WO2019091305A1

WO2019091305A1 - Anti-scratch transparent thin film, scratch-resistant surface article and composite sheet

Info

Publication number: WO2019091305A1
Application number: PCT/CN2018/112835
Authority: WO
Inventors: 廖洪传
Original assignee: 廖洪传
Priority date: 2017-11-08
Filing date: 2018-10-31
Publication date: 2019-05-16

Abstract

Disclosed are an anti-scratch transparent thin film, a scratch-resistant surface article and a composite sheet. The anti-scratch transparent thin film comprises a PMMA layer located on an upper layer and a PET layer provided on the lower surface of the PMMA layer. The PET layer is selected from PETG (non-crystalline copolymerized PET), APET (amorphous PET) or CPET (crystalline PET) layers. The thickness of the PMMA layer accounts for 5%-40% of the total thickness, and the thickness of the PET layer accounts for 20%-95% of the total thickness. A PMMA layer, a PC layer, or a PC layer and a PMMA layer can further be provided on the lower surface of the PET layer. The use of a PMMA layer as an outer surface layer of surface articles or packaging materials provides good scratch resistance, better weathering resistance, and better temperature resistance, and at the same time, using a PET layer to directly composite with a PMMA layer also overcomes the defects of the fragility and high cost of the PMMA layer itself.

Description

Anti-scratch transparent film, scratch-resistant surface product and composite sheet

Technical field

The invention relates to a scratch-resistant transparent film and a scratch-resistant surface product, which may be a film, a casing, a protective cover, a window panel, a touch screen panel, other panels, windows, lenses, signs, etc., the transparent film Can be used for packaging materials and signs, panels, etc.

Background technique

At present, the surface products of many products are film or injection molded parts of PMMA, PC, PET, PP and other resins. However, the performance of a single material often cannot meet the requirements of impact resistance, scratch resistance, and low cost of some surface products. For example, the impact resistance of PC is very good, but the hardness is not enough, it is easy to scratch, and the scratch resistance after hardening treatment is still not good enough; while PMMA is high in hardness, it is susceptible to impact and brittle.

Among them, plastic transparent film has a wide range of applications in the packaging field, mainly PET, PC, PMMA, PVC, PP, PE and PS materials, among which PVC does not meet the environmental protection trend, is banned in many countries and enterprises; PP, PE The transparency is poor; PS is easy to be brittle, the processing is general, and solvent bonding is not possible; PMMA transmittance and hardness are higher than other materials, Rockwell hardness (R scale) is 118, not easy to scratch, Solvent bonding, heat sealing, ultrasonic welding, etc., weather resistance is the best of all thermoplastics, temperature resistance is higher than PETG, heat distortion temperature is about 84 ° C, but the cost is higher, close to PETG, PC, processing It is also easy to be brittle and easy to stress crack; PC has high transparency and high strength, but it is costly and cannot be glued with solvent. It is limited in the processing field (such as manual box) where fast bonding is required. PET is divided into ordinary amorphous PET (commonly known as APET) and PETG, which has good environmental protection. Among them, APET film cost is much lower than PC and PMMA, but it is easy to crystallize and white, and can not be processed by solvent bonding or heat sealing. ; PETG due to the polymerization process Adding 1,4-cyclohexanedimethanol to form a non-crystalline copolymer, so it can be solvent-bonded, heat-sealed, ultrasonically welded, etc., but the cost is comparable to PC, and the hardness is too low, Rockwell hardness (R scale) ) Only about 105, the temperature resistance is also relatively poor, the heat distortion temperature is only about 70 °C. In summary, the defects of the existing plastic transparent film are mainly high cost, easy to scratch, brittle, and stress cracking. Therefore, no film material can achieve low cost, scratch resistance, brittleness, and stress resistance at the same time. Cracking.

In addition, for surface products, the performance of a single material often does not meet the various requirements of some surface products. With the development of new technology in-mold decoration technology (IMD), a new technology trend is to use the composite sheet combined with the IMD process to make the outer shell of the product, apply printing on the surface of the film, high-pressure molding, die-cutting, and Hard treatment, combined with other materials by IMD process. The representative of this kind of composite sheet is PMMA/PC two-layer composite material. The surface layer of the material is PMMA layer, wear-resistant, which is the outer surface of the outer shell of the product, and the other layer is PC layer. The toughness is good, and it is the inner surface of the outer shell of the product. . At present, PMMA/PC composite materials are being rapidly promoted. However, the disadvantage of this material is that the PC is susceptible to stress cracking, resulting in poor overall product performance, and the overall cost of the product is higher in general-purpose thermoplastics.

Summary of the invention

The present invention provides a scratch-resistant transparent film, a scratch-resistant surface article, and a composite sheet, and a process for the preparation thereof.

The technical solution of the present invention is as follows:

An anti-scratch transparent film for use in a packaging material comprising a PMMA layer on an upper layer of the film and a PETG or APET layer disposed on a lower surface of the PMMA layer, the thickness of the PMMA layer being a total thickness 5 to 40%, the thickness of the PETG or APET layer is 20 to 95% of the total thickness, and more preferably, the thickness of the PETG or APET layer is 60 to 95% of the total thickness. The total thickness refers to the total thickness of all structural layers of the PMMA layer, the PETG or APET layer and possibly additional PC layers, PMMA layers, etc., but does not include the thickness of the additional layer obtained by surface treatment.

In a preferred embodiment of the invention, the PMMA layer has a thickness that is less than the thickness of the PETG or APET layer.

In one embodiment of the present invention, a PMMA layer is further disposed on a lower surface of the PETG or APET layer, the PMMA layer having a thickness of 5 to 40% of the total thickness, and the PETG or APET layer is preferably used at this time. The thickness is 20 to 90% of the total thickness.

Preferably, the total thickness of the film is from 0.1 to 6 mm, more preferably from 0.1 to 3 mm, still more preferably from 0.15 to 0.95 mm.

When the total thickness of the transparent film is 0.5 mm or less, the ratio of the thickness of the single layer of the PMMA layer to the total thickness is preferably 10 to 15%, and the ratio of the thickness of the PETG or APET layer to the total thickness is preferably 70 to ～. 90%; when the total thickness of the transparent film is more than 0.5 mm, the ratio of the thickness of the single layer of the PMMA layer to the total thickness is preferably 5 to 10%, and the ratio of the thickness of the PETG or APET layer to the total thickness is preferably 80 to 95%. Such a thickness ratio setting is better while achieving the effects of low cost, scratch resistance, brittle fracture, and stress cracking.

Preferably, the hardness of the film is higher than the hardness of the PETG or APET layer, and the Rockwell hardness R scale of the film is not less than 110.

Preferably, the film has a light transmittance of more than 86%, and more preferably the film has a light transmittance of more than 90%.

Preferably, the PMMA layer may contain no PET or contain a small amount of PET, and the content of PET ranges from 0 to 50%, preferably from 0 to 40%, more preferably from 0 to 30%; the PETG or APET layer may not The content of PMMA or PMMA is preferably 0 to 50%, preferably 0 to 40%, more preferably 0 to 30%.

In a preferred embodiment of the invention, the PMMA layer is directly joined to the PETG or APET layer by a co-extrusion process.

The invention also discloses a preparation method of the above-mentioned anti-scratch transparent film, which comprises extruding PMMA from one extruder, melting the material to the distributor, and making PETG or APET from another extruder. Extrusion plasticization, the molten material also flows to the distributor, wherein the PMMA is divided into one or two melt streams in the distributor, and the distributor is stacked on one or both sides of the PETG or APET layer to form two layers. Or a three-layer structure, which is cooled and formed into a solid film after flowing out of the die.

The invention also discloses another preparation method of the above-mentioned anti-scratch transparent film, comprising: extruding PMMA from a first extruder, flowing molten material to a distributor, and pressing PETG or APET from the second extruder Extrusion and plasticization, the molten material also flows to the distributor, and the PMMA is extruded and plasticized from the third extruder. The molten material flows to the distributor and is extruded and plasticized from the first and third extruders. The PMMA molten material is superposed on both sides of the distributor and the PETG or APET layer to form a three-layer structure, which is cooled and formed into a solid film after flowing out of the die.

In the above preparation method, each molten material may also be laminated to form a multilayer structure at the die.

The anti-scratch transparent film of the invention has the combination of PMMA and PETG or APET layer structure as the main structural layer, and at the same time achieves the effects of low cost, scratch resistance, brittle fracture and stress cracking. In addition, various functional layers such as a hardened layer, an anti-glare layer, an anti-fingerprint layer and the like can be attached thereto.

The present invention also provides a scratch resistant surface article made from a scratch resistant composite sheet comprising a layer of PET, the upper layer of the PET layer A PMMA layer is provided, and the PMMA layer of the upper layer is used as an outer surface of the scratch-resistant composite sheet, the PMMA layer has a thickness of 5 to 40% of the total thickness, and the thickness of the PET layer accounts for 20 to 95% of the thickness. Further preferably, the thickness of the PET layer is 60 to 95% of the total thickness.

The anti-scratch composite sheet of the present invention has a combination of a PMMA and a PET layer structure as a main structural layer, and at the same time achieves the effects of low cost, scratch resistance, brittle fracture and stress cracking. In addition, various functional layers such as a hardened layer, an anti-glare layer, an anti-fingerprint layer and the like may be attached thereto to thereby obtain a scratch-resistant surface product.

Preferably, the total thickness of the scratch-resistant composite sheet is from 0.1 to 6 mm, more preferably from 0.1 to 0.95 mm, still more preferably from 0.1 to 0.49 mm.

The PET layer of the scratch-resistant composite sheet may have no lower layer or a lower layer, and in the case of providing a lower layer, the lower layer is:

PMMA layer, at this time, the scratch-resistant composite sheet has a three-layer structure, referred to as PMMA/PET/PMMA composite sheet; or

PC layer, at this time, the scratch-resistant composite sheet has a three-layer structure, referred to as PMMA/PET/PC composite sheet; or

The PC layer is further provided with a PMMA layer under the PC layer. At this time, the scratch-resistant composite sheet has a four-layer structure, which is referred to as a PMMA/PET/PC/PMMA composite sheet.

The thickness of the above-mentioned possible additional lower layer is not associated with the PET layer and the upper PMMA layer, and may be any thickness if it is a PC layer, and is 0.01 mm to 2 mm if it is a PMMA layer.

When the total thickness of the scratch-resistant composite sheet is 0.5 mm or less, the thickness ratio of the lower PMMA layer or the PMMA layer to the PC layer is 10 to 15%; the total thickness of the composite sheet is greater than 0.5 In the case of mm, the thickness ratio of the lower PMMA layer or the PMMA layer to the PC layer is 5% to 10%.

Preferably, the PMMA layer and the PET layer of the scratch-resistant composite sheet are directly compounded together by co-extrusion.

The preparation method of the scratch-resistant composite sheet comprises: extruding PMMA from one extruder, melting the molten material to the dispenser, and extruding the PET from another extruder, and the molten material also flows toward a dispenser, wherein the PMMA is divided into one or two layers of melt stream in the distributor, and is stacked on one side or both sides of the distributor layer to form a two-layer or three-layer structure, and is cooled and formed after flowing out of the die. It is a solid sheet.

The anti-scratch composite sheet can also be prepared by: extruding PMMA from the first extruder, flowing the molten material to the dispenser, and extruding the PET from the second extruder. The molten material also flows to the distributor, and the PMMA is extruded and plasticized from the third extruder, and the molten material flows to the distributor, and the plasticized PMMA molten material is extruded from the first and third extruders in the distributor. It is laminated with both sides of the PET layer to form a three-layer structure, which is cooled and formed into a solid sheet after flowing out of the die.

The invention also discloses another preparation method of the above-mentioned co-extruded composite sheet. In the above two preparation methods, an extruder is further added to extrude the PC, and the molten PC flows to the distributor in the basic structure PMMA/PET layer. The PET layer is superposed on the outside to form a PMMA/PET/PC three-layer structure or a PMMA/PET/PC/PMMA four-layer structure, which is cooled and formed into a solid sheet after flowing out of the die. In addition to the above methods, the PC layer can also be composited by IMD after the PET layer and the PMMA layer are co-extruded.

Preferably, the PET layer of the composite sheet used is amorphous PET (APET), or crystalline PET (CPET) with a nucleating agent, or modified PET (PETG) without crystallization, or either or both The three are mixed in any proportion. Among them, the temperature resistance of the crystalline PET (CPET) to which the nucleating agent is added is improved, thereby improving the temperature resistance of the composite sheet; the cost of the APET is greatly reduced compared with the PC used in the prior art; The APET layer or the CPET layer does not have the stress cracking problem of the PC layer (stress cracking refers to cracking due to stress concentration when there is slight scratch or gap and then stress), and the composite sheet also has good toughness and good Scratch resistance.

Preferably, the PET layer of the composite sheet has a PET content of 10% to 100%, preferably 50% to 100%, more preferably 60% to 100%, still more preferably 70% to 100%, further It is preferably 90% to 100%. The other component that the PET layer may contain may be PMMA. For example, based on the scrap recycling process, the scrap containing all the components is added as a raw material to the PET layer of the subsequent process, and PMMA is introduced into the PET layer, resulting in PET in the PET layer. The content is not always 100%. Alternatively, other polymers that do not significantly affect their toughness are added to the PET layer for any other reason.

Preferably, one or more of the layers constituting the composite sheet may be added with a lubricant which is added to the matrix of the layers. The addition of a lubricant facilitates extrusion processing and increases the smoothness of the surface layer, which in turn helps to prevent scratching.

In addition, one or more functional additives may be added to one or more layers constituting the composite sheet, for example, an antioxidant, an ultraviolet absorber, and a coupling agent for increasing the binding force between the PC layer and the PET layer. And compatibilizers (such as some terpolymers), nucleating agents, etc., as well as glass fiber, calcium carbonate, barium sulfate and other fillers, as well as toner, color masterbatch and so on.

Preferably, the composite sheet has a Rockwell hardness R scale of not less than 110.

Preferably, the PMMA layer of the composite sheet may contain no or a small amount of PET, and the content of PET ranges from 0 to 50%, preferably from 0 to 40%, more preferably from 0 to 30%; The PMMA may be contained or contained in a small amount of 0 to 50%, preferably 0 to 40%, more preferably 0 to 30%.

The method for preparing the scratch-resistant surface product is: subjecting the scratch-resistant composite sheet to surface hardening, cold stamping, hot press forming (including various molding processes such as heat bending and suction). Plastic, etc.), IMD (including IML, IMF, IMR), anti-fingerprint treatment, anti-glare treatment, hydrophobic oleophobic treatment, vacuum evaporation, in-mold labeling, printing, electroplating, one or more processes, Made into a variety of scratch-resistant surface products, including but not limited to the following types of surface products: dashboard, automotive interior parts, casing, protective cover, panel, touch screen panel, window, signage, buttons, lenses, mobile phone back cover, Products such as MP3/MP4/DVD/digital photo frame/GPS navigator/meter, etc.

Specifically, the method of preparing the scratch-resistant surface article from the scratch-resistant composite sheet may be, for example, one of the following:

(1) The above two-layer composite sheet PMMA/PET or three-layer composite sheet PMMA/PET/PC, PMMA/PET/PMMA or four-layer composite sheet PMMA/PET/PC/PMMA is injection molded by IML Various types of protective stickers, either hot-pressed or high-pressure molded, or directly molded with an additional PC or PET layer using IMD technology, thus eliminating the need for any adhesive, resulting in instrument panels and automotive interior parts Surface products.

(2) Anti-glare treatment can be performed on the above-mentioned scratch-resistant composite sheet to form surface products such as window panels, lenses, and signs. The anti-glare treatment method may be an anti-glare layer method (that is, adding anti-glare particles to the coating liquid to form a micro-concave appearance on the surface after the coating is dried and solidified, so that the incident light is diffusely reflected to achieve an anti-glare effect); Vacuum evaporation, vapor deposition, sputtering, embossing, sand blasting, chemical etching, etc. can also be used to achieve micro-concave appearance to achieve anti-glare effect.

(3) Anti-fingerprint treatment can be carried out on the above-mentioned anti-scratch composite sheet (by applying a hydrophobic oleophobic layer on the surface of the product, the coating is usually a fluorine-containing material such as perfluoropolyether, as mentioned below) The anti-fingerprint treatment is as described here), and various anti-fingerprint panels, protective films, signs and other surface products are produced.

(4) The surface of the above-mentioned scratch-resistant composite sheet is subjected to surface hardening treatment (for example, a hard layer is applied, and the hard layer is, for example, one containing silicone, titanium oxide, dicyandiamide, a cobalt compound, and an organic polycarboxylic acid). Or a variety of coatings, the hardened layer mentioned below is the same as described herein), UV hardening treatment, combined with the printing process, to produce various types of electronic, touch screen panels or display perspective windows, signs, buttons and other surface products . The PMMA surface layer of the composite board can be hardened. In addition, the surface layer can also be treated with special functions such as AF (anti-fingerprint), AG (anti-glare), and anti-fog.

(5) The above-mentioned scratch-resistant composite sheet is subjected to printing, UV texture production, electroplating, undercoating, slitting, cold stamping or hot press forming, surface hardening treatment, CNC engraving, IMD (in-mold decoration process, including IML, IMF, IMR, the same below) or one or more processes in the process of lamination, anti-glare, anti-fingerprint, etc., to make a product shell or panel that can be used for scratch protection, such as a mobile phone back cover, a protective cover and Panels such as MP3/MP4/DVD/Digital Photo Frame/GPS Navigator/Instrument.

(6) The above-mentioned scratch-resistant composite sheet is coated with a reflective layer by vacuum evaporation, in-mold labeling, silk screen printing, plating, or the like to form a lens. The surface of the lens can be surface treated with hardening, anti-glare and anti-fingerprint.

The present invention also provides an anti-scratch composite sheet which is the scratch-resistant composite sheet or composite sheet of any of the above.

Compared with the prior art, the beneficial effects of the present invention are as follows:

First, the commonly used packaging material film and scratch-resistant surface products are mainly made of PMMA and PC, and the cost of these two raw materials is relatively high; and in most cases, the APET layer can be used as the The film and the main material of the composite sheet are used, thereby effectively reducing the cost of the product;

2. A scratch-resistant transparent film and scratch-resistant surface article for packaging materials according to the present invention, which can be provided by providing a PMMA layer on the upper surface of the PETG or APET layer and an outer layer of the PMMA layer as a packaging material. Good scratch resistance, avoiding being scratched by slight friction, maintaining the effect of beauty and light transmission; and long-term outdoor exposure to sunlight and wind and rain, the appearance change is small, and has better weather resistance;

3. A scratch-resistant transparent film and scratch-resistant surface product for packaging materials of the present invention, in which two materials of PET and PMMA are skillfully selected and directly combined (for example, by a co-extrusion process, when extruded) The compatibilizer can be added to increase the bonding strength), and the adhesive is not added, so that the defects of the PMMA layer being brittle and stress cracking are well overcome by the PET layer, and the PET layer is not easily brittle, and can be pressed, punched, Folding and the like without cracking, and at the same time, the scratch-resistant performance of the PET layer is significantly improved by the complement of the PMMA layer;

4. In a scratch-resistant transparent film and scratch-resistant surface product for packaging materials of the present invention, the heat distortion temperature of PMMA is 84 ° C, which is 14 ° C higher than the PETG heat distortion temperature (about 70 ° C), so Anti-scratch transparent film and scratch-resistant surface products can better withstand high temperature environment during storage, transportation and use without softening deformation and stickiness;

5. The scratch-resistant transparent film and scratch-resistant surface product for packaging materials of the present invention also fully utilizes the high light transmittance of PMMA, thereby improving the overall light transmittance of the product;

6. For products having higher temperature resistance and impact resistance requirements, the present invention can use a composite sheet having a PC layer, such as a PMMA/PET/PC composite sheet and a PMMA/PET/PC/PMMA composite sheet, The scope of application of the present invention is more extensive.

Of course, implementing any of the products of the present invention does not necessarily require all of the advantages described above to be achieved at the same time.

DRAWINGS

1 is a schematic structural view of a scratch-resistant transparent film for a packaging material according to an embodiment of the present invention;

2 is another schematic structural view of a scratch-resistant transparent film for a packaging material according to an embodiment of the present invention;

3 is a schematic structural view of a scratch-resistant composite sheet used in a scratch-resistant surface product according to an embodiment of the present invention;

In the figure, a 1-PMMA layer; a 2-PET layer; a 3-PC layer; a 4-PMMA layer.

Detailed ways

For the outer packaging film products, PET film is commonly used on the market, and its surface layer hardness is not high, it is easy to be scratched due to slight friction, affecting the effect of beauty and light transmission, and the heat distortion temperature is low, and the weather resistance is poor. Defects.

Generally, although PMMA is superior in hardness, light transmittance, and weather resistance, it has defects in processing and brittle fracture, and it is impossible to form a sheet of <0.5 mm due to brittle fracture, and the cost is also limited. Its use on packaging materials.

In addition, the prior art mainly uses PMMA as a base material optical film of a touch screen, and then applies a hardening agent to form an anti-scratch optical film. Therefore, the person in the field of outer packaging materials does not easily think of using the hardness of PMMA itself to help improve the hardness of other materials, especially because it is not applied to the packaging field due to cost factors.

Therefore, it is extremely important to develop an outer packaging material film which has both PET film properties and PMMA properties, and which is relatively low in cost.

Transparent PETG has a narrow selection range of grades, Rockwell hardness is basically 105-108 (R scale), transparent PMMA and PC have various hardness materials, some PMMA hardness is lower than PETG, and some PC hardness is higher than PMMA, such as Eastman Chemical's PETG GN120 has a Rockwell hardness (R scale) of 107, Mitsubishi's PMMA ShinkoLite-P UT-300 has a Rockwell hardness (R scale) of 100, and Shengao's PC 300-6 Rockwell hardness ( The R scale is 118.

In the present invention, PMMA having a hardness higher than that of PETG is used as a scratch-resistant surface layer, and PMMA is not required as a base material optical film.

The scratch-resistant transparent film of the present invention comprises a layer of PMMA at least on the upper surface of the PETG or APET layer, that is, an upper surface layer or a top and bottom surface layer with a PMMA layer as a packaging material, and a PETG or APET layer as a lower surface of the packaging material. The layer or sandwich layer not only utilizes the superior properties of PMMA in terms of hardness, light transmittance and weather resistance, but also the solvent-bonding in processing, and utilizes the flexibility of PETG or APET and the low cost of APET, that is, the use of one side. The advantage of a certain performance to solve the disadvantage of the other performance at the performance, and taking into account the cost factor, the film of the invention has scratch resistance, weather resistance, high transparency and processing in the pressing, punching, folding, etc. The process does not break, and the cost is relatively low. Usually, in order to reduce the cost, the APET layer is often used, and a small amount of PETG may be mixed therein, or no PETG may be added.

The scratch-resistant surface product of the invention has the PMMA layer as the outer surface layer of the surface product, provides good scratch resistance, avoids being scratched by slight friction, and provides better weather resistance even if it is exposed to sunshine for a long time. The appearance change in wind and rain is also small; better temperature resistance, no softening deformation and stickiness during storage, transportation and use; while APET layer or PETG layer provides sufficient strength mechanical properties for surface products, and The cost of the product casing is greatly reduced.

The invention is further illustrated below in conjunction with specific embodiments. It is to be understood that the examples are merely illustrative of the invention and are not intended to limit the scope of the invention. Improvements and modifications made by those skilled in the art in light of the present invention in the practical application are still within the scope of the present invention.

In order to better illustrate the invention, the invention will be described in detail below with reference to the accompanying drawings.

As shown in FIG. 1, a scratch-resistant transparent film or composite sheet for a packaging material of the present invention comprises a PMMA layer 1 on the upper layer of the film and a PETG disposed on the lower surface of the PMMA layer 1. Or APET layer 2 (ie, PET layer), the thickness of the PMMA layer 1 is 5-40% of the total thickness, and the thickness of the PETG or APET layer 2 is 20-95% of the total thickness, preferably, The thickness of the PETG or APET layer is 60 to 95% of the total thickness.

In another embodiment of the present invention, as shown in Fig. 2, a PMMA layer 3 is further provided on the lower surface of the PETG or APET layer 2, and the PMMA layer 3 has a thickness of 5 to 40% of the total thickness. In this case, it is preferred that the thickness of the PETG or APET layer is 20 to 90% of the total thickness.

Wherein, when PMMA is used as the upper surface layer or the upper and lower surface layers of the film packaging material, the thickness thereof is preferably 7 to 20%, and the thickness of the PETG or APET layer 2 is 30 to 90% of the total thickness.

In addition, various additives which do not significantly affect the transmittance of the film, such as antioxidants, ultraviolet absorbers, lubricants, and couplings for increasing the binding force of the PMMA layer to the PET layer, may be added to the layers of the film. Agents, etc.

The invention also discloses a preparation method of the above-mentioned anti-scratch transparent film for packaging materials, comprising PMMA extrusion plasticizing from one extruder, molten material flowing to the distributor, PETG or APET being squeezed from another extruder Extrusion plasticizing, the molten material also flows to the distributor, wherein PMMA is divided into one or two layers of melt stream in the distributor, and the distributor is stacked on one side or both sides of the PETG or APET layer to form A film of two or three layers.

Namely: PMMA is divided into two layers of melt stream in the distributor, and is stacked on both sides of the distributor and the PET layer to form a three-layer structure film; or, PMMA does not need to be divided into two layers at the distributor, and is directly laminated with PET. Forming a film of a two-layer structure. The laminated two or three layers of molten material continue to flow to the die, and are discharged from the die into a three-roll rapid cooling molding, and the film is obtained by trimming and winding.

In addition, the transparent film may also be produced by an in-mold compound co-extrusion process, that is, two or three layers of molten material are not stacked on the dispenser, but are stacked after entering the die; and those skilled in the art also It is known that when producing the three-layer co-extruded transparent film, PMMA can also be extruded and plasticized by two extruders to form two molten materials and stacked with another extruder to extrude the plasticized output of the PET melt. Hehe.

The present invention also provides a scratch resistant surface article made from a scratch resistant composite sheet comprising a layer of PET, the upper layer of the PET layer a PMMA layer is provided, and the PMMA layer disposed on the upper layer is used as an outer surface of the scratch-resistant composite sheet, and the thickness of the PMMA layer is 5-40% of the total thickness, and the thickness of the PET layer is It accounts for 20 to 95% of the total thickness.

The PET layer of the scratch-resistant composite sheet is not provided with a lower layer or a lower layer, and in the case of providing a lower layer, the lower layer is:

a PMMA layer, wherein the scratch-resistant surface product is a three-layer structure, referred to as a PMMA/PET/PMMA composite sheet; or

PC layer, at this time, the scratch-resistant surface product is a three-layer structure, referred to as PMMA/PET/PC composite sheet; or

The PC layer is further provided with a PMMA layer under the PC layer. At this time, the scratch-resistant surface product has a four-layer structure, which is referred to as a PMMA/PET/PC/PMMA composite sheet.

Referring to FIG. 3, in some embodiments of the present invention, the structure of the composite sheet includes: a PMMA layer 1 serving as an outer surface, a PET layer 2 disposed under the PMMA layer 1, and a PET layer 2 disposed under the PET layer 2. The PC layer 3 and the PMMA layer 4 disposed under the PC layer 3.

In a preferred embodiment of the invention, the composite sheet used in the scratch resistant surface article is a coextruded composite sheet. In addition to the coextrusion process, the lower PMMA layer, PC layer or PC+PMMA layer can also be bonded to the PET layer by the IMD process.

The PET layer of the composite sheet used in the present invention is amorphous PET (APET), or a crystalline PET (CPET) with a nucleating agent, or a non-crystalline copolymerized PET (PETG), or any two or three of them. Mix in any ratio.

The composite sheet has a total thickness of from 0.1 to 6 mm, preferably from 0.1 to 0.95 mm, more preferably from 0.1 to 0.49 mm. When the total thickness of the composite sheet is 0.5 mm or less, the thickness ratio of the lower PMMA layer or the PMMA layer to the PC layer is 10 to 15%; when the total thickness of the composite sheet is greater than 0.5 mm, The thickness ratio of the lower PMMA layer or the PMMA layer to the PC layer is 5% to 10%.

The PET layer of the composite sheet has a PET content of 10% to 100%, preferably 50% to 100%, more preferably 60% to 100%, still more preferably 70% to 100%, still more preferably 90%. %~100%.

The PMMA layer of the composite sheet does not contain or contain a small amount of PET, and the content of PET ranges from 0 to 50%, preferably from 0 to 40%, more preferably from 0 to 30%; the PET layer does not contain or The content of PMMA is preferably from 0 to 50%, preferably from 0 to 40%, more preferably from 0 to 30%.

The preparation method of the composite sheet comprises extrusion molding plasticized PMMA from one extruder, flowing the molten material to the distributor, and extruding the PET from another extruder, and the molten material also flows to the dispenser. Wherein, the PMMA is divided into one or two layers of molten streams in the distributor, and is stacked on one side or both sides of the distributor and the PET layer to form a two-layer or three-layer structure, which is cooled and formed into a solid piece after flowing out of the die. material.

The composite sheet can also be prepared by: extruding PMMA from the first extruder, flowing the molten material to the distributor, and extruding the PET from the second extruder, and melting the material. Flow to the distributor, and PMMA is extruded and plasticized from the third extruder, the molten material flows to the distributor, and the plasticized PMMA molten material is extruded from the first and third extruders in the distributor and the PET layer. The two sides are stacked together to form a three-layer structure, which is cooled and formed into a solid sheet after flowing out of the die.

The invention also discloses another preparation method of the above-mentioned co-extruded composite sheet. In the above two preparation methods, an extruder is further added to extrude the PC, and the molten PC flows to the distributor in the basic structure PMMA/PET layer. The outer side of the PET layer is laminated to form a three-layer structure of PMMA/PET/PC or a four-layer structure of PMMA/PET/PC/PMMA, which is cooled and formed into a solid film after flowing out of the die.

The scratch-resistant surface product is prepared by: surface-hardening, cold stamping, hot press forming, IMD, anti-glare treatment, hydrophobic oleophobic treatment, vacuum evaporation, in-mold One or more processes in labeling, printing, and electroplating to produce a variety of scratch-resistant surface products.

In some embodiments, one or more of the layers comprising the composite sheet may be added with a lubricant that is added to the matrix of each layer.

In some embodiments, one or more of the functional additives may also be added to one or more of the layers of the composite sheet. For example, antioxidants, UV absorbers, coupling agents and compatibilizers (such as some terpolymers), nucleating agents, etc., which increase the binding force between the PC layer and the PET layer, as well as glass fibers, calcium carbonate, barium sulfate, etc. Filler, as well as toner, color masterbatch, etc.

In a preferred embodiment, the composite sheet has a Rockwell R scale of not less than 110.

The present invention also provides an anti-scratch composite sheet which is the above-mentioned scratch-resistant composite sheet or composite sheet.

Example 1

A scratch-resistant transparent film for a packaging material according to the first embodiment, comprising a PMMA layer 1 disposed on the upper layer of the film, an APET layer 2 disposed on a lower surface of the PMMA layer 1, and the APET in the The lower surface of the layer 2 is further provided with a PMMA layer 3, the PMMA layer 1 having a thickness of 10% of the total thickness, and the APET layer 2 having a thickness of 80% of the total thickness, the PMMA layer 3 The thickness is 10% of the total thickness, and the total thickness of the film is 0.3 mm. The preparation method comprises the following steps: drying the PMMA pellets and the APET pellets separately, and conveying them to the co-extrusion sheet unit for extrusion molding; the performance test results are as shown in Table 1, and the PETG/APET/PETG film of the same thickness is used. The material was used as a control and its performance is shown in Table 2.

Table I

Table II

The cost of PMMA raw materials is basically the same as that of PETG raw materials. The above comparison shows that compared with the PETG/APET/PETG three-layer sheet currently on the market, the present invention significantly improves the hardness of the film at a constant cost, thereby significantly improving the scratch resistance of the film. In addition, the light transmittance has also been improved to some extent.

Example 2

A scratch-resistant transparent film for a packaging material according to Embodiment 2, comprising a PMMA layer 1 on an upper layer of the film and an APET layer 2 disposed on a lower surface of the PMMA layer 1, the PMMA layer The thickness of 1 is 20% of the total thickness, the thickness of the APET layer 2 is 80% of the total thickness, and the total thickness of the film is 0.25 mm. The preparation method comprises the following steps: drying the PMMA pellets and the PET pellets, and then conveying them to the co-extrusion sheet unit for extrusion molding; the performance test is as shown in Table 3, and the PETG/APET film material of the same thickness is used as a control. Its performance is shown in Table 4.

Table 3

Table 4

The above comparison shows that compared with the PETG/APET two-layer sheet currently on the market, the present invention significantly improves the hardness of the film at a constant cost, thereby significantly improving the scratch resistance of the film. In addition, the light transmittance has also been improved to some extent.

Example 3

A scratch-resistant transparent film for a packaging material according to Embodiment 3, comprising a PMMA layer 1 on the upper layer of the film, an APET layer 2 disposed on a lower surface of the PMMA layer 1, and the APET in the The lower surface of the layer 2 is further provided with a PMMA layer 3, the PMMA layer 1 having a thickness of 7% of the total thickness, and the APET layer 2 having a thickness of 86% of the total thickness, the PMMA layer 3 The thickness is 7% of the total thickness, and the total thickness of the film is 3 mm. The preparation method comprises the following steps: drying the PMMA pellets and the APET pellets separately, and conveying them to the co-extrusion sheet unit for extrusion molding; the performance test is as shown in Table 5, and the PETG film material of the same thickness is used as a control, The performance is shown in Table 6. In addition, since the PETG/APET/PETG sheet of the same thickness is thicker than 1 mm, the APET is likely to be crystallized white due to the cooling rate being too slow, which seriously affects the transparency, and is not considered as a comparative example here.

Table 5

Table 6

The above comparison shows that, compared with the PETG/APET/PETG sheet currently on the market, in addition to the cost, the present invention has significantly improved the hardness and scratch resistance of the film, and the heat distortion temperature of the sheet is also increased.

Example 4

Two-layer composite sheet of 0.5mm thick PMMA/APET (thickness ratio: 10:90) is printed, UV-textured, electroplated, coated, hot-pressed, UV-hardened, CNC-finished to make scratch-resistant Phone case.

Compared with the PMMA products of the same thickness, the surface of the mobile phone case of the present embodiment has the same surface hardness, but the material cost is saved by 40% and the impact strength is increased by 2 times. Compared with the mobile phone case made of PMMA/PC two-layer composite sheet (thickness ratio 10:90), the material cost is also saved by 40%, but it will not be stress cracked.

Example 5

A 0.5 mm thick PMMA/CPET/PMMA three-layer composite sheet sheet (thickness ratio 10:80:10) was printed, thermoformed, and UV-hardened to form a scratch-resistant mobile phone case.

Compared with the PMMA article of the same thickness, the surface of the outer casing of the mobile phone of the present embodiment has the same hardness, but the material cost is saved by 36%, and the impact strength is increased by 1.8 times.

In this embodiment, since the intermediate layer is a crystalline CPET layer, the heat distortion temperature is increased by 30 degrees compared to Example 4 in which the inner surface layer of the article is APET.

Compared with the mobile phone case made of PMMA/PC/PMMA three-layer composite sheet (thickness ratio 10:80:10), the material cost of the embodiment is also saved by 36%, but no stress cracking.

Example 6

A UV-hardened layer was applied to the two surface layers with a transparent 0.2 mm thick PMMA/APET/PMMA three-layer composite sheet (thickness ratio 12.5:75:12.5) to form a window panel.

PMMA is extremely fragile due to poor impact resistance and cannot be made into a film of 0.2 mm. However, the structure of this embodiment can produce a film panel with a thickness of 0.2 mm, and the obtained panel is more visible than other PET on the market. The surface hardness of the PC panel is about 10 (R scale), and the scratch resistance is better.

Example 7

Apply a UV hardened layer to the two surface layers with a transparent 0.15mm thick PMMA/APET two-layer composite sheet (thickness ratio 20:80), apply glue on one side and cover the release film, and anti-glare treatment on the other side. Add oleophobic hydrophobic coating to make surface protection film for electronic products such as mobile phones.

Due to its poor impact resistance, PMMA is extremely brittle and cannot be made into a 0.15mm film. The surface protective film of the present embodiment has a surface hardness of about 10 (R scale) or more higher than other visible PET, PC, PP, and PVC protective films on the market, and the scratch resistance is better.

Example 8

A 0.5 mm thick PMMA/APET/PMMA three-layer composite sheet (thickness ratio 10:80:10) was coated with a UV hardened layer and vacuum-aluminized to form a lens.

The surface hardness of the lens of this example was the same as that of the PMMA article of the same thickness, but the material cost was saved by 36% and the impact strength was increased by 1.8 times.

The structure of this embodiment can also produce a thinner lens, but the PMMA of the prior art cannot be fabricated due to the problem of brittle fracture.

The lens of this embodiment has a surface hardness of about 10 (R scale) higher than other visible PET and PC panels on the market, and the scratch resistance is better.

Example 9

The 0.5mm thick PMMA/APET two-layer composite sheet (thickness ratio 10:90) was coated with UV hardened layer and printed to make electronic products or instrument panel and sign.

Compared with PMMA products of the same thickness, the panel and sign of this embodiment have the same surface hardness, but the material cost is saved by 40%, the impact strength is increased by 2 times, and the surface hardness of other visible plastic PET and PC panels is higher than those on the market. About 10 (R scale), better scratch resistance.

The preferred embodiments of the invention disclosed above are merely illustrative of the invention. The preferred embodiments are not to be considered in all detail, and the invention is not limited to the specific embodiments. Obviously, many modifications and variations are possible in light of the teachings herein. The present invention has been chosen and described in detail to explain the embodiments of the invention and the invention. The invention is to be limited only by the scope of the appended claims and the appended claims.

Claims

An anti-scratch transparent film for use in a packaging material, comprising: a PMMA layer on an upper layer of the film; and a PETG or APET layer disposed on a lower surface of the PMMA layer, the thickness of the PMMA layer The total thickness is from 5 to 40%, and the thickness of the PETG or APET layer is from 20 to 95% of the total thickness.
The scratch-resistant transparent film according to claim 1, wherein a PMMA layer is further provided on a lower surface of said PETG or APET layer, the thickness of which is 5 to 40% of the total thickness.
The scratch-resistant transparent film according to claim 1 or 2, wherein the film has a total thickness of 0.1 to 6 mm, preferably 0.1 to 3 mm, more preferably 0.15 to 0.95 mm.
The scratch-resistant transparent film according to claim 1 or 2, wherein when the total thickness of the film is 0.5 mm or less, the ratio of the thickness of the single layer of the PMMA layer to the total thickness is 10-15. %, the ratio of the thickness of the PETG or APET layer to the total thickness is 70 to 90%; when the total thickness of the film is more than 0.5 mm, the ratio of the thickness of the single layer of the PMMA layer to the total thickness is 5 to 10%. The ratio of the thickness of the PETG or APET layer to the total thickness is 80 to 95%.
The scratch-resistant transparent film according to claim 1 or 2, wherein the film has a Rockwell hardness R scale of not less than 110.
The scratch-resistant transparent film according to claim 1 or 2, wherein the film has a light transmittance of more than 86%.
The anti-scratch transparent film according to claim 1 or 2, wherein the PMMA layer contains no or a small amount of PET, and the content of PET ranges from 0 to 50%, preferably from 0 to 40%. Preferably, it is 0 to 30%; the PETG or APET layer contains no or a small amount of PMMA, and the content of PMMA ranges from 0 to 50%, preferably from 0 to 40%, more preferably from 0 to 30%.
The scratch-resistant transparent film according to claim 1 or 2, wherein the PMMA layer and the PETG or APET layer are directly joined together by a co-extrusion process.
A method for preparing a scratch-resistant transparent film according to any one of claims 1 to 8, which comprises extruding PMMA from an extruder and flowing the molten material to the dispenser, PETG or APET is extruded and plasticized from another extruder, and the molten material is also flowed to the dispenser, wherein the PMMA is split into one or two layers of melt stream in the dispenser, one in the dispenser and the PETG or APET layer. The sides or sides are stacked together to form a two-layer or three-layer structure, which is cooled and formed into a solid film after flowing out of the die.
A method for preparing a scratch-resistant transparent film according to any one of claims 1 to 8, which comprises subjecting PMMA to extrusion molding from a first extruder, and flowing the molten material to the dispenser, and PETG or APET is extruded and plasticized from a second extruder. The molten material also flows to the distributor. The PMMA is also extruded and plasticized from the third extruder. The molten material flows to the distributor from the first and third. The extruder extruded PMMA molten material is superposed on both sides of the distributor and the PETG or APET layer to form a three-layer structure, which is cooled and formed into a solid film after flowing out of the die.
A method of producing a scratch-resistant transparent film according to claim 9 or 10, wherein each of the molten materials is not at the dispenser, but is laminated at the die to form a multilayer structure.
A scratch-resistant surface product, characterized in that the scratch-resistant surface product is made of a scratch-resistant composite sheet comprising a PET layer, an upper layer of the PET layer a PMMA layer is provided, and the PMMA layer disposed on the upper layer is used as an outer surface of the scratch-resistant composite sheet, and the thickness of the PMMA layer is 5-40% of the total thickness, and the thickness of the PET layer is It accounts for 20 to 95% of the total thickness.
The scratch-resistant surface article according to claim 12, wherein the PET layer of the scratch-resistant composite sheet is not provided with a lower layer or a lower layer, and in the case where a lower layer is provided, the lower layer is:

PMMA layer, at this time, the scratch-resistant composite sheet has a three-layer structure, referred to as PMMA/PET/PMMA composite sheet; or

PC layer, at this time, the scratch-resistant composite sheet has a three-layer structure, referred to as PMMA/PET/PC composite sheet; or

The PC layer is further provided with a PMMA layer under the PC layer. At this time, the scratch-resistant composite sheet has a four-layer structure, which is referred to as a PMMA/PET/PC/PMMA composite sheet.
The scratch-resistant surface article according to claim 12, wherein the PET layer and the PMMA layer of the scratch-resistant composite sheet are directly compounded by co-extrusion.
The scratch-resistant surface product according to claim 12 or 13, wherein the PET layer of the scratch-resistant composite sheet is amorphous PET, or a crystalline PET to which a nucleating agent is added, or is not crystallized. Copolymerized PET, or a mixture of any two or three of them in any ratio.
The scratch-resistant surface article according to claim 12 or 13, wherein the composite sheet has a total thickness of from 0.1 to 6 mm, preferably from 0.1 to 0.95 mm, more preferably from 0.1 to 0.49 mm.
The scratch-resistant surface product according to claim 12 or 13, wherein when the total thickness of the composite sheet is 0.5 mm or less, the thickness ratio of the lower PMMA layer or the PMMA layer to the PC layer When the total thickness of the composite sheet is more than 0.5 mm, the thickness ratio of the lower PMMA layer or the PMMA layer to the PC layer is 5% to 10%.
The scratch-resistant surface product according to claim 12 or 13, wherein the PET layer of the composite sheet has a PET content of 10% to 100%, preferably 50% to 100%, more preferably 60. From 100% to 100%, more preferably from 70% to 100%, still more preferably from 90% to 100%.
The scratch-resistant surface product according to claim 12 or 13, wherein the PMMA layer of the composite sheet does not contain or contain a small amount of PET, and the content of PET ranges from 0 to 50%, preferably 0 to 40%, more preferably 0 to 30%; the PET layer does not contain or contain a small amount of PMMA, and the content of PMMA ranges from 0 to 50%, preferably from 0 to 40%, more preferably from 0 to 30%.
The scratch-resistant surface product according to claim 12 or 13, wherein the scratch-resistant surface product is prepared by subjecting the scratch-resistant composite sheet to surface hardening, cold stamping, and hot press forming. , or IMD, anti-glare treatment, hydrophobic oleophobic treatment, vacuum evaporation, in-mold labeling, printing, electroplating, one or more processes, to produce a variety of scratch-resistant surface products.
The scratch-resistant surface article according to claim 12 or 13, wherein one or more layers constituting said composite sheet are added with a lubricant, and said lubricant is added to the matrix of each layer.
A scratch-resistant surface article according to claim 12 or claim 13 wherein one or more of the layers comprising the composite sheet are further provided with one or more functional additives.
The scratch-resistant surface article according to claim 12 or 13, wherein said composite sheet has a Rockwell hardness R scale of not less than 110.
A scratch-resistant composite sheet, characterized in that the scratch-resistant composite sheet is the scratch-resistant composite sheet or composite sheet according to any one of claims 12-23.