CN117186463A

CN117186463A - Sulfur-based material-based laser high-sensitivity film, and preparation method and application thereof

Info

Publication number: CN117186463A
Application number: CN202311479195.8A
Authority: CN
Inventors: 陈煜�; 王新文; 王钦华; 任振伟
Original assignee: Suzhou University
Current assignee: Suzhou University
Priority date: 2023-11-08
Filing date: 2023-11-08
Publication date: 2023-12-08

Abstract

The invention belongs to the field of laser marking, and particularly relates to a sulfur-based material laser high-sensitivity film, and a preparation method and application thereof. Use is made of particulate or powdery high molecular polymers, powdery chalcogenide materials, toughening agents, lubricants and antioxidants. The high molecular polymer and additives such as powdery chalcogenide material, toughening agent, antioxidant and the like are premixed through high-speed mixing equipment, melted, mixed and extruded to form granules, and the modified high molecular material is prepared. The prepared uniformly mixed high molecular polymer particles are prepared into a film by a tape casting method, wherein the film contains a laser absorbent. The film can overcome the defects of the traditional marker, such as easy damage, poor water and oxygen resistance and the like. The laser high-sensitive film has the capabilities of high-precision recording and high-speed recording, can be applied to different surface shapes of various objects, and has the advantage that the recording is not easy to eliminate compared with the recording based on hot stamping and an ink-jet mode.

Description

Sulfur-based material-based laser high-sensitivity film, and preparation method and application thereof

Technical Field

The invention belongs to the field of laser marking, and particularly relates to a chalcogenide material-based laser high-sensitivity film, and a preparation method and application thereof.

Background

In recent years, there has been an increasing social demand for surface-decorative plastic articles. However, the conventional decoration methods such as painting, ink marking and screen printing are not only cumbersome in operation but also accompanied by serious environmental problems. The chemical additives and chemical reactions used in these conventional methods can lead to the generation of large amounts of toxic and harmful substances on the surface of the plastic, thereby limiting the range of applications of the product.

Fortunately, laser marking techniques can effectively solve this problem. Laser marking techniques have many advantages over traditional methods, including more environmental protection, higher precision, longer lasting, shorter manufacturing cycles, more flexibility, contactless handling, etc.

The principle of laser marking is to absorb and convert laser energy into heat energy, thereby triggering various physical and chemical changes inside the polymer matrix and realizing marking effect. For example, some polymers such as polyethylene terephthalate, polybutylene terephthalate, and polystyrene are easily carbonized under laser irradiation, and are suitable for dark marks. On the other hand, polymers such as polyoxymethylene foam easily foam under laser irradiation, and are suitable for laser marking.

Hitherto, many plastics have been proven, for example Polycarbonate (PC), polyethylene (PE), polypropyleneThe marking of olefins (PP), polyamides (PA), polymethyl methacrylate (PMMA), polyoxymethylene (POM), polyurethane (PUR), polyesters is difficult or even impossible with lasers. CO emitting in the infrared region with a wavelength of 10.6 microns ₂ Lasers produce only weak, hardly identifiable marks on the polyolefin even at very high output levels, since the absorption coefficient of the plastic to be processed is not high enough to cause a colour change of the polymeric material at the above-mentioned wavelengths. The plastic must not fully reflect or transmit the laser light because no interaction occurs if so. However, it must also not be strongly absorbent, since in this case the plastic evaporates leaving only the engraving. The laser beam is absorbed, causing an interaction with the material depending on the chemical structure of the plastic and the wavelength of the laser used.

To improve the laser marking effect, the laser power and irradiation time may be increased, but this also increases the cost. Thus, the addition of laser sensitive additives to polymers, including mica, bismuth oxide, chlorinated bismuth oxide, tin oxide, titanium dioxide, and the like, is a simple and effective method. The additives can effectively absorb laser energy to enable the surrounding polymer matrix to generate carbonization reaction, so that the surface marking with high definition, high contrast and no damage is realized. CN 1169677C describes a laser markable plastic that allows the modified plastic to be marked by laser by adding a photosensitive pigment to the plastic base that was otherwise difficult to mark with laser.

CN 115536943A describes a laser markable polypropylene plastic that is made to have laser markable properties by adding a laser absorber such as mica flakes, copper oxide or antimony trioxide to the polypropylene plastic.

CN 105085944A describes a special material for laser marking thermoplastic polyurethane, and provides a high-efficiency special material for laser marking thermoplastic polyurethane prepared by adopting a compound inorganic powder coated with a high-molecular dispersing agent and a carbon forming agent, which solves the problems of dispersion and marking limitation.

CN 111440428A describes a polycarbonate-based laser marking composite material and a preparation method thereof, which solves the problem that the marking effect is affected by uneven composition distribution in the existing polycarbonate-based laser marking material by adding one or more of laser absorbents such as metal powder, metal oxide, metal complex and metal complex into polycarbonate plastic.

CN 101717566A describes a method for manufacturing a film and a sheet of polycarbonate marked by laser, wherein a powdery polycarbonate base material, laser powder and an auxiliary agent are mixed in a high-speed mixer, the laser powder is calcined powder composed of tin oxide and antimony oxide, the calcined powder is extruded by a double screw and then pelletized, and the obtained resin particles are manufactured into the film or the sheet by a professional film-making production line, and the obtained product also has the performance of laser marking.

CN 109796678A describes a polymer composition containing a temperature-sensitive substance and capable of being marked by laser color and a preparation method thereof, wherein a high molecular polymer (such as polyethylene, polypropylene, polycarbonate and the like), a laser absorber (such as carbon black, melanin, black ferric oxide, boron nitride) and a temperature-sensitive substance (such as lead, nickel, chromium, zinc, oxide or sulfide) are melt blended to form the polymer composition capable of generating different colors under laser irradiation, so that the problem of color marking on a plastic substrate is solved. However, the color of the temperature sensing substance adopted by the laser marking device is different from that of the laser absorbent, so that the color of the finished product is unevenly distributed, the color of the temperature sensing substance is close to that generated by the laser marking, and the contrast ratio is not obvious enough.

CN2023108121501 describes that the purpose of laser marking is achieved by using a two-dimensional nitride material as a laser absorber, and that most of high molecular polymers without marking effect under laser marking are combined with nitrides with a two-dimensional layered structure, and re-granulated under high temperature melting, and then made into a film, thereby achieving the effect of high-sensitivity laser marking. However, the two-dimensional nitride material with a partial layered structure is expensive, so that the whole cost of the film capable of being marked by laser is high, and the film is difficult to popularize and use.

Disclosure of Invention

In the prior art, some common polymers, such as polyethylene, polypropylene, polycarbonate and Thermoplastic Polyurethane (TPU), have low absorption efficiency on the laser beam with the wavelength of 1064 and nm, and have no obvious physical and chemical changes on the surface of the material after laser irradiation, so that the polymers are difficult to be applied in a large scale in the laser marking field.

In order to improve the laser absorption performance of part of high polymer materials, the application aims to find one or more dopants which enable high polymer such as polycarbonate to be well marked by laser, and high polymer products or films such as polycarbonate doped with the dopants can obtain high-contrast laser marking when being irradiated by laser.

In order to solve the technical problems, the application provides the following technical scheme:

the application provides a preparation method of a laser high-sensitivity film based on a chalcogenide material, which comprises the following steps:

s11: mixing a high molecular polymer, a toughening agent, an antioxidant, a lubricant and a powdery compound to obtain a mixture; the powdery compound is one or two of sulfide and selenide, and the high molecular polymer is particles or powder;

S12: extruding the mixture, cooling and shearing to obtain plastic particles;

s13: and drying, casting or vulcanizing the plastic particles to form a film, thereby obtaining the laser high-sensitivity film based on the chalcogenide material.

Preferably, the mass ratio of the high molecular polymer to the powdery compound is 1000:5-30.

Preferably, the mass ratio of the high molecular polymer to the toughening agent is 1000:50-100.

Preferably, the mass ratio of the high molecular polymer to the antioxidant is 1000:20-40.

Preferably, the mass ratio of the high molecular polymer to the lubricant is 1000:1-20.

Preferably, the material premixing machine employs a high speed mixer.

Preferably, the extrusion is performed using a twin screw plastic extruder.

Further, the temperature of the twin-screw plastic extruder is set to 185 ℃,205 ℃,210 ℃,220 ℃ and 230 ℃ respectively, wherein the temperature of the twin-screw plastic extruder is 5 temperature areas, and the temperature of different high-molecular polymers is selected according to practical conditions.

Preferably, the selected high molecular polymer is selected from one or more of polycarbonate, polyethylene, polyvinyl chloride, polystyrene, polytetrafluoroethylene, polypropylene, polyethylene terephthalate, MABS (methyl methacrylate-acrylonitrile-butadiene-styrene plastic), polymethyl methacrylate, polyamide, polyester, polyphenylene oxide and polyurethane.

Further, the high molecular polymer is selected from one or more of polycarbonate, polyethylene terephthalate, polyvinyl chloride, polystyrene and polypropylene.

Preferably, the toughening agent is selected from a rubber elastomer toughening agent, a polymer toughening agent or a thermoplastic elastomer toughening agent.

Further, the rubber elastomer toughening agent is selected from styrene butadiene rubber, ester rubber or nitrile butadiene rubber; the polymer toughening agent is selected from polyamide toughening agents, polysiloxane or polyurethane toughening agents; the thermoplastic elastomer toughening agent is selected from SBS (styrene-butadiene-styrene block copolymer), SEBS (linear triblock copolymer with polystyrene as a terminal block and ethylene-butene copolymer obtained by hydrogenation of polybutadiene as a middle elastic block), POE (polyolefin thermoplastic elastomer), TPO (thermoplastic polyolefin), MBS polymer (methyl methacrylate-butadiene-styrene) or TPV (thermoplastic vulcanized rubber).

Preferably, the sulfide is selected from one or more of molybdenum disulfide, tungsten disulfide, titanium disulfide, cobalt disulfide, cuprous sulfide, zinc sulfide, platinum sulfide, vanadium sulfide, silver sulfide, chromium sulfide, cadmium sulfide, nickel sulfide and indium sulfide; the selenide is selected from one or more of tungsten diselenide, molybdenum diselenide, copper diselenide, zinc diselenide and silver diselenide.

Further, the powdered compound is selected from molybdenum disulfide, tungsten diselenide, or molybdenum diselenide.

Further, the particle size of the powdery compound is 0.1-100 μm.

Preferably, the antioxidant is selected from phenolic antioxidants, sulfurized phenolic antioxidants or organosilicon antioxidants.

Further, the antioxidant is selected from the group consisting of polyphenol antioxidant 1010, monophenol antioxidant BHT (2, 6-di-tert-butyl-p-cresol), monophenol antioxidant 2246 and bisphenol A antioxidant.

Preferably, the lubricant is selected from the group consisting of ester lubricants, wax lubricants, silicone oils, phenolic resins, organic phosphate lubricants.

Further, the lubricant is selected from polyethylene wax (PEW), polypropylene wax (PPW), polytetrafluoroethylene wax (PTFE), phenolic resin or pentaerythritol stearate (PETS).

Preferably, in step S12, the cooling mode is water cooling tank cooling.

Preferably, the shearing method is to use a granulator for granulating.

Preferably, in the step S13, the drying time is 4-6 h.

Further, the temperature of drying was 110 ℃.

Preferably, in the step S13, the thickness of the cast or vulcanized film is 90-110 μm.

The invention also provides the chalcogenide material-based laser high-sensitivity film prepared by the preparation method.

The invention also provides an application of the chalcogenide material-based laser high-sensitivity film in laser marking, which comprises the following steps:

s21: cutting the laser high-sensitivity film based on the chalcogenide material to obtain a high-molecular polymer film;

s22: and marking the high polymer film under laser to finish the laser marking.

Preferably, the laser is a fiber laser, the laser power is 10-50W, and the laser scanning speed is 500mm/s.

In order to overcome the defects of the traditional marker, such as easy damage of the marker, poor resistance of the marker to water and oxygen, and the like, the invention aims to develop a novel chalcogenide-based laser high-sensitivity film which is doped with a sulfide photosensitizer, a toughening agent, an antioxidant lubricant and a heat stabilizer, and the film can obtain high-contrast laser marker when being irradiated by laser. Compared with common laser absorbers such as metal particle powder and metal oxide materials, the sulfide material photosensitizer has the following advantages:

the chalcogenide material has better heat conduction performance, good laser absorptivity, and the doped and modified high polymer material is more easily marked by laser, so that the obtained mark is not easy to damage; and the cost of part of chalcogenide is low, which is favorable for the wide application of laser marking materials.

The present invention provides laser markable plastics that contain one or more inherently markable dopants having a particle size of 0.1 to 100 microns.

Compared with the prior art, the technical scheme of the invention has the following advantages:

1. overcomes the defects of the traditional marker, such as easy damage of the marker, poor resistance of the marker to water and oxygen, and the like;

2. high-precision recording can be performed;

3. high-speed recording can be performed;

4. recording can be performed on various surface shapes of the object;

5. the laser marking method has an advantage that it is a recording that can be hardly erased as compared with a recording by a hot stamping method or an inkjet method.

Drawings

FIG. 1 is a photograph of polycarbonate in an example.

Fig. 2 is a photograph of tungsten disulfide in the example.

FIG. 3 is a photograph of the modified polycarbonate of example 1 after pelletization and shearing by an extruder.

FIG. 4 is a photograph of the laser marked film of example 1.

Fig. 5 is a picture of the film after changing the laser power in example 1.

Fig. 6 to 8 are pictures of the laser-marked film of example 2.

Fig. 9 is a picture of the thin film after the laser power was changed in example 2.

Fig. 10 is a picture of the thin film after the laser power was changed in example 3.

Fig. 11 is a picture of the film after changing the laser power in example 6.

Fig. 12 is a photograph of the thin film after changing the laser power in example 9.

Fig. 13 is an effect diagram of comparative example 6 after marking under a fiber laser.

Fig. 14 is an effect diagram of example 2 after marking under a fiber laser.

Detailed Description

The present invention will be further described with reference to the accompanying drawings and specific examples, which are not intended to be limiting, so that those skilled in the art will better understand the invention and practice it.

In the embodiment of the invention, only a part of the combination of the high polymer and the laser photosensitizer is introduced, the additive does not influence the effect of the laser photosensitizer, and the rest accords with the analogy embodiment of the combination in the patent specification.

Examples 1-15 compare the laser marking effect of high molecular weight polymer films doped with different amounts of powdered compounds. The materials used in the examples and comparative examples were purchased as follows: polycarbonate (PC) was purchased from Jiangsu Xin New Material Co., ltd; polymethyl methacrylate (PMMA) is purchased from Shanghai plastic international trade company, inc.; polyethylene (PE) is purchased from Shanghai, a source plasticization technology company, inc; polypropylene (PP) is purchased from synfatic metallocene source plastics limited; polystyrene (PS) was purchased from synfatic metallocene source plastics limited; powdered tungsten disulfide, molybdenum disulfide, tungsten diselenide, molybdenum diselenide, tin dioxide, and silver sulfide are purchased from aladine biochemical technologies, inc; the brand of the toughening agent MBS polymer is Japanese Belgium source M722, which is purchased from Ding Xin plastic raw materials limited company in Dongguan city; the polyphenol antioxidant 1010 is purchased from mikrin biochemical technology limited company; the brand of the lubricant pentaerythritol stearate (PETS) is Japan, and is purchased from Guangzhou City Shunfan New Material Co., ltd; antimony trioxide and tin dioxide were purchased from aladine Biotechnology Co. The high-speed mixer, twin-screw extruder and casting machine used in the experiment were purchased from Zhang Jiang Lingjiang mechanical Co.

Example 1

Taking 1kg of polycarbonate particles, 3g of powdery tungsten disulfide, 3g of powdery molybdenum disulfide, 50g of a toughening agent MBS polymer, 1010 g of an antioxidant polyphenol antioxidant and 20g of a lubricant pentaerythritol stearate (PETS); premixing was performed with a high-speed mixer at 4000rpm for 30min.

Adding the mixed PC particles into a double-screw plastic extruder; the temperature of 5 temperature areas of the extruder is set to 185 ℃,205 ℃,210 ℃,220 ℃ and 230 ℃, the temperature of a machine head is set to 240 ℃, extrusion is carried out after the temperature of the extruder is stable, the rotating speed of a screw is set to 320rpm, the extruded PC in the shape of cylindrical thin strips is pulled to be cooled by a water cooling tank, moisture is sucked by a vacuum pump, and then the extruded PC is cut into granules by a granulator.

The resulting pellets were dried in a dryer at 110℃for 5 hours to ensure removal of water from the polycarbonate which would otherwise affect the quality of the subsequent film formation. And (3) putting the dried PC particles into a plastic casting machine, wherein the casting machine adopts a four-temperature-zone heating casting machine, the temperature during melting is adjusted to 216 ℃, 252 ℃, 263 ℃ and 252 ℃, and the rotating speed of the casting machine is set to 23rpm. Cutting the edge of the film cast by the casting machine to ensure that the flatness of the obtained film reaches the required requirement, and forming a film by the casting machine, wherein the thickness of the obtained PC film is 100 micrometers, the width of the PC film is 10cm, and the PC film is light black.

The obtained PC film is marked under the optical fiber laser, the laser device selects the optical fiber laser, the laser power selects 30W, the laser speed selects 500mm/s, compared with the area which is not marked, the area marked by the laser has obvious marks, and the marks penetrate through the whole film.

The marking effect is shown in fig. 4.

The obtained PC film is marked under the optical fiber laser, the optical fiber laser is selected by the laser, the laser power is selected to be 25W, 30W, 35W and 40W, the laser speed is selected to be 500mm/s, compared with the area which is not marked, the marked area has obvious marks, and the marks penetrate through the whole film.

The effect of laser marking at different powers is shown in fig. 5.

Example 2

Taking 1kg of polycarbonate particles, 5g of powdery tungsten disulfide, 5g of powdery molybdenum disulfide, 50g of a toughening agent MBS polymer, 1010 g of an antioxidant polyphenol antioxidant and 20g of a lubricant pentaerythritol stearate (PETS); premixing was performed with a high-speed mixer at 4000rpm for 30min.

The obtained PC film is marked under the optical fiber laser, the optical fiber laser is selected by the laser, the laser power is selected, the marked area has obvious marks compared with the unmarked area, and the marks penetrate through the whole film.

The marking effect is shown in fig. 6 to 8.

The effect of laser marking at different powers is shown in fig. 9.

Example 3

Taking 1kg of polycarbonate particles, 8g of powdery tungsten diselenide, 50g of a toughening agent MBS polymer, 1010 g of an antioxidant polyphenol antioxidant and 20g of a lubricant pentaerythritol stearate (PETS); premixing was performed with a high-speed mixer at 4000rpm for 30min.

The obtained PC film is marked under the optical fiber laser, the laser device selects the optical fiber laser, the laser power selects 14W-30W, the laser speed selects 500mm/s, and compared with the area which is not marked, the area marked by the laser has obvious marks and has excellent marking effect.

The marking effect is shown in fig. 10.

Example 4

Taking 1kg of polycarbonate particles, 8g of powdery molybdenum diselenide, 50g of a toughening agent MBS polymer, 1010 g of an antioxidant polyphenol antioxidant and 20g of a lubricant pentaerythritol stearate (PETS); premixing was performed with a high-speed mixer at 4000rpm for 30min.

Example 5

Taking 1kg of polyethylene Particles (PE), 5g of powdery tungsten disulfide, 5g of powdery molybdenum disulfide, 50g of a toughening agent MBS polymer, 1010 g of an antioxidant polyphenol antioxidant and 20g of a lubricant pentaerythritol stearate (PETS); premixing was performed with a high-speed mixer at 4000rpm for 30min.

Adding the mixed PE particles into a double-screw plastic extruder; the temperature of 5 temperature areas of the extruder is respectively set to be 100 ℃,120 ℃,130 ℃,140 ℃ and 145 ℃, the temperature of a machine head is set to be 150 ℃, extrusion is carried out after the temperature of the extruder is stable, the rotating speed of a screw is set to be 250rpm, PE extruded into cylindrical thin strips is pulled to be cooled by a water cooling tank, moisture is sucked by a vacuum pump, and then the PE is pelletized by a pelletizer.

The resulting pellets were dried in a dryer at a temperature set to 70℃for 5 hours to ensure removal of water from the polycarbonate which would otherwise affect the quality of the subsequent film formation. And (3) putting the dried PE particles into a plastic casting machine, wherein the casting machine adopts a four-temperature-zone heating casting machine, the temperature during melting is adjusted to be 100 ℃,120 ℃,130 ℃, 145 ℃ respectively, and the rotating speed of the casting machine is set to be 20rpm. Cutting the edge of the film cast by the casting machine to ensure that the flatness of the obtained film reaches the required requirement, and forming a film by the casting machine, wherein the thickness of the obtained PE film is 100 micrometers, the width is 10cm, and the color is light black.

The obtained PE film is marked under the optical fiber laser, different laser powers are regulated, and compared with the unmarked area, the marked area has obvious marks, and the marks penetrate through the whole film.

Example 6

Taking 1kg of polyethylene Particles (PE), 8g of powdery tungsten diselenide, 50g of a toughening agent MBS polymer, 1010 g of an antioxidant polyphenol antioxidant and 20g of a lubricant pentaerythritol stearate (PETS); premixing was performed with a high-speed mixer at 4000rpm for 30min.

The marking effect is shown in fig. 11.

Example 7

Taking 1kg of polyethylene Particles (PE), 8g of powdered silver sulfide, 50g of a toughening agent MBS polymer, 1010 g of an antioxidant polyphenol antioxidant and 20g of a lubricant pentaerythritol stearate (PETS); premixing was performed with a high-speed mixer at 4000rpm for 30min.

Example 8

Taking 1kg of polypropylene (PP) particles, 5g of powdery tungsten disulfide, 5g of powdery molybdenum disulfide, 50g of a toughening agent MBS polymer, 1010 g of an antioxidant polyphenol antioxidant and 20g of a lubricant pentaerythritol stearate (PETS); premixing was performed with a high-speed mixer at 4000rpm for 30min.

Adding the mixed PP particles into a double-screw plastic extruder; the temperature of 5 temperature areas of the extruder is respectively set to 140 ℃,150 ℃,160 ℃,165 ℃ and 170 ℃, the temperature of a machine head is set to 180 ℃, extrusion is carried out after the temperature of the extruder is stable, the rotating speed of a screw is set to 320rpm, the extruded PP which is in a cylindrical thin strip shape is pulled to be cooled by a water cooling tank, moisture is sucked by a vacuum pump, and then the PP is cut into granules by a granulator.

The resulting pellets were dried in a dryer at 110℃for 5 hours to ensure removal of water from the polycarbonate which would otherwise affect the quality of the subsequent film formation. And (3) putting the dried PP particles into a plastic casting machine, wherein the casting machine adopts a four-temperature-zone heating casting machine, the temperature during melting is adjusted to be 140 ℃,150 ℃,160 ℃ and 165 ℃ respectively, and the rotating speed of the casting machine is set to be 23rpm. Cutting the edge of the film cast by the casting machine to ensure that the flatness of the obtained film reaches the required requirement, and forming a film by the casting machine, wherein the thickness of the obtained PP film is 100 micrometers, the width is 10cm, and the color is light black.

The obtained PP film is marked under the optical fiber laser, different laser powers are regulated, and compared with the area which is not marked, the area marked by the laser has obvious marks, and the marks penetrate through the whole film.

Example 9

Taking 1kg of polypropylene (PP) particles, 8g of powdery molybdenum diselenide, 50g of a toughening agent MBS polymer, 1010 g of an antioxidant polyphenol antioxidant and 20g of a lubricant pentaerythritol stearate (PETS); premixing was performed with a high-speed mixer at 4000rpm for 30min.

The marking effect is shown in fig. 12.

Example 10

Taking 1kg of polypropylene (PP) particles, 8g of powdered silver sulfide, 50g of a toughening agent MBS polymer, 1010 g of an antioxidant polyphenol antioxidant and 20g of a lubricant pentaerythritol stearate (PETS); premixing was performed with a high-speed mixer at 4000rpm for 30min.

Example 11

Taking 1kg of polymethyl methacrylate (PMMA) particles, 5g of powdery tungsten disulfide, 5g of powdery molybdenum disulfide, 50g of a toughening agent MBS polymer, 1010 g of an antioxidant polyphenol antioxidant and 20g of a lubricant pentaerythritol stearate (PETS); premixing was performed with a high-speed mixer at 4000rpm for 30min.

Adding the mixed PP particles into a double-screw plastic extruder; the temperature of 5 temperature areas of the extruder is respectively set to 140 ℃,150 ℃,160 ℃,165 ℃ and 170 ℃, the temperature of a machine head is set to 180 ℃, extrusion is carried out after the temperature of the extruder is stable, the rotating speed of a screw is set to 320rpm, the extruded PMMA in the shape of cylindrical thin strips is pulled to be cooled by a water cooling tank, moisture is sucked by a vacuum pump, and then the PMMA is pelletized by a pelletizer.

The resulting pellets were dried in a dryer at a temperature set to 70℃for 5 hours to ensure removal of water from the polycarbonate which would otherwise affect the quality of the subsequent film formation. And (3) putting the dried PMMA particles into a plastic casting machine, wherein the casting machine adopts a four-temperature-zone heating casting machine, the temperature during melting is adjusted to be 140 ℃,150 ℃,160 ℃ and 165 ℃ respectively, and the rotating speed of the casting machine is set to be 23rpm. Cutting the edge of the film cast by the casting machine to ensure that the flatness of the obtained film reaches the required requirement, and forming a film by the casting machine, wherein the thickness of the obtained PMMA film is 100 micrometers, the width of the PMMA film is 10cm, and the obtained PMMA film is light black.

The obtained PMMA film is marked under the optical fiber laser, different laser powers are regulated, and compared with the area which is not marked, the area marked by the laser has obvious marks, and the marks penetrate through the whole film.

Example 12

Taking 1kg of polymethyl methacrylate (PMMA) particles, 8g of powdery tungsten disulfide, 50g of a toughening agent MBS polymer, 1010 g of an antioxidant polyphenol antioxidant and 20g of a lubricant pentaerythritol stearate (PETS); premixing was performed with a high-speed mixer at 4000rpm for 30min.

Example 13

Taking 1kg of polymethyl methacrylate (PMMA) particles, 8g of powdery molybdenum diselenide, 50g of a toughening agent MBS polymer, 1010 g of an antioxidant polyphenol antioxidant and 20g of a lubricant pentaerythritol stearate (PETS); premixing was performed with a high-speed mixer at 4000rpm for 30min.

Example 14

Taking 1kg of Polystyrene (PS) particles, 5g of powdery tungsten disulfide, 5g of powdery molybdenum disulfide, 50g of a toughening agent MBS polymer, 1010 g of an antioxidant polyphenol antioxidant and 20g of a lubricant pentaerythritol stearate (PETS); premixing was performed with a high-speed mixer at 4000rpm for 30min.

Adding the mixed PS particles into a double-screw plastic extruder; the temperature of 5 temperature areas of the extruder is respectively set to 210 ℃,215 ℃,220 ℃,220 ℃ and 225 ℃, the temperature of a machine head is set to 225 ℃, extrusion is carried out after the temperature of the extruder is stable, the rotating speed of a screw is set to 320rpm, the extruded PS in the shape of cylindrical thin strips is pulled to be cooled by a water cooling tank, moisture is sucked by a vacuum pump, and then the PS is cut into granules by a granulator.

The resulting pellets were dried in a dryer at a temperature set to 70℃for 5 hours to ensure removal of water from the polycarbonate which would otherwise affect the quality of the subsequent film formation. And (3) putting the dried PS particles into a plastic casting machine, wherein the casting machine adopts a four-temperature-zone heating casting machine, the temperature during melting is adjusted to be 140 ℃, 150 ℃, 160 ℃ and 165 ℃ respectively, and the rotating speed of the casting machine is set to be 23rpm. Cutting the edge of the film cast by the casting machine to ensure that the flatness of the obtained film reaches the required requirement, and forming a film by the casting machine, wherein the thickness of the obtained PS film is 100 micrometers, the width is 10cm, and the color is light black.

Example 15

Taking 1kg of Polystyrene (PS) particles, 8g of powdery molybdenum diselenide, 50g of a toughening agent MBS polymer, 1010 g of an antioxidant polyphenol antioxidant and 20g of a lubricant pentaerythritol stearate (PETS); premixing was performed with a high-speed mixer at 4000rpm for 30min.

Comparative example 1

1kg of polycarbonate granules is taken and added into a double-screw plastic extruder; the temperature of 5 temperature areas of the extruder is set to 185 ℃,205 ℃,210 ℃,220 ℃ and 230 ℃, the temperature of a machine head is set to 240 ℃, extrusion is carried out after the temperature of the extruder is stable, the rotating speed of a screw is set to 320rpm, the extruded PC in the shape of cylindrical thin strips is pulled to be cooled by a water cooling tank, moisture is sucked by a vacuum pump, and then the extruded PC is cut into granules by a granulator.

The resulting pellets were dried in a dryer at 110℃for 5 hours to ensure removal of water from the polycarbonate which would otherwise affect the quality of the subsequent film formation. And (3) putting the dried PC particles into a plastic casting machine, wherein the casting machine adopts a four-temperature-zone heating casting machine, the temperature during melting is adjusted to 216 ℃, 252 ℃, 263 ℃ and 252 ℃, and the rotating speed of the casting machine is set to 23rpm. Cutting the edge of the film cast by the casting machine to ensure that the flatness of the obtained film reaches the required requirement, and forming a film by the casting machine to obtain the PC film with the thickness of 100 micrometers and the width of 10cm.

The obtained PC film is marked under the optical fiber laser, different laser powers are regulated, and compared with the area which is not marked, the laser marked area has obvious marks, and the marks penetrate through the whole film.

Comparative example 2

Taking 1kg of polycarbonate particles, 50g of a toughening agent MBS polymer, 1010 g of an antioxidant polyphenol antioxidant, and 20g of a lubricant pentaerythritol stearate (PETS); premixing was performed with a high-speed mixer at 4000rpm for 30min.

Comparative example 3

Taking 1kg of polyethylene Particles (PE), 50g of a toughening agent MBS polymer, 1010 g of an antioxidant polyphenol antioxidant and 20g of a lubricant pentaerythritol stearate (PETS); premixing was performed with a high-speed mixer at 4000rpm for 30min.

Comparative example 4

Taking 1kg of polypropylene (PP) particles, 50g of a toughening agent MBS polymer, 1010 g of an antioxidant polyphenol antioxidant, and 20g of a lubricant pentaerythritol stearate (PETS); premixing was performed with a high-speed mixer at 4000rpm for 30min.

Comparative example 5

Taking 1kg of polymethyl methacrylate (PMMA) particles, 50g of a toughening agent MBS polymer, 1010 g of an antioxidant polyphenol antioxidant and 20g of a lubricant pentaerythritol stearate (PETS); premixing was performed with a high-speed mixer at 4000rpm for 30min.

Comparative example 6

This comparative example used the method for producing a laser-markable polycarbonate film of patent CN 101717566A, 1kg of polycarbonate powder, 5g of tin dioxide, 5g of antimony trioxide, and the heat stabilizer was antioxidant 1010, 20g was taken and pre-mixed with a high-speed mixer, and the mixing speed was set at 1500rpm.

Adding the mixed PC particles into a double-screw plastic extruder; the temperature of 5 temperature areas of the extruder is set to 185 ℃,205 ℃,210 ℃,220 ℃ and 230 ℃, the temperature of a machine head is set to 240 ℃, extrusion is carried out after the temperature of the extruder is stable, the rotating speed of a screw is set to 30rpm, the extruded PC in the shape of cylindrical thin strips is pulled to be cooled by a water cooling tank, moisture is sucked by a vacuum pump, and then the extruded PC is cut into granules by a granulator.

And marking the obtained PC film under the optical fiber laser, adjusting different laser powers, and observing marks.

Table 1 laser marking effect of examples and comparative examples

To characterize the color change of the corresponding polymer film before and after laser marking, the brightness L in the CIE LAB color space is used ^* To represent the change of the gray level of the film, and a color difference meter is used for recording the brightness L of the film ^* The films of example 2 and comparative example 6 were marked with lasers of different powers, L ₀ Representing the brightness of the film before marking, measuring the brightness L of the film before and after marking ₁ The value Δl is the L value variation measured twice, and the formula is as follows:

ΔL = |L ₁ - L ₀ |，

this formula is used to characterize the gray level variation and the contrast of the etched mark.

The films obtained in example 2 and comparative example 6 were marked under a fiber laser, the laser power was set to 14W-38W, the laser rate was set to 500mm/s, and the laser power span between two consecutive marks was 1.2W. Fig. 13 and 14 are graphs showing the marking effect of comparative example 6 and example 2 under a fiber laser, respectively, and it is generally seen that compared with the film made in patent CN 101717566A, the photosensitizer selected in the present invention and the film made by the method of making the same have better marking effect under low power, and the gray scale change is more obvious and the performance is better in the process of increasing the laser power.

The film was marked with three laser powers of 22W, 28W and 40W, and the change in brightness L of the film before and after marking was measured, as shown in table 2.

As can be seen from the data in Table 2, the modified polycarbonate doped with the laser Gao Minji disclosed by the invention has greatly enhanced laser absorption capacity, and the laser polymer material and the product obtained by the method have lower cost and are suitable for large-scale popularization and application.

Table 2 example 2 and comparative example 6 laser marking before and after gray scale contrast

It is apparent that the above examples are given by way of illustration only and are not limiting of the embodiments. Other variations and modifications of the present invention will be apparent to those of ordinary skill in the art in light of the foregoing description. It is not necessary here nor is it exhaustive of all embodiments. And obvious variations or modifications thereof are contemplated as falling within the scope of the present invention.

Claims

1. The preparation method of the laser high-sensitivity film based on the chalcogenide material is characterized by comprising the following steps of:

s11: mixing a high molecular polymer, a toughening agent, a lubricant, an antioxidant and a powdery compound to obtain a mixture; the powdery compound is one or two of sulfide and selenide, and the high molecular polymer is particles or powder;

S12: extruding the mixture, cooling and shearing to obtain plastic particles;

2. The method according to claim 1, wherein the mass ratio of the high molecular polymer to the powdery compound is 1000:5-30.

3. The preparation method of claim 1, wherein the mass ratio of the high molecular polymer, the lubricant, the toughening agent and the antioxidant is 1000:1-20:50-100:20-40.

4. The method of claim 1, wherein the selected high molecular polymer is selected from one or more of polycarbonate, polyethylene, polyvinyl chloride, polystyrene, polytetrafluoroethylene, polypropylene, polyethylene terephthalate, MABS, polymethyl methacrylate, polyamide, polyester, polyphenylene oxide, and polyurethane.

5. The method of preparing according to claim 1, wherein the sulfide is selected from one or more of molybdenum disulfide, tungsten disulfide, titanium disulfide, cobalt disulfide, cuprous sulfide, zinc sulfide, platinum sulfide, vanadium sulfide, silver sulfide, chromium sulfide, cadmium sulfide, nickel sulfide, and indium sulfide; the selenide is selected from one or more of tungsten diselenide, molybdenum diselenide, copper diselenide, zinc diselenide and silver diselenide.

6. The method of manufacture of claim 1, wherein the lubricant is selected from one or more of an ester lubricant, a wax lubricant, a silicone oil, a phenolic resin, and an organophosphate lubricant; the toughening agent is selected from a rubber elastomer toughening agent, a polymer toughening agent or a thermoplastic elastomer toughening agent.

7. The method of claim 1, wherein the antioxidant is selected from the group consisting of phenolic antioxidants, sulfurized phenolic antioxidants, and organosilicon antioxidants.

8. The method according to claim 1, wherein the film thickness in the step S13 is 90 to 110. Mu.m.

9. A chalcogenide material-based laser-sensitive film prepared by the preparation method of any one of claims 1 to 8.

10. Use of a chalcogenide material based laser light sensitive film according to claim 9 in laser marking, comprising the steps of:

s22: and marking the high polymer film under laser to finish the laser marking.