A composition capable of laser marking with light diffusion effect, preparation method and application thereof

Abstract

The present invention relates to a composition capable of laser marking to produce a light diffusion effect, and a preparation method and application thereof. The composition capable of laser marking to produce a light diffusion effect comprises a composite material and a black-on-white laser marking agent. The present invention uses a specific content of polymethyl methacrylate and acrylonitrile-styrene copolymer as a base material, and then adds a trace amount of black-on-white laser marking agent to obtain a composition, and the composition can be laser-marked to produce a specific pattern with a light diffusion effect, thereby achieving a diffusion effect.

Description

Technical Field

[0001] The present invention belongs to the technical field of light diffusion, and in particular relates to a composition capable of laser marking to produce a light diffusion effect, and a preparation method and application thereof. Background Art

[0002] The important application fields of light diffusion materials are mainly the preparation of light diffusion plates for displays and lampshades for lighting. The function of light diffusion is to refract, reflect and scatter light, converting point light sources into surface light sources, so as to reduce the intensity of direct light, increase the intensity of scattered light, and achieve uniform diffusion of light. At present, the mainstream way to achieve the light diffusion effect is to add light diffusers, and a few patents have reported that it can be achieved by constructing surface microstructures. However, the light diffusion products prepared by these methods are generally formed as a whole at one time through extrusion or injection molding. The product as a whole shows a light diffusion effect, and the light diffusion effect cannot be achieved at a specific position. The preparation of light diffusion patterns can only be combined into a specific light diffusion pattern through subsequent cutting, assembly and gluing processes, which is complicated and costly.

[0003] Developing a material that can locally exhibit light diffusion effects has important research significance and economic value. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects or shortcomings of the prior art in that the process for preparing a specific light diffusion pattern is complicated and the cost is high, and to provide a composition that can be laser-marked to produce a light diffusion effect, and a preparation method and application thereof. The present invention uses a specific content of polymethyl methacrylate and acrylonitrile-styrene copolymer as a base material, and then adds a trace amount of black-on-white laser marking agent to obtain a composition. The composition can be laser-marked to produce a specific pattern with a light diffusion effect, thereby achieving a diffusion effect.

[0005] Another object of the present invention is to provide a method for preparing the above-mentioned composition capable of laser marking with light diffusion effect.

[0006] Another object of the present invention is to provide the use of the above-mentioned composition capable of laser marking with light diffusion effect in the preparation of products with light diffusion effect.

[0007] In order to achieve the above-mentioned invention object, the present invention adopts the following technical scheme:

[0008] A composition capable of laser marking with light diffusion effect, comprising the following components in parts by weight:

[0009] 100 parts of compound,

[0010] 0.01~0.05 parts of black on white laser marking agent,

[0011] The composite is composed of polymethyl methacrylate and acrylonitrile-styrene copolymer, and the weight ratio of the polymethyl methacrylate to the acrylonitrile-styrene copolymer is 10:(1-4).

[0012] The present invention uses a specific amount of polymethyl methacrylate and acrylonitrile-styrene copolymer as a base material, and then adds a trace amount of black-on-white laser marking agent to the base material to obtain a composition. When the composition is laser marked, the laser marking agent absorbs laser energy and generates heat and decomposes, forming many tiny bubbles in the composition. By matching the refractive index of the composite and the small bubbles, the light is fully refracted, reflected and scattered in the composition, thereby generating a bright light diffusion effect at the laser marking location.

[0013] According to the need for the size of the light diffusion area, the range of laser marking can be adjusted to obtain the desired local light diffusion effect. It should be understood that if the overall light diffusion effect is required, the entire surface can be laser marked.

[0014] The composition of the composite has a great influence on its refractive index, which in turn affects the light diffusion effect. If the refractive index of the composite is too high, its light transmittance will decrease after laser marking, and the product will be dark; if the refractive index of the composite is too low, its haze will decrease after laser marking, and the light diffusion effect will not be achieved. The higher the content of acrylonitrile-styrene copolymer, the higher the refractive index. The refractive index of the composite can be adjusted by adjusting the ratio of polymethyl methacrylate and acrylonitrile-styrene copolymer.

[0015] Preferably, the refractive index of the composite is 1.51-1.54.

[0016] Preferably, the polymethyl methacrylate has a melt index of 0.5-3 ml / 10 min at 230° C. and 3.8 kg according to ISO1133-2011.

[0017] Preferably, the refractive index of the acrylonitrile-styrene copolymer is 1.56-1.58.

[0018] The refractive index of the composite and acrylonitrile-styrene copolymer is measured in accordance with the inspection standard GB / T 39691-2020.

[0019] Preferably, the preparation method of the composite is as follows: polymethyl methacrylate and acrylonitrile-styrene copolymer are uniformly mixed, then melted, extruded, and granulated to obtain the composite.

[0020] More preferably, the preparation method of the composite is as follows: dry mixing polymethyl methacrylate and acrylonitrile-styrene copolymer in a mixer for 3 to 5 minutes at a rotation speed of 60 to 100 rpm; then adding them to a twin-screw extruder for melting, extrusion, and granulation to obtain the composite, wherein the aspect ratio of the twin-screw extruder is 40:1 to 65:1, the barrel temperature is 160 to 220°C, and the rotation speed is 300 to 450 rpm.

[0021] Preferably, the black-on-white laser marking agent is carbon black.

[0022] Preferably, the composition capable of laser marking with light diffusion effect further comprises other processing aids, and the weight proportion of the other processing aids is 0 to 0.5 parts, more preferably 0.1 to 0.3 parts.

[0023] More preferably, the other processing aids are one or more of antioxidants, lubricants or weathering agents.

[0024] Further preferably, the antioxidant is one or more of antioxidant 1010, antioxidant 1098, antioxidant 1076, antioxidant 168 or antioxidant PEP-36.

[0025] More preferably, the lubricant is one or more of ethylene bisstearamide, calcium stearate or magnesium stearate.

[0026] Further preferably, the weathering agent is one or more of the ultraviolet absorber UV-P, light stabilizer 770 or light stabilizer 944.

[0027] The method for preparing the above-mentioned composition capable of laser marking with light diffusion effect comprises the following steps:

[0028] The composite material and the laser marking agent are uniformly mixed to obtain a mixture, and then the mixture is melted, extruded, and granulated to obtain the composition capable of laser marking with light diffusion effect.

[0029] Preferably, the method for preparing the composition capable of laser marking with light diffusion effect comprises the following steps: uniformly mixing the composite, the laser marking agent and the laser absorber in a high-speed mixer to obtain a mixture, and then adding the mixture into a twin-screw extruder for melt extrusion and granulation to obtain the composition capable of laser marking with light diffusion effect.

[0030] More preferably, a high-speed mixer is used for stirring and mixing, and the stirring speed is 60-100 rpm and the time is 3-5 min.

[0031] More preferably, a twin-screw extruder is used for melt extrusion and granulation; the extrusion temperature of the twin-screw extruder is 160-220° C., the aspect ratio is 40-65:1, and the screw speed is 300-450 rpm.

[0032] The use of the above-mentioned composition capable of laser marking with light diffusion effect in the preparation of products with light diffusion effect is also within the protection scope of the present invention.

[0033] The composition that can be laser-marked to produce a light diffusion effect can be prepared into various shapes, such as a smooth surface, a convex surface, a concave surface, a plane, an inclined surface, a curved surface or an irregular shape, by extrusion or injection molding as needed; and then various patterns, numbers or planes with a diffusion effect are formed on the various shapes by laser marking, thereby obtaining a product with a light diffusion effect.

[0034] Preferably, the product is a light diffuser plate or a lampshade.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] The present invention uses polymethyl methacrylate and acrylonitrile-styrene copolymer with specific contents as a base material, and then adds a trace amount of black-on-white laser marking agent to obtain a composition, which can be laser-marked to produce a specific pattern with light diffusion effect, thereby achieving a diffusion effect. DETAILED DESCRIPTION

[0037] The present invention is further described below in conjunction with examples. These examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention. The experimental methods in the following examples that do not specify specific conditions are usually carried out according to conventional conditions in the art or according to the conditions recommended by the manufacturer; the raw materials, reagents, etc. used, unless otherwise specified, are all raw materials and reagents that can be obtained from commercial channels such as conventional markets. Any non-substantial changes and substitutions made by those skilled in the art on the basis of the present invention belong to the scope of protection claimed by the present invention.

[0038] Some of the reagents selected in the embodiments and comparative examples of the present invention are described as follows:

[0039] A. Components of the complex:

[0040] PMMA1# (polymethyl methacrylate): CM-205, Chimei, according to ISO1133-2011, the melt index at 230°C and 3.8kg is 1.9ml / 10min;

[0041] PMMA2# (polymethyl methacrylate): CM-207, Chimei, according to ISO1133-2011, the melt index at 230°C and 3.8kg is 8.5ml / 10min;

[0042] SAN 1# (acrylonitrile-styrene copolymer): 350N, Kumho, South Korea, refractive index 1.58;

[0043] SAN 2# (acrylonitrile-styrene copolymer): 310NTR, Kumho, South Korea, refractive index 1.56;

[0044] Composite 1#: PMMA 1# and SAN 1# are compounded at a ratio of 10:1 (weight ratio, the same below), with a refractive index of 1.51;

[0045] Composite 2#: obtained by compounding PMMA 1# and SAN 1# at a ratio of 10:2; refractive index is 1.52;

[0046] Composite 3#: obtained by compounding PMMA 1# and SAN 1# at a ratio of 10:4; refractive index is 1.53;

[0047] Composite 4#: obtained by compounding PMMA 2# and SAN 2# at a ratio of 10:2; refractive index is 1.51;

[0048] Composite 5#: obtained by compounding PMMA 1# and SAN 1# at a ratio of 10:0.5; refractive index is 1.50;

[0049] Composite 6#: obtained by compounding PMMA 1# and SAN 1# at a ratio of 10:6; the refractive index is 1.55.

[0050] Composites 1#~6# are prepared by the following process: each component is placed in a mixer with a rotation speed of about 100 rpm and dry mixed for 3-5 minutes, and then the mixed raw materials are melt-extruded and granulated in a twin-screw extruder with a length-to-diameter ratio of 40:1, a temperature range of 160°C, 190°C, 190°C, 200°C, 210°C, 210°C, 220°C, 220°C, 220°C, and a rotation speed of 450 rpm to obtain transparent plastic particles, which are the composites.

[0051] The refractive index of the composite is measured according to the inspection standard GB / T 39691-2020.

[0052] B. Laser marking agent

[0053] Carbon black 1, DENKA BLACK, Nippon Denka Chemical Industry Co., Ltd.;

[0054] Carbon black 2, 1013F, Anhui Heiyu Pigment New Materials Co., Ltd.

[0055] C. Other processing aids:

[0056] Antioxidant 1010, BASF, Germany.

[0057] The composition (or composition) capable of laser marking with light diffusion effect in the embodiments of the present invention and the comparative examples is prepared by the following process:

[0058] Weigh each component and put it into a mixer with a rotation speed of about 100 rpm for dry mixing for 4 minutes, then melt-extrude and granulate the mixed raw materials in a twin-screw extruder with a length-to-diameter ratio of 40:1, a temperature range of 160°C, 190°C, 190°C, 200°C, 210°C, 210°C, 220°C, 220°C, 220°C, and a rotation speed of 450 rpm to obtain plastic particles, which is a composition (or compositions) that can be laser marked with light diffusion effect.

[0059] The plastic particles were injection molded at about 200° C. into color plates (thickness 2 mm).

[0060] The color plates obtained by injection molding the composition (or composition) capable of laser marking to produce light diffusion effect in each embodiment and comparative example were laser marked by a Han's Laser EP-12 laser marking machine at a current of 20A, a marking speed of 1000mm / s, and a frequency of 17KHz to obtain light diffusion patterns. The color, light transmittance, haze, and light diffusion effect of the laser marked area in the color plate after laser marking were tested.

[0061] (1) Color: Observe the color with the naked eye under visible light and measure the L value using a colorimeter in accordance with GB / T 11186-1989.

[0062] (2) Light transmittance: Measured in accordance with GB / T 2410-2008, thickness 2 mm.

[0063] (3) Haze: Measured in accordance with GB / T 2410-2008, thickness 2 mm.

[0064] (4) Light diffusion effect: When the transmittance is ≥30% and the haze is ≥70%, it has a bright light diffusion effect; when the transmittance is less than 30% and the haze is ≥70%, it has a darker light diffusion effect; when the transmittance is ≥30% and the haze is less than 70%, the light diffusion effect is poor; when the transmittance is less than 30% and the haze is less than 70%, there is no light diffusion effect.

[0065] Embodiments 1 to 8

[0066] This embodiment provides a series of compositions that can be laser marked to produce light diffusion effect, and the formulas thereof are shown in Table 1.

[0067] Table 1 Formulas of Examples 1 to 8 (parts)

[0068]

[0069] Comparative Examples 1 to 4

[0070] This comparative example provides a series of compositions, and the formulas thereof are shown in Table 2.

[0071] Table 2 Formulas of Comparative Examples 1 to 4 (parts)

[0072]

[0073] The performance of the composition (or compositions) capable of laser marking with light diffusion effect provided by each embodiment and comparative example was tested according to the aforementioned performance testing method. The results are shown in Table 3.

[0074] Table 3 Performance test results of the composites provided by Examples 1 to 8 and Comparative Examples 1 to 4

[0075]

[0076] It can be seen from the above test results that after laser marking, the composition provided by the present invention that can be laser-marked with a light diffusion effect has a high haze and transmittance in the light diffusion pattern area, and a bright light diffusion effect can be achieved, among which the performance of Example 2 is the best. The ratio of polymethyl methacrylate and acrylonitrile-styrene copolymer in the composite selected in Comparative Example 1 is too large, resulting in a small refractive index of the composite. After laser marking, the transmittance is large, the haze decreases, and the light diffusion effect is poor. The ratio of polymethyl methacrylate and acrylonitrile-styrene copolymer in the composite selected in Comparative Example 2 is too small, resulting in a large refractive index of the composite. Although better light diffusion can be achieved after laser marking, the transmittance is low, the light loss is large, and the light diffusion effect is not bright enough. Comparative Example 3 does not add a laser marking agent, and laser marking cannot be performed. Too much laser marking agent is added in Comparative Example 4, and it will carbonize and blacken after laser engraving, and there is no light diffusion effect.

[0077] Those skilled in the art will appreciate that the embodiments herein are intended to help readers understand the principles of the present invention, and should be understood that the protection scope of the present invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific variations and combinations that do not deviate from the essence of the present invention based on the technical revelations disclosed by the present invention, and these variations and combinations are still within the protection scope of the present invention.

Claims

1. Use of a composition capable of laser marking to produce a light diffusion effect in the preparation of a product having a light diffusion effect, characterized in that: The light diffusion effect of the product is achieved by laser marking a pattern of light diffusion effect on the composition; the light transmittance of the laser marked area of ​​the product is ≥30%, and the haze is ≥70%; The composition capable of laser marking with light diffusion effect comprises the following components in parts by weight: 100 parts of compound, 0.01~0.05 parts of black on white laser marking agent, The composite is composed of polymethyl methacrylate and acrylonitrile-styrene copolymer, and the weight ratio of the polymethyl methacrylate to the acrylonitrile-styrene copolymer is 10:(1-4); The black-on-white laser marking agent is carbon black.

2. The application according to claim 1, characterized in that: The refractive index of the composite is 1.51-1.

54.

3. The application according to claim 1, characterized in that: According to ISO1133-2011, the melt index of the polymethyl methacrylate is 0.5-3 ml / 10 min at 230° C. and 3.8 kg.

4. The use according to claim 1, characterized in that: The refractive index of the acrylonitrile-styrene copolymer is 1.56-1.

58.

5. The use according to claim 1, characterized in that: The composition capable of laser marking to produce a local light diffusion effect further comprises other processing aids, and the weight proportion of the other processing aids is 0 to 0.5 parts.

6. The use according to claim 5, characterized in that: The other processing aids are one or more of antioxidants, lubricants or weathering agents.

7. The use according to claim 1, characterized in that: The light transmittance of the laser-marked area of ​​the product is 30-34%, and the haze is 72-83%.

8. The use according to claim 1, characterized in that: The preparation method of the composition capable of laser marking with local light diffusion effect comprises the following steps: uniformly mixing the compound and the laser marking agent to obtain a mixture, and then melt-extruding and granulating the mixture to obtain the composition capable of laser marking with light diffusion effect.

9. The use according to claim 1, characterized in that: The product is a light diffuser plate or a lampshade.

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