JP2001279072A - Polyester resin composition for oa parts - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyester resin material that can be suitably used as parts in the OA machines that have the problems of toner adhesion, for example, printers, copying machines, facsimiles and the like. SOLUTION: The objective polyester resin composition for the parts of the OA machines is obtained by compounding (B) 1-30 wt.% of flame retardant and (C) 0.01-10 wt.% of a fluorinated alkyl ester polymer to (A) a polyester resin on the basis of the whole composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyester resin composition for OA parts, which is obtained by adding a flame retardant and a fluorinated alkyl ester polymer to a polyester resin. More specifically, in an electronic printing apparatus such as a printer, a copying machine, and a facsimile, a transfer body such as paper or a polyester film for transferring an electrostatic latent image is guided from a photosensitive drum to a transfer unit and further to a fixing unit. In addition, for a member that may cause disturbance of an image on a transfer member due to occurrence of toner adhesion, such as a transfer member guide member installed at a predetermined position in order to carry the toner out of the fixing unit, the prevention is performed. The present invention relates to a polyester resin composition for OA parts capable of improving stainability and preventing toner adhesion, and a molded product thereof.

[0002]

2. Description of the Related Art Polyester resin is a thermoplastic resin widely used in various fields such as packaging materials, electric / electronic parts, and automobile parts. In particular, polybutylene terephthalate and polyethylene terephthalate are excellent in heat resistance and excellent in mechanical properties, and are widely used for OA parts by utilizing their properties. Here, when used for mechanical components inside OA equipment, flame retardancy is often required in order to prevent fire and the like, and may be essential.

On the other hand, the above-mentioned polyester material is also used for a transfer member separating guide member installed at a predetermined position in an electronic printing apparatus such as a printer, a copying machine, a facsimile, etc. The toner before and after fixing may adhere. That is, before the fixing, the toner powder is still in a high temperature state after the fixing, and the toner that has not been completely solidified contacts and adheres to the member. Once the toner adheres to the member, the toner hardly comes off and the toner adheres as it is, so that the toner accumulated at a certain time may come off and stain the printed surface. In particular, when toner adheres to the separation guide member after the toner has been transferred to the transfer member, the toner is heated and fixed as it is. When the toner adheres to the member immediately after the fixing device, the toner adheres because the transfer member is heated. The toner is fixed on the transfer body,
The dirt is directly transferred to the transfer member, causing serious image disturbance.

Conventionally, no countermeasure has been taken against the above problem, or a metal or resin molded article coated with fluorine has been used. Although a fluorine coat is an effective means, it is disadvantageous in the process because a plurality of steps are added, and the surface coating treatment itself is very expensive, which has led to an increase in the price of the final product.

Therefore, there has been a demand for a method of simplifying or omitting the surface coating step and preventing toner adhesion by a relatively inexpensive method. On the other hand, for example, it is simply conceivable to add a fluorine-based additive such as polytetrafluoroethylene to a resin molded material for OA parts, but this is very expensive in terms of price, and In order to obtain a practical effect, it is necessary to add a large amount, and there is a disadvantage that the raw material cost becomes extremely high and it is not practical.

[0006]

Means for Solving the Problems In view of the above problems, the present inventors have conducted intensive studies. As a result, by adding a fluorinated alkyl ester polymer to a polyester resin containing a flame retardant, a relatively inexpensive polymer was obtained. Good water repellency and oil repellency are imparted by the method, the free energy of the molded product surface is reduced, and the antifouling property is improved, thereby preventing toner adhesion,
The present inventors have found that an extremely useful resin material for OA parts can be obtained, and have completed the present invention.

That is, the present invention relates to (A) a polyester resin, (B) 1 to 30% by weight of a flame retardant (in the whole composition), and (C) 0.01 to 10% by weight of a fluorinated alkyl ester polymer (total composition). OA component polyester resin composition obtained by adding and blending), and molded from the polyester resin composition,
An object of the present invention is to provide a molded part for OA, which is excellent in toner adhesion prevention.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the components of the resin material used in the present invention will be described in detail. First, the polyester resin (A), which is the base resin of the resin material of the present invention,
Polyester obtained by polycondensation of a dicarboxylic acid compound and a dihydroxy compound, polycondensation of an oxycarboxylic acid compound, or polycondensation of these three components, and the effects of the present invention are exerted on both homopolyesters and copolyesters.

Examples of the dicarboxylic acid compound constituting the thermoplastic polyester resin used herein include terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenyletherdicarboxylic acid, diphenylethanedicarboxylic acid, cyclohexanedicarboxylic acid, Known dicarboxylic acids such as adipic acid and sebacic acid and alkyl, alkoxy or halogen substituted products thereof. These dicarboxylic acid compounds can also be used in the polymerization in the form of a derivative capable of forming an ester, for example, a lower alcohol ester such as dimethyl ester. Two or more of these may be used.

Next, examples of the dihydroxy compound constituting the polyester resin of the present invention are as follows: ethylene glycol, propylene glycol, butanediol, neopentyl glycol, hydroquinone, resorcin, dihydroxyphenyl, naphthalene diol, dihydroxydiphenyl ether, cyclohexanediol, Dihydroxy compounds such as 2,2-bis (4-hydroxyphenyl) propane and diethoxylated bisphenol A, polyoxyalkylene glycols and their alkyl, alkoxy or halogen-substituted products, etc., which may be used alone or in combination of two or more. Can be.

Examples of oxycarboxylic acids include oxycarboxylic acids such as oxybenzoic acid, oxynaphthoic acid and diphenyleneoxycarboxylic acid, and alkyl, alkoxy or halogen-substituted products thereof. Further, derivatives of these compounds capable of forming an ester can also be used. In the present invention, one or more of these compounds are used.

In addition to these, polyesters having a branched or crosslinked structure using a small amount of a trifunctional monomer, that is, trimellitic acid, trimesic acid, pyromellitic acid, pentaerythritol, trimethylolpropane or the like may be used.

Aromatic compounds such as dibromoterephthalic acid, tetrabromoterephthalic acid, tetrachloroterephthalic acid, 1,4-dimethyloltetrabromobenzene, tetrabromobisphenol A, and ethylene or propylene oxide adduct of tetrabromobisphenol A Also included are polyester copolymers having halogens using compounds having a halogen compound as a substituent in the nucleus and having an ester forming group.

Further, a polyester elastomer constituting a block copolymer of a high melting point hard segment and a low melting point hard segment can also be used. Examples of the polyester elastomer include a block copolymer of a hard segment mainly composed of an alkylene terephthalate unit and a soft segment composed of an aliphatic polyester or polyether.

In the present invention, any of the thermoplastic polyesters produced by polycondensation using the above compounds as monomer components can be used as the base resin of the present invention, and can be used alone or in combination of two or more. Preferably, polyalkylene terephthalate, more preferably polybutylene terephthalate and a copolymer containing the same as a main component (a copolymer containing 50% by weight or more of a butylene terephthalate unit), polyethylene terephthalate and a copolymer containing the same as a main component Polymer (with ethylene terephthalate unit
A copolymer containing 50% by weight or more) or a mixture thereof is used. The polyester resin used in the present invention preferably has an intrinsic viscosity of 0.55 g / dl or more measured at 30 ° C. using O-chlorophenol as a solvent, more preferably 0.55 to 1.2 g / dl, particularly preferably 0.55 to 1.0 g / dl. dl is preferred.

Next, the flame retardant (B) used in the present invention
May be any flame retardant generally blended with thermoplastic polyester.

As the flame retardant, an organic halogen compound is generally used, and halogenated phenyl, halogenated diphenyl ether, halogenated aromatic bisimide compound, halogenated aromatic epoxy compound, low molecular weight organic halide of bisphenol A, halogenated polycarbonate,
Halogenated benzyl acrylate, halogenated polystyrene and the like are exemplified, and the halogen is generally preferably bromo.

When these flame retardants are used, it is preferable to use inorganic flame retardants in combination. Representative examples thereof include ammonium trioxide, ammonium tetroxide, ammonium pentoxide, sodium pyroantimonate, tin dioxide, and water. Examples include metal oxides and hydroxides such as aluminum oxide and magnesium hydroxide. The flame retardant aid is, for example, a silane-based, titanate-based,
It may be surface-treated with a coupling agent such as aluminum.

As the flame retardant, non-halogen flame retardants such as red phosphorus and phosphite can be used. When these are used, polycarbonate, phenol resin,
It is preferable to use a suitable flame retardant auxiliary such as melamine cyanuric acid in combination.

The flame retardant and the flame retardant auxiliary may be used alone or in combination of two or more.

In the present invention, the amount of the flame retardant (B) to be added is 1 to 30% by weight, preferably 3 to 20% by weight, based on the whole composition.
It is. An excessively large amount is not preferable because it impairs mechanical and physical properties, thermal stability and the like, and impairs the appearance of the resin. If the amount is too small, the flame retardancy becomes insufficient.

Note that, depending on the use of the molded article, UL standard 9
In some cases, a flame retardant category V-0 of 4 is required. In this case, it is preferable to use asbestos, a fluororesin, or the like together with the flame retardant. As the fluororesin, polytetrafluoroethylene, polychlorotrifluoroethylene,
Examples include homopolymers such as polyvinylidene fluoride, hexafluoropropylene, and perfluoroalkylvinyl ether, and copolymers containing units of ethylene, propylene, (meth) acrylate, and the like in the polymer. These may be used alone or as a mixture of two or more kinds. The amount of addition may be, for example, 0.1 to 10% by weight of the total composition, preferably,
0.1 to 5% by weight.

Next, in the present invention, a fluorinated alkyl ester polymer (C) is used. As the fluorinated alkyl ester polymer (C), a polymer other than the fluorinated alkyl ester (for example, a vinyl monomer) may be contained as a constitutional unit, but a perfluoroalkyl group-containing oligomer is preferable. Can be As the fluorinated alkyl ester polymer (C), commercially available products (manufactured by Dainippon Ink and Chemicals, Inc., trade name MEGAF)
AC ESM-1) can be used.

The fluorinated alkyl ester polymer is
Because it has excellent dispersibility compared to fluorine compounds such as polytetraethylene, it has the effect of lowering the free energy of the surface of a molded article equivalent or more with a small amount of addition and blending, reducing the interaction with the toner, A toner adhesion preventing effect is exhibited. In addition, since the addition of a small amount has a sufficient effect, it leads to cost reduction. Naturally, it is not necessary to treat the molded product with a fluorine coat or the like, which leads to omission of the process. In addition, since it has high water repellency, it has the effect of suppressing intrusion of moisture from the molded product surface and delaying hydrolysis of the polyester resin even under high temperature and high humidity, and the gloss of the molded product surface even under such severe conditions Is maintained, and mechanical properties are also maintained. From the above viewpoint, the fluorinated alkyl ester polymer (C) is an essential component in the present invention. The amount of the fluorinated alkyl ester polymer (C) is 0.01 to 10% by weight, preferably 0.1 to 5% by weight, based on the whole composition. If it is too small, the effect of lowering the surface free energy is so small that a sufficient toner adhesion preventing effect cannot be obtained. If it is too large, the mechanical properties may be reduced.

The resin material used in the present invention may optionally contain a filler. Such a filler is preferably blended in order to obtain excellent properties such as mechanical strength, heat resistance, dimensional stability, and electrical properties, and is particularly effective for increasing rigidity. For this purpose, a fibrous, powdery or plate-like filler is used depending on the purpose.

Examples of the fibrous filler include glass fiber, asbestos fiber, carbon fiber, silica fiber, silica / alumina fiber, zirconia fiber, boron nitride fiber, silicon nitride fiber, boron fiber, potassium titanate fiber, stainless steel, aluminum And metal fibrous materials such as titanium, copper, and brass. In addition, a high melting point organic fibrous substance such as polyamide, fluororesin, and acrylic resin can also be used.

Examples of the particulate filler include carbon black, quartz powder, glass beads, glass powder, silicates such as calcium silicate, aluminum silicate, kaolin, talc, clay, diatomaceous earth, and wollastonite, and oxides. Iron, titanium oxide, oxides of metals such as alumina, calcium carbonate,
Examples thereof include metal carbonates such as magnesium carbonate, metal sulfates such as calcium sulfate and barium sulfate, silicon carbide, silicon nitride, boron nitride, and various metal powders.

As the plate-like inorganic filler, mica,
Examples include glass flakes and various metal foils.

The type of the filler is not particularly limited, and one or more fillers may be added. Particularly, potassium titanate fiber, mica, talc, and wollastonite are preferably used.

The filler is desirably added to 50% by weight or less, more preferably 30% by weight or less of the whole composition. When the filler is added in excess, the moldability is poor and the toughness is reduced.

In the resin composition of the present invention, other thermoplastic resins may be used in a small amount in addition to the above components, depending on the purpose. For example, polyamide, polycarbonate, polyphenylene sulfide, polyphenylene oxide, polyacetal, polysulfone,
Examples include polyethersulfone, polyetherimide, polyetherketone, and fluorine resin. In addition, a styrene-based copolymer such as acrylonitrile-styrene or acrylonitrile-butadiene-styrene, or a rubber-modified styrene-based copolymer can be used in combination for the purpose of improving toughness and low warpage.

However, in order not to impair the properties of the polyester resin, it is necessary that the blending amount of these thermoplastic resins does not exceed 50% by volume in the resin component. If the volume fraction exceeds 50%, the sea component of the sea-island structure in the polymer alloy will not be a polyester resin, and the properties of the polyester resin will be impaired.

Further, in the resin composition used in the present invention, a known substance generally added to a thermoplastic resin or the like can be added and used in order to impart desired properties according to the purpose. For example, stabilizers such as antioxidants, ultraviolet absorbers, and light stabilizers, antistatic agents, lubricants, release agents, coloring agents such as dyes and pigments, and plasticizers can be added. In particular, the addition of an antioxidant for improving heat resistance is effective.

The polyester resin composition of the present invention can be easily prepared by equipment and methods generally used as conventional resin composition preparation methods. For example, (1) a predetermined amount of components constituting the composition of the present invention are mixed at once and melt-kneaded by a single-screw or twin-screw extruder to obtain pellets of a desired composition. (2) With a single-screw or twin-screw extruder having two or more raw material input ports, a resin, a stabilizer, a pigment component, and the like are charged from the first input port and melt-kneaded, and then the second raw material input port is provided. For example, an inorganic filler is added, and the mixture is melt-kneaded to obtain a pellet having a desired composition.

The method for molding the resin composition of the present invention is not particularly limited, such as injection molding, extrusion molding, blow molding, etc., but injection molding is particularly preferred.

The obtained molded product is guided to a transfer unit such as paper or polyester film for transferring an electrostatic latent image from a photosensitive drum to a transfer unit in an electronic printing apparatus such as a printer, a copying machine, a facsimile, and the like. Guide to the fixing section,
Also suitable for OA parts such as a transfer member guide member that is installed at a predetermined position in order to carry the toner out of the fixing unit, such as a member that may cause image disturbance on the transfer member due to toner adhesion. It is.

[0037]

EXAMPLES The present invention will now be described specifically with reference to examples, but the present invention is not limited to these examples. Examples 1 to 7 and Comparative Examples 1 to 7 After mixing the components at the ratios shown in Table 1, the mixture was melt-kneaded by a twin-screw extruder to prepare a pellet-shaped composition. Next, a test piece was prepared from the pellet by injection molding and evaluated.

Further, for comparison, as shown in Table 2, evaluation was also made of a sample without the fluorinated alkyl ester polymer and a sample with the addition of polytetrafluoroethylene.

The evaluation items and evaluation methods are as follows. Flammability; 150mm x 6mm x 3mm rod-shaped test pieces were prepared.
The oxygen index was measured according to JIS K7201. The larger the oxygen index is, the higher the flame retardancy is. Contact angle: Using a screw-type injection molding machine, a 30 mm x 50 mm x 3 mm plate is formed at a cylinder temperature of 250 ° C and a mold temperature of 70 ° C, and droplets (water, ethanol, hexane) are formed on the plate.
Dropping was performed, and the angle formed by a tangent drawn from the contact point between the droplet on the surface of the plate and the plate and the surface of the droplet, that is, the contact angle (θ) was measured. After wiping with ethanol so as not to damage the plate surface, Kyowa Interface Science Co., Ltd. contact angle measuring instrument FACE CA-Z
Was measured at room temperature and 25 ° C. If the contact angle is large, it indicates that the surface energy of the molded article is low and the effect of preventing toner adhesion is high.

The details of each component used in the examples are as follows. -Flame retardant A: Brominated epoxy compound-Flame retardant B: Ethylene bistetrabromophthalimide-Flame retardant auxiliary agent: Antimony trioxide-Fluorinated alkyl ester polymer; -1 ・ Polytetrafluoroethylene; manufactured by Hoechst, trade name Hostaflon TF1620

[0041]

[Table 1]

[0042]

[Table 2]

In Comparative Examples 1 to 5, the liquid spread on the surface of the molded article immediately after dropping, and the contact angle of ethanol could not be measured.

[0044]

As described above, in the molded article made of the polyester resin composition of the present invention, the free energy of the molded article surface is reduced by adding and blending the fluorinated alkyl ester polymer, and the water repellency and water repellency are reduced. It has oil hardening and is provided with an antifouling property so that an effect of preventing toner adhesion can be obtained,
It is suitably used for parts in an OA apparatus such as a printer, a copying machine, and a facsimile where toner adhesion is a problem.

Claims (5)

[Claims] (B) 1 to 30% by weight of a flame retardant (in the whole composition) (C) 0.01 to 10% by weight of a fluorinated alkyl ester polymer based on (A) a polyester resin
A polyester resin composition for OA parts, wherein (in all compositions) is added and blended. 2. The polyester resin composition for OA parts according to claim 1, wherein (A) the polyester resin is polybutylene terephthalate, polyethylene terephthalate or a mixture thereof. (C) The fluorinated alkyl ester polymer is
2. A perfluoroalkyl group-containing oligomer.
Or the polyester resin composition for OA parts according to 2. 4. A molded part for OA, which is molded from the polyester resin composition according to any one of claims 1 to 3, and has excellent anti-toner properties. 5. The molded part according to claim 4, which is used for a printer, a copier or a facsimile.