyurethane, 15 parts of high TG polyester, 15 parts of titanium dioxide, 10 parts of curing agent, and 40 parts of solvent. Add the organic solvent into the polyester resin and stir for 30 to 40 minutes. After mixing evenly, apply it on the surface of a 0.036 mm PET film, dry it, and then roll it up to make a matte film.

[0054] Apply solvent-based silicone oil on the matte surface of the matte film, with a dry amount of 0.3g / ㎡, and roll it up after drying to make a matte release film.

[0055] The polyester fluid is diluted with ethyl acetate, and the diluted polyester fluid is evenly coated on the bright surface of the matte film. The texture on the matte release film is embossed onto the polyester fluid by a laminating roller to form an irregular surface texture, thereby completing the double-sided matte mold release film.

[0056] Performance tests were conducted on the mold release films in Examples 1 to 3, and the test results are shown in Table 1.

[0057] Table 1 Mold release film performance test results

[0058] It should be noted that the present invention is not limited to the above-mentioned embodiments. Based on the creative spirit of the present invention, those skilled in the art may also make other changes. These changes made based on the creative spirit of the present invention should be included in the scope of protection required by the present invention.

Claims

1. A mold release film, characterized in that: It includes a substrate and a surface layer formed on at least one side of the substrate, wherein the substrate is polyethylene terephthalate or polyethylene naphthalate, and the surface layer is basically made of a mixture of unsaturated polyester resin, high TG polyester monomer, curing agent, and organic solvent. At least one of the surface layers is embossed with a predetermined pattern through a matte release film for transfer to the surface of the chip plastic packaging material.

2. The mold release film according to claim 1, characterized in that: The mass ratios of the components of the surface layer are as follows: 15 to 25 parts of unsaturated polyester resin, 5 to 15 parts of high TG polyester monomer, 50 to 70 parts of organic solvent, and 1 to 5 parts of curing agent.

3. The mold release film according to claim 1, characterized in that: A polyurethane coating is formed on one side of the substrate, and the weight ratios of the components in the polyurethane coating are as follows: 10-20 parts of polyurethane, 5-15 parts of high TG polyester, 5-15 parts of titanium dioxide, 1-10 parts of curing agent, and 40-80 parts of solvent; the surface layer is formed on the other surface of the substrate opposite to the polyurethane coating.

4. The mold release film according to claim 3, characterized in that: The polyurethane coating is prepared by mixing various components uniformly, and then precisely coating, drying, and rolling up to form a matte film structure; the roughness Ra of the matte film structure is controlled between 0.1-2, and the roughness Rz is controlled between 3-15.

5. The mold release film according to claim 1, characterized in that: A matte film is formed on one surface of the substrate, and the surface layer is formed by evenly coating an unsaturated polyester mixture fluid on the bright surface of the matte film of the substrate, and the texture on the matte film is pressed onto the fluid by a laminating roller to form an irregular surface texture, so as to produce a double-sided matte mold release film.

6. The mold release film according to claim 1, characterized in that: The unsaturated polyester resin and the high TG polyester resin in the surface layer are mixed in a mass ratio of 2-2.5:1-1.5; the curing agent is an isocyanate or epoxy resin crosslinking agent; the organic solvent is toluene, ethyl acetate or a solvent formed by mixing toluene or ethyl acetate in a predetermined ratio.

7. A method for producing a mold release film according to any one of claims 1 to 6, characterized in that: The following steps are involved: After adding unsaturated polyester resin to an organic solvent for a predetermined time, a high TG polyester monomer is added and stirred for a predetermined time to obtain a polyester fluid; then, an organic solvent is added to the polyester fluid for stirring, and then a curing agent is added and stirred to obtain a polyester resin fluid; Polyethylene terephthalate or polyethylene naphthalate is selected as the substrate, and the substrate is divided into two parts, the first part is a mold release film substrate, and the second part is a matte release film substrate, and a layer of polyurethane coating is coated on the surface of the matte release film substrate to make a matte release film; The polyester resin fluid is coated on at least one surface of the mold release film substrate, and the texture on the matte release film is embossed on the polyester resin fluid to form an irregular surface texture to produce the mold release film.

8. The method for producing a mold release film according to claim 1, wherein: A polyurethane coating is formed on one surface of the mold release film substrate to form a matte film structure, and the other surface is embossed with the texture on the matte release film onto the polyester resin fluid by a bonding roller to form a double-sided matte mold release film; the matte film structure on either side of the mold release film is basically the same as the matte structure of the matte release film.

9. The method for producing a mold release film according to claim 1, wherein: The specific process of obtaining the polyester resin fluid is as follows: after adding the unsaturated polyester resin to the organic solvent for dispersion treatment for 15 minutes to 20 minutes, adding the high TG polyester monomer, stirring and reacting at 75°C for 8 hours to obtain a high temperature resistant polyester fluid; then adding the organic solvent into the polyester fluid and stirring for 30 minutes to 40 minutes, then adding the curing agent and continuing to stir for 15 minutes to 20 minutes to obtain the polyester resin fluid.

10. A chip plastic packaging material surface treatment process, characterized in that: The following steps are involved: A mold release film is made by using the method for making a mold release film according to any one of claims 7 to 9; placing a potting resin encapsulating the chip between an upper mold and a lower mold; The upper mold and the lower mold are relatively moved to make the mold release film contact with the potting resin, forming an irregular surface texture of the plastic sealing layer on the surface of the potting resin, and manufacturing a chip plastic sealing material structure with a surface texture.

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