JP3272832B2 - Polishing monofilament - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polishing monofilament. More specifically, the present invention relates to a polishing monofilament which is excellent in abrasiveness and durability and is suitable for uses such as industrial brushes.

[0002]

2. Description of the Related Art In the field of polishing and grinding materials such as industrial brushes, it is well known to use a polishing monofilament made of a thermoplastic resin containing an abrasive. Nylon 6 resin, nylon 6 as thermoplastic resin
10 resin, nylon 612 resin and the like (for example, Japanese Patent Application Laid-Open No. 4-41183, Japanese Patent Publication No. 3-263).
No. 2, JP-B-62-14645 ). However, the durability has not yet reached a sufficient level.

Various methods have been proposed for improving the durability of the polishing monofilament. Specifically, a method of blending polybutylene terephthalate with an ester elastomer having excellent flexibility to improve durability (for example, Japanese Patent Application Laid-Open No. 60-252715 ), a method of preparing a high-viscosity nylon 6 Nylon 6/66 copolymer (for example, Japanese Patent Publication No. 63-791)
No. 1), a method using a nylon 12 resin (for example,
JP-A-62-39184). However, these methods do not show significant improvement in durability, and reduce the grindability, which is the purpose of the polishing monofilament. The characteristics required for the polishing monofilament are high grinding properties and durability, and no current polishing monofilament has both properties.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a polishing monofilament excellent in durability and grindability.

[0005]

Means for Solving the Problems The present inventors diligently study whether a polishing monofilament having high durability and grindability can be found, and greatly improve the durability and grindability by performing a specific combination of nylon resin. And found the present invention based on this finding. That is, the present invention
A monofilament comprising a nylon resin and abrasive particles having a particle size of # 30 to # 3000, wherein the nylon resin has a relative viscosity of 3.0 or more;
The resin contains at least one resin selected from two resins and a nylon 12 resin having a relative viscosity of 3.0 or more, the ratio thereof is 20:80 to 80:20, and the ratio of abrasive particles in the monofilament is The present invention relates to a polishing monofilament characterized in that the content is 5 to 50% by weight.

[0006] The relative viscosity of the nylon resin used in the present invention is 3.0 or more. If it is less than 3.0, the thickness may fluctuate or the yarn may break immediately under the spinning during melt spinning, which is not preferable. Although the upper limit of the relative viscosity is not particularly defined, it is preferably 6.0 or less from the viewpoint of spinnability. When the relative viscosity exceeds 6.0, the viscosity of the melt is remarkably increased and spinning becomes difficult. It is desirable that the difference in relative viscosity between nylon resins is small in consideration of kneading properties, but there is no problem in spinnability, durability and grinding properties.

The relative viscosity referred to in the present invention is a value obtained by measuring the viscosity of a solution obtained by dissolving 1 g of a thermoplastic resin in 100 ml of 98% by weight concentrated sulfuric acid at 25 ° C. using an Ostwald viscometer. In the present invention, in order to achieve the durability and grindability in the present invention, the weight ratio of at least one resin selected from nylon 610 resin and nylon 612 resin to nylon 12 resin in the nylon resin is 20:80 to 80. : 20 is important.

In the present invention, it is possible to add another nylon resin (eg, a copolymer resin of nylon 66 and nylon 6, a nylon 66 resin) other than the above nylon resin to improve the spinnability. Na in resin
Iron 12 resin , nylon 610 resin, nylon 612
The total amount of the resin is desirably 90% or more of the nylon resin.

The abrasive particles usable in the present invention include oxides such as aluminum oxide and zirconium oxide, carbides such as silicon carbide, nitrides such as silicon nitride, and artificial abrasives such as artificial diamond or diamond, corundum and emery. And natural abrasives such as garnet. These may be used alone or in combination of two or more. The particle size of the abrasive particles is usually in the range of # 30 to # 3000, but those having the range of # 46 to # 2000 can be preferably used from the viewpoints of abrasiveness, grinding power and spinnability. In addition,
The particle size of the abrasive particles of the present invention conforms to JIS R6001.

The content of the abrasive particles in the polishing monofilament in the present invention is in the range of 5% by weight to 50% by weight of the thermoplastic resin, particularly preferably in the range of 10% by weight to 40% by weight. If it is less than 5% by weight, the polishing properties and grinding power are insufficient, and if it exceeds 50% by weight, it is not preferable because the forming of the monofilament becomes extremely difficult and the durability is greatly reduced.

The abrasive particles in the present invention are not only effective as abrasives. Nylon 1 without abrasive particles
Monofilament spinning at any ratio was not possible with a blend of 2 resin and nylon 610 resin. However, the addition of the abrasive particles enabled the monofilament to be spun at an arbitrary ratio, thereby making it possible to clarify the effects of the present invention.

In order to enhance the adhesiveness between the abrasive particles and the thermoplastic resin, there are two types of functional groups: a silane coupling agent (a methoxysilane group or the like chemically bonded to an inorganic material, and a functional group having good adhesiveness to an organic material). ) Can be similarly used in the present invention as is usually used for nylon 6 resin, nylon 12 resin, and nylon 610 resin.
The polishing monofilament of the present invention is obtained by blending an abrasive with nylon resin pellets, mixing the mixture uniformly, melting the mixture with a melt extruder, spinning the same out into a cooling water through a spout hole, and subsequently stretching. Here, the cross-sectional shape of the polishing monofilament is generally circular, but may be elliptical or rectangular as required.

The average thread diameter of the polishing monofilament of the present invention is usually in the range of 0.3 mm to 2.5 mm.
Those having a size of 6 mm to 1.6 mm are often used.

[0014]

Next, the present invention will be described in more detail with reference to examples. The durability was evaluated by the following method. Durability: A total of 30 polishing monofilaments are fixed to a cylindrical roll having a diameter of 23 cm on a circumferential surface so as to be radial from the center, and this roll is rotated at 1200 rpm to obtain a steel plate gradually pushed up from below. The durability is expressed by the time (minutes) until the surface of the polishing monofilament starts to be broken due to bending fatigue by colliding with the surface. Here, the length from the roll-side fixed position of the polishing monofilament to the tip of the steel plate side is 30 mm, and the distance from the roll-side fixed position of the polishing monofilament to the steel plate surface is 20 mm. The polishing monofilament under evaluation was sprayed with hot water of 45 ° C. at 150 L / Hr according to the actual use.
It is always spraying on.

Grindability: A total of 320 polishing monofilaments are fixed on a cylindrical roll having a diameter of 23 cm so as to be radial from the center on the circumferential surface.
Rotate at 0 rpm, colliding with the surface of the copper plate gradually pushed up from below, measure the weight loss of the copper plate over a certain period of time.
Less than △ and 5 g or more were ○. Here, the length from the roll-side fixing position of the polishing monofilament to the tip of the copper plate side is 30 mm, and the distance from the roll-side fixing position of the polishing monofilament to the copper plate surface is 20 mm. The number of polishing monofilaments under evaluation is always 4
Spray hot water of 5 ° C shall be sprayed at 150 L / Hr. In addition, since the abrasive material of the polishing monofilament before use is often not exposed on the surface, it is the same as a copper plate for 1 minute with a sandpaper (# 240) and subsequently for 10 minutes with an iron plate before evaluating the grindability. Contact by way. Thereafter, the copper plate is ground for 45 minutes, and the amount obtained by grinding the copper plate is measured and defined as the grinding amount. Here, the copper plate was larger than the area to be ground, and had a thickness of 2 mm and a weight of 780 g.

[0016]

Example 1 45 kg of pellets of nylon 12 resin having a relative viscosity of 3.5, 15 kg of pellets of nylon 610 resin having a relative viscosity of 3.3, and 25 wt% of # 10 with respect to both resins
Of silicon carbide (manufactured by Showa Denko KK) and 0.4% by weight of a silane coupling agent (KBM-603, manufactured by Shin-Etsu Chemical Co., Ltd.) based on silicon carbide, and uniformly mixed with a 150 L tumbler mixer. Mixed. Next, the mixture was put into a hopper provided at the upper part of the melt extruder, introduced into a melting zone of a single screw extruder kept at 270 ° C. and melted, and 20 m / min from a spout having a hole diameter of 2.8 mm. It was spun into cooling water at room temperature at a speed. Subsequently, the solidified monofilament was wound up at a rate of 50 m / min while being stretched 2.6 times in a gas stretching bath at 280 ° C. to obtain a polishing monofilament having a yarn diameter of 1.6 mm. Table 1 shows the durability and grindability of this polishing monofilament.

[0017]

Example 2 A polishing monofilament having a yarn diameter of 1.6 mm was obtained in the same manner as in Example 1, except that the ratio of nylon 12 resin to nylon 610 resin was 50:50. Table 1 shows the durability and grindability of this monofilament.

[0018]

Example 3 A polishing monofilament having a yarn diameter of 1.6 mm was obtained in the same manner as in Example 1, except that the ratio of nylon 12 resin to nylon 610 resin was 25:75. Table 1 shows the durability and grindability of this monofilament.

[0019]

Example 4 A monofilament for polishing having a yarn diameter of 1.6 mm in the same manner as in Example 1 except that the ratio of nylon 12 resin to nylon 612 resin having a relative viscosity of 3.3 was 75:25. I got Table 1 shows the durability and grindability of this monofilament.

[0020]

Example 5 Nylon 12 resin 75% by weight, nylon 6
15% by weight of 10 resin and 10% by weight of nylon 612 resin
Was obtained in the same manner as in Example 1 to obtain a polishing monofilament having a yarn diameter of 1.6 mm. Table 1 shows the durability and grindability of this monofilament.

[0021]

Comparative Example 1 A polishing monofilament having a yarn diameter of 1.6 mm was obtained in the same manner as in Example 1 using 100% nylon 12 resin pellets. Table 1 shows the durability and grindability of this monofilament.

[0022]

Comparative Example 2 A polishing monofilament having a yarn diameter of 1.6 mm was obtained in the same manner as in Example 1 using 100% nylon 610 resin pellets. The durability of this monofilament,
Table 1 shows the grindability.

[0023]

Comparative Example 3 A polishing monofilament having a yarn diameter of 1.6 mm was obtained in the same manner as in Example 1 using 100% nylon 612 resin pellets. The durability of this monofilament,
Table 1 shows the grindability.

[0024]

Comparative Example 4 Spinning was carried out in the same manner as in Example 1 except that the ratio of nylon 12 resin to nylon 610 resin was 75:25 and abrasive particles and a coupling agent were not added. However, the monofilament could not be obtained.

[0025]

Comparative Example 5 When the ratio of nylon 12 resin to nylon 610 resin was set to 75:25, a coupling agent was added, and spinning was performed in the same manner as in Example 1 without adding abrasive particles. And the polymer was not connected, and a monofilament could not be obtained.

[0026]

Comparative Example 6 A polishing monofilament having a yarn diameter of 1.6 mm was obtained in the same manner as in Example 1 using 100% nylon 6 resin pellets. Table 1 shows the durability and grindability of this monofilament.

[0027]

Comparative Example 7 A copolymer resin of nylon 6 and nylon 66 (the ratio of nylon 6 component to nylon 66 component was 85: 1)
A polishing monofilament having a yarn diameter of 1.6 mm was obtained in the same manner as in Example 1 using the pellets of 5). Table 1 shows the durability and grindability of this monofilament.

As is clear from Table 1, while there has been no polishing monofilament having both durability and grindability up to now, the polishing monofilament of the present invention has high grindability while maintaining high grindability. It is clear that the durability has been greatly improved.

[0029]

[Table 1]

[0030]

As described above, the polishing monofilament of the present invention has very high durability while maintaining high grindability as compared with the conventional polishing monofilament. Therefore, when applied to an industrial brush, high grindability and excellent durability for maintaining this grindability are obtained, and high polishing and grinding effects can be exhibited.

Continuation of the front page (56) References JP-A-62-39184 (JP, A) JP-A-61-125777 (JP, A) JP-A-60-252715 (JP, A) JP-A-4-41183 (JP) JP-A-53-5490 (JP, A) JP-B-3-2632 (JP, B2) JP-B-63-7911 (JP, B1) (58) Fields investigated (Int. Cl. ⁷ , DB Name) D01F 6/90

Claims (1)

(57) [Claims] 1. A nylon resin having a particle size of # 30 to # 300.
Monofilament comprising abrasive particles having a relative viscosity of at least one resin selected from the group consisting of nylon 610 resin having a relative viscosity of 3.0 or more and nylon 612 resin, and nylon 12 resin having a relative viscosity of 3.0 or more. A monofilament for polishing, characterized in that the monofilament is contained in a ratio of 20:80 to 80:20 and the ratio of abrasive particles in the monofilament is 5 to 50% by weight.