JP2014124853A - Laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminate that has a high surface hardness, an antibacterial property and an excellent hue, and that is composed of inexpensive resin.SOLUTION: A laminate is provided that is formed by laminating a surface layer material composed of polycarbonate resin composition (B) to at least one surface of a base material composed of transparent synthetic resin (A), the resin composition (B) containing a particular surface hardness enhancing agent and an antibacterial agent. The laminate of the invention has a high surface hardness, an antibacterial property and an excellent hue. Thus such a laminate is suitably used in applications in which molding surface damage should be avoided, transparency is required, and features for comfortableness, cleanliness and safety are desired, such as displays, electric home appliances and stationery goods. The use of inexpensive surface hardness enhancing agent and antibacterial agent provides efficient improvement of surface hardness and antibacterial property as well as cost effectiveness.

Description

  The present invention relates to a laminate obtained by laminating a surface layer material made of a polycarbonate resin composition excellent in surface hardness, antibacterial properties and hue on at least one surface of a base material made of a transparent synthetic resin.

  Polycarbonate resin is a thermoplastic resin excellent in impact resistance, heat resistance, transparency, thermal stability, and the like, and is therefore used as a substitute for glass in windows and display parts of automobiles and building materials. However, the polycarbonate resin has a drawback that it has a low surface hardness and is easily damaged, and its use is limited. In addition, household appliances such as refrigerators and vacuum cleaners and miscellaneous goods such as hanging rings are required to have performance that leads to comfort, cleanliness and safety. In order to satisfy these various performances, generally, a technique of blending an organic or inorganic antibacterial agent with a polycarbonate resin is employed.

  In order to improve the susceptibility to scratches, there has been proposed a method of hard coating an ultraviolet curable coating on a laminate comprising an acrylic resin layer and a polycarbonate resin layer. (Patent Document 1) has a problem in that the refractive index of the acrylic resin and the polycarbonate resin is different, so that the transparency is lowered when the ears of the laminate and the used laminate are pulverized, melted, kneaded, and molded for the purpose of recycling. was there.

In order to obtain a molded article excellent in surface hardness and transparency, a resin composition of a polycarbonate resin and an acrylic surface hardness improver has been proposed. (Patent Documents 2 and 3) However, this resin composition has a problem that the surface hardness is high but the hue is inferior. Moreover, the resin composition of the polycarbonate resin and the acrylic surface hardness improver disclosed in Patent Document 2 and Patent Document 3 is not disclosed for use as a surface material of a laminate.
Moreover, since the acrylic surface hardness improver is generally expensive, a molded article made of a resin excellent in cost has been desired.

JP 2006-103169 A JP 2009-280713 A JP 2010-116501 A

  On the other hand, since an antibacterial property is imparted to the polycarbonate resin, an inorganic antibacterial agent has been conventionally used because of its excellent safety and thermal stability. For example, an antibacterial agent comprising a zeolite (Patent Document 4) carrying a metal ion such as silver or zinc having a strong antibacterial action against bacteria, or a soluble glass (Patent Documents 5 and 6) containing the metal ion. Can be mentioned.

  In addition, a synthetic resin molded body having antibacterial properties including a water-soluble glass that releases silver ions and a highly water-absorbent resin body are disclosed in a non-moisture permeable synthetic resin and a highly water-absorbent resin (Patent Documents). 7 and 8).

  However, the molding process temperature may vary depending on the shape of the molded product and the resin used, but it may be as high as 400 ° C. In such a case, the soluble glass reacts with the transparent resin, resulting in transparency and heat stability. There was a problem of causing a decline in sex.

Japanese Patent No. 3293639 Japanese Patent No. 2135769 Japanese Patent Laid-Open No. 7-25635 Japanese Patent Laid-Open No. 1-313531 Japanese Patent Laid-Open No. 1-153748

  An object of the present invention is to provide an inexpensive resin laminate having the above-mentioned problems, that is, high surface hardness, antibacterial properties and excellent hue.

  As a result of intensive studies to solve the above-mentioned problems, the inventors of the present invention have sufficient performance because surface hardness and antibacterial properties are sufficient to be expressed on the surface of the molded body or its periphery. It is found that by laminating a polycarbonate resin composition to be laminated on a transparent synthetic resin base material as a surface layer material, it is possible to obtain a laminate having excellent cost and transparency, surface hardness and antibacterial properties. The invention has been completed.

That is, the present invention provides a laminate in which a surface layer material made of a polycarbonate resin composition (B) is laminated on at least one surface of a base material made of a transparent synthetic resin (A).
The glass in which the polycarbonate resin composition (B) elutes silver ions per 100 parts by weight of the resin component consisting of 35 to 75% by weight of the polycarbonate resin (B1) and 25 to 65% by weight of the surface hardness improver (B2). An antibacterial agent (B3) as an essential component is a resin composition containing 0.05 to 1.5 parts by weight,
The surface hardness improver (B2) is a copolymer composed of 5 to 80% by weight of aromatic (meth) acrylate units and 20 to 95% by weight of methyl methacrylate units, and the weight average molecular weight of the copolymer is 5000 to 30000,
The laminated body characterized by this is provided.

  The laminate of the present invention has high surface hardness, antibacterial properties, and excellent hue. For this reason, applications where scratches on the surface of molded products are avoided and transparency is required and functions such as comfort, cleanliness, and safety are required, such as components for displays, household appliances, stationery, etc. It is suitably used for Further, by using an expensive surface hardness improver and antibacterial agent as the surface layer material, the surface hardness and antibacterial properties are efficiently improved, and the cost is excellent.

  Examples of the transparent synthetic resin (A) used as the base material of the present invention include transparent thermoplastic resins such as a polycarbonate resin and a polymethyl methacrylate resin. In particular, considering the recycling of the laminate, the polycarbonate resin composition (B) is used as the surface layer material, and therefore, the polycarbonate resin is preferably used as the base material.

  As for the viscosity average molecular weight of polycarbonate resin used as a base material, 20000-30000 are preferable. When the viscosity average molecular weight is less than 20000, the impact strength of the laminate may be inferior. On the other hand, if it exceeds 30000, the moldability may decrease. Preferably it is the range of 22000-28000.

The above viscosity average molecular weight is 0.5 wt% polycarbonate resin solution using methylene chloride as a solvent, the specific viscosity (η _sp ) is measured at a temperature of 20 ° C. using a Cannon-Fenske type viscosity tube, and the intrinsic viscosity is converted by concentration conversion. [Η] was obtained and calculated from the following SCHNELL equation.
[Η] = 1.23 × 10 ⁻⁴ M ^0.83

  The polycarbonate resin used for the surface layer material or the base material of the present invention is a phosgene method in which various dihydroxydiaryl compounds and phosgene are reacted, or an ester in which dihydroxydiaryl compounds are reacted with a carbonate ester such as diphenyl carbonate. Typical examples of the polymer obtained by the exchange method include a polycarbonate resin produced from 2,2-bis (4-hydroxyphenyl) propane (bisphenol A).

  Examples of the dihydroxydiaryl compound include bisphenol 4-, bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, 2,2-bis (4-hydroxyphenyl) butane, 2, 2-bis (4-hydroxyphenyl) octane, bis (4-hydroxyphenyl) phenylmethane, 2,2-bis (4-hydroxyphenyl-3-methylphenyl) propane, 1,1-bis (4-hydroxy-3) -Tert-butylphenyl) propane, 2,2-bis (4-hydroxy-3-bromophenyl) propane, 2,2-bis (4-hydroxy-3,5-dibromophenyl) propane, 2,2-bis ( Bis (hydroxyaryl) alkanes such as 4-hydroxy-3,5-dichlorophenyl) propane, 1,1- (4-hydroxyphenyl) cyclopentane, bis (hydroxyaryl) cycloalkanes such as 1,1-bis (4-hydroxyphenyl) cyclohexane, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxy-3 Dihydroxy diaryl ethers such as 3,3'-dimethyldiphenyl ether, dihydroxy diaryl sulfides such as 4,4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxydiphenyl sulfoxide, 4,4'-dihydroxy-3,3 ' Dihydroxy diaryl sulfoxides such as dimethyldiphenyl sulfoxide, dihydroxy diary such as 4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfone Sulfone, and the like.

These can be used alone or in admixture of two or more. In addition to these, piperazine, dipiperidyl hydroquinone, resorcin, 4,4'-dihydroxydiphenyl, and the like may be mixed and used.

  Furthermore, the above dihydroxyaryl compound and a trivalent or higher phenol compound as shown below may be used in combination. Trihydric or higher phenols include phloroglucin, 4,6-dimethyl-2,4,6-tri- (4-hydroxyphenyl) -heptene, 2,4,6-dimethyl-2,4,6-tri- (4 -Hydroxyphenyl) -heptane, 1,3,5-tri- (4-hydroxyphenyl) -benzol, 1,1,1-tri- (4-hydroxyphenyl) -ethane and 2,2-bis- [4 4- (4,4'-dihydroxydiphenyl) -cyclohexyl] -propane and the like.

  The viscosity average molecular weight of the polycarbonate resin (B1) used for the surface layer material of the present invention is usually 10,000 to 100,000, preferably 19000 to 33000, and more preferably 23,000 to 30000. In producing such a polycarbonate resin, a molecular weight regulator, a catalyst and the like can be used as necessary.

  The surface hardness improver (B2) used in the present invention is a copolymer comprising 5 to 80% by weight of aromatic (meth) acrylate units and 20 to 95% by weight of methyl methacrylate units. The weight average molecular weight of the coalescence is 5000-30000. In the present specification, (meth) acrylate means acrylate or methacrylate.

Examples of the aromatic (meth) acrylate include phenyl (meth) acrylate and benzyl (meth) acrylate. These can be used alone or in combination of two or more. Of these, phenyl methacrylate and benzyl methacrylate are preferable, and phenyl methacrylate is more preferable.

If the content of the aromatic (meth) acrylate unit in the surface hardness improver (B2) is 5% by weight or more, transparency is maintained, and if it is 80% by weight or less, a phase with the polycarbonate resin (B1) is maintained. Since the capacity is not too high and the transferability to the surface of the molded body is not lowered, the surface hardness is not lowered, which is preferable. Moreover, if the content rate of an aromatic (meth) acrylate unit is the range of 20 to 70 weight%, it is still more preferable from expressing high surface hardness, maintaining transparency further.

  The surface hardness improver (B2) may contain other monomer units other than the aromatic (meth) acrylate unit and the methyl methacrylate unit, if necessary. Examples of other monomers constituting other monomer units include methacrylates such as ethyl methacrylate, butyl methacrylate, propyl methacrylate, 2-ethylhexyl methacrylate; methyl acrylate, ethyl acrylate, butyl acrylate, propyl acrylate, 2- Acrylates such as ethylhexyl acrylate and glycidyl acrylate; vinyl cyanide monomers such as acrylonitrile and methacrylonitrile; diene monomers such as butadiene, isoprene and dimethylbutadiene; vinyl ether ethers such as vinyl methyl ether and vinyl ethyl ether Body; carboxylic acid vinyl monomers such as vinyl acetate and vinyl butyrate; olefin monomers such as ethylene, propylene and isobutylene; acrylic acid, methacrylic acid and male Ethylenically unsaturated carboxylic acid monomers such as acid and itaconic acid; vinyl halide monomers such as vinyl chloride and vinylidene chloride; maleimides such as maleimide, N-phenylmaleimide, N-cyclohexylmaleimide and N-methylmaleimide Monomers; Examples include cross-linking agents such as allyl (meth) acrylate, divinylbenzene, and 1,3-butylene dimethacrylate. Of these, methacrylate, acrylate, and vinyl cyanide monomer are preferable, and acrylate is more preferable from the viewpoint of suppressing thermal decomposition of the surface hardness improver (B2). These monomers can be used alone or in combination of two or more.

  When other monomer units are contained, the constituent monomers of the surface hardness improver (B2) are aromatic (meth) acrylate units of 5-79.9% by weight, methyl methacrylate units of 20-94.9% by weight. And other monomer units in the range of 0.1 to 10% by weight.

  As a monomer polymerization method for obtaining the surface hardness improver (B2), a known method such as an emulsion polymerization method, a suspension polymerization method, a solution polymerization method, a bulk polymerization method, or the like can be used. A suspension polymerization method and a bulk polymerization method are preferable, and a suspension polymerization method is more preferable. Further, additives necessary for the polymerization can be appropriately added as necessary, and examples thereof include a polymerization initiator, an emulsifier, a dispersant, and a chain transfer agent.

  The weight average molecular weight of the surface hardness improver (B2) is 5,000 to 30,000. When the weight average molecular weight is in the range of 5000 to 30000, the compatibility with the polycarbonate resin (B1) is good and the effect of improving the surface hardness is excellent. In addition, Preferably it is the range of 10,000-25000.

The weight average molecular weight is measured using gel permeation chromatography (GPC), and the detailed conditions are as follows:
As the GPC column, PLgel 5 μm MIXED-C manufactured by Agilent Technologies was used. THF was used as the mobile phase.

  The antibacterial agent (C) containing glass that elutes silver ions used in the present invention as an essential component is composed of a glass composition that can elute silver ions. In particular, the composition is preferably a polyhedron including silver oxide, phosphorus oxide, and zinc oxide. When the shape is a polyhedron, since it is easy to orient in a certain direction in the resin, it can be uniformly and easily mixed and dispersed in the resin, and light scattering is suppressed, which is preferable because of excellent transparency. .

The glass composition of the antibacterial agent (C) is preferably composed of Ag ₂ O in a range of 0.2 to 5% by weight, P ₂ O ₅ in a range of 30 to 80% by weight and ZnO in a range of 30 to 50% by weight. Is done. Further, this _B 2 _{O 3} may be contained a 0.1 to 15 wt% and / or CaO in the range of 0.1 to 15 wt%. In the former case, silver ions can be stably released and the transparency of the glass can be improved. In the latter case, a glass excellent in transparency and mechanical strength can be obtained.
When CaO is contained, the weight ratio of CaO to ZnO (ZnO / CaO) is more preferably in the range of 1.1-15.

  Moreover, in order to maintain the transparency of the resin, it is preferable that the average particle size of the glass composition be in the range of 0.1 to 300 μm. The antibacterial glass is readily available as a commercial product, and examples thereof include KM10D manufactured by Sinanen Zeomic.

  The compounding amount of the antibacterial agent (C) is 0.05 to 1.5 per 100 parts by weight of the resin component consisting of 35 to 75% by weight of the polycarbonate resin (A) and 25 to 65% by weight of the surface hardness improver (B). Parts by weight. If the blending amount is less than 0.05 parts by weight, it is difficult to obtain a sufficient antibacterial effect. On the other hand, when the amount exceeds 1.5 parts by weight, the transparency is impaired. More preferably, it is the range of 0.1-1.0 weight part.

  Furthermore, various resins, antioxidants, fluorescent brighteners, pigments, dyes, carbon black, fillers, mold release agents, polycarbonate resin composition (B) of the present invention, as long as the effects of the present invention are not impaired. You may mix | blend an antistatic agent, rubber | gum, a softening material, spreading agents (liquid paraffin, epoxidized soybean oil etc.), a flame retardant, additives, such as an organometallic salt, polytetrafluoroethylene resin for dripping prevention, etc.

  Examples of the various resins include polystyrene, high impact polystyrene, ABS, AES, AAS, AS, acrylic resin, polyamide, polyethylene terephthalate, polybutylene terephthalate, polyarylate, polysulfone, and polyphenylene sulfide resin. Or you may use together by 2 or more types.

Examples of the antioxidant include phosphorus antioxidants and phenolic antioxidants. Of these, hindered phenolic antioxidants are preferably used. For example, pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], thiodiethylene-bis [ Examples include 3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate. In particular, a compound represented by the following formula 1 is preferably used. Examples of the antioxidant include Irganox 1076 manufactured by Ciba Specialty Chemicals.
General formula 1

  As a compounding quantity of a hindered phenolic antioxidant, it is 0.05-1 per 100 weight part of resin components which consist of polycarbonate resin (B1) 35-75 weight% and surface hardness improver (B2) 25-65 weight%. 0.0 part by weight is preferable, and more preferably in the range of 0.1 to 0.8 part by weight.

  As a method for producing the laminate of the present invention, the resin compositions used for the base material and the surface layer material are melt-kneaded using separate single-screw or twin-screw extruders, and the respective melts are used for coextrusion. A so-called co-extrusion method in which the substrate is fed and laminated to the substrate feed block and the surface layer feed block of the die, or a method of laminating the plate-shaped molded product of the substrate and the surface layer by hot pressing, a method of laminating the surface layer into a film Can be mentioned. Of these, the coextrusion method is preferably used because of its excellent production efficiency.

  The thickness of the laminate is preferably 0.1 to 2 mm, more preferably 0.2 to 1 mm, and still more preferably 0.4 to 1 mm, considering the rigidity of the laminate. The thickness of the surface layer material is preferably 50 to 700 μm, more preferably 50 to 500 μm, and still more preferably 50 to 140 μm.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. In the examples, “parts” and “%” are based on weight unless otherwise specified.

Details of the raw materials used are as follows.
Polycarbonate resin used for the substrate:
Caliber 200-13 made by Sumika Stylon Polycarbonate
Polycarbonate resin synthesized from bisphenol A and phosgene (viscosity average molecular weight: 21500)
Polycarbonate resin (B1) used for the surface material:
Caliber 200-3 manufactured by Sumika Stylon Polycarbonate
Polycarbonate resin synthesized from bisphenol A and phosgene (viscosity average molecular weight: 28500, hereinafter abbreviated as “PC”)
Surface hardness improver (B2):
Mixture of methyl methacrylate and acrylic resin (Metbrene H-880 manufactured by Mitsubishi Rayon Co., Ltd., containing 5 to 80% by mass of aromatic (meth) acrylate units and 20 to 95% by mass of methyl methacrylate units, and having a mass average molecular weight of 5000 to 5000 A surface hardness improver containing a polymer of 30000, hereinafter abbreviated as “B2”)
Antibacterial glass (B3):
KM10D manufactured by Sinanen Zeomic (hereinafter abbreviated as “antibacterial agent”)
Antioxidant:
Irganox 1076 (hereinafter abbreviated as AO) manufactured by Ciba Specialty Chemicals

The extruder used was as follows.
Extruder for polycarbonate resin composition (B) as surface layer material:
Nippon Steel Works TEX30α twin screw extruder (L / D = 42, Φ = 30mm)
Extruder for coextrusion:
Extruder for substrate: VS40 single screw extruder manufactured by Tanabe Plastics
(L / D = 32, 40Φ)
Extruder for surface layer material: PEX-25-24 type single screw extruder manufactured by Pla Giken
(L / D = 24, 25Φ)

(Creation of resin composition pellets for surface material)
The above-mentioned various raw materials were each put into a tumbler at the blending ratios shown in Table 1 and Table 2, and after dry mixing for 10 minutes, the above extruder was used to melt and knead at a melting temperature of 240 ° C to obtain pellets It was.

(Processing by coextrusion method)
The obtained pellets of the resin composition for the surface layer material were pre-dried using a hot air circulation dryer under the drying conditions of 100 ° C. × 6 hours. The polycarbonate resin for the substrate was pre-dried under drying conditions of 120 ° C. × 4 hours.
The preliminarily dried polycarbonate resin pellets for base material were melt kneaded under the condition of 260 ° C. using the above base material extruder and supplied to the base material feed block of the coextrusion die. At the same time, the pre-dried pellets of the resin composition for the surface layer material are melt-kneaded under the condition of 260 ° C. using the above surface layer material extruder and supplied to the surface layer feed. Obtained. In addition, the thickness of the surface layer material and base material of the laminated body shown in Table 1 and Table 2 was set to 100 μm and 0.9 mm, respectively.

The evaluation method is as follows.
(Hue)
The obtained laminate was cut into 3 cm × 3 cm to prepare test pieces. Using the obtained test piece, Yellowness Index (YI) was measured with a spectrophotometer (CMS35-SP manufactured by Murakami Color Research Laboratory) under the conditions of a D65 light source and a viewing angle of 10 °.
A YI of 3.0 or less was considered good. The results are shown in Tables 1 and 2.

(Pencil hardness)
Using the test piece of the obtained laminate, the test piece on the surface material side of the laminate with a pencil hardness measuring machine (pencil scratch coating film hardness tester manufactured by Toyo Seiki Co., Ltd.) according to JIS K5600-5-4. The pencil hardness at which no scratches were observed on the surface was determined. A pencil hardness of HB or higher was considered good.

(Haze value)
Using the test piece of the obtained laminate, the haze value (H) was determined with a haze meter (HM150 manufactured by Murakami Color Research Laboratory Co., Ltd.) according to JIS K7105. The haze value (H) was calculated according to the following formula.
Haze value H (%) = (diffuse transmittance Td / total light transmittance Tt) × 100
A haze value (H) of 3.0% or less was considered good.

(Antibacterial)
The antibacterial test was conducted based on JIS Z 2801 (film adhesion method). More specifically, the surface of the initial coloring properties evaluation and similar conditions flat test pieces obtained in (cylinder temperature 270 ° C.), was added dropwise a bacterial suspension containing 10 ⁵ E. coli, PE-made film thereon The cells attached to the PE film and the flat plate test piece after washing at 35 ° C. for 24 hours were washed with an SCDLP medium, transferred to a petri dish, and cultured at 35 ° C. for 45 hours. ) Was counted. The evaluation standard is log ₁₀ (when the number of viable Escherichia coli counted by the film adhesion method using a flat plate test piece made of the resin composition not containing the antibacterial agent (B) of the present invention is x. x / y) (hereinafter abbreviated as antibacterial activity value) was 2.0 or more as good (◯), and less than 2.0 as bad (x).
Further, except for changing Escherichia coli to Staphylococcus aureus, the antibacterial activity test was carried out under the same operation and conditions as described above, the antibacterial activity value was obtained, and evaluated according to the same criteria. The respective results are shown in Tables 1 and 2.

判定： ○： 良好 ×：不良

Judgment: ○: Good ×: Bad

判定： ○： 良好 ×：不良

Judgment: ○: Good ×: Bad

As shown in Examples 1 to 6, those satisfying the constituent requirements of the present invention satisfied the required performance.
On the other hand, as shown in Comparative Examples 1 to 4, those that do not satisfy the constituent requirements of the present invention have the following drawbacks.
In Comparative Example 1, the antibacterial property was poor when the amount of the antibacterial agent was less than the specified amount.
In Comparative Example 2, the amount of the antibacterial agent was larger than the specified amount, and YI and haze value were poor.
In Comparative Example 3, when the blending amount of B2 (surface hardness improver) was less than the specified amount, the pencil hardness was poor.
In Comparative Example 4, the blending amount of B2 (surface hardness improver) was larger than the prescribed amount, and YI and haze value were poor.

Claims (4)

In a laminate formed by laminating a surface layer material made of a polycarbonate resin composition (B) on at least one surface of a base material made of a transparent synthetic resin (A),
The glass in which the polycarbonate resin composition (B) elutes silver ions per 100 parts by weight of the resin component consisting of 35 to 75% by weight of the polycarbonate resin (B1) and 25 to 65% by weight of the surface hardness improver (B2). An antibacterial agent (B3) as an essential component is a resin composition containing 0.05 to 1.5 parts by weight,
The surface hardness improver (B2) is a copolymer composed of 5 to 80% by weight of aromatic (meth) acrylate units and 20 to 95% by weight of methyl methacrylate units, and the weight average molecular weight of the copolymer is 5000 to 30000,
A laminate characterized by the above.   The laminate according to claim 1, wherein the resin component of the polycarbonate resin composition (B) comprises 45 to 65% by weight of a polycarbonate resin (B1) and 35 to 55% by weight of a surface hardness improver (B2). body.   The laminated body according to claim 1, wherein the shape of the glass eluting silver ions contained in the antibacterial agent (B3) is a polyhedron.   The laminate according to claim 1, wherein the transparent synthetic resin (A) is a polycarbonate resin.