JPH0691828A - Light diffusible methacrylic resin laminated sheet excellent in antistatic properties - Google Patents

Abstract

PURPOSE:To obtain a fire retardant light diffusible methacrylic resin laminated sheet excellent in antistatic properties by laminating a coating resin compsn. consisting of polyether esteramide and a methacrylic resin to a light diffusible methacrylic resin layer consisting of a methacrylic resin, a phosphorus type fire retardant, one of inorg. and org. light diffusing agents, and an ultraviolet absorber. CONSTITUTION:A light diffusible methacrylic resin layer is composed of a light diffusible methacrylic resin compsn. consisting of a methacrylic resin, a phosphrus type fire retardant, at least one of inorg. and org. light diffusing agents; and an ultraviolet absorber. A coating resin compsn. layer consists of 1-70wt.% of polyether esteramide and 30-99wt.% of a methacrylic resin. A light diffusible methacrylic resin laminated sheet wherein the coating resin compsn. layer is laminated to the single surface or both surfaces of the light diffusible methacrylic resin layer is obtained by simultaneously extruding the raw materials of the light diffusible methacrylic resin layer and the coating resin layer to form the extrudate into a sheet. The thickness of the coating resin layer of the light diffusible methacrylic resin laminated sheet is set to 5mum or more.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light-diffusing methacrylic resin laminate which is flame-retardant and has excellent antistatic properties. INDUSTRIAL APPLICABILITY The resin laminated plate of the present invention is used for covers such as general lighting equipment, emergency lights, guide lights, and indicator lights, display plates, or translucent covers, and also for signboards, signs, and screens of video equipment.
It can be used for

[0002]

BACKGROUND OF THE INVENTION Methacrylic resins have excellent transparency, weather resistance and mechanical strength and are widely used today. Furthermore, for example, in the field of applications such as lighting covers and signboards, in order to prevent see-through of the built-in fluorescent lamp and control the brightness of the face plate, methacrylic resin which is originally transparent is used, and inorganic materials with a different refractive index from this are used. Or, by adding fine particles of an organic substance, light diffusing property is imparted, and it is often used after being converted into semitransparent or opaque.

However, the methacrylic resin is also known as a resin which is relatively flammable, and there is a problem that it is difficult to apply it to applications requiring flame retardancy. In addition, methacrylic resin generally has the property of being easily charged,
Not only will the appearance be impaired by the adhesion of dust,
It has been pointed out that there is a problem that it becomes a hindrance during the heat processing of g.

In order to impart light diffusibility, a method is known in which methacrylic resin is blended with transparent fine particles having different refractive indexes. For example, JP-A-62-273230 discloses barium sulfate, calcium carbonate, quartz, crystalline silica, amorphous silica, glass, lithium fluoride, calcium fluoride and aluminum hydroxide as transparent inorganic fine particles. Japanese Patent Laid-Open No. 61-159440 discloses, as an organic light diffusing agent, a cross-linked polymer of alkyl methacrylate / aromatic vinyl / alkyl acrylate having a particle diameter of 30 to 300 μm.

On the other hand, many proposals have been made so far on making the methacrylic resin flame-retardant, and the methacrylic resin is made flame-retardant without significantly impairing the original characteristics of the methacrylic resin such as weather resistance, transparency and mechanical strength. The most proposed method is to blend an organic compound containing a halogen element and a phosphorus element in the molecule. For example, JP-B-56-26264 discloses a composition comprising a polymer containing methyl methacrylate as a main component, a halogen-containing polyphosphonate, an orthophosphoric acid triester, and a halogen-containing phosphorous acid triester. Kaisho 59-
No. 206454 discloses a composition comprising a methacrylic resin, a halogen-containing polyphosphonate, and a halogen-containing polyphosphate, and JP-A-61-115950 discloses a composition comprising a methacrylic resin, a chlorine-containing phosphate ester, and tetrabromobisphenol A. Japanese Patent Laid-Open No. 3-106630 discloses an extruded plate whose composition is composed of methacrylic resin and tris (tribromo) neopentyl phosphate.

Furthermore, various proposals have been made as follows as a method for improving the antistatic property of the methacrylic resin. 1. A method of applying a silicon compound or the like to the surface of a molded product. 2. A method in which a surfactant is added to the resin and kneaded. 3. A method of chemically modifying a resin by copolymerizing a monomer having a hydrophilic group and / or an ionic group.

1. With regard to (1), a coating step for the molded product is required, which causes a cost problem, and the antistatic effect of the obtained resin is inferior in sustainability, and particularly, the effect is easily lost by running water such as rainfall. 2. For example, a compound having a sulfonic acid group or a method of kneading the compound with an ether in an acrylic resin (JP-A-47-26438),
A method of kneading a compound having a sulfonic acid group, polyoxyalkylene glycol and a specific phosphorus compound (Japanese Patent Publication No. 53-30724) has been proposed, but since a relatively large amount of polyether or the like is added, It is easy to bleed out on the surface of the molded product, which may damage the appearance and cause stickiness. Also, a method of kneading polyalkylene glycol and higher fatty acid monoglyceride (Japanese Patent Publication No.
No. 36865), and a method of using a specific phosphorus compound in combination (Japanese Patent Publication No. 53-15896, Japanese Patent Laid-Open No. 54-54).
However, since acrylic resin has a high glass transition temperature and low migration of monoglyceride to the surface of a molded article, it is necessary to add a large amount of the acrylic resin to achieve sufficient performance. It tends to cause stickiness and poor appearance. In addition, a method of kneading an alkyl sulfonate or an alkylbenzene sulfonate with a trialkyl phosphite has been proposed (Japanese Patent Laid-Open No. 24-48845). However, since a large amount of the alkyl sulfonate or the like is added to the resin, There is a problem that the composition is inferior in surface smoothness and appearance.

3. With regard to the above, for example, a composition comprising a copolymer of a sulfosuccinic acid ester-based monomer and an acrylic monomer and an acidic phosphoric acid ester or an alkylene oxide compound (JP-A-59-182837, 182).
No. 838) has been proposed, but in order to exhibit the antistatic property, it is necessary to copolymerize a relatively large amount of the above-mentioned special monomer, which causes a problem in cost, and the light resistance of the composition. Inferior in heat resistance and heat resistance.

[0009]

DISCLOSURE OF THE INVENTION In order to obtain a light-diffusing methacrylic resin plate which is flame-retardant and is excellent in antistatic property, the present inventors have added a flame-retardant agent, a light-diffusing agent and an antistatic agent to methacrylic resin. An attempt was made to knead the agent, extrude and process it into a sheet. However, when fine particles, particularly inorganic fine particles, are added in order to impart light diffusivity to the methacrylic resin, the resin becomes extremely easy to burn. To make a methacrylic resin containing such fine particles flame-retardant, Even with effective flame retardants such as organic compounds containing halogens and phosphorus, we faced the great difficulty of having to add in fairly large amounts. That is, a resin plate containing a large amount of a flame retardant is markedly deteriorated in heat resistance, weather resistance, light resistance, and mechanical strength, and is practically difficult to use.

Under such circumstances, a technique for imparting a light diffusing property to a methacrylic resin plate in which the flame retardant, the weather resistance, and the mechanical strength are less reduced or more preferably no reduction is achieved by reducing the addition amount of the flame retardant as much as possible. Was strongly desired. In addition, by kneading an antistatic agent such as polyethylene glycol or sodium alkylbenzene sulfonate into the methacrylic resin, although the initial antistatic performance can be imparted, for example, for lighting fixture cover applications that are used for a long period of time, it is charged. There is a problem in that the anti-static effect is inferior in durability, and particularly when the surface is wiped with water, the antistatic performance is significantly reduced, and it takes a long time to recover.

[0011]

Means for Solving the Problems As a result of diligent studies on techniques for imparting flame retardancy, antistatic properties, and light diffusibility to methacrylic resin, the present inventors have incorporated a phosphorus-based flame retardant into methacrylic resin, and By optimizing the addition amount of at least one of the inorganic and organic light diffusing agents, it was found that the light diffusivity can be imparted without lowering the flame retardance as compared with the conventional light diffusing resin composition, Furthermore, the present invention was completed based on the idea that a semi-permanent antistatic effect can be exhibited without lowering the mechanical strength and heat resistance of the base layer itself by laminating with a specific coating resin composition. Came to do.

That is, according to the present invention, one surface of the light diffusing methacrylic resin layer (A) comprising a methacrylic resin, a phosphorus flame retardant, at least one selected from inorganic and organic light diffusing agents, and an ultraviolet absorber, or Coating resin composition layer (B) comprising 1 to 70% by weight of polyetheresteramide and 30 to 99% by weight of methacrylic resin on both surfaces
And a light diffusing methacrylic resin laminated plate, wherein the film is laminated to a thickness of 5 μm or more.

As the methacrylic resin in the present invention, any one of the following or two of them can be used.
A mixture of two or more species can be used. That is, (a) methyl methacrylate unit 80 to 99% by weight and carbon number 1 to 8
A resin containing 1 to 20% by weight of an alkyl acrylate unit, 30 to 99% by weight of (b) methyl methacrylate unit and acrylic acid, methacrylic acid, maleic anhydride, maleimide, N-substituted maleimide, styrene. , At least one monomer unit 1 selected from α-methylstyrene
70% by weight of a resin, (C) a resin containing a 6-membered ring acid anhydride unit and / or a 6-membered ring imide unit represented by the following formula in the molecule.

[0014]

[Chemical 1]

[0015]

[Chemical 2]

The resin (a) consisting of a methyl methacrylate unit and an alkyl acrylate unit has excellent weather resistance and transparency, and is known by a radical polymerization method, that is, a suspension polymerization method, a solution. It can be produced by a polymerization method, a bulk polymerization method, or the like. Alkyl acrylate having 1 to 8 carbon atoms
Examples include methyl acrylate and ethyl acrylate
, N-propyl acrylate, n-butyl acrylate
, I-butyl acrylate, 2-ethylhexyl acrylate, and the like, and methyl acrylate, ethyl acrylate, and n-butyl acrylate are preferably used. If the proportion of methyl methacrylate units is less than 80% by weight, the heat-deformation resistance of the composition is largely reduced, resulting in 99%.
When the content is more than weight%, the thermal decomposition resistance is poor, and thus both are not preferable. (A) Resin in chloroform at 25 ℃
The reduced viscosity (ηsp / c) measured by 30-120 ml /
The range of g is preferable, and the range of 35 to 110 ml / g is particularly preferable. When the reduced viscosity is less than 30 ml / g, the mechanical strength of the composition is poor, and when it exceeds 120 ml / g,
Both are not preferable because they have poor fluidity and processability.

Among the resins listed in (b), the resin composed of a methyl methacrylate unit and styrene, and / or an α-methylstyrene unit has a lower hygroscopicity than that of the resin (a) and is excellent in molding. Has workability. Further, a resin composed of a methyl methacrylate unit and a monomer unit selected from acrylic acid, methacrylic acid, maleic anhydride, maleimide, N-substituted maleimide and α-methylstyrene is a methacrylic resin having high heat resistance. Also, it can be produced by a known radical polymerization method, that is, a suspension polymerization method, a solution polymerization method, a bulk polymerization method, or the like. When the ratio of the methyl methacrylate unit is less than 30% by weight, the weather resistance of the composition is poor, and when it exceeds 99% by weight, the thermal decomposition resistance is poor, which is not preferable. 2 in chloroform
As in the case of the resin (a), the reduced viscosity (ηsp / c) measured at 5 ° C. is preferably in the range of 30 to 120 ml / g.

The resin containing a 6-membered cyclic anhydride unit and / or a 6-membered cyclic imide unit in the molecule mentioned in (C) is characterized by having a considerably high heat resistance. As a manufacturing method, first, acrylic acid, methacrylic acid, t-butyl acrylate-
Or a homopolymer of t-butyl methacrylate,
Copolymers, or copolymers of at least one of these with other copolymerizable ethylenically unsaturated monomers, by known radical polymerization methods, that is, suspension polymerization methods, solution polymerization methods, bulk polymerization methods, etc. Producing and then heating this polymer under reduced pressure to cause ring closure reaction to form a 6-membered ring acid anhydride unit, or further reaction with ammonia or primary amine to form a 6-membered ring imide unit. Can be implemented by 2) in chloroform, similar to the resins of (a) and (b)
The preferred range of the reduced viscosity (ηsp / c) measured at 5 ° C is 30 to 120 ml / g.

As the phosphorus-based flame retardant used in the present invention, triaryl phosphate ester, diaryl phosphate ester, monoaryl phosphate ester, aryl phosphonate compound, aryl phosphine oxide compound,
Examples include condensed aryl phosphoric acid ester, halogenated alkyl phosphoric acid ester, halogen-containing condensed phosphoric acid ester, halogen-containing condensed phosphonic acid ester, halogen-containing phosphorous acid ester, and the like, or a mixture of two or more kinds thereof. . Specific examples include triphenyl phosphate, 9,10-dihydro-9-oxa-10.
-Phosphaphenanthrene-10-oxide, phenylphosphonic acid, tris (β-chloroethyl) phosphate, tris (dichloropropyl) phosphate, tris (tribromoneopentyl) phosphate, or compounds represented by the following structural formulas, etc. Is mentioned.

[0020]

[Chemical 3]

[0021]

[Chemical 4]

[0022]

[Chemical 5]

The methacrylic resin layer (A) of the present invention is a light diffusing methacrylic resin composition comprising a methacrylic resin, a phosphorus flame retardant, at least one selected from inorganic and organic light diffusing agents, and an ultraviolet absorber. Since the process of melting a product in an extruder and extruding it from a die is general, it is essential that the flame retardant itself to be added has good thermal decomposition resistance. That is, if a flame retardant that is easily pyrolyzed is used, retention in the extruder causes thermal decomposition or heat coloring during heating, and the extruded plate is colored, or bubbles or spots are generated on the plate surface,
Furthermore, the decomposition gas causes a problem that the environment of the manufacturing site is significantly deteriorated. Therefore, the flame retardant is used at a normal temperature for molding a methacrylic resin extruded plate, that is, about 230 to
A substance that hardly causes thermal decomposition at 280 ° C. is preferably used. From this viewpoint, tris (dichloropropyl) phosphate, tris (tribromoneopentyl) phosphate, aromatic condensed phosphoric acid ester and the like are preferable, and tris (tribromoneopentyl) phosphate is particularly preferable.

The amount of the phosphorus-based flame retardant added is preferably in the range of 1 to 20 parts by weight, more preferably 1 to 10 parts by weight, based on 100 parts by weight of the methacrylic resin. When the addition amount is less than 1 part by weight, the flame retardancy of the composition or the extruded plate is low, and when it exceeds 20 parts by weight, the heat resistance, weather resistance, light resistance, and mechanical strength are deteriorated. It becomes big and not practical.

As a light diffusing agent for imparting a light diffusing property to the methacrylic resin of the present invention, antimony trioxide, antimony pentoxide, barium sulfate, calcium carbonate, basic magnesium carbonate, titanium oxide, zinc oxide, aluminum oxide. , Aluminum hydroxide, magnesium hydroxide, zinc borate, quartz, crystalline silica, amorphous silica, glass beads, lithium fluoride, calcium fluoride, talc, mica, zeolite, hydrotalcite, wollastonite, tobermonite , Gyrolite, xonotlite,
Tobermorite, d-sonite, attapulgite, kaolin and other inorganic substances, and alkylmethacrylate / aromatic vinyl / alkylacrylate particle size 30 to
Examples include organic substances such as 300 μm crosslinked polymers and granular polyalkylsilsesquioxane resins. These can be used alone or in combination of two or more kinds. Particularly in the case of an inorganic substance, in order to improve the dispersibility in a methacrylic resin, a surface of the particle is often coated with a fatty acid or a silane treating agent. Further, when using the composition of the present invention as an extruded plate,
As for the light diffusing agent, as described above for the phosphorus-based flame retardant, the normal temperature for molding the methacrylic resin extruded plate,
That is, a substance that hardly causes thermal decomposition at about 250 to 280 ° C. is preferably used.

Further, among the above-mentioned light diffusing agents, there are some which can exhibit a flame retardant effect alone or in combination with a suitable flame retardant. It is also possible to reduce the amount of the flame retardant compounded while maintaining the flame retardancy of the plate. Examples of such a light diffusing agent include antimony trioxide, aluminum hydroxide, magnesium hydroxide, zinc borate and the like.

The selection of the type and blending amount of the light diffusing agent is extremely dependent not only on the optical characteristics of the composition or the extruded plate such as the light diffusing effect, the light transmittance and the presence or absence of "transparency", but also on the flame retardancy thereof. It should be noted that it has a significant impact. For example, barium sulfate is preferable from the viewpoint of price and ease of handling, and the dispersibility in resin is relatively good, but if it is not added in a large amount, it will not exhibit excellent hiding power and is flame-retardant to resin plates. There was a problem that it lowered. On the other hand, titanium oxide exerts an excellent hiding power when added in a small amount, but it is difficult to uniformly disperse it, and there is a problem that "translucency" is likely to occur.

The present inventors make full use of the characteristics of each light diffusing agent as described above, and without impairing the flame retardancy of the resin plate.
We have found that it is important to control the combination and addition amount of light diffusing agents in order to impart excellent light diffusing performance. For example, when barium sulfate is used, the addition amount thereof is preferably in the range of 0.1 to 3 parts by weight, more preferably 0.5 to 2 parts by weight, based on 100 parts by weight of the methacrylic resin. If the addition amount is less than 0.1 parts by weight, the light scattering performance is low and "transparent" is seen in the extruded plate, while if it exceeds 3 parts by weight, the flame retardant performance of the composition or the extruded plate is remarkably reduced. However, the amount of the flame retardant added must be increased, and the heat resistance and weather resistance are deteriorated, which is not preferable. Particularly, in the case of the display board of the evacuation guidance light, it is required that the total light transmittance is 30 to 35%. However, in order to achieve this transmittance, if barium sulfate is used alone to increase the addition amount. , The flame retardant performance will be reduced. Therefore, it is effective to use it in combination with titanium oxide whose light transmittance can be controlled by adding a small amount.
Here, the amount of titanium oxide added is 100
The range of 0.01 to 0.2 parts by weight is preferable, and the range of 0.05 to 0.18 parts by weight is more preferable. If the addition amount of titanium oxide is less than 0.01 parts by weight, it is difficult to uniformly disperse it in the resin and the light scattering performance is insufficient, while if it exceeds 0.2 parts by weight, it is disadvantageous in terms of cost. It is not preferable.

As the ultraviolet absorber in the present invention, 2
-(5-Methyl-2-hydroxyphenyl) benzotriazole, 2- [2-hydroxy-3,5-bis (α,
α-Dimethylbenzyl) phenyl] -2H-benzotriazole, 2- (3,5-di-t-butyl-2-hydroxyphenyl) benzotriazole, 2- [2-hydroxy-3,5-bis (α, α) -Dimethylbenzyl) phenyl] -2-benzotriazole, 2,2-methylenebis [4- (1,1,3,3-tetrabutyl) -6- (2
[H-benzotriazol-2-yl) phenol] and the like, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2,2′-dihydroxy-4-methoxybenzophenone system, salicylic acid Phenyl ester type, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1,2,2,6,6-pentamethyl)
Hindered amines such as 4-piperidyl) sebacate,
Further, 2- (3,5-di-t-butyl-4-hydroxybenzyl) -2-n-butylmalonate bis (1,2,2
2,6,6-pentamethyl-4-piperidyl), 1-
[2- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyloxy] ethyl] -4- [3
-(3,5-di-t-butyl-4-hydroxyphenyl) propionyloxy] -2,2,6,6-tetramethylpiperidine and the like have the same structure of hindered phenol and hindered amine in the molecule. Examples thereof include a hybrid type having these, and these can be used alone or in combination of two or more kinds. If a low-volatile UV absorber having a molecular weight of 400 or more is selected, the UV absorber may be volatilized and lost during molding of the extruded plate, or the roll may be contaminated by the volatilized UV absorber. It can be prevented and is more preferable.

The amount of the ultraviolet absorber added per 100 parts by weight of the methacrylic resin is preferably in the range of 0.02 to 10 parts by weight, more preferably 0.1 to 5 parts by weight.
If the addition amount is less than 0.02 parts by weight, the effect of improving weather resistance is insufficient, while if it exceeds 10 parts by weight, the color tone of the resin plate deteriorates, and the ultraviolet absorber is generally expensive, which is disadvantageous in terms of cost. Is not preferable.

Further, together with these ultraviolet absorbers, for example, (2,2,6,6-tetramethyl-4) can be used as an antioxidant.
-Piperidyl) sebacate, bis (1,2,2,6,6)
It is also possible to use a hindered phenol such as -pentamethyl-4-piperidyl) sebacate or a phosphorus-containing compound such as triphenyl phosphate. In the methacrylic resin layer (A) in the present invention, various elastomers can be blended in order to improve the impact resistance of the laminate. Here, as the elastomer,
Polybutadiene, styrene / butadiene random copolymers, block copolymers consisting of styrene and butadiene units, acrylonitrile / butadiene copolymers, ethylene / propylene / non-conjugated diene copolymers, etc. So-called diene-based polymers with ethylenically unsaturated monomers Examples thereof include a graft copolymer obtained by graft-polymerizing a monomer, a polymer obtained by hydrogenating a diene polymer to reduce unsaturated bonds in the polymer, and an acrylic elastomer. These may be used alone or in admixture of two or more. In particular, when importance is attached to weather resistance and light resistance, an acrylic elastomer is suitable, and an acrylic polymer having a multilayer structure is particularly preferred.

Here, the multi-layered acrylic polymer means
Three layers consisting of methyl methacrylate, an alkyl acrylate having an alkyl group having 1 to 8 carbon atoms, and a graft-bonding monomer as essential components, and other vinyl monomer or polyfunctional cross-linking monomer as necessary. Or a polymer having a multi-layer structure of four or more layers. For example, hard layer-soft layer-
Hard layer having three-layer structure, hard layer-soft layer-hard layer-soft layer-hard layer having five-layer structure, soft layer-
It has a four-layer structure of hard layer-soft layer-hard layer, and basically has a three-layer structure of hard layer-soft layer-hard layer, with an intermediate layer in which the composition changes substantially at a constant rate between the layers. Tata (hard layer-middle layer-soft layer-hard layer, hard layer-soft layer-
Intermediate layer-hard layer, hard layer-intermediate layer-soft layer-intermediate layer-hard layer, etc., basically having a three-layer structure, in which the molecular weight of the outermost hard layer gradually decreases from the inside to the outside. Can be included. The particle diameter of the multi-layered acrylic polymer is preferably in the range of 0.05 to 0.5 μm, and more preferably in the range of 0.05 to 0.3 μm from the viewpoint of emulsion polymerization rate and stability of the polymerized latex.

When the elastomer is added, its amount is preferably 50 parts by weight or less based on 100 parts by weight of the methacrylic resin. When the amount added exceeds 50 parts by weight, heat resistance, weather resistance, light resistance, and flame retardancy are deteriorated, which is not practical. The methacrylic resin layer (A) of the present invention includes an organic resin layer, within a range that does not impair the effects of the invention.
Inorganic dyes and pigments, release agents, lubricants, optical brighteners, bluing agents and the like can be added.

The method for molding the methacrylic resin layer (A) of the present invention into a plate shape is not particularly limited, but it can be generally manufactured by extrusion molding. As a method for producing the extruded plate, a methacrylic resin, a phosphorus flame retardant, a light diffusing agent, and an ultraviolet absorber are sufficiently stirred and mixed by a drum blender, a Henschel mixer, or the like, and then an extruder with a T-die is directly used. Extruded into a plate with a plate, a method of continuously forming an extruded plate having a desired plate thickness, width and surface state, a method of once forming the composition into pellets and then forming an extruded plate by the same method, the ratio of additives Any method may be used, such as a method of extruding a compound having a high content to form concentrated pellets, then diluting the concentrated pellets with a methacrylic resin to a desired additive concentration and extruding again to form an extruded plate.

The coating resin composition layer (B) of the present invention comprises a polyether ester amide and a methacrylic resin.
Here, as the methacrylic resin, any one of (i), (b) and (c) described above in the item of the methacrylic resin layer (A), or a mixture of two or more thereof may be used. it can. In addition, the methacrylic resin layer (A)
The methacrylic resin in the coating resin composition layer (B) and the methacrylic resin in the same type or different types can be combined in any combination.

In the present invention, the polyether ester amide means a multi-block type copolymer in which polyamide is a hard segment and diols containing polyoxyalkylene glycol are a soft segment, and both are linked by an ester bond. . This is suitable as a constituent component of the coating resin composition layer (B) because it has high heat resistance, good compatibility with a methacrylic resin, and can exhibit an excellent antistatic effect even when added in a relatively small amount. It was a great contribution to the completion of the present invention.

As the polyether ester amide, the following are preferably used from the viewpoint of compatibility with methacrylic resin. That is, (a) at least 50
A polyamide-forming monomer containing wt% caprolactam, (b) a dicarboxylic acid having 4 to 20 carbon atoms, and (c) a polyoxyalkylene glycol and / or at least one α, ω-dihydroxy hydrocarbon, What is obtained by polycondensing a diol having a number average molecular weight of 500 to 4000 and containing 30% by weight or more of polyoxyethylene glycol in a composition such that the component (c) is 40 to 85% by weight. It is more preferable that the relative viscosity in meta-cresol measured at 30 ° C. is 1.5 or more. By polycondensing the components (a), (b) and (c), a polyamide chain having carboxyl groups at both ends formed from the component (a) and the component (b) and the diols of the component (c) are polyesters. Polyether ester amide is obtained as a multi-block type copolymer linked by a bond.

Among the components (a), examples of polyamide-forming monomers other than caprolactam include lactams having 6 or more carbon atoms such as lauryllactam, 1,1-aminoundecanoic acid, and 1,2-aminoundecanoic acid. Aminocarboxylic acids having 6 or more carbon atoms, or diamines such as hexamethylenediamine-adipate, hexamethylenediamine-sebacate, hexamethylenediamine-dodecanedioate, and hexamethylenediamine-isophthalate
Examples thereof include dicarboxylic acid salts, and these may be used alone or in combination of two or more kinds. The proportion of caprolactam in the component (a) is preferably 50% by weight or more, and 7
It is more preferably 0% by weight or more. 50 caprolactam
If it is less than wt%, the compatibility with the methacrylic resin is low and the antistatic effect is poor, which is not preferable. Further, the combined use of caprolactam and another polyamide-forming monomer inhibits crystallization of the formed polyamide chain and improves the fluidity and transparency of the coating resin composition, which is preferable.

Examples of the dicarboxylic acid having 4 to 20 carbon atoms as the component (b) include aliphatic dicarboxylic acids such as succinic acid, glutaric acid, adipic acid, sebacic acid and decanedicarboxylic acid, terephthalic acid and isophthalic acid. Examples thereof include aromatic dicarboxylic acids and alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid. These may be used alone or in combination of two or more.

A polyamide chain is formed from the above-mentioned components (a) and (b) during polycondensation, which becomes a hard segment in the polyether ester amide. This polyamide chain affects the heat resistance, mechanical strength, or compatibility with the methacrylic resin of the polyether ester amide. That is, the polyamide chain is preferably contained in the polyether ester amide in the range of 15 to 60% by weight (the content of the diols as the component (c) is therefore 85).
To 40% by weight) and 30 to 40% by weight are more preferable. When the content of the polyamide chain is less than 15% by weight, the antistatic performance when kneaded with the methacrylic resin is insufficient, while when it exceeds 60% by weight, the compatibility with the methacrylic resin is deteriorated. Is also not preferable.

The number average molecular weight of the polyamide chain is 400.
The range of 1 to 1500 is preferable, and the range of 500 to 1200 is more preferable. When the number average molecular weight is less than 400, the heat resistance of the polyether ester amide decreases, while
If it exceeds 1500, the transparency is inferior, which is not preferable. The component (c) is a diol composed of polyoxyalkylene glycol and / or at least one α, ω-dihydroxy hydrocarbon. Examples of the polyoxyalkylene glycol here include polyoxyethylene glycol, polyoxypropylene glycol, polyoxytetramethylene glycol, polyoxyhexamethylene glycol, or both end hydroxy group type block copolymers of ethylene oxide and propylene oxide. You can The polyoxyalkylene glycol also includes those obtained by copolymerizing other diols such as butanediol, propylene glycol, neopentyl glycol and hydroquinone as an ether component.

As the α, ω-dihydroxy hydrocarbon,
Polyolefin glycol, hydrogenated polybutadiene glycol, 1,3-propanediol, obtained by copolymerizing olefin and butadiene to hydroxylate both ends, and then subjecting carbon-carbon double bond to hydrogen addition reaction,
1,4-butanediol, neopentyl glycol,
Examples thereof include condensates such as 1,6-hexanediol, 1,4-bis (hydroxymethyl) cyclohexane and dibutylene glycol.

Of the above diols, polyoxyalkylene glycols other than polyoxyethylene glycol and α, ω-dihydroxy hydrocarbons have the action of reducing the hydrophilicity of the resulting polyetheresteramide,
Therefore, the hydrophilicity of the polyether ester amide can be adjusted by introducing these components. However, the content of polyoxyethylene glycol in the component (C) is preferably 30% by weight or more, and more preferably 50% by weight or more. If the amount of polyoxyethylene glycol is less than 30% by weight, the antistatic property of the obtained polyetheresteramide will be deteriorated, which is not preferable. Further, the number average molecular weight of the diols is preferably in the range of 500 to 4000, and 1000 to 3
The range of 000 is more preferable. Number average molecular weight is 500
If less than, heat resistance is poor because the molecular weight of the hard segment in the resulting polyether ester amide is low,
On the other hand, when the number average molecular weight is more than 4000, the transparency of the polyether ester amide is poor, which is not preferable.

The method for producing the polyether ester amide of the present invention is not particularly limited, but for example, the components (a), (b), and (c) described above can be replaced with (b) and (c).
The components are mixed in a ratio such that they are substantially equimolar, and water produced during the reaction is passed through a nitrogen gas in the reaction system, or the reaction system is depressurized to about 700 to 300 torr to react. While removing it to the outside of the system, preferably 150 to 300 ° C., more preferably 180 to 2
A method of dehydration polycondensation at 80 ° C. can be used. In such a method, the reaction can be performed while gradually raising the temperature.

As described above, by allowing esterification and amidation to proceed at the same time in the dehydration polycondensation process, it is possible to prevent coarse phase separation of each component, and to obtain a homogeneous and transparent polyester ester amide. You can The polyether ester amide obtained by such a polycondensation reaction can be recovered in a strand form or a sheet form by taking it out from the reaction system, cooling it.

When the components (a), (b), and (c) are dehydrated and polycondensed by the above-described method, a part of caprolactam is likely to remain unreacted. It is desirable to remove it. The reaction mixture from which the unreacted caprolactam has been removed can be further polymerized, if necessary, by postpolymerization under reduced pressure at a temperature of 200 to 300 ° C, preferably 230 to 280 ° C. In such post-polymerization, it is preferable to use a dehydration condensation catalyst such as titanium alkoxide or zirconium alkoxide because the reaction time can be shortened and thermal coloring of the polymer can be prevented. When using these catalysts, the presence of water in the system deactivates the catalyst, so it is advantageous to remove the water together with the unreacted caprolactam from the system before adding the catalyst.

The molecular weight of the polyetheresteramide of the present invention can be adjusted by selecting the reaction conditions, if necessary. As an index of the molecular weight, the relative viscosity measured at 30 ° C. in meta-cresol can be used, but it is preferably 1.5 or more, and more preferably 1.6 or more. When the relative viscosity is less than 1.5, the mechanical strength of the obtained polyetheresteramide is poor, which is not preferable.

As a method for laminating the coating resin composition layer (B) of the present invention on the light diffusing methacrylic resin layer (A),
Generally, a co-extrusion method or a laminating method is used. In any case, the methacrylic resin and the polyether ester amide forming the coating resin composition layer (B) are known methods,
For example, it is preferable to mix using a Henschel mixer, a Banbury mixer, a mixing roll, an extruder or the like. Here, the ratio of the methacrylic resin and the polyether ester amide in the coating resin composition layer (B) is 1 to 70% by weight, and 3 to 50% by weight.
Is preferred. When the proportion of the polyether ester amide is less than 1% by weight, the antistatic effect is insufficient, while when it exceeds 70% by weight, the mechanical strength of the coating resin composition layer (B) is lowered and the laminated sheet Since the surface condition of is inferior, neither is preferable.

An organic and / or inorganic electrolyte can be added to the coating resin composition layer (B) of the present invention in order to further improve the antistatic performance. That is, by using the polyether ester amide and the electrolyte together, a composition having more excellent antistatic performance can be obtained. Here, as the organic and / or inorganic electrolyte,
What was illustrated in Japanese Patent Application No. 2-51803 can be used. For example, dodecylbenzene sulfonic acid, p-toluene sulfonic acid, lauryl sulfonic acid, stearic acid, and their alkali metal salts or alkaline earth metal salts, quaternary ammonium salts such as trimethyloctyl ammonium bromide and tetrabutyl ammonium chloride,
Examples thereof include quaternary phosphonium salts such as amyltriphenylphosphonium bromide, and inorganic salts such as silver nitrate, potassium bromide, sodium bromide, potassium thiocyanate, which may be used alone or in combination of two or more. Is also good.

The amount of the organic and / or inorganic electrolyte added to the coating resin composition layer (B) of the present invention is preferably 10 parts by weight or less based on 100 parts by weight of the total of the methacrylic resin and the polyether ester amide, 0.01 to 5 parts by weight is more preferable. If the amount added exceeds 10 parts by weight, the mechanical strength of the coating resin composition layer (B) will decrease,
In addition, the surface condition of the laminated plate is also inferior, which is not preferable.

The addition of various heat stabilizers to the coating resin composition layer (B) of the present invention is particularly effective for improving the heat stability of the polyether ester amide. These heat stabilizers include N, N'-hexamethylene bis (3,5-di-t-butyl-4-hydroxycinnamic acid amide), 4,4'-bis (2,6-di-t -Butylphenol), 2,2'-methylenebis (4-ethyl-6-
t-butylphenol), pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], and other hindered phenols, N, N'-bis (β-naphthyl) ) -P-Phenylenediamine, aromatic amines such as poly (2,3,4-trimethyl-1,2-dihydroquinoline), sulfur-containing compounds such as dilaurylthiodipropionate, and phosphorus compounds. These heat stabilizers may be added during the polycondensation reaction of the polyether ester amide, or may be added during the mixing of the polyether ester amide with the methacrylic resin.

The addition of various ultraviolet absorbers to the coating resin composition layer (B) of the present invention is particularly effective for improving the weather resistance and light resistance of the polyether ester amide. Examples of the ultraviolet absorber are as described above, but these may be used alone or in combination of two or more kinds. The amount of the ultraviolet absorber added is 100 parts by weight of the total of the methacrylic resin and the polyether ester amide,
The range of 0.02 to 10 parts by weight is preferable, and the range of 0.1 to 5 parts by weight is more preferable. If the amount added is less than 0.02 part by weight, the effect of improving weather resistance is insufficient, while 10
If it exceeds the weight part, the color tone of the composition or the extruded plate is deteriorated, and the ultraviolet absorber is generally expensive, which is disadvantageous in terms of cost, which is not preferable.

In the coating resin composition layer (B) of the present invention, various pigments, dyes, reinforcing fillers, nucleating agents, lubricants, plasticizers, release agents, hardeners and hardeners are used as long as the object of the present invention is not impaired. The flame retardant or other polymers can be blended in any process such as a kneading process or a plate forming process. Here, as the reinforcing filler, glass fiber, carbon fiber, fibrous reinforcing agent such as potassium titanate or mica, talc, clay, calcium silicate, calcium carbonate, glass foil, glass beads, other polymer particles or A flaky filler can be mentioned.

A coating resin composition layer (B) on one side or both sides of the light diffusing methacrylic resin layer (A) of the present invention.
There is no particular limitation on the method for producing the light-diffusing methacrylic resin laminate in which the above are laminated. For example, a co-extrusion method in which the raw material resins of the light diffusing methacrylic resin layer (A) and the coating resin layer (B) are simultaneously melt extruded to form a sheet, or an extruded light diffusing methacrylic resin layer (A). ), The raw material resin of the coating resin layer (B) is melt extruded from a T-die and laminated, and the coating resin layer (B) previously formed into a film shape is heated on the light diffusing methacrylic resin layer (A). A method of continuously laminating between sheets of resin, a coating resin layer (B) formed into a film on the sheet-shaped light-diffusing methacrylic resin layer (A) is thermocompression-bonded by a press. Any method or the like can be used.

In the production of a laminated plate, the coextrusion method is excellent in that the fluidity of both layers can be matched and made uniform at the time of lamination, so that the adhesion of both layers is good and the molding distortion is similar. ing. In this co-extrusion method, two or three ordinary extruders are used, the substrate layer is melt-extruded from a large extruder such as 60 mmφ or 90 mmφ, and the coating layer is melt-extruded from a small extruder such as 30 mmφ or 40 mmφ. The thickness of the substrate layer and the coating layer can be controlled by adjusting the extrusion amount of two or three extruders and the distance between the rolls of the polishing roll on the exit side of the extruder. Further, it is necessary to match the fluidity with the substrate layer and the coating layer, and this can be performed by adjusting the temperature of each extruder and die.

The thickness of the light diffusing methacrylic resin laminate of the present invention is preferably 0.5 to 5 mm, more preferably 1 to 3 mm. If the plate thickness is less than 0.5 mm, mechanical strength problems such as insufficient rigidity of the plate occur, which is not preferable. The thickness of the coating resin layer (B) in the light diffusing methacrylic resin laminate of the present invention is preferably 5 to 500 μm, more preferably 10 to 200 μm.
If the thickness of the coating resin layer (B) is less than 5 μm, the antistatic performance of the resulting laminate will be insufficient, while if it exceeds 500 μm, the heat resistance and mechanical strength of the laminate will be reduced. Not preferable. In order to facilitate the measurement of the thickness of the coating resin layer (B) during the production of the laminated plate, it is effective to preliminarily mix a small amount of dye or fluorescent agent into the coating resin layer (B).

Further, in order to further improve the light diffusion effect of the methacrylic resin laminated plate of the present invention, it is also included in the present invention to provide the surface of the plate with unevenness such as embossing or prism processing. The methacrylic resin laminate of the present invention has a light diffusing property, is made flame retardant, and is also excellent in antistatic property and weather resistance, so that it is a lighting fixture cover, a signboard, an indicator light,
It is extremely useful for applications such as video equipment.

[0058]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto. The measurements in Examples and Comparative Examples were carried out using the method described below or a measuring instrument. (1) Total light transmittance A test piece of 50 × 50 mm was cut out from the extruded plate and JIS
It is measured according to the test method specified in K7105 (Plastic optical property test method). (2) Heat distortion temperature A test piece is cut out from the extruded plate and measured according to the method specified in ASTM D648. (3) Surface resistance A test piece was cut from the extruded plate and manufactured by Toa Denpa Kogyo "ULT
RA MEGOH MMETER MODEL SM-1
0E ", measured voltage at 23 ° C, 55% RH 500
V was applied for 30 seconds, and the surface resistance value after 45 seconds was measured. (4) Flame resistance A test piece having a length of 125 mm and a width of 12.5 mm is cut out from an extruded plate, and the flame resistance is evaluated according to the test method C stipulated in Annex 7 of JIL5502 "Technical Standard for Guide Light Fixtures". When the burning rate is 38 mm / min or less, it is determined to be flame retardant. (5) Weather resistance test The test piece was put in a mercury lamp irradiation test (high-speed light resistance test) in a 75
The change in appearance after exposure for 2 weeks at 0 ° C is visually evaluated.

The abbreviations used in Examples and Comparative Examples indicate the following compounds. MMA; methyl methacrylate MA; methyl acrylate LPO; lauroyl per-oxide n-OM; n-octyl mercaptan Further, unless otherwise specified, the following% and parts are respectively weight% and weight part.

[0060]

Example 1 [Preparation of methacrylic resin] 30 liters of ion-exchanged water was placed in a pressure reactor equipped with a stirring blade having an internal volume of 60 liters, and 150 g of tricalcium phosphate and 1.2 g of sodium lauryl sulfate were added as suspending agents. , Disperse, 7
The temperature was raised to 5 ° C. MMA 18.8kg, MA under stirring
A monomer mixture consisting of 1.2 kg, 40 g of LPO and 36 g of n-OM was charged and kept for 2 hours to complete the polymerization. The bead-shaped methacrylic resin (A1) thus obtained was washed with water and dried. The reduced viscosity (ηsp / c) measured at 25 ° C in chloroform was 70 ml / g. [Preparation of Polyether Esteramide] A stainless steel reactor having an internal volume of 10 liter equipped with a stirrer, a nitrogen introduction tube, a distillation tube, and a catalyst charging pot was placed in a polyoxyethylene glycol having a number average molecular weight of 1490 (1920 g) and sebacic acid (239 g). 1750 g of caprolactam, 117 g of hexamethylenediamine-adipate, and pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-
4-hydroxyphenyl) propionate] 8 g was charged, and while introducing nitrogen at a flow rate of 1 liter / min, 250
The reaction was carried out at 0 ° C for 3 hours.

Then, the pressure inside the reactor was gradually reduced to distill off unreacted caprolactam. Next, a solution prepared by dissolving 8 g of tetrabutoxyzirconium in 50 g of caprolactam was charged from the catalyst charging pot under reduced pressure, and the temperature was set to 260 ° C.
The reaction was continued for an additional 2.5 hours with Tall. The molten polymer after the reaction was taken out in a strand form from the bottom of the reactor, poured into water and cooled, and then cut using a pelletizer to obtain transparent polyetheresteramide (B1) chips. The soft segment content was 59% by weight, of which the polyoxyethylene glycol content was 80% by weight and the relative viscosity measured in metacresol at 30 ° C. was 2.1. [Preparation of coating resin composition] 10 parts by weight of polyether ester amide (B1), methacrylic resin (A1) 89.
5 parts by weight and 0.5 parts by weight of sodium dodecylbenzenesulfonate were mixed for 10 minutes using a drum blender, and a 30φ twin-screw extruder (AS3 manufactured by Nakatani Machinery Co., Ltd.) was mixed.
Melt extrusion was carried out using 0 type) to obtain pellets. The pellets were dried at 80 ° C. for 3 hours and then used in the following laminated plate coextrusion. [Preparation of Light-Diffusing Methacrylic Resin Composition] Using a Henschel mixer (FM10B type) manufactured by Mitsui Miike Kakoki Co., Ltd., 100 parts by weight of methacrylic resin (A1), tris (tribromoneopentyl) phosphate 5 Parts by weight,
Barium sulfate 1.3 parts by weight, titanium oxide 0.1 parts by weight,
Then, a mixture of 0.2 parts by weight of 2- (5-methyl-2-hydroxyphenyl) benzotriazole as an ultraviolet absorber was stirred and mixed for 90 seconds. This mixture was melt-kneaded by a twin-screw extruder (AS30 type) manufactured by Nakatani Kikai Co., Ltd. to prepare milky white pellets. [Preparation and Evaluation of Light-Diffusing Methacrylic Resin Laminate] The above coated resin composition pellets were used in a 30φ uniaxial extruder.
Also, the light-diffusing methacrylic resin composition pellets were
Coextrusion was carried out using a single screw extruder. The die uses a feed block type, the temperature of the extruder cylinder and the die is 240 to 250 ° C, and the total thickness of the laminated plate is 2 mm.
The opening of the die lip and the interval between the polishing rolls were adjusted so that The thickness of the coating resin composition layer is 2
A laminate having a width of about 50 cm was prepared while adjusting the discharge rate by the rotation speed of both extruders so as to be 5 μm. The results of evaluating the physical properties of the obtained laminate are shown in Table 1.

[0062]

Example 2 The procedure of Example 1 was repeated, except that the amount of tris (tribromoneontyl) phosphate was changed to 10 parts by weight when the light diffusing methacrylic resin composition was prepared. The results are shown in Table 1.

[0063]

Comparative Example 1 The procedure of Example 1 was repeated, except that tris (tribromoneopentyl) phosphate was not added when the light diffusing methacrylic resin composition was prepared. The results are shown in Table 1.

[0064]

[Comparative Example 2] When the light diffusing methacrylic resin composition was prepared, the compounding amount of barium sulfate was 5.0 parts by weight, titanium oxide was not compounded, and the compounding amount of tris (tribromoneopentyl) phosphate was 25 parts by weight. Example 1 except that parts are used
I went in the same way. The results are shown in Table 1.

[0065]

[Comparative Example 3] At the time of preparing a light diffusing methacrylic resin composition, the compounding amount of barium sulfate was set to 5.0 parts by weight, titanium oxide was not compounded, and the compounding amount of tris (tribromoneopentyl) phosphate was adjusted. Example 1 was repeated except that the amount was 7 parts by weight. The results are shown in Table 1.

[0066]

Comparative Example 4 The procedure of Example 1 was repeated except that the light diffusing methacrylic resin composition was extruded alone and no coating layer was provided. The results are shown in Table 2.

[0067]

Example 3 When the light diffusing methacrylic resin composition was prepared, the compounding amounts of barium sulfate and titanium oxide were each 1.6.
Parts by weight and 0.12 parts by weight, and the thickness of the laminate is 1.
The procedure of Example 1 was repeated except that the thickness of the coating layer was 5 mm and the thickness of the coating layer was 22 μm. The results are shown in Table 2.

[0068]

Comparative Examples 5 and 6 The procedure of Example 3 was repeated, except that the composition of the coating layer resin composition and the coating layer thickness were changed as shown in Table 2. The results are shown in Table 2.

[0069]

[Table 1]

[0070]

[Table 2]

[0071]

According to the present invention, it is possible to obtain a light-diffusing methacrylic resin laminate which is flame-retardant and has excellent antistatic performance. Here, since the antistatic performance is realized by laminating the coating resin composition layer containing the polyetheresteramide on the light-diffusing methacrylic resin layer which is the base, the physical properties of the base layer are almost deteriorated. Can exhibit excellent performance without Therefore, the laminated plate of the present invention can be used as various molded articles such as general lighting fixtures, emergency lights,
It can be used for a cover such as a guide light or an indicator light, a display plate, or a translucent cover, or a signboard, a sign, a screen of a video device, or the like.

Claims (1)

[Claims] 1. At least one selected from methacrylic resins, phosphorus flame retardants, inorganic and organic light diffusing agents,
And a light-diffusing methacrylic resin layer (A) composed of an ultraviolet absorber, on one or both sides thereof, a coating resin composition layer (B containing 1 to 70% by weight of polyetheresteramide and 30 to 99% by weight of a methacrylic resin). ) Is laminated to a thickness of 5 μm or more, and a light-diffusing methacrylic resin laminate.