JPS61290464A - Stripping claw for fixing - Google Patents

Abstract

PURPOSE:To improve toner sticking preventiveness and to prevent the malfunction of a machine by the discharge of static electricity by adding a carbonaceous conductivity applying agent to a compsn. prepd. by using a thermoplastic polyether arom. ketone as a base material and compounding heat resistant reinforcing fibers, inorg. filler, etc. therewith. CONSTITUTION:The titled stripping claw is obtd. by injection molding of the compd. consisting of 95-40pts. (by weight) thermoplastic polyether arom. ketone (PEEK), 5-60pts. heat resistant reinforcing fibers such as potassium titanate fibers, asbestos fibers or arom. polyamide fibers, 0-40pts. filler such as talc and 3-20pts. conductivity applying agent such as ketine black or acetylene black. The stripping claw for fixing consisting of such PEEK as the matrix has the excellent sharpness of a blade edge, heat resistance, impact resistance, non-attack characteristic to a roll surface, moisture resistance, etc. and therefore the durability and shape stability of the blade edge are improved. The electric conductivity is provided thereto and the static electricity is removed therefrom. There is no sticking and solidifying of a toner even if the blade edge is coated with 'Teflon(R)'. In addition, the malfunction of the circuit by the discharge is prevented and this stripping claw is used for a copying machine, printer, printing machine, etc.

Description

Detailed Description of the Invention (a) Industrial Application Field The present invention relates to a peeling claw for a fixing roll of a copying machine, a printer, a printing machine, etc. (hereinafter referred to as a fixing peeling claw) Peek-based claws with excellent peeling performance, that is, excellent sharpness of the cutting edge, heat resistance, impact resistance, non-aggressiveness to the fixing roll, etc., and good shape stability of the cutting edge. Furthermore, by imparting electrical conductivity, this was done to improve functions such as preventing toner from sticking due to static electricity and preventing machine malfunctions due to electrostatic discharge.

(b) Conventional technology Peeling nails for fixing have been put into practical use using heat-resistant resins such as polyamideimide, polyimide, and polyphenylene sulfide as base materials, but polyimide and polyphenylene sulfide have poor impact resistance. Generally, polyamide-imide claws were used because the cutting edge is easily damaged and has heat resistance and toughness. It easily absorbs moisture during storage, transportation, suspension of use, etc., and once it absorbs moisture, the blade edge may become deformed at relatively low temperatures, gas bulges may occur at the contact area of the blade edge with the fixing roll, and this may result in poor peeling. There were drawbacks such as.

The inventors of the present invention, compared to the conventional barring nails as described above,
The invention was based on a PEEK-based claw that has many advantages such as sharpness of the cutting edge, heat resistance of the cutting edge, and non-deformability of the cutting edge due to moisture absorption. Used in many models.

Additionally, in general, resin peeling claws promote the adhesion of molten toner to the cutting edge due to the static electricity generated by the friction of the paper during fusing, as well as the static electricity held by the toner itself, and when this accumulates and solidifies, the fluororesin-coated roll is removed. Thoughts arise that scratch the surface. Therefore, in order to prevent this, it is common practice to coat the cutting edge of the claw with a fluororesin or a fluororesin containing a filler, or to supply a large amount of lubricating oil.

However, coating the cutting edge with fluororesin increases the cost considerably, and supplying a large amount of lubricating oil stains the paper. Both methods have disadvantages.

Although prevention of toner adhesion can be ensured even with such measures, it has been observed that electrostatic discharge causes circuit noise and malfunction, and there has been a demand for improvement.

(c) Problems to be solved by the invention Prevention of toner adhesion occurring on the exposed claw portion as described above;
In order to prevent machine malfunctions due to static electricity discharge, the present inventors have conducted extensive research with the aim of adding conductivity to a PEEK resin matrix while retaining the excellent functionality of the claw. As a result, this invention was completed.

In the present invention, we have completed a molding composition that can be molded by adding and kneading the above-mentioned conductive agent in an amount that imparts the required conductivity without impairing the properties of the wire. It is something.

(d) Means for Solving the Problems As a result of experiments, the inventor of the present invention has found that by adding an appropriate amount of carbon-based conductivity imparting agents such as Ketjen black and acetylene black, the characteristics of copy paper, which is a feature of PEEK-made pruning nails, can be improved. This is a completed claw with excellent electrical conductivity without impairing releasability, sharpness of the cutting edge, heat resistance, impact resistance, non-aggressiveness to the fixing roll, shape stability of the cutting edge, etc.

To remove static electricity, a volume resistivity value of 10Ω or less is required, but the amount of conductivity imparting agent required for this is determined by Imaichi 1.
The amount of Ketjen black is 3 to 10 parts, and the amount of acetylene black is 8 to 20 parts based on ioo parts.

(e) Effect The present invention is based on a composition in which PEEK (thermoplastic polyether aromatic ketone) is used as a base material, and heat-resistant reinforcing fiber alone or partially substituted with an inorganic filler, and a carbonaceous conductivity imparting agent is further added to the composition. By blending in an appropriate amount, toner adhesion prevention properties can be improved and machine malfunctions caused by static electricity discharge can also be prevented.

(f) Examples Examples according to the present invention will be described below in comparison with conventional examples (reference examples).

Reference example PEEK (VI CTREX, 450 manufactured by ICI)
P) 70 parts (weight ratio) Potassium titanate fiber (Tismo manufactured by Ohita Chemical Co., Ltd. 30 parts (〃) Length 20μ
, diameter 0.5μ) in a mixer, kneaded into pellets using a single screw extruder, and further used this pellet to form a claw by injection molding. A comparative test was conducted.

The volume resistivity measured for this reference example was 10'3Ω or more.

Example (1) PEEK (same as the reference example e) 60 parts Potassium titanate fiber (〃 ) 3o〃Ketsutien blank (manufactured by Kao Akzo Co., Ltd.) 1o〃 was blended, and a nail was formed in the same manner as the reference example. did.

The volume resistivity was 100, and excellent electrical conductivity was obtained.

In addition, other properties as a claw (patent application No. 14 of 1982)
No. 9859) was also comparable to the reference example.

Example (2) PEEK (same as reference example) 50 parts Potassium titanate fiber (〃 ) 30 parts Ketjenblack (same as Example 1) 5〃Talc
15〃It was molded in the same manner as in Example 1, and the volume resistivity was 106Ω as a result of measurement.

Example (3) PEEK (same as the previous example) 50 parts titanium potash fiber (〃 ) 30〃Acetylene black (manufactured by Denki Kagaku Co., Ltd.) 15# Talc
55 was molded in the same manner as the previous two examples, and the volume resistivity was measured to be 10''Ω.

All of the examples had good moldability, imparted electrical conductivity, and did not impair other properties as a nail.

(g) Effects of the Invention As mentioned above, the peeling claw for fixing rolls using PEEK resin as a matrix according to the present invention has excellent cutting edge sharpness, heat resistance, impact resistance, non-aggressiveness to the roll surface, and Not only does it provide durability and shape stability to the blade edge due to its moisture resistance, but it also succeeds in imparting conductivity, which eliminates static electricity and prevents toner from adhering and hardening without the need for a Teflon coating on the blade edge. Moreover, it is possible to prevent circuit malfunctions due to discharge, and it has great industrial effects, such as being useful in reducing manufacturing costs.

Patent Applicant: Starlight Industries Co., Ltd. Procedural Amendment (Jibutsu July 4, 1985 2, Peeling Claw 3 for Fixing the Name of the Invention, Relationship with the Person Who Makes the Amendment Case) Patent Applicant

Claims (1)

[Claims] In terms of weight ratio, (a) thermoplastic polyether aromatic ketone (hereinafter referred to as PEE)
K) 95 to 40 parts (b) Heat-resistant reinforcing fibers such as potassium titanate fibers, asbestos fibers, aromatic polyamide fibers, etc. 5 to 60 parts (c) Fillers such as talc 0 to 40 parts (d) K. A peeling claw for fixing rolls of copying machines, printers, printing machines, etc., which is injection molded with 3 to 20 parts of a conductivity imparting agent such as chain black or acetylene black.