CN111015536B

CN111015536B - Sand planting method and production system of coated abrasive tool

Info

Publication number: CN111015536B
Application number: CN201911304288.0A
Authority: CN
Inventors: 金成炫; 安坤华; 魏艳阳; 刘富阳; 安亚伦
Original assignee: White Dove Abrasives Co ltd
Current assignee: White Dove Abrasives Co ltd
Priority date: 2019-12-17
Filing date: 2019-12-17
Publication date: 2021-06-29
Anticipated expiration: 2039-12-17
Also published as: CN111015536A

Abstract

The invention relates to a sand planting method and a production system of a coated abrasive tool. The sand planting method of the coated abrasive tool comprises the following steps: before the abrasive is dried after being adsorbed to the base material, a non-mechanical external force is applied to the abrasive to arrange a part of the abrasive obliquely with respect to the surface of the base material. The sand planting method of the coated abrasive tool provided by the invention changes the sand planting angle of one part of the grinding materials through non-mechanical external force, the grinding materials which are obliquely arranged on the part have better sharpness during grinding, and experiments prove that the grinding performance and the processing efficiency of the coated abrasive tool product can be improved to a certain extent.

Description

Sand planting method and production system of coated abrasive tool

Technical Field

The invention belongs to the field of coated abrasive tools, and particularly relates to a sand planting method and a production system of a coated abrasive tool.

Background

Coated abrasives are known as flexible abrasives which are attached to a flexible substrate by a binder. The sand planting is an important link for preparing the coated abrasive tool, and the traditional sand planting mode comprises gravity sand planting and electrostatic sand planting. The gravity sand planting is that the sand is planted under the gravity action of the grinding material, and the sand planting direction of the grinding material has randomness. At present, the application of electrostatic sand planting is more and more extensive, and it can obtain comparatively unanimous abrasive material arrangement effect, and its working process utilizes the high voltage electrostatic field that external power source provided, relies on the electrical property of abrasive material when the abrasive material is marchd, makes the abrasive material become electrified body, produces directional (generally the thick head is towards the substrate direction, and the thin head is opposite) jump and is adsorbed on the substrate that has the binder.

Chinese patent publication No. CN102124070B discloses a coated abrasive article and a method for making and using the same, wherein the coated abrasive article comprises a fabric backing and an abrasive layer disposed on the fabric backing, the abrasive layer comprises a make coat, an abrasive is embedded in the make coat, and a size coat covers the make coat and the abrasive. In the existing coated abrasive tool, based on the working process of electrostatic sand-planting, the sand-planting angle between the abrasive material and the base material (the angle between the connecting line of the thick head central point and the thin head central point of the abrasive material and the base material) is usually maintained at 90 degrees, and during grinding, the contact angle between the workpiece to be processed and the coated abrasive tool is usually maintained at 90 degrees, so as to exert the maximum grinding service life and the maximum grinding efficiency of the abrasive tool product. The grinding performance of the existing coated abrasive tools is still to be improved.

Disclosure of Invention

The invention aims to provide a sand planting method of a coated abrasive tool, which aims to solve the problem that the grinding performance of the existing coated abrasive tool needs to be improved.

A second object of the present invention is a production system for the above-described method for producing a coated abrasive.

In order to achieve the purpose, the technical scheme of the sand planting method of the coated abrasive tool is as follows:

a sand planting method of a coated abrasive tool comprises the following steps: before the abrasive is dried after being adsorbed to the base material, a non-mechanical external force is applied to the abrasive to arrange a part of the abrasive obliquely with respect to the surface of the base material.

The sand planting method of the coated abrasive tool provided by the invention changes the sand planting angle of one part of the grinding materials through non-mechanical external force, the grinding materials which are obliquely arranged on the part have better sharpness during grinding, and experiments prove that the grinding performance and the processing efficiency of the coated abrasive tool product can be improved to a certain extent.

The non-mechanical external force is the external force which is not directly in mechanical contact with the abrasive, and the mechanical contact operation is carried out by poking, pressing and the like if an object is used; the non-mechanical external force can avoid damage to the abrasive caused by mechanical contact, so that the external force for inclining the abrasive is not large generally, fine control is realized conveniently through the non-mechanical external force, the method has more advantages in the aspect of industrial implementation, and the stability of the product can be improved. Non-mechanical external forces such as wind, electric, magnetic, etc. In view of simplicity and reliability of industrial implementation, it is preferable that the non-mechanical external force is wind force.

In order to further improve the effectiveness of changing the sand planting angle of the abrasive by the wind power, the force application position of the wind power is preferably located at the turning position of the base material when the base material travels before the abrasive is dried after being adsorbed to the base material. In order to conveniently change the sand planting angle of the abrasive, the force application direction of the wind force is preferably opposite to the advancing direction of the base material.

It will be readily appreciated that the wind force may be provided by a wind blowing device or a wind suction device. Preferably, the blowing air forms an impact air curtain with a width not less than the width of the base material, and the abrasive is blown obliquely downwards.

In order to achieve a good adjustment effect on the sand planting angle and optimize the grinding performance of the abrasive belt, preferably, the pressure of the wind power is 40-180PSI, the wind power is provided by a blowing device, the height of a blowing opening of the blowing device from a base material is 5-20cm, the angle between the blowing direction and the base material is 90-150 degrees, and the advancing speed of the base material is 10-40 m/min.

The method is characterized in that a working procedure of changing the sand planting angle by non-mechanical external force is added in the production flow of the existing coated abrasive tool, and other working procedures and related raw materials are the same as those in the prior art. The related raw materials are briefly described below.

The substrate can be selected from polyester cloth, cotton cloth, blended cloth of chemical fiber and cotton, polyester film, paper substrate, etc. The thickness range of the polyester cloth base material can be different from 0.3mm to 0.7 mm. The thickness of cotton cloth can be 30 μm to 250 μm. The basis weight of the paper substrate can be from 30 to 500 grams per square meter.

The abrasive can be selected from zirconia corundum, ceramic corundum, etc. The abrasive may have a particle size of 5-1400 μm. The larger the grain size of the abrasive, the better the effect of changing the sand planting angle by the blowing method of the invention is, and the more preferably 300-1400 μm.

The selection of the primer solution and the size compounding solution is not particularly limited. The glue solution variety of the existing coated abrasive tool can meet the use requirement. The coating thickness of the primer solution and the laminating solution can also refer to the related prior art. Taking the primer solution as an example, the larger the grain size of the abrasive, the larger the required coating thickness of the primer solution is, and the coating thickness of the primer solution is generally 20% -40% of the grain size of the abrasive.

The primer solution can comprise the following raw materials in parts by weight: 30-60 parts of binder, 20-40 parts of filler, 1-2 parts of defoaming agent, 1-2 parts of surfactant, 1-2 parts of thickener and 1 part of pigment.

The complex glue solution can comprise the following raw materials in parts by weight: 30-60 parts of binder, 20-40 parts of filler, 1-2 parts of defoaming agent, 1-2 parts of surfactant, 1-2 parts of thickener and 1 part of pigment.

According to the specific application occasion of the coated abrasive tool, the super-coating glue solution can be further coated after the compound glue solution is dried, and the super-coating glue solution can comprise the following raw materials in parts by weight: 20-40 parts of binder, 40-60 parts of filler, 1-2 parts of defoaming agent and 1-2 parts of surfactant. Coated abrasive articles with a supercoat are more advantageous in terms of heat dissipation, lubrication, and other functions.

The method has no special requirement on the sand planting density of the abrasive, and generally speaking, the sand planting density of the coated abrasive product with the sand planting density of 300-1800 grams per square meter can meet the requirement.

In order to further optimize the processing efficiency of the coated abrasive product, the inclined arranged abrasive material has a sand planting angle alpha of 30 degrees to alpha less than 90 degrees, and the abrasive material with the sand planting angle alpha of 30 degrees to alpha less than 90 degrees accounts for 20-50 percent of all the abrasive material. At present, abrasive belt grinding is mostly manual processing, different operating personnel's operation gimmick is different, for guaranteeing the commonality of product, makes partly abrasive material normally upright plant sand, and partly abrasive material slope, when using in the initial stage, upright abrasive material possesses stronger cutting force, uses the later stage in the abrasive belt, especially when the abrasive belt is used in reverse, makes the work piece of processing be greater than 90 degrees angle contacts with slope abrasive material, keeps the stronger cutting force in abrasive belt.

The technical scheme of the coated abrasive tool production system is as follows:

a coated abrasive production system comprises a primer coating device, a coating device and a control device, wherein the primer coating device is used for coating a primer solution on a base material; the electrostatic sand planting equipment is used for implanting abrasive materials on the base material coated with the primer; the compound glue coating equipment is used for coating compound glue solution; the glue solution curing equipment is used for curing the glue solution on the base material; further comprising:

the force application equipment is arranged at the downstream of the electrostatic sand planting equipment; a non-mechanical external force is applied to the abrasive to cause a portion of the abrasive to be obliquely disposed relative to the substrate surface.

According to the coated abrasive tool production system provided by the invention, the sand planting angle of the abrasive material is changed by additionally arranging the force application equipment, the process is simple, the application range is wide, the sand planting angle of the abrasive material can be conveniently adjusted, and a coated abrasive tool product with a certain proportion of inclined abrasive material is prepared.

In order to improve the adaptability in industrial production, the force application device is preferably a wind power device. The wind power equipment forms certain wind pressure through blowing or suction so as to change the sand planting angle of the grinding material.

Further, the wind power equipment is gas injection equipment, the gas injection equipment is provided with an injection opening, gas is injected from the injection opening, and air pressure is applied to the implanted abrasive on the base material, so that the sand planting angle of the abrasive is changed. The blowing equipment has lower requirements on the production environment and has more advantages in the aspect of production suitability.

In order to improve the uniformity of the air blowing pressure, it is preferable that the air blowing port is a slit having a length extending in the width direction of the substrate.

In order to improve the operation efficiency of changing the sand planting angle of the abrasive, the force application position of the wind power device on the base material is preferably located at the turning position when the base material travels.

Drawings

FIG. 1 is a schematic view of a coated abrasive production system of the present invention;

FIG. 2 is a schematic representation of the abrasive morphology of a prior art coated abrasive tool;

FIG. 3 is a schematic view of the abrasive morphology of a coated abrasive article made according to the present invention;

FIG. 4 is a schematic diagram comparing a prior art vertical abrasive to the angled abrasive of the present invention in grinding a workpiece;

FIG. 5 is a schematic view of a substrate after passing over rollers in the prior art;

FIG. 6 is an enlarged view of the dashed box portion of FIG. 1;

FIG. 7 is a graph of total cut and SGE for examples 2 to 4 and comparative example;

FIG. 8 is a graph of total cut and SGE for examples 5 to 8 and comparative example;

FIG. 9 is a graph of total cut and SGE for examples 9-12 and comparative examples;

FIG. 10 is a graph of total cut and SGE for examples 13 to 20 and comparative example;

the method comprises the following steps of 1-base material uncoiling machine, 2-glue spreader, 3-grinding bin, 4-grinding material conveyor belt, 5-electrostatic sand-planting machine, 6-air knife, 7-drying furnace, 8-base material, 80-vertical grinding material, 81-inclined grinding material, 9-roller, 10-grinding material, 11-bottom glue layer, 12-compound glue layer, 13-super coating and 14-workpiece.

Detailed Description

The following further describes embodiments of the present invention with reference to the drawings.

First, an embodiment of the coated abrasive production system of the present invention

Example 1

The coated abrasive production system of the embodiment, as shown in fig. 1, includes a substrate uncoiler 1, a glue spreader 2, an abrasive bin 3, an abrasive conveyor belt 4, an electrostatic sand-planting machine 5, an air knife 6, and a drying furnace 7.

The base material uncoiler 1, the glue spreader 2, the electrostatic sand planting machine 5 and the drying furnace 7 are all conventional equipment, and the arrangement positions of the conventional equipment are the same as those of a system for producing a coated abrasive tool by adopting an electrostatic sand planting method.

The outlet of the electrostatic sand-planting machine 5 is provided with a roller 9 for changing the advancing direction of the base material 8, and one side of the base material 8 implanted with the grinding materials is provided with an air knife 6. The air outlet of the air knife 6 is spaced from the abrasive 10 on the substrate 8, and the spacing forms an air blowing channel. The air outlet direction of the air outlet of the air knife 6 and the advancing direction of the substrate 8 are obliquely arranged. The included angle between the air outlet direction of the air outlet and the advancing direction of the base material is preferably 90-150 degrees. The position of contact between the impinging air curtain from the air knife and the substrate is preferably the position where the substrate is deflected while bypassing the roller 9. In other embodiments, the air knife may be disposed in the linear traveling direction of the substrate.

The gap of the air outlet of the air knife 6 is generally 0.05-0.2 mm. The length of the air outlet is preferably not less than the width of the base material 8. For example, if the width of the coated abrasive to be produced is 1.42 to 1.65m, the length of the air outlet may be set to be the same or slightly larger than the width of the base material. The working principle of the air knife 6 is the principle of the coanda effect, that is, after compressed air enters the air knife, the compressed air is blown out through the air outlet to form a high-speed airflow sheet, and the airflow sheet guides nearby ambient air to form a thin impact air curtain with high strength and large airflow. The corresponding air knife product is a mature product sold in the market and can be selectively purchased according to the actual production requirement.

When the impact air curtain acts on the abrasive on the base material by air pressure, the adjustment of the sand planting angle of the abrasive and the adjustment of the percentage of the abrasive accounting for the total abrasive quantity, which changes in the sand planting angle, can be realized by controlling the distance from the air outlet to the base material, the angle with the advancing direction of the base material, the air pressure and the advancing speed of the base material. When the abrasive is blown, the impact air curtain can directly act on the front-row abrasive contacting with air, the front-row abrasive is correspondingly inclined along the wind direction, the impact air curtain passes through the front-row abrasive and then rebounds through the rear-row abrasive, and can act on the front-row abrasive again, and a part of the front-row abrasive recovers the original sand planting angle or further changes the sand planting angle, and as a result of the comprehensive action of the above factors, the sand planting angle of a part of the abrasive can be changed, and the sand planting angle of a part of the abrasive is very small (the angle change is about 5 degrees). The proportion of the abrasive material with the changed sand planting angle can be controlled within a required range, such as a range of 20-50 percent, by solidifying the parameters such as air pressure and the like in the production practice.

Regarding the sand planting form of the abrasive, the abrasive form of the coated abrasive tool prepared by the conventional electrostatic sand planting is shown in fig. 2, the abrasive on the base material 8 is a vertical abrasive 80, and the adhesive layer on the base material 8 sequentially comprises a primer layer 11, a compound adhesive layer 12 and a super coating 13 from inside to outside. The implantation form of the vertical abrasive is determined by the working process of electrostatic sand planting, and the abrasive generates directional jumping (generally, a thick head faces to the direction of a substrate and a thin head is opposite) under the action of a high-voltage electrostatic field when moving and is adsorbed on the substrate coated with the primer.

The abrasive form of the coated abrasive tool prepared by the invention is shown in fig. 3, the sand planting angle alpha of partial abrasive is changed, and the abrasive state is changed from vertical to inclined. The abrasive on the substrate is a bevel abrasive 81.

A schematic diagram comparing the vertical abrasive with the inclined abrasive in grinding the workpiece 14 is shown in fig. 4, and experiments prove that the angle between the rotation direction of the abrasive belt and the abrasive is less than 90 °, or the contact angle between the abrasive and the workpiece to be processed is greater than 90 °. Grinding is performed in this state, which is advantageous for improving grinding efficiency.

Second, the concrete embodiment of the sand-planting method of the coated abrasive tool of the present invention

The sand planting method of the coated abrasive tool is basically the same as that of the existing manufacturing method, and the difference is that after the sand is planted through static electricity, the sand planting angle of the abrasive material is changed through air pressure formed by air blowing. Then, the drying of the primer solution, the coating and curing of the compound adhesive and the like can all refer to the prior art. The following examples are specifically described below.

Example 2

The sand-implanting method of the coated abrasive tool of the embodiment uses the production system of embodiment 1, and includes the following steps: coating a primer solution on the surface of a base material, performing electrostatic sand planting, then blowing air to an abrasive implanted on the base material, changing the sand planting angle of the abrasive under the air pressure of the blowing air, then drying the primer solution, coating a complex glue solution and drying, coating a super-coating glue solution and drying, integrally curing, and flexing to obtain the composite abrasive.

The abrasive is corundum-zirconia with a particle size of P36. The base material is polyester cloth with the specification of 333g/m². The density of the planting sand is 700g/m²。

The bottom glue layer is prepared from the following raw materials in parts by weight: 48 parts of phenolic resin, 50 parts of calcium carbonate, 1 part of polyoxypropylene glycerol ether defoamer (DF-114, sold in the market) and 1 part of fatty amine salt surfactant (HIT3015, sold in the market); the thickness of the primer layer is 180 μm.

The compound adhesive layer is prepared from the following raw materials in parts by weight: 60 parts of phenolic resin, 40 parts of wollastonite powder, 1 part of pigment, 1 part of polyoxypropylene glycerol ether defoamer, 1 part of fatty amine salt surfactant and 1 part of acrylic copolymer thickener (N-2207, sold in the market); the thickness of the compound glue layer is 200 μm.

The super coating is prepared from the following raw materials in parts by weight: 40 parts of epoxy resin, 60 parts of cryolite powder, 2 parts of polyether ester defoamer (B-104, sold in the market) and 2 parts of perfluoroalkyl mercaptan; the thickness of the super coat was 200 μm.

The primer solution was dried at 100 ℃ for 60 min. The drying of the composite glue solution is carried out for 80min at 100 ℃. The drying of the super-coating glue solution is carried out for 80min at 100 ℃. And then the whole is cured for 5 hours at 120 ℃.

The air pressure of air blowing was 40PSI (nozzle air pressure), and the angle between the air blowing direction and the direction of travel of the substrate was 95 °. The distance from the air blowing port to the substrate was 10cm, and the traveling speed of the substrate was 25 m/min.

In the coated abrasive obtained by the method of this example, the abrasive grains having a grit angle α of 40 ° to α of 50 ° (i.e., the inclined abrasive grains) account for 30 to 33% by number of all the abrasive grains (the grit angle of the remaining abrasive grains may be regarded as unchanged).

Example 3

The sand-implanting method of the coated abrasive tool of the present embodiment is substantially the same as the preparation steps of embodiment 2, except that: the air pressure of air injection is 80PSI, and the angle between the air injection direction and the advancing direction of the base material is 95 degrees. The distance from the air blowing port to the substrate was 10cm, and the traveling speed of the substrate was 25 m/min.

Example 4

The sand-implanting method of the coated abrasive tool of the present embodiment is substantially the same as the preparation steps of embodiment 2, except that: the air pressure of air injection is 180PSI, and the angle between the air injection direction and the advancing direction of the base material is 95 degrees. The distance from the air blowing port to the substrate was 10cm, and the traveling speed of the substrate was 25 m/min.

Examples 5 to 8

The method of making the coated abrasive of examples 5-8 was substantially the same as the method of making example 2, except as set forth in Table 1:

TABLE 1 Experimental parameters for examples 5-8

Item	Example 5	Example 6	Example 7	Example 8
					Air Pressure (PSI)	80	80	80	80
Angle of blowing (°)	120	120	120	120
					Blowing height (cm)	5	10	15	20
Speed (m/min)	25	25	25	25

Examples 9 to 12

The method of making the coated abrasive of examples 9-12 was substantially the same as that of example 2, except as set forth in Table 2:

TABLE 2 Experimental parameters for examples 9-12

Examples 13 to 20

Examples 13-20. the method of making the coated abrasive was substantially the same as that used in example 2, except as set forth in Table 3:

TABLE 3 Experimental parameters for examples 13-20

Third, comparative example

The method for implanting the coated abrasive of the comparative example was different from example 2 in that air blowing was not performed, that is, the same method as that of the conventional coated abrasive.

In the conventional manufacturing method and the manufacturing method of example 2, schematic diagrams of the state of the abrasive after passing through the roller are shown in fig. 5 and 6. In fig. 5, after the abrasive on the base material 8 passes through the roller 9, the sand planting angle is kept unchanged at 90 °. In fig. 6, after the blowing, the sand-planting angle of the abrasive is changed from vertical to inclined.

Fourth, example of experiment

The products obtained in examples 2 to 20 and comparative example were made into coated products 50mm × 2000mm wide, using SUS-304 stainless steel as a workpiece to be processed (25mm × 25mm × 300mm), a rotation speed of a coated abrasive machine was 1700rpm, a grinding pressure was 10kg, a grinding time was 3min (1 cycle), and each coated abrasive was tested for 20 cycles.

Specific grinding energy SGE is one of the criteria for measuring grinding efficiency, and represents the energy consumed to remove a certain volume of workpiece. The formula for SGE is: SGE is P/MRR. P is the electric energy consumed in the grinding process, MRR is the removal amount (grinding amount) of the material, and in the test, a measuring device in the abrasive belt grinding testing machine can measure the removal amount of the material in the grinding process and the electric energy consumed correspondingly.

The total grinding amount of each example and comparative example was examined, and the results are shown in tables 4 to 7.

TABLE 4 inclined grit fraction and Total cut comparison of examples 2-4

TABLE 5 inclined grit fraction and Total cut comparison of examples 5-8

TABLE 6 inclined grit fraction and Total cut comparison of examples 9-12

TABLE 7 inclined grit fraction and Total cut comparison of examples 13-20

The data of the SGE and the cumulative grinding amount of examples and comparative examples are shown in tables 8 to 11, and the corresponding drawings are shown in FIGS. 7 to 10.

TABLE 8 Total grindings and SGE data for examples 2-4 and comparative examples

TABLE 9 Total grindings and SGE data for examples 5 to 8 and comparative examples

TABLE 10 Total grindings and SGE data for examples 9-12 and comparative examples

Example 11 Total grinding yields and SGE data for examples 13-20

As can be seen from the figure, the abrasive belts of the examples had a higher grinding amount at the same SGE compared to the comparative examples, while the SGE of the abrasive belts of the examples was significantly reduced at the same grinding amount, indicating a higher grinding efficiency.

From the above grinding experiment results, it is known that the grinding performance of the abrasive belt can be enhanced by adjusting the sand-planting angle of the abrasive, compared with the comparative example. Moreover, the abrasive belt product with excellent grinding performance can be obtained when the air pressure is 80-130PSI, the blowing angle is 100-130 degrees, and the blowing height is about 5-15 cm. The abrasive belts of the optimized examples had higher grinding yields at the same SGE compared to the comparative examples, while the SGE of the abrasive belts of the examples was significantly reduced at the same grinding yields, indicating higher grinding efficiencies.

Claims

1. A sand planting method of a coated abrasive tool is characterized by comprising the following steps: applying a non-mechanical external force to the abrasive to obliquely arrange a part of the abrasive with respect to the surface of the base material before the abrasive is dried after being adsorbed to the base material; the non-mechanical external force is wind power; the force application position of the wind power is positioned at the turning position when the base material moves before the abrasive material is adsorbed to the base material and then dried; the wind power forms an impact air curtain with the width not less than the width of the base material, and the abrasive is obliquely and downwards blown; the pressure of the wind power is 80-130PSI, the wind power is provided by a blowing device, the height of a blowing opening of the blowing device from the base material is 5-15cm, the angle between the blowing direction and the base material is 100-135 degrees, and the advancing speed of the base material is 10-40 m/min.

2. A method of implanting a coated abrasive according to claim 1, wherein the force applied by the wind is applied in a direction opposite to a traveling direction of the base material.

3. A method of implanting a coated abrasive according to claim 1 or 2 in which the abrasive has a particle size of 5 to 1400 μm.

4. A method of sanding a coated abrasive according to claim 1 or 2, wherein the obliquely arranged abrasive has a sanding angle α of 30 ° α or more < 90 ° and abrasive grains having a sanding angle α of 30 ° α or more < 90 ° account for 20 to 50% by number of all the abrasive grains.

5. A coated abrasive production system for carrying out a sand-implanting method of the coated abrasive according to claim 1, comprising a primer coating apparatus for coating a primer solution on a substrate; the electrostatic sand planting equipment is used for implanting abrasive materials on the base material coated with the primer; the compound glue coating equipment is used for coating compound glue solution; the glue solution curing equipment is used for curing the glue solution on the base material; it is characterized by also comprising:

the force application equipment is arranged at the downstream of the electrostatic sand planting equipment; applying a non-mechanical external force to the abrasive to cause a portion of the abrasive to be disposed obliquely with respect to the substrate surface; the force application equipment is wind power equipment; the force application position of the wind power device on the base material is located at the turning position when the base material travels.

6. The coated abrasive production system of claim 5, wherein the wind power device is a gas blowing device having a blowing port from which gas is blown and applies air pressure to the abrasive implanted on the substrate, thereby changing the angle of sand implantation of the abrasive.

7. The coated abrasive article production system of claim 6, wherein the blowing port is a slit having a length extending in a width direction of the substrate.