Solvent-free environment-friendly material abrasive paper and preparation method thereof

Abstract

The invention discloses solvent-free environment-friendly material abrasive paper and a preparation method thereof, and relates to the technical field of abrasive paper, the solvent-free environment-friendly material abrasive paper comprises the following components: a substrate material, a thermoplastic material and an abrasive material, the substrate material provides a basic supporting structure for the abrasive paper, the thermoplastic material is in a molten state when heated to 230 DEG C and forms a stable structure after being cooled, and the abrasive material is ground; the abrasive material is uniformly distributed on the surface of the substrate material coated with the thermoplastic material, so that the grinding function of the abrasive paper is realized. According to the solvent-free environment-friendly material abrasive paper and the preparation method thereof, the abrasive paper adopts a special thermoplastic material to replace a traditional adhesive, and the thermoplastic material has good plasticity in a heating state, can be tightly combined with an abrasive material and a substrate material, and forms a stable structure after being cooled, so that the abrasive material is firmly bonded, and the abrasive material is prevented from being damaged. The thermoplastic material is completely non-toxic and harmless and does not contain any chemical reagent, so that the harm to the environment and human bodies is eliminated from the source.

Description

Technical Field

[0001] The invention relates to the technical field of sandpaper, in particular to sandpaper made of a solvent-free environmentally friendly material and a preparation method thereof. Background Art

[0002] In the production process of traditional sandpaper, adhesives are usually used to bond the abrasive and the base material. Most of these adhesives contain a large amount of organic solvents and chemical reagents. In the production process of sandpaper, the volatilization of organic solvents will cause serious air pollution and endanger the health of production workers. Later, due to environmental protection needs, water-based adhesive processes were widely used in the production of sandpaper. Despite this, the emission of free benzene and free phenol is still very high.

[0003] At the same time, during the use of sandpaper, as the abrasive wears away, the chemicals in the adhesive may be released, causing potential harm to the environment and users. Moreover, after the traditional sandpaper is discarded, it is difficult to degrade naturally due to the presence of adhesives, which puts a greater burden on the environment.

[0004] Therefore, it is urgent to improve this shortcoming. The present invention studies and improves the existing structure and shortcomings, and provides a solvent-free environmentally friendly sandpaper and a preparation method thereof. Summary of the invention

[0005] The purpose of the present invention is to provide a solvent-free environmentally friendly sandpaper and a preparation method thereof, so as to solve the problems of environmental pollution, health hazards and difficulty in degradation caused by the use of adhesives containing solvents and chemical reagents in the existing traditional sandpaper mentioned in the above background technology.

[0006] To achieve the above-mentioned purpose, the present invention provides the following technical solution: a sandpaper made of solvent-free environmentally friendly material, whose components are as follows: a base material, a thermoplastic material and an abrasive, the base material provides a basic support structure for the sandpaper, the thermoplastic material is in a molten state when heated to 230°C, and forms a stable structure after cooling, which is used to firmly bond the abrasive and the base material, and the abrasive is evenly distributed on the surface of the base material coated with the thermoplastic material to realize the grinding function of the sandpaper.

[0007] Furthermore, the base material is one of paper, cloth, PET or sponge.

[0008] Furthermore, the abrasive is one or more of silicon carbide, aluminum oxide, ceramics, and zirconium corundum.

[0009] Furthermore, the method for preparing the sandpaper of the solvent-free environmentally friendly material comprises the following steps: pretreatment of the substrate material: selecting paper, cloth or sponge as the substrate material and placing it in an unwinding device;

[0010] Thermoplastic material coating: put the selected thermoplastic material into a heating furnace, heat it to 230℃ to make it completely melted, and transport the molten thermoplastic material to the coating equipment through a metering pump. Use casting, roller coating or doctor blade coating to evenly coat the thermoplastic material on the base material with the abrasive already distributed. The coating thickness is controlled at 0.2-25mm. The base material after gluing is kept at a temperature of 200℃ to stabilize its performance;

[0011] Abrasive distribution: According to the different mesh requirements of sandpaper, select abrasives of corresponding particle size, screen the abrasives through a vibrating screen or airflow sorting equipment to remove impurities and unqualified particles, and then use an automatic spreading device or an electrostatic sand planting device to evenly spread the screened abrasives on the surface of the pretreated base material to ensure that the abrasives are evenly distributed and the amount of abrasive per unit area meets the design requirements;

[0012] Cooling and curing: After coating, the sandpaper immediately enters the cooling device, and the thermoplastic material is quickly cooled and cured by air cooling or water cooling. The cooling speed is controlled at -5-5℃, 15m / min;

[0013] Secondary gluing: If secondary gluing is required, roll or scraper coating should be performed for the second time after winding and cooling completely to make the abrasive bond more firmly or to apply anti-clogging coating.

[0014] The present invention provides a solvent-free environmentally friendly sandpaper and a preparation method thereof, which has the following beneficial effects:

[0015] 1. The sandpaper of the present invention adopts a special thermoplastic material to replace the traditional adhesive. The thermoplastic material has good plasticity in a heated state, can be closely combined with the abrasive and the base material, and forms a stable structure after cooling, thereby firmly bonding the abrasive. The thermoplastic material is completely non-toxic and harmless, does not contain any chemical reagents, and eliminates the harm to the environment and human body from the source.

[0016] 2. Since the present invention does not use adhesives containing organic solvents and chemical reagents, no volatile organic compounds (VOCs) will be generated during the production process, reducing air pollution; during use, no harmful chemicals will be released, protecting the use environment and the health of users; after disposal, the sandpaper uses thermoplastic materials that are naturally degradable or easily recyclable, greatly reducing the burden on the environment.

[0017] 3. The stable structure formed by the special thermoplastic material in the present invention during the heating and cooling process can provide reliable bonding force for the abrasive, ensuring that the abrasive is not easy to fall off during the use of sandpaper, thereby ensuring the service life and grinding effect of the sandpaper. Since the flexibility of the special thermoplastic material far exceeds that of ordinary sandpaper, it is more advantageous to use it in flexible grinding. The non-toxic and harmless material properties ensure that the sandpaper will not cause harm to personnel and the environment in the production link, use link or waste disposal link, thereby improving the safety of the entire product life cycle. DETAILED DESCRIPTION

[0018] The following examples are used to illustrate the present invention, but they are not intended to limit the scope of the present invention.

[0019] Embodiment 1

[0020] Preparation of sandpaper with release paper as base material:

[0021] Pretreatment of base material: density 120g / m 2 The release paper roll is used as the base material. The release paper roll is installed on the unwinding device, and the running speed of the unwinding device is set to 10m / min to make the paper roll unwind smoothly. Then, a continuous calendering roller is used to repeatedly and accurately control the thickness of the base film, and the bonding force between the release paper and the thermoplastic material can be enhanced.

[0022] Thermoplastic material coating: Select a thermoplastic polyester elastomer as the thermoplastic material and put it into the heating furnace. Turn on the heating device and raise the furnace temperature to 230°C to completely melt the thermoplastic material. The molten thermoplastic material is delivered to the coating equipment at a flow rate of 30ml / min through a metering pump with an accuracy of ±0.5ml / min. Adjust the gap of the coating equipment and precisely control the amount of glue applied so that the thermoplastic material is evenly coated on the surface of the pretreated sponge roll, and the coating thickness is controlled at 0.5mm. After the coating is completed, the glued sponge is sent to an oven at a temperature of 200°C and kept for 10 minutes to stabilize its performance.

[0023] Abrasive distribution: This time, 180-mesh sandpaper was prepared, and silicon carbide abrasive with a particle size of 80-100 μm was selected. The silicon carbide abrasive was poured into a vibrating screen, and the vibration frequency of the vibrating screen was set to 50 Hz. The abrasive was screened to remove impurities and particles with unqualified particle sizes. Then, an automatic material spreading device was used to scatter the abrasive at a rate of 15 g / m 2 The screened silicon carbide abrasive is evenly spread on the surface of the kraft paper coated with thermoplastic material, ensuring that the deviation of the abrasive distribution uniformity is controlled within ±3%.

[0024] Cooling and solidification: After coating and spreading, the sandpaper immediately enters the air cooling device, and the fan speed is adjusted to 8m / s to quickly cool and solidify the thermoplastic material. The cooling speed is controlled at 2℃ / min, and the transmission speed is 15m / min. The thermoplastic material forms a dense structure and firmly bonds the abrasive. After the quality test of the cooled sandpaper, the abrasive shedding rate is less than 5%, which meets the product quality standards.

[0025] Secondary gluing (no such requirement, this step is skipped): Since the secondary gluing is not required in this embodiment, the sandpaper directly enters the next step of packaging process.

[0026] Embodiment 2

[0027] Preparation of sandpaper with cloth as base material:

[0028] Pretreatment of base material: cotton cloth with a warp and weft density of 30 strands / cm×30 strands / cm is selected as the base material. The cotton cloth roll is placed on the unwinding device and unwinds at a speed of 12m / min. Subsequently, the cotton cloth is chemically treated by soaking it in a 5% sodium hydroxide solution for 15 minutes, then rinsed with clean water and dried to activate the surface of the cotton cloth and increase the bonding strength with the thermoplastic material.

[0029] Thermoplastic material coating: Thermoplastic polyurethane elastomer is selected as the thermoplastic material and placed in a heating furnace to heat to 230°C to melt. The molten thermoplastic material is transported to the scraper coating equipment at a flow rate of 35ml / min through a metering pump, and the thermoplastic material is evenly coated on the surface of the cotton cloth. The coating thickness is controlled at 1mm. The coated cotton cloth is kept at 200°C for 12 minutes to stabilize its performance.

[0030] Abrasive distribution: In view of the demand for 240-grit sandpaper, aluminum oxide abrasive with a particle size of 60-80μm is selected. The aluminum oxide abrasive is screened by using airflow sorting equipment and the wind pressure is set to 3000Pa. Then, an electrostatic sand planting device is used to evenly plant the screened aluminum oxide abrasive on the surface of the cotton cloth coated with thermoplastic material. The abrasive amount per unit area is controlled at 18g / m 2 , ensuring uniform distribution of abrasive.

[0031] Cooling and curing: After entering the water-cooling cooling device, the coolant temperature is maintained at 15°C, so that the sandpaper is conveyed at a speed of 15m / min, and the thermoplastic material is quickly cooled and cured. The cooling rate is controlled at -3°C / min. After testing, the tensile strength of the sandpaper reaches 80N / cm, which meets the use requirements.

[0032] Secondary coating: Since the product design requires anti-clogging coating treatment, the sandpaper is scraped for the second time after winding and completely cooling. The coating material is a special coating material containing fluoride, and the coating thickness is controlled at 0.1mm. After coating, the anti-clogging performance of the sandpaper is significantly improved. During the continuous grinding process, the grinding chips are not easy to accumulate, and the grinding effect is continuous and stable.

[0033] Embodiment 3

[0034] Preparation of sandpaper with sponge as base material:

[0035] Pretreatment of base material: A polyester sponge with a porosity of 60% was used as the base material. The sponge roll was mounted on an unwinding device and unwound at a speed of 8 m / min. Then, the sponge surface was first polished with sandpaper by combining mechanical polishing with chemical treatment, and then the sponge was soaked in a 3% acrylic emulsion for 20 minutes, taken out and dried, to improve the bonding performance between the sponge surface and the thermoplastic material.

[0036] Thermoplastic material coating: Thermoplastic polyolefin elastomer is used as the thermoplastic material, heated to 230℃ in a heating furnace to melt. It is transported to the casting coating equipment at a flow rate of 25ml / min through a metering pump, and evenly cast on the sponge surface. The coating thickness is controlled at 2mm. The glued sponge is kept at 200℃ for 15 minutes to stabilize the performance.

[0037] Abrasive distribution: For 120-grit sandpaper, choose a mixed abrasive of silicon carbide and aluminum oxide with a particle size of 120-150μm (mass ratio of 3:2). After screening through a vibrating screen, use an automatic spreading device to spread the mixed abrasive at a rate of 20g / m 2 Spread the amount evenly on the sponge surface to ensure that the mixed abrasive is evenly distributed to meet the design requirements.

[0038] Cooling and curing: Air cooling, wind speed set to 6m / s, cooling speed controlled at 3℃ / min, at a conveying speed of 15m / min, the thermoplastic material cools and solidifies, firmly bonding the abrasive. After testing, the sandpaper shows good deformation performance in the flexible grinding scene, and the abrasive is not easy to fall off.

[0039] Secondary coating: To enhance the bonding strength of the abrasive, a second coating is performed.

[0040] For the same thermoplastic material, the roller coating thickness is controlled at 0.3mm. After the second coating, the abrasive shedding rate of the sandpaper is further reduced during use, and the service life is extended.

[0041] It can be seen from the above embodiments that the solvent-free environmentally friendly material sandpaper and the preparation method thereof of the present invention can stably produce sandpaper products with excellent performance, and have excellent performance in environmental performance, bonding performance, polishing effect, etc., and have good market application prospects.

[0042] The embodiments of the present invention are given for the purpose of illustration and description, and are not intended to be exhaustive or to limit the invention to the disclosed forms. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiments are selected and described in order to better illustrate the principles and practical applications of the present invention and to enable those of ordinary skill in the art to understand the present invention and thereby design various embodiments with various modifications suitable for specific uses.

Claims

1. A solvent-free environmentally friendly sandpaper, characterized in that: Its components are as follows: base material, thermoplastic material and abrasive. The base material provides the basic support structure for sandpaper. The thermoplastic material is molten when heated to 230°C and forms a stable structure after cooling, which is used to firmly bond the abrasive and the base material. The abrasive is evenly distributed on the surface of the base material coated with the thermoplastic material to realize the grinding function of the sandpaper.

2. The solvent-free environmentally friendly sandpaper according to claim 1, characterized in that: The base material is one of paper, cloth, PET or sponge.

3. The solvent-free environmentally friendly sandpaper according to claim 2, characterized in that: The abrasive is one or more of silicon carbide, aluminum oxide, ceramics, and zirconium corundum.

4. A method for preparing a solvent-free environmentally friendly sandpaper as claimed in claim 3, characterized in that: The following steps are included: Material pretreatment: Select paper, cloth, PET or sponge as the base material and put it into the unwinding equipment; Thermoplastic material coating: put the selected thermoplastic material into a heating furnace, heat it to 230℃ to make it completely melted, and transport the molten thermoplastic material to the coating equipment through a metering pump. Use casting, roller coating or doctor blade coating to evenly coat the thermoplastic material on the base material with the abrasive already distributed. The coating thickness is controlled at 0.2-25mm. The base material after gluing is kept at a temperature of 200℃ to stabilize its performance; Abrasive distribution: According to the different mesh requirements of sandpaper, select abrasives of corresponding particle size, screen the abrasives through a vibrating screen or airflow sorting equipment to remove impurities and unqualified particles, and then use an automatic spreading device or an electrostatic sand planting device to evenly spread the screened abrasives on the surface of the pretreated base material to ensure that the abrasives are evenly distributed and the amount of abrasive per unit area meets the design requirements; Cooling and curing: After coating, the sandpaper immediately enters the cooling device, and the thermoplastic material is quickly cooled and cured by air cooling or water cooling. The cooling speed is controlled at -5-5℃, 15m / min; Secondary gluing: If secondary gluing is required, roll or scraper coating should be performed for the second time after winding and cooling completely to make the abrasive bond more firmly or to apply anti-clogging coating.