JPH1044345A - Methacrylic resin product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To have stable antistatic performance when masks are peeled off for the use of a product and on other occasions by arranging the masks having specified adhesive force on both sides of a methacrylic resin plate containing an antistatic agent. SOLUTION: Masks with adhesive strength of 1-150g/50mm breadth at 50 deg.C are arranged on both sides of a methacrylic resin plate containing an antistatic agent. As the antistatic agent, for example, alkylsulfonate such as sodium heptylsulfonate, sodium octylsulfonate, and sodium nonylsulfonate and others are named. A backing and an adhesive material are combined in the mask which is pressed on the plate for use. Materials such as a polyethylene film and paper are used as the backing, and materials which are mainly composed of an ethylene vinyl acetate copolymer etc., are used as the adhesive material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a methacrylic resin product having excellent antistatic properties.

[0002]

2. Description of the Related Art Since methacrylic resin has excellent transparency and gloss, and retains excellent mechanical properties, workability, weather resistance, etc., it is widely used for various lighting equipment, decorative articles, nameplates and the like. Have been. However, since methacrylic resin has strong charging properties, it has a drawback that dust and dirt in the air adhere to it and impair the appearance.

In order to solve these drawbacks, for example, a method of adding an appropriate amount of a higher fatty acid monoglyceride, a polyalkylene glycol and a phosphite to a methacrylic resin (Japanese Patent Publication No. 53-15896) has an alkylene oxide group. A method of kneading a polymer of a vinyl compound (Japanese Patent Publication No. 58-3986), a method of blending a copolymer in which a polar group such as a sulfonate is introduced in the molecule (Japanese Patent Application Laid-Open No. 1882837/1984), Method of kneading an alkyl sulfonate (JP-A-61-16770)
Etc. have been proposed.

[0004]

However, it is possible to impart antistatic properties by the above-mentioned method. However, at the time of extrusion molding or after molding, the product is masked to form a product, and after loading and transferring, When used after removing the masking, the antistatic performance varies, making it difficult to obtain a certain quality. Therefore, an object of the present invention is to solve the above problems and to provide a methacrylic resin product having stable antistatic performance.

[0005]

Means for Solving the Problems The present inventors have conducted intensive studies to achieve the above object, and as a result, arranged a masking having a specific adhesive strength to methacrylic resin on the surface of a methacrylic resin plate. As a result, it has been found that, when used, antistatic performance is stably exhibited, and the present invention has been completed. That is, the present invention provides a methacrylic resin plate containing an antistatic agent on both sides of a 50 ° C.
A methacrylic resin product comprising a masking having an adhesive force of 1 to 150 g / 50 mm width.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The methacrylic resin in the present invention is a polymer comprising methyl methacrylate as a main component and a monomer copolymerizable therewith. Here, the monomer copolymerizable with methyl methacrylate includes, for example, methacrylates such as ethyl methacrylate and butyl methacrylate; acrylates such as methyl acrylate, ethyl acrylate and butyl acrylate; Vinyl compounds such as acrylonitrile; and maleimide compounds such as cyclohexylmaleimide. In order to impart impact resistance, acrylic rubber particles or diene rubber particles may be blended.

The methacrylic resin plate is manufactured as follows. That is, it is manufactured by melt-kneading a mixture of a methacrylic resin and an antistatic agent using an extruder, extruding a plate-like molten resin from a T-die, and forming the mixture with a cooling roll. The plate-like material also includes a plate-like material produced by injection molding or cast polymerization.

In the present invention, a multilayer board can be used as the methacrylic resin sheet. The multi-layer board may be one using a methacrylic resin alone, or one used in combination with a thermoplastic resin such as polycarbonate or polystyrene, as long as there is no problem in quality, for example, to improve weather resistance and beauty. A methacrylic resin may be disposed on the surface layer and another thermoplastic resin may be disposed on the inside.

[0009] In the case of a two-layer board, the multilayer board is generally manufactured as follows. That is, a methacrylic resin is extruded from a first extruder, a resin (including a methacrylic resin) containing an antistatic agent or the like is separately mixed with a Henschel mixer, and the mixture is extruded from a second extruder. After the two are merged in an adapter provided between them, a plate-like molten resin is extruded from a T-die and formed by a cooling roll.

In the present invention, the methacrylic resin sheet contains an antistatic agent. Examples of the antistatic agent include sodium heptylsulfonate, sodium octylsulfonate, sodium nonylsulfonate, and the like.
Sodium decyl sulfonate, sodium dodecyl sulfonate, sodium cetyl sulfonate, sodium octadecyl sulfonate, sodium diheptyl sulfonate, potassium heptyl sulfonate, potassium octyl sulfonate, potassium nonyl sulfonate, potassium decyl sulfonate, potassium dodecyl sulfonate , Potassium cetylsulfonate, potassium octadecylsulfonate, potassium diheptylsulfonate, lithium heptylsulfonate, lithium octylsulfonate, lithium nonylsulfonate, lithium decylsulfonate, lithium dodecylsulfonate, lithium cetylsulfonate, octadecylsulfonate Examples thereof include alkyl sulfonates such as lithium and lithium diheptyl sulfonate. The antistatic agent may be used alone or in combination of two or more.

As a method of adding an antistatic agent to a methacrylic resin plate, a predetermined antistatic agent is mixed with a mechacrylic resin by a Hensiel mixer or the like and then passed through an extruder or, if necessary, fed to a twin screw. This is done by passing through an extruder. The antistatic agent may be added as it is, but it has 8 to 22 carbon atoms to improve color unevenness and poor appearance.
You may add together using alcohol, phosphite, etc.

The amount of the antistatic agent to be added is as follows.
0.1 to 5 parts by weight is preferable with respect to 00 parts by weight. If the added amount of the antistatic agent is less than 0.1 part by weight, the antistatic effect tends to be insufficient, and if it exceeds 5 parts by weight, the secondary processing of the methacrylic resin sheet may cause mold stains and the like. Tend to be.

The antistatic agent is preferably contained in the entire layer or only the surface layer of the methacrylic resin sheet. When it is contained only in the surface layer, it may be only one surface of the methacrylic resin plate or both surfaces. In a multilayer board, an antistatic agent may be contained at least in a layer including a surface layer. The thickness of the surface layer is not particularly limited, but is usually 30 to 500 μm, preferably 50 to 300 μm.
m.

The methacrylic resin includes, in addition to the above components, an antioxidant, an ultraviolet absorber, a lubricant, a dye, a pigment, a light diffusing agent, a fluorescent whitening agent, and the like, which are used in producing a normal methacrylic resin. Plasticizers, flame retardants, release agents and the like can be added. There is no particular limitation on the timing of addition, but it may be added during polymerization, pelletization, or extrusion.

In the present invention, masking refers to a combination of a base material and an adhesive, which is used by pressing it to a resin plate. As a base material for masking,
In general, known materials such as polyethylene film and paper are used, and as an adhesive, ethylene vinyl acetate copolymer resin (EVA) and linear low density polyethylene resin (LLD) are used.
PE) or the like is used.

The methacrylic resin product of the present invention is obtained by arranging masking on both surfaces of a methacrylic resin plate containing an antistatic agent. In the present invention, it is necessary that the adhesive strength at 50 ° C. of the masking is 1 to 150 g / 50 mm width. If the adhesive strength at 50 ° C. of the masking is greater than 150 g / 50 mm width, the adhesive component remains on the surface of the sheet, or the antistatic component is removed toward the masking, and the antistatic performance becomes unstable. On the other hand, if the adhesive strength at 50 ° C. of the masking is less than 1 g / 50 mm width, the adhesive strength is so weak that it does not fulfill the role of protecting the original product of the masking.

In the present invention, the adhesive strength of the masking is 5
It is a value at 0 ° C. and refers to a value measured by a method described in Examples described later. A preferred range of the adhesive strength is 5 to 100 g / 50 mm width.

The masking is usually carried out in a temperature range of 10 to 80 ° C., and in a preferred embodiment of the extrusion molding method of a methacrylic resin plate, the masking is preferably carried out at 40 to 60 ° C.
Applied continuously at ℃. The masking may be applied at the time of forming the resin sheet or after forming the sheet.For example, in the case of the casting polymerization method, the product may be obtained by applying the masking to the prepared resin plate under the above temperature range. it can.

[0019]

EXAMPLES The present invention will be described below in detail with reference to examples, but the present invention is not limited to these examples. In addition,
In the examples, the evaluation was measured by the following method. (1) Surface specific resistance value A 50 mm square piece was cut out from the center of the test piece, the masking was peeled off, and the condition was conditioned for 48 hours or more in a constant temperature room at 23 ° C. and 50% RH. Total TR
-8601 (manufactured by Takeda Riken). (2) Maximum charging voltage, half-life The maximum charging voltage of the test piece prepared by the same method as in the above (1),
The half-life was measured with an honest meter S4104 (manufactured by Shishido Shokai). (3) Ash adhesion test Cut out 200 mm square from the center of the test piece, peel off the masking, leave it in the room, charge it with cloth or the like, and 10 m from the ash
The adhesion at a distance of m was represented by the following three symbols. ：: ash does not adhere at all △: ash adheres slightly ×: ash adheres (4) Adhesive strength 200 mm × 1 sample piece with masking attached
Cut to 00mm, 100m along 200mm side direction
A 50 mm wide cut (50 mm wide x 20 mm) at the center of the m side
0 mm length) was put in a masking, and then, at a constant temperature of 50 ° C., an autograph AG-10TB (manufactured by Shimadzu Corporation) was used.
Masking of 0 mm width part at 300 mm / min 180
゜ Peeled and the tension was determined. (5) Intrinsic Viscosity After a resin having a certain concentration was dissolved in chloroform, the resin was measured at 20 ° C. with an automatic viscometer.

Example 1 To 100 parts by weight of a methacrylic resin consisting of 94% by weight of methyl methacrylate and 6% by weight of methyl acrylate and having an intrinsic viscosity of 0.720 dl / g, 2 parts by weight of sodium decylsulfonate as an antistatic agent was added. After mixing with a mixer, the mixture was pelletized with an extruder having a cylinder diameter of 40 mm. The pellet is cooled through a roll with a gap adjusted so that it becomes a plate of 2 mm from a T-die with a cylinder diameter of 50 mm and a width of 400 mm, and EVA is used as an adhesive with an adhesive strength of 10 g / 50 mm width immediately before the take-up roll. The resultant was masked with polyethylene and cut into a thickness of 2 mm, a width of 400 mm, and a length of 1000 mm. Table 1 shows the antistatic performance of the obtained plate.

Examples 2 to 4 and Comparative Examples 1 to 3 The same procedures as in Example 1 were carried out except that polyethylene masking having a different adhesive strength was used. Table 1 shows the antistatic performance.

Examples 5 to 9 Instead of sodium decylsulfonate of Example 1, sodium heptylsulfonate (Example 5), sodium octylsulfonate (Example 6), potassium octylsulfonate (Example 7), decyl The preparation was performed in the same manner as in Example 1 except that potassium sulfonate (Example 8) and sodium dodecyl sulfonate (Example 9) were added and masking having different adhesive strength was used. Table 1 shows the antistatic performance.

Example 10 A methacrylic resin was extruded from a first extruder, and a methacrylic resin 1 consisting of 94% by weight of methyl methacrylate and 6% by weight of methyl acrylate having an intrinsic viscosity of 0.720 dl / g was prepared.
2 parts by weight of sodium decylsulfonate as an antistatic agent were added to 00 parts by weight, and a resin mixed with a Henschel mixer was extruded from a second extruder, and the two were combined in an adapter provided between the extruder and a die. It is cooled by passing through a roll having a gap adjusted to a plate of 2 mm from a T-die having a width of 400 mm, and a double-sided antistatic multilayer plate having a surface layer thickness of 200 μm and a plate thickness of 2 mm is applied immediately before a take-off roll. Apply 10g / 50mm polyethylene masking, thickness 2mm, width 400mm, length 100
It was cut to 0 mm. Table 1 shows the antistatic performance.

Examples 11 to 13 Instead of sodium decylsulfonate in Example 10, sodium heptylsulfonate (Example 11), sodium octylsulfonate (Example 12) and potassium octylsulfonate (Example 13) were added. However, the same operation as in Example 10 was performed except that masking having different adhesive strength was used. Table 1 shows the antistatic performance.

Comparative Examples 4 to 5 The same procedure as in Comparative Example 1 was carried out except that sodium heptylate (Comparative Example 4) and sodium dodecyl sulfonate (Comparative Example 5) were used instead of sodium decyl sulfonate in Comparative Example 1. . Table 1 shows the antistatic performance.

[0026]

[Table 1] ―――――――――――――――――――――――――――――――― Adhesive force Surface resistivity Maximum charge voltage Half-life Half-ash Test (g / 50mm width) (Ω / □) (V) (second) ―――――――――――――――――――――――――――――――― -Example 1 10 9.0 × 10 ¹³ 950 1 ２ 290 3.0 × 10 ¹⁴ 12203 340 2.0 × 10 ¹⁴ 12203 ○ 480 1.0 × 10 ¹⁴ 1170 2 ５ 5 10 9.5 × 10 ¹³ 960 1 ○ 620 9.1 × 10 ¹³ 930 1 ○ 720 9.6 × 10 ¹³ 950 1 ○ 830 9.3 × 10 ¹³ 910 1 ○ 9 10 9.1 × 10 ¹³ 910 1 10 10 9.5 × 10 ¹³ 920 1 １１11 20 9.2 × 10 ¹³ 930 1 １２12 20 9.2 × 10 ¹³ 920 1 １３13 30 9.0 × 10 ¹³ 920 1 ○ ―――――――――――――――――――――――――――――――― Comparative Example 1 180 2.8 × 10 ¹⁵ 1290 90 × 2 250 2.9 × 10 ¹⁵ 1280 85 × 3 300 2.6 × 10 ¹⁵ 1260 80 × 4 180 2.5 × 10 ¹⁵ 1260 80 × 5 180 3.0 × 10 ¹⁵ 1280 95 × ――――― ―――――――――――――――――――――――――――――

[0027]

EFFECT OF THE INVENTION The methacrylic resin product of the present invention is capable of stably exhibiting antistatic performance, has stable antistatic performance after storage, and is suitable for covers, decorative articles, nameplates of various lighting equipment and the like. Ideal for etc.

Claims (2)

[Claims] 1. A methacrylic resin plate containing an antistatic agent having an adhesive force at 50 ° C. of 1 to 150 g /
A methacrylic resin product comprising a masking having a width of 50 mm. 2. The methacrylic resin product according to claim 1, wherein the methacrylic resin plate is a multilayer plate having two or more layers.