CN112680808A - Frosted transparent flexible melt-blown material and preparation method and application thereof - Google Patents

Frosted transparent flexible melt-blown material and preparation method and application thereof Download PDF

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CN112680808A
CN112680808A CN202011568720.XA CN202011568720A CN112680808A CN 112680808 A CN112680808 A CN 112680808A CN 202011568720 A CN202011568720 A CN 202011568720A CN 112680808 A CN112680808 A CN 112680808A
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styrene
melt
butadiene copolymer
flexible
butadiene
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CN112680808B (en
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魏金刚
杨友强
杨方强
陈振树
周日敏
陶俊浩
李振华
张龙飞
丁超
陈平绪
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Kingfa Science and Technology Co Ltd
Guangdong Kingfa Science and Technology Co Ltd
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Kingfa Science and Technology Co Ltd
Guangdong Kingfa Science and Technology Co Ltd
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Abstract

The invention discloses a frosted transparent flexible melt-blown material and a preparation method and application thereof, wherein styrene-butadiene copolymer is used as a base material, the particle size and the mass content of a butadiene rubber phase are limited, and then the styrene-butadiene copolymer, a functional modified master batch and a hindered amine stabilizer are used together to prepare the melt-blown material; the filter efficiency is high, and the filter material can be widely applied to the preparation of transparent filter materials.

Description

Frosted transparent flexible melt-blown material and preparation method and application thereof
Technical Field
The invention relates to the technical field of melt-blown nonwoven materials, in particular to a frosted transparent flexible melt-blown material and a preparation method and application thereof.
Background
Under the circumstances that the air quality is increasingly poor, along with the increasing of epidemic infectious diseases and the increasing of infectivity, the mask becomes one of necessary tools for people to prevent bacterial and virus infection, harmful dust and the like. In the prior art, the parts below the eyes of the whole face are generally wrapped by polypropylene (PP) non-woven fabrics, so that the bacteria transmission can be effectively avoided, but the conventional disposable medical shell mask/medical N95 mask and the like are basically opaque, so that the main parts of morphological expression are shielded, and the adverse effect is caused on the communication of people. This is because polypropylene, which is the main raw material of non-woven fabrics and melt-blown fabrics, crystallizes during cooling, resulting in an opaque material. Chinese patent CN111499976A (published Japanese 2020.8.7) discloses a polypropylene nucleation and cooling dual-function master batch which is prepared from a foaming carrier, a nucleating agent and peroxide, and when the master batch is used for preparing a melt-blown material, the crystal grains of the melt-blown material can be refined by the nucleating agent and the like, so that a transparent melt-blown material can be obtained, a transparent non-woven fabric can be prepared, but a melt-blown material with flexibility can not be obtained on the basis of transparency.
Disclosure of Invention
The technical problem to be solved by the invention is to overcome the defects and shortcomings that the existing melt-blown material cannot have transparent and flexible texture at the same time, and provide the frosted transparent flexible melt-blown material which is high in transparency, frosted texture, high in flexibility and good in filtering effect.
It is yet another object of the present invention to provide a method of making frosted, transparent, flexible meltblown material.
It is another object of the present invention to provide a frosted transparent flexible meltblown material for use.
The above purpose of the invention is realized by the following technical scheme:
a frosted transparent flexible melt-blown material comprises the following components in parts by mass:
83-97 parts of a styrene-butadiene copolymer;
3-16 parts of functional modified master batch;
0.1-1 part of hindered amine stabilizer;
wherein the particle diameter of a butadiene rubber phase in the styrene-butadiene copolymer is 20-100 nm, and the mass content of butadiene in the styrene-butadiene copolymer is 10-40%.
The invention adopts styrene-butadiene copolymer (SBC) as a base material, and limits the particle size of butadiene rubber phase, the SBC is not crystallized in the melting processing process, and the surface of the melt-blown fabric is not a mirror surface but is rough like fiber, and the frosting effect appears, namely the melt-blown material integrally presents a transparent frosting effect; and because the SBC contains rubber with proper content, the system is ensured not to generate rubber cross-linking, the generation of rough and uneven cloth surface, crystal points and flying is avoided, the flexibility of the material is good, and the material has better filtering performance.
Preferably, the composition comprises the following components in parts by mass:
90-97 parts of styrene-butadiene copolymer resin;
3-8 parts of functional modified master batch;
0.5-1 part of hindered amine stabilizer.
Preferably, the particle size of the butadiene rubber phase in the styrene-butadiene copolymer is 30-80 nm.
Preferably, the mass content of butadiene in the styrene-butadiene copolymer is 20% to 25%.
Preferably, the styrene-butadiene copolymer has a melt index of 30 to 1000g/10min at 230 ℃ and under a test condition of 2.16 kg.
The method for testing the melt index of the styrene-butadiene copolymer comprises the following steps: GB/T3682-2000, the test conditions are 230 ℃ and 2.16 Kg.
Preferably, the preparation method of the styrene-butadiene copolymer comprises the following steps: styrene and butadiene are taken as monomers, alkyl lithium is taken as an initiator, and the preparation is carried out by an anionic solution polymerization method. The preparation method can obtain the styrene-butadiene copolymer with lower rubber phase particle size.
Preferably, the components for preparing the functional modified master batch comprise styrene-butadiene copolymer, electret powder, composite processing lubricant and antioxidant. The melt-blown process is single screw extrusion, and the powder mixing effect is poor; the powder auxiliary agent is firstly prepared into master batch, and during melt-blowing, the extrusion and melting have good dispersion effect, the transparent frosted texture and the flexibility of the material are not influenced, and the material is endowed with better filtering performance.
More preferably, the functional modified master batch prepared comprises the following components in parts by mass: 60-95 parts of styrene-butadiene copolymer, 3-30 parts of electret powder, 0.2-2 parts of composite processing lubricant and 0.1-2 parts of antioxidant.
The electret powder comprises one or more of but not limited to nano tourmaline powder, nano silicon dioxide, polyvinylidene fluoride and polytetrafluoroethylene.
The composite processing lubricant provided by the invention comprises, but is not limited to, 1: 1 (PPA) and diatomaceous earth.
The antioxidant of the invention includes but is not limited to one or more of hindered phenol antioxidants, phosphite antioxidants, amine antioxidants, sulfur antioxidants or metal salt antioxidants.
The antioxidant provided by the invention comprises, but is not limited to, 1: 2 antioxidant 1010 and antioxidant 168.
Preferably, a dispersant and/or a toner is further included.
Preferably, the preparation method of the functional modified master batch comprises the following steps: the styrene-butadiene copolymer, the electret powder, the composite processing lubricant and the antioxidant are blended and extruded by a double screw to obtain the composite material.
The hindered amine stabilizer provided by the invention comprises but is not limited to one or more of 2,2,6, 6-tetramethyl piperidine and substituted derivatives thereof, imidazolidinone and derivatives thereof, and azacyclo-alkanone and derivatives thereof.
The hindered amine stabilizers of the present invention include, but are not limited to, bis (2,2,6, 6-tetramethyl-4-piperidyl) sebacate (HS-770), poly { [6- [ (1,1,3, 3-tetramethylbutyl) amino ] ] -1,3, 5-triazine-2, 4- [ (2,2,6,6, -tetramethyl-piperidyl) imine (HS-944), HS-200N, n' -bis (2,2,6, 6-tetramethyl-4-piperidyl) -1, 6-hexanediamine and one or more of 2,4, 6-trichloro-1, 3, 5-triazine, N-butyl-1-butylamine and N-butyl-2, 2,6, 6-tetramethyl-4-piperidylamine (HS-2020).
The invention protects the preparation method of the flexible melt-blown material, which comprises the following steps:
uniformly mixing the styrene-butadiene copolymer, the functional modified master batch and the hindered amine stabilizer, performing melt extrusion, performing electret treatment, and drying to obtain the flexible melt-blown material.
Preferably, the extrusion amount during melt extrusion is 35Hz, the hot air pressure is 0.08MPa, the hot air temperature is 240 ℃, the receiving distance is 25cm, and the transmission speed of the screen is 7.5 Hz.
Preferably, the temperature of each zone in the melt extrusion is set to 220 ℃, 230 ℃, 235 ℃, 240 ℃ and 240 ℃.
Preferably, the drying temperature is 70-100 ℃.
The invention also protects the application of the flexible melt-blown material in preparing a transparent filter material.
A transparent mask comprises the flexible melt-blown material.
Compared with the prior art, the invention has the beneficial effects that:
the styrene-butadiene copolymer is used as a base material, the particle size and the mass content of a butadiene rubber phase of the styrene-butadiene copolymer are limited, and then the styrene-butadiene copolymer, the functional modified master batch and the hindered amine stabilizer are used together to prepare the melt-blown material; the filter efficiency is high, and the filter material can be widely applied to the preparation of transparent filter materials.
Detailed Description
The present invention will be further described with reference to specific embodiments, but the present invention is not limited to the examples in any way. The starting reagents employed in the examples of the present invention are, unless otherwise specified, those that are conventionally purchased.
The raw materials used in the respective examples and comparative examples:
SBC-A: a838, melt flow rate of 50g/10min (230 ℃/2.16kg), wherein the particle size of the butadiene rubber phase is 60nm, and the weight content of butadiene is about 40%; (iii) Japanese Asahi chemical;
SBC-B: SL-825, melt index 40g/10min (230 ℃/2.16kg), rubber average particle size 60nm, butadiene content 25% by weight; the well-known and well-known company;
SBC-C: the particle diameter of the butadiene rubber phase is 60nm, and the weight content of butadiene is about 10 percent; melt flow rate of 50g/10min (230 ℃/2.16kg), Town-Jones;
SBC-D: the particle size of the butadiene rubber phase is 100nm, and the weight content of butadiene is 25 percent; melt flow rate of 50g/10min (230 ℃/2.16kg), Town-Jones;
SBC-E: the particle size of the butadiene rubber phase is 20nm, and the weight content of butadiene is 25 percent; melt flow rate of 50g/10min (230 ℃/2.16kg), Town-Jones;
SBC-F: GPRENE 3414; the particle size of the butadiene rubber phase is 180nm, and the weight content of butadiene is 60 percent; a plastic group; the melt flow rate was 40g/10min (230 ℃/2.16 kg);
SBC-G: the mass content of butadiene in the styrene-butadiene copolymer was 5%, and the melt flow rate was 50g/10min (230 ℃/2.16 kg); the particle size of the butadiene rubber phase is 60nm, and the product is obtained by the famous and publicly known company;
SBC-H: the mass content of butadiene in the styrene-butadiene copolymer was 50%, and the melt flow rate was 50g/10min (230 ℃/2.16 kg); the particle size of the butadiene rubber phase is 10nm, and the product is obtained by the famous and publicly known company;
nano tourmaline powder: MC-80, Shijiazhuang Ming Chi color Sand group Co., Ltd;
PPA: FX-5924, 3M;
diatomite: infilm 300, IMERYS yiruite corporation;
hindered amine light stabilizer: chimassorb 944DF, basff;
PP: PP-91500, Jinfa science and technology;
functional modified master batch: 85 parts of SBC, 10 parts of nano tourmaline powder serving as electret powder, 0.1 part of PPA, 0.1 part of diatomite and 0.2 part of antioxidant are subjected to melt extrusion granulation by a double-screw extruder to prepare the functional modified master batch.
Example 1
A frosted transparent flexible meltblown material comprising the components in parts by mass as shown in Table 1 below.
The preparation method of the frosted transparent flexible melt-blown material comprises the following steps:
uniformly mixing SBC, the functional modified master batch and the hindered amine light stabilizer, feeding the mixture into a storage bin of a screw extruder, and performing melt extrusion by the screw extruder to form a melt, wherein the temperatures of six heating regions of the screw extruder are respectively set to be 220 ℃, 230 ℃, 235 ℃, 240 ℃ and 240 ℃; keeping the temperature of the melt at 225 ℃ in a pipeline at constant temperature, metering the melt by a metering pump, spraying the melt out by a spinneret plate to form fibers, and drafting the fibers by hot air at constant temperature and constant pressure of 240 ℃ and 0.07MPa to form melt-blown cloth on a net curtain; and sequentially carrying out water electret treatment on the obtained melt-blown fabric, carrying out infrared drying treatment at the temperature of 70 ℃, and rolling to obtain the flame-retardant polyester fabric.
Examples 2 to 10 and comparative examples 1 to 4
The melt-blown material components of examples 2 to 10 and comparative examples 1 to 4 are shown in tables 1 and 2 below, and the preparation method is the same as that of example 1.
TABLE 1 Components and parts by mass of the examples
Figure BDA0002861819660000051
TABLE 2 Components and parts by mass of the examples
Figure BDA0002861819660000052
Figure BDA0002861819660000061
Performance testing
1. Test method
(1) The gram weight of the melt-blown non-woven fabric is controlled according to the FZ/T60003-;
(2) transverse rupture strength and transverse rupture elongation test standard FZ/T60005-1991;
(3) the filtration efficiency test standard GB 2626-2019; the medium adopts NaCl particles with the number median diameter of 0.075 +/-0.02 mu m, and the test flow is 85L/min;
(4) softness test Standard GB/T8942-2016; the larger the value, the better the softness, and above 25, the softness can meet the requirements of practical application.
(5) And (3) transparency test: the whiteness tester for testing uses a tungsten lamp as an illumination light source, the tungsten lamp is modified into a simulated CIE standard D65 light source through a filter, the main peak wavelength of the spectral power distribution of an ISO whiteness optical system is 457nm, and the obtained higher the light transmittance data is, the more transparent the test is.
2. Test results
TABLE 3 test results of examples and comparative examples
Figure BDA0002861819660000062
According to the light transmittance of the material, the material can be divided into the following three types: the light transmittance of the transparent material is more than 80% when visible light with the wavelength of 400-800 nm is used; the light transmittance of visible light with the wavelength of 400-800 nm is 50-80 percent; the light transmittance of the opaque material for visible light with the wavelength of 400-800 nm is below 50%. The light transmittance is high, and if the surface of an object is not a mirror surface, the object can have a frosted glass-like feeling, and the surface of the melt-blown fabric is not a mirror surface, but has a rough feeling similar to fibers, so that the frosted effect can be achieved.
As can be seen from Table 3, the melt-blown material prepared by the embodiments of the present invention has high light transmittance, frosted effect, flexible property and good filtering effect. Under the condition that the gram weights are basically consistent, compared with the conventional polypropylene melt-blown fabric in a comparative example 1, the transparency of the embodiment of the invention is improved by about 3 times, the light transmittance is obviously increased, the embodiment belongs to a semitransparent material, and the integral frosty glass-like feeling is presented by combining the uneven surface formed by the melt-blown fabric fibers; meanwhile, the filtering effect of the particles after electret treatment reaches KN95 level, and compared with the polypropylene melt-blown material in comparative example 1, the polypropylene melt-blown material has the advantages of higher breaking elongation, increased softness and certain improvement on flexibility under the condition of equivalent gram weight. In comparative example 2, the content of the styrene-butadiene copolymer resin rubber is high, the extrusion is easy to generate a flow unstable state, the filtration efficiency of the prepared melt-blown fabric particles is less than 85%, and meanwhile, the rubber has large particle size and poor transparent effect. The SBC adopted in the comparative example 3 has low butadiene content, the rubber in the comparative example 4 has too small particle size, the rubber cannot achieve effective toughening, the elongation at break and the softness of the two systems are low, the two systems do not have the characteristic of flexibility, and the light transmittance is also influenced to a certain degree. The results show that the melt-blown material has frosted and transparent appearance, good flexibility and high filtering efficiency, provides a greater choice for developing personalized products and improving aesthetic design degree, and can be widely applied to preparing transparent filtering materials.
It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.

Claims (10)

1. A frosted transparent flexible melt-blown material is characterized by comprising the following components in parts by mass:
83-97 parts of a styrene-butadiene copolymer;
3-16 parts of functional modified master batch;
0.1-1 part of hindered amine stabilizer;
wherein the particle diameter of a butadiene rubber phase in the styrene-butadiene copolymer is 20-100 nm, and the mass content of butadiene in the styrene-butadiene copolymer is 10-40%.
2. The flexible meltblown material according to claim 1, comprising the following components in parts by mass:
90-97 parts of a styrene-butadiene copolymer;
3-8 parts of functional modified master batch;
0.5-1 part of hindered amine stabilizer.
3. The flexible meltblown material according to claim 1 or 2 wherein the butadiene rubber phase of the styrene-butadiene copolymer has a particle size of 30 to 80 nm.
4. The flexible meltblown material according to claim 1 wherein the mass content of butadiene in the styrene-butadiene copolymer is between 20% and 25%.
5. The flexible meltblown material according to claim 1 wherein the styrene-butadiene copolymer has a melt index of 30 to 1000g/10min at 230 ℃ under a test condition of 2.16 kg.
6. The flexible meltblown material according to claim 1, wherein the functional modifying masterbatch is prepared from ingredients comprising styrene-butadiene copolymer, electret powder, composite processing lubricant, and antioxidant.
7. The flexible meltblown material according to claim 1 wherein the hindered amine stabilizer is one or more of 2,2,6, 6-tetramethylpiperidine and substituted derivatives thereof, imidazolidinone and derivatives thereof, and azacyclic alkanones and derivatives thereof.
8. A method of producing a flexible meltblown material according to any of claims 1 to 7, comprising the steps of:
uniformly mixing the styrene-butadiene copolymer, the functional modified master batch and the hindered amine stabilizer, performing melt extrusion, performing electret treatment, and drying to obtain the flexible melt-blown material.
9. Use of a flexible meltblown material according to any of claims 1 to 7 for the production of a transparent filter material.
10. A see-through mask comprising the flexible melt-blown material according to any one of claims 1 to 7.
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US7067188B1 (en) * 1999-01-21 2006-06-27 Arkema Polymeric articles having a textured surface and frosted appearance
JP2006233437A (en) * 2005-02-22 2006-09-07 Kii Techno Kk Transparent protecting tube for outer cable
CN101925649A (en) * 2008-02-15 2010-12-22 埃克森美孚化学专利公司 Blends of low crystallinity, low molecular weight propylene copolymers and styrenic block copolymers
CN104892859A (en) * 2015-05-27 2015-09-09 长春工业大学 Transparent rubber modified styrene resin and preparation method thereof
CN111423691A (en) * 2020-03-20 2020-07-17 南通普力马弹性体技术有限公司 Low hardness, transparent elastomeric materials and methods of making the same
CN111499976A (en) * 2020-05-22 2020-08-07 星贝达(上海)化工材料有限公司 Polypropylene nucleating and cooling difunctional master batch and preparation method and application thereof
CN111607895A (en) * 2020-06-23 2020-09-01 常州工程职业技术学院 Melt-blown fabric suitable for filtering oily particles and preparation method thereof

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7067188B1 (en) * 1999-01-21 2006-06-27 Arkema Polymeric articles having a textured surface and frosted appearance
JP2006143758A (en) * 2004-11-16 2006-06-08 Tosoh Corp Transparent resin composition and transparent film
JP2006233437A (en) * 2005-02-22 2006-09-07 Kii Techno Kk Transparent protecting tube for outer cable
CN101925649A (en) * 2008-02-15 2010-12-22 埃克森美孚化学专利公司 Blends of low crystallinity, low molecular weight propylene copolymers and styrenic block copolymers
CN104892859A (en) * 2015-05-27 2015-09-09 长春工业大学 Transparent rubber modified styrene resin and preparation method thereof
CN111423691A (en) * 2020-03-20 2020-07-17 南通普力马弹性体技术有限公司 Low hardness, transparent elastomeric materials and methods of making the same
CN111499976A (en) * 2020-05-22 2020-08-07 星贝达(上海)化工材料有限公司 Polypropylene nucleating and cooling difunctional master batch and preparation method and application thereof
CN111607895A (en) * 2020-06-23 2020-09-01 常州工程职业技术学院 Melt-blown fabric suitable for filtering oily particles and preparation method thereof

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