Standard developing agent as well as preparation method and application thereof

Abstract

The invention provides a standard developing agent. The standard developing agent comprises 40-70 parts of carrier vegetable oil, 1-10 parts of a heat absorption auxiliary agent 1, 10-30 parts of a heat absorption auxiliary agent 2 and 5-20 parts of other auxiliary agents. The carrier vegetable oil is epoxidized soybean oil, refined rapeseed oil, squeezed peanut oil or a mixture thereof; the heat absorption auxiliary agent 1 is titanium nitride, fine carbon black, graphene or a mixture thereof; the heat absorption auxiliary agent 2 is zinc oxide; and the other auxiliary agent is an ultraviolet light absorber, an antioxidant or a mixture thereof. According to the marking agent, the marking efficiency of PET bottles can be effectively improved, meanwhile, the bottle blowing energy consumption of the PET bottles in the bottle blowing process is reduced, the printing definition can be improved, especially the definition of the corner parts of fonts can be improved, and even small fonts and bar codes can be clearly recognized.

Description

Technical Field

[0001] The present invention relates to a label developer, in particular to a label developer for PET bottles, and also relates to a preparation method and application of the label developer. Technical Background

[0002] Traditional beverage bottle packaging consists of three parts: bottle, bottle cap and label. Label is a simple sign used to indicate the name, weight, volume, purpose and other information of the item. However, although the traditional label form has a special functional effect in displaying product information and highlighting product features, it will inevitably cause material loss and increase the cost of screening and separation during the recycling process of beverage bottles.

[0003] Most of the beverage bottles on the market are made of recyclable PET materials, so the recycling of beverage bottles is particularly important. In recent years, many domestic and foreign beverage brands have begun to try to "unlabel" their products. The so-called "unlabel" means that the beverage bottles no longer have labels with brand logos and product information, but use laser printing or inkjet to print the main information of the product directly on the bottle.

[0004] Although laser marking has certain advantages over labeling in the recycling of PET bottles, the technology of laser marking on PET bottles still has limitations. No matter what kind of laser is used for labelless printing, there will be problems such as low printing efficiency, poor contrast, unclear marking content, blurred corners, obvious damage to the bottle wall, and rough touch. At the same time, due to the limitations of the appearance structure of PET bottles, the content around the label can hardly be displayed, and the barcode is difficult to present clearly.

[0005] Patent document CN102070889A discloses a PET resin composition with laser marking function, which includes polyethylene terephthalate, continuous glass fiber, toughening agent, carbon black, nucleating agent, and laser marking additive, wherein the laser marking additive is produced by DSM. The PET resin composition can form white text on the surface of a black product, or black text on the surface of a white product, and other distinct laser marks, but the stability and smoothness of the mark are poor, making it difficult to carry out efficient laser marking, and the mark cannot be retained for a long time.

[0006] Patent document CN109337356A discloses a laser-markable composition, which contains conversion nanoparticles and a photosensitizer. Under the action of laser, the photosensitizer produces a photothermal effect to burn off the black pigment, leaving behind the color pigment, thereby forming a permanent color mark on the marked part. However, the marking process requires the use of specific conversion nanoparticles, the process is difficult, and is not suitable for large-scale industrial production. Summary of the invention

[0007] In order to overcome the defects in the prior art, the present invention provides a label developer. By adding only a small amount of the label developer to the PET substrate, the laser marking effect of the PET bottle can be greatly improved while effectively improving the efficiency of labelless printing, especially for labelless printing with more content and less words, the printing clarity can be improved; in addition, in the process of blowing bottles using the PET substrate added with the label developer, the energy consumption of blowing bottles can be significantly reduced (saving more than 20%), and the appearance of the bottle body is basically not affected. In addition, the purpose of the present invention is to provide a method for preparing a label developer and the application of the label developer in PET bottles.

[0008] The marker developer according to the present invention comprises (by weight):

[0009]

[0010] Among them, the carrier vegetable oil is epoxidized soybean oil, refined rapeseed oil, pressed peanut oil or a mixture thereof; the endothermic additive 1 is titanium nitride, fine carbon black, graphene or a mixture thereof; the endothermic additive 2 is zinc oxide; and other additives are ultraviolet absorbers, antioxidants or a mixture thereof.

[0011] Furthermore, the endothermic auxiliary agent 1 is preferably a mixture of titanium nitride, fine carbon black and graphene.

[0012] Furthermore, in the endothermic auxiliary agent 1 , preferably, the weight of graphene accounts for more than 10 wt % (weight percentage) of the total weight of the endothermic auxiliary agent 1 ; more preferably, the weight of graphene accounts for 10 to 20 wt % of the total weight of the endothermic auxiliary agent 1 .

[0013] Furthermore, the ultraviolet absorber is UV234, UV360, UV3638 or a mixture thereof, and the antioxidant is antioxidant 1010, antioxidant 1076, antioxidant 168, antioxidant 9228 or a mixture thereof.

[0014] The preparation method of the marker developer according to the present invention comprises the following steps:

[0015] (1) dispersing the endothermic aids 1 and 2 and other aids in a carrier vegetable oil according to the amount used, and fully and evenly dispersing them by high-speed stirring to obtain a dispersion; and

[0016] (2) The dispersion is transferred to a grinder, and the particle size of the solid matter contained in the dispersion is controlled within a range of 3 to 5 μm by grinding, thereby obtaining the marker developer.

[0017] Furthermore, the preparation method also includes testing the quality and performance of the finished product of the ground marker developer, and then subpackaging it.

[0018] Furthermore, the grinder is a horizontal grinder.

[0019] Furthermore, the grinding is performed by ball milling.

[0020] According to the present invention, there is also provided the use of the above-mentioned label developer in PET bottles.

[0021] Furthermore, the PET bottle comprises a PET substrate and the label developer, wherein the contents of the components (by weight percentage) are respectively:

[0022] PET substrate 99.80 to 99.95wt%,

[0023] The content of the marker is 0.05 to 0.20 wt%.

[0024] Furthermore, the intrinsic viscosity of the PET substrate is 0.7 to 0.9 dL / g.

[0025] The method for preparing a PET bottle according to the present invention comprises the following steps:

[0026] (1) drying the PET substrate particles in a dehumidifying dryer for at least 5 hours;

[0027] (2) adding the liquid developer to the dried PET substrate particles according to the aforementioned ratio;

[0028] (3) injection molded preforms; and

[0029] (4) Heating and blowing the bottle to obtain a finished PET bottle.

[0030] The present invention uses vegetable oil as a carrier and two different heat-absorbing additives as important components of the marking agent. During the laser processing of materials, laser marking is formed through a thermal process. Here, laser processing is essentially the interaction between laser and matter, specifically when the laser beam is projected onto the surface (or inside) of a material, part of the energy of the laser beam is reflected, absorbed and / or transmitted, wherein the light energy is absorbed in the form of vibration excitation of electrons and atoms, and energy transfer and transmission occur, thereby causing various physical and / or chemical effects and processes.

[0031] The heat absorbing auxiliary agent 1 used in the present invention is titanium nitride, fine carbon black, graphene or a mixture thereof. Such heat absorbing auxiliary agent 1 can effectively absorb heat energy and quickly conduct the heat energy to the inner wall of the preform. The rapid absorption of light is beneficial to the effect and efficiency of laser marking. The specific working principle is: near the wavelength of 1100 nanometers, the absorption of PET (polyethylene terephthalate) resin has a weak value, while titanium nitride, fine carbon black, graphene or a mixture thereof can effectively absorb heat energy in the wavelength range of 1100 nanometers, thereby improving the absorption of heat energy when the preform is heated by a near-infrared lamp before blowing the bottle, and can effectively increase the radiation of near-infrared rays to compensate for the weak infrared absorption performance of PET itself. Graphene has extremely high thermal conductivity, and its orderly stacked structure can make full use of thermal energy during heat conduction. However, pure graphene has problems such as uneven dispersion and interface effect. Therefore, using it together with other heat-absorbing materials is a better choice. The inventors of the present invention creatively discovered that when the weight of graphene is 10 to 20wt% of the total weight of the heat-absorbing auxiliary agent 1, the maximum heat energy absorption efficiency can be achieved, and the interface effect will not have an adverse effect on heat conduction.

[0032] The endothermic auxiliary agent 2 used in the present invention is zinc oxide. Zinc oxide with a hexagonal wurtzite structure can generate a concentration difference between holes and electrons due to the thermal motion of electrons inside the material at a certain temperature, thereby generating a thermoelectric potential difference. This is called the pyroelectric effect or the thermoelectric effect, that is, the current or charge accumulation phenomenon generated when the electrons in the heated object move from the high temperature zone to the low temperature zone along the temperature gradient. When the laser marking equipment generates thermoelectric potential by focusing radiation on the above-mentioned endothermic auxiliary agent, a certain thermoelectric effect will be generated, thereby improving the burning carbonization effect on the bottle wall surface during marking, forming a dense and deep burning carbonization mark, making the laser printing effect more prominent and the handwriting more obvious.

[0033] The heat absorbing additives 1 and 2 work together to further improve the heat conduction and thermal effect during the laser marking process, achieving higher marking clarity.

[0034] Beneficial effects of the present invention:

[0035] 1. The use of titanium nitride, fine carbon black, graphene or a mixture thereof and zinc oxide as heat-absorbing additives in the marking agent according to the present invention can make full use of the thermal effect occurring during the laser marking process and enhance the efficiency of laser carbonization and heat conduction. The color development effect of the PET bottle with the marking agent added is significantly improved, and the marking content is clearer and more efficient, especially in the corners of the fonts. The marking handwriting is uniform and beautiful, and the barcode and QR code are clear and can be accurately recognized. At a marking speed of 3000 to 8000 mm / s, clear patterns and words can be presented.

[0036] 2. The use of heat absorbing auxiliary agent in the label developer according to the present invention can also improve the bottle blowing efficiency, and the energy consumption of bottle blowing is significantly reduced (the maximum heat absorption efficiency can exceed 20%), which greatly reduces energy loss and carbon emissions.

[0037] 3. By controlling the content of graphene in the endothermic auxiliary agent 1 according to the present invention to 10-20wt%, the thermal effect of graphene can be maximized. The graphene at this amount enables the effect of the marker developer to be effectively exerted, and the appearance and performance of the PET bottle will not be adversely affected by negative effects such as the interface effect of graphene.

[0038] 4. In the technical solution of the present invention, the particle size of the solid matter contained in the developer is controlled within the range of 3 to 5 μm by ball milling, which can ensure the stability of the effect of the developer. On the one hand, the resolution clarity of the marked content is improved, and on the other hand, the marked content is given a long-lasting smooth effect, which will not fade easily due to external factors such as friction and temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 A schematic diagram of a device for adding a developer to PET particles and a related PET bottle preparation device;

[0040] FIG. 2( a ) and FIG. 2( b ) are schematic diagrams showing the results of marking a PET bottle with and without the addition of a 0.1 wt % marking agent, respectively;

[0041] Figure 3(a) to Figure 3(c) It is a comparison diagram of the effects of adding Examples 1-8 and blank test bottles at different marking speeds, wherein Figure 3(a) corresponds to Examples 1-3, Figure 3(b) corresponds to Examples 4-6, and Figure 3(c) corresponds to Examples 7-8 and pure PET bottles.

[0042] List of reference numerals:

[0043] 1001: Equipment for adding developer;

[0044] 1002: marker developer;

[0045] 1003: Hopper;

[0046] 1004: premixer;

[0047] 1005: feeding port;

[0048] 1006: driving device;

[0049] 1007: Injection molding screw. DETAILED DESCRIPTION

[0050] Figure 1The schematic diagram of the equipment for adding the developer to the PET particles and its related PET bottle production equipment is shown. Figure 1 In the device shown, the addition of the labeling agent 1002 is consistent with the conventional liquid additive addition method, that is, the labeling agent adding device 1001 is used to add the plastic particles in the hopper 1003 to the injection molding screw 1007, and the labeling agent is added quantitatively according to the addition amount required for each production cycle through automatic signal control, so that effective dispersion and mixing can be performed in the injection molding screw 1007 driven by the driving device 1006. Figure 1 As shown, a premixer 1004 may also be installed at the inlet 1005 of the injection molding machine to enhance stirring and mixing, so that the marking agent and the plastic particles are better mixed, thereby improving the use effect of the marking agent 1002.

[0051] The following is a clear and complete description of the technical solution according to the present invention in conjunction with the embodiments. Obviously, the embodiments described below are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments recorded in the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0052] Synthesis Example 1, Preparation of marker developing agent 1:

[0053] (1) 3 parts of titanium nitride, 1 part of fine carbon black, 1 part of graphene, 20 parts of zinc oxide, and 5 parts of ultraviolet absorber UV3638 were dispersed in 60 parts of epoxidized soybean oil, and the mixture was fully and uniformly dispersed by high-speed stirring at a speed of 1000 rpm to obtain a dispersion;

[0054] (2) The dispersion is transferred to a grinder, such as a clean horizontal grinder; the particle size of the solid matter contained in the dispersion is controlled within a range of 3 to 5 μm by grinding, such as by ball milling; and the ground finished product is then tested for quality and performance. After passing the test, it is packaged to obtain the developer 1.

[0055] Synthesis Example 2, Preparation of marker developing agent 2:

[0056] (1) dispersing 4 parts of titanium nitride, 1 part of graphene, 20 parts of zinc oxide, and 5 parts of ultraviolet absorber UV3638 in 60 parts of epoxidized soybean oil, and fully and uniformly dispersing them by high-speed stirring at a stirring speed of 1000 rpm to obtain a dispersion;

[0057] (2) The dispersion is transferred to a grinder, and the particle size of the solid matter contained in the dispersion is controlled within a range of 3 to 5 μm by grinding; the finished product is then tested for quality and performance, and after passing the test, it is packaged to obtain the developer 2.

[0058] Synthesis Example 3, Preparation of marker developer 3:

[0059] (1) Dispersing 4 parts of fine carbon black, 1 part of graphene, 20 parts of zinc oxide, and 85 parts of ultraviolet absorber UV363 in 60 parts of epoxidized soybean oil, and fully and uniformly dispersing them by high-speed stirring at a stirring speed of 1000 rpm to obtain a dispersion;

[0060] (2) The dispersion is transferred to a grinder, and the particle size of the solid matter contained in the dispersion is controlled within a range of 3 to 5 μm by grinding; the finished product is then tested for quality and performance, and after passing the test, it is packaged to obtain the developer 3.

[0061] Synthesis Example 4, Preparation of marker developer 4:

[0062] (1) 4 parts of titanium nitride, 1 part of fine carbon black, 20 parts of zinc oxide, and 385 parts of ultraviolet absorber UV36 were dispersed in 60 parts of epoxidized soybean oil, and the mixture was fully and uniformly dispersed by high-speed stirring at a speed of 1000 rpm to obtain a dispersion;

[0063] (2) The dispersion is transferred to a grinder, and the particle size of the solid matter contained in the dispersion is controlled within the range of 3 to 5 μm by grinding; the finished product is then tested for quality and performance, and after passing the test, it is packaged to obtain the developer 4.

[0064] Synthesis Example 5, Preparation of marker developing agent 5:

[0065] (1) 3 parts of titanium nitride, 1 part of fine carbon black, 2 parts of graphene, 20 parts of zinc oxide, and 5 parts of ultraviolet absorber UV3638 were dispersed in 60 parts of epoxidized soybean oil, and the mixture was fully and uniformly dispersed by high-speed stirring at a speed of 1000 rpm to obtain a dispersion;

[0066] (2) The dispersion is transferred to a grinder, and the particle size of the solid matter contained in the dispersion is controlled within the range of 3 to 5 μm by grinding; the finished product is then tested for quality and performance, and after passing the test, it is packaged to obtain the developer 5.

[0067] Synthesis Example 6, Preparation of Marker 6:

[0068] (1) 3 parts of titanium nitride, 1 part of fine carbon black, 0.3 parts of graphene, 20 parts of zinc oxide, and 5 parts of ultraviolet absorber UV3638 were dispersed in 60 parts of epoxidized soybean oil, and the mixture was fully and uniformly dispersed by high-speed stirring at a speed of 1000 rpm to obtain a dispersion;

[0069] (2) The dispersion is transferred to a grinder, and the particle size of the solid matter contained in the dispersion is controlled within the range of 3 to 5 μm by grinding; the finished product is then tested for quality and performance, and after passing the test, it is packaged to obtain the developer 6.

[0070] Synthesis Example 7, Preparation of marker developer 7:

[0071] (1) 3 parts of titanium nitride, 1 part of fine carbon black, 1 part of graphene, 20 parts of zinc oxide, and 5 parts of ultraviolet absorber UV3638 were dispersed in 60 parts of epoxidized soybean oil, and the mixture was fully and uniformly dispersed by high-speed stirring at a speed of 1000 rpm to obtain a dispersion;

[0072] (2) The dispersion is transferred to a grinder, and the particle size of the solid matter contained in the dispersion is controlled within the range of 6 to 8 μm by grinding; the finished product is then tested for quality and performance, and after passing the test, it is packaged to obtain the developer 7.

[0073] Synthesis Example 8, Preparation of Marker Developing Agent 8:

[0074] (1) 3 parts of titanium nitride, 1 part of fine carbon black, 1 part of graphene, 20 parts of zinc oxide, and 5 parts of ultraviolet absorber UV3638 were dispersed in 60 parts of epoxidized soybean oil, and the mixture was fully and uniformly dispersed by high-speed stirring at a speed of 1000 rpm to obtain a dispersion;

[0075] (2) The dispersion is transferred to a grinder and ground briefly to obtain a solid particle size within a range of 8 to 10 μm; the finished product is then tested for quality and performance, and after passing the test, it is packaged to obtain the developer 8.

[0076] Example 1

[0077] In this embodiment, a label developer 1 and a PET substrate are selected, the PET substrate particles are dried in a dehumidifying dryer for at least 5 hours, and the liquid label developer 1 is added to the dried PET substrate particles at a ratio of 0.1 wt %. The characteristic viscosity of the PET substrate particles is 0.8 dL / g. A bottle embryo is injection molded and heated for blow molding to obtain a PET bottle according to this embodiment 1.

[0078] Laser marking of the PET bottle according to the first embodiment includes the following steps: focusing the laser on the bottle to be laser marked, scanning the corresponding route according to the required mark, and causing the surface of the bottle passing through the scanning route to change color due to the radiation of the laser of a specific wavelength emitted by the laser, thereby forming a mark. In this embodiment, the scanning speed is set to 4000mm / s, and the laser marking equipment is the fiber laser marking machine HANS20Y (20W) of Shenzhen Han's Laser.

[0079] Examples 2 to 8

[0080] In Examples 2 to 8, developer 2 to 8 are used to replace developer 1 in Example 1, respectively, and other process steps remain the same as in Example 1, thereby preparing corresponding PET bottles, and laser marking is performed on the PET bottles according to these examples.

[0081] The marking effects according to Examples 1 to 8 are shown in Figure 1, wherein the marking area is visually evaluated to see whether the lines are smooth and clear and whether the fonts are complete and smooth.

[0082] Table 1:

[0083]

[0084] The above test results clearly show that under the same marking conditions, compared with the bottle without adding the marking developer, by adding the marking developer according to the present invention, the marking content is clearer, the handwriting is more uniform and beautiful, especially the corner part of the font, even the smaller font is clear and beautiful, as shown in the left sub-figure of Figure 2 of the specification (wherein 0.1wt% of the marking developer 1 is added). It can better highlight the quality and beauty of the product logo, and the barcode is clear and recognizable. In particular, according to Table 1 above, it can be clearly seen that the marking developer with an appropriate amount of graphene has excellent performance in terms of clarity, smoothness and marking effect. However, the pure PET bottle without the marking developer according to the present invention is obviously relatively blurred in the marking, the text content or pattern around the label can hardly be displayed, and the barcode is difficult to present clearly, as shown in the right sub-figure of Figure 2 of the specification (wherein no marking developer is added).

[0085] In addition, the addition of the developer not only improves the marking effect, but also further improves the marking efficiency. In order to more intuitively observe and compare the marking efficiency, PET bottles manufactured according to Examples 1 to 8 of the present invention and a blank experimental bottle (i.e., a pure PET bottle without the developer added) were selected to perform laser marking tests at marking rates of 3000 mm / s to 8000 mm / s. The marking results are shown in FIG. Figure 3(a) to Figure 3(c) As shown, bottles 1 to 8 correspond to Examples 1 to 8 respectively, and bottle 9 corresponds to a blank test bottle.

[0086] The experimental results show that the PET bottle added with the developer according to the present invention can still present clear fonts and patterns even when the marking speed reaches 8000mm / s. However, the marking of pure PET bottles without developer can only keep the words relatively clear at a marking speed of 3000mm / s, and as the marking speed is further increased, the marking results are completely unacceptable.

[0087] In addition, the inventors also found that in the process of blowing bottles, the energy consumption when using a PET substrate added with a label developer according to the present invention for blowing bottles is significantly lower than when using a PET substrate without a label developer, and the appearance of the bottle body is basically not adversely affected. In view of this, the following method is used for verification: in the process of heating the preform, the rated power of the heating lamp box in the preform feeding section, the stabilization section and the heat dispersion section in the oven is adjusted, and the total power change of the bottle blowing machine is checked under a relatively stable heating and blowing state. The comparison of the energy consumption of blowing bottles according to Examples 1 to 8 and the blank experimental bottles is shown in Table 2 below:

[0088] Table 2

[0089]

[0090]

[0091] The test results show that when using a PET substrate with 0.1wt% of a developer added for bottle blowing, the energy consumption is reduced by more than 20%, and the energy consumption of manufacturing a PET bottle according to Example 1 is reduced by 27% compared with the energy consumption of manufacturing a pure PET bottle. The main reason for this result is that under the combined action of titanium nitride, fine carbon black, graphene, and zinc oxide in the heat absorption auxiliary agent, the heat absorption effect of the PET substrate is improved as a whole, thereby improving the heat absorption efficiency. In particular, with the help of the ultra-high thermal conductivity of graphene, the combined action of graphene, titanium nitride, and fine carbon black maximizes the efficiency of the system's heat energy absorption, thereby significantly reducing the energy consumption of bottle blowing.

[0092] The above examples are only some embodiments according to the present invention, and are not intended to limit the present invention to the scope of these examples. In fact, any modification, equivalent substitution, improvement, etc. made without departing from the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A marker developer, characterized in that: It includes the following components by weight: Among them, the carrier vegetable oil is epoxidized soybean oil, refined rapeseed oil, pressed peanut oil or a mixture thereof; the endothermic auxiliary agent 1 is titanium nitride, fine carbon black, graphene or a mixture thereof; the endothermic auxiliary agent 2 is zinc oxide; and the other auxiliary agents are ultraviolet absorbers, antioxidants or a mixture thereof.

2. The marker developer according to claim 1, characterized in that: The endothermic auxiliary agent 1 is a mixture of titanium nitride, fine carbon black and graphene.

3. The marker developer according to claim 2, characterized in that: The weight of the graphene accounts for more than 10 wt % of the total weight of the endothermic auxiliary agent 1 .

4. The marker developer according to claim 3, characterized in that: The weight of the graphene accounts for 10 to 20 wt % of the total weight of the endothermic auxiliary agent 1 .

5. The marker developer according to any one of claims 1 to 4, characterized in that: The ultraviolet absorber is UV234, UV360, UV3638 or a mixture thereof; the antioxidant is antioxidant 1010, antioxidant 1076, antioxidant 168, antioxidant 9228 or a mixture thereof.

6. A method for preparing a marker developer according to any one of claims 1 to 5, characterized in that: The following steps are involved: (1) dispersing endothermic aid 1, endothermic aid 2 and other additives in a carrier vegetable oil according to the amount used, and fully and evenly dispersing them by high-speed stirring to obtain a dispersion; (2) The dispersion is transferred to a grinder, and the particle size of the solid matter contained in the dispersion is controlled within a range of 3 to 5 μm by grinding, thereby obtaining the marker developer.

7. The preparation method according to claim 6, characterized in that: The method also includes the steps of testing the quality and performance of the finished product of the ground marker developer and then packaging it.

8. The preparation method according to claim 6 or 7, characterized in that: The grinder is a horizontal grinder.

9. The preparation method according to claim 6 or 7, characterized in that: The grinding is performed by ball milling.

10. Use of the label developer according to any one of claims 1 to 5 or the label developer manufactured by the preparation method according to any one of claims 6 to 9 in PET bottles.

11. The use according to claim 10, characterized in that: The PET bottle comprises a PET substrate and a label developer according to any one of claims 1 to 5 or a label developer manufactured by the preparation method according to any one of claims 6 to 9, wherein the contents of each component by weight percentage are respectively: PET substrate 99.80 to 99.95wt%, The content of the marker is 0.05 to 0.20 wt%.

12. The use according to claim 11, characterized in that: The intrinsic viscosity of the PET substrate is 0.7 to 0.9 dL / g.

13. A method for preparing a PET bottle, characterized in that: The following steps are involved: (1) drying the PET substrate particles in a dehumidifying dryer for at least 5 hours; (2) adding the marking agent according to any one of claims 1 to 5 or the marking agent produced by the preparation method according to any one of claims 6 to 9 to the dried PET substrate particles in proportion; (3) injection molded preforms; and, (4) heating and blowing the bottle to obtain the PET bottle.

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