JPS639950B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention uses polyester fiber non-woven fabric, which has the characteristics of polyester synthetic fibers, such as high Young's modulus, hardness, and excellent rebound properties, as the constituent fiber skeleton of the abrasive material, and appropriately selects the make coat material and size coat material to cover the fiber skeleton. The present invention relates to a structure of a polyester nonwoven fabric abrasive material that satisfies its function as an abrasive material when used. Conventionally, polyamide fibers such as nylon 6 and 6.6 nylon fibers have been mainly used as fibers for forming webs in nonwoven abrasive materials, and in addition to these, SBR,
The majority of products are manufactured by using a make coat of thermoplastic resin such as NBR latex, acrylic ester, or vinyl chloride emulsion, and then size-coating thermosetting resin such as phenol, epoxy, or urethane. When the makeup and size coat materials of such polyamide fiber nonwoven abrasive materials gradually fall off due to the abrasive grinding action, they lose their stiffness and easily lose their shape due to their characteristics of low Young's modulus (easy to stretch) and flexibility. However, some products have the disadvantage that they become unusable even though they are not worn out. Furthermore, polyamide fibers are easily deteriorated by free phenol, and the state of deterioration is not constant due to variations in the phenol resin and heat treatment conditions, which has an adverse effect on polishing performance. Additionally, polyamide fiber webs tend to be thinner and suffer from higher fiber packing densities. This is fiber: resin:
This is because the weight ratio of abrasive grains is limited due to polishing performance, and nonwoven abrasive materials made from polyamide fibers are only about half as thick as those using polyester fibers. This is because the abrasive material has a high fiber packing density. Therefore, there is a drawback that clogging with the object to be ground occurs quickly. In order to eliminate these drawbacks, polyester fiber 1 is used as shown in Figure 1, and after applying a make coat 2 of SBR, NBR latex, acrylic ester resin emulsion, etc. in the same way as polyamide fiber, it is coated with phenol, epoxy, urethane, etc. A nonwoven abrasive material in which abrasive grains 3 are fixed with resin or the like and size coated 4 has also been developed. However, this abrasive material has a weak adhesion strength (adhesive strength) between the polyester fiber 1 and the make coat material 2, and cannot fully demonstrate its function as a make coat material. Although it is nearly twice as thick as the polyamide fiber nonwoven abrasive material, it loses bulk and becomes thinner as it is used.Furthermore, the fibers, make coat material, and size coat material 4 peel off, and the polyester fibers eventually peel off. The drawback is that only the fiber skeleton remains and the grinding ability is lost. A possible reason for this is that synthetic fibers that do not have water absorption properties, such as polyester fibers, have almost no adhesive strength with synthetic resins such as SBR and NBR, so the bond between the make coat material 2 and the polyester fibers 1 There is a boundary layer 5 that is not bonded to the surface of the abrasive material, and therefore, this type of abrasive material peels off from this boundary layer during use.
The drawback is that it is bulky and wears out quickly. This is because polyamide fibers have amide bonds - CO.
A synthetic chain polymer formed by NH-, adipic acid (HOOC(CH ₂ ) ₄ COOH), which is an acidic molecule, and hexamethylenediamine (H ₂ N(CH ₂ ) ₆ NH ₂ ), which is a basic molecule, are Hexamethylenediamide [-NH
(CH ₂ ) ₆ NH−CO (CH ₂ ) ₄ CO−]n, whereas polyester fibers

[Formula] and ethylene glycol (HOCH ₂ CH ₂ OH) are condensed together. It has a structural formula of One of the differences between the two is the water absorption rate, which is 3-5% for polyamide fibers, while it is very low at 0.4-0.5% for polyester fibers.Also, as mentioned above, polyamide fibers have a polar content in their molecules. At present, polyamide fibers are used because they have good adhesion to SBR, NBR, or acrylic ester resins used as make coat materials because they have NH groups. From this point of view, the present invention was developed as a result of various studies to improve the adhesive strength between polyester synthetic fibers with low water absorption capacity and make coat materials. It was found to be most suitable as Most of the terminal groups of the above polyester resin are hydroxyl groups (-OH), and sodiosulfo groups (SO ₃ Na) are added at random intervals along the main chain to make it water dispersible. HMDI (hexamethylene diisocyanate) -OCN- has excellent adhesive strength to synthetic fibers and is used as a make coat material.
The terminal NCO of the polyurethane emulsion whose main component is (CH ₂ ) ₆ -NCO- reacts with the terminal hydroxyl group (-OH) of the water-dispersed polyester resin to form a urethane bond (-NHCO-), resulting in three-dimensional crosslinking. Reticulate. Therefore, as a make coat material, a polyester synthetic fiber and a linear water-dispersed polyester resin are used as intermediates, and the polyurethane resin is crosslinked together to form a strong film. In other words, the urethane resin, polyester resin, and polyester synthetic fiber are three-dimensionally cross-linked, so they have strong adhesion to the polyester synthetic fiber, and the urethane bond creates a cross-linked network, which improves abrasion resistance and rebound. A rich and very strong film is formed on the surface of polyester synthetic fibers. The present invention provides the above-mentioned polyester synthetic fiber web.
By composing the abrasive material with a combination composite of water-dispersed polyester resin and polyurethane resin, it is more wear resistant than conventional polyester fiber abrasive base materials, and is more wear-resistant than abrasive base materials make-coated with polyamide fibers and SBR or NBR latex. Furthermore, it forms an ideal abrasive material with superior rebound, abrasion resistance, and adhesive strength. Furthermore, the use of polyester synthetic fibers is characterized by the ability to obtain bulky abrasive materials;
By mixing polyester synthetic fibers with a lower melting point into ordinary polyester synthetic fibers with a higher melting point, the penetration of the dispersed particles into the inside of the web is insufficient in the conventional primary temporary bonding process by sprinkling a binder. However, it was not possible to obtain an abrasive base material with a thickness of 30 mm or more due to the disadvantage that it was not possible to bond uniformly to the inside, but it has now become possible to obtain an abrasive base material of any thickness. That is, by mixing about 5 to 40% of low melting point polyester synthetic fibers, after forming the web, the melting point of the low melting point polyester synthetic fibers or higher,
This is because a primary tacking nonwoven fabric mat can be formed by heating at a temperature below the melting point of high melting point polyester synthetic fibers, and after secondary tacking adhesion by impregnating the tacking mat with polyester resin, a polyurethane dip make coat is applied to this tacking mat. This made it possible to form an abrasive material with a thickness of 30 mm or more. Next, the configuration of the present invention will be explained based on the drawings. FIG. 2 shows a cross section of a single fiber of the fiber skeleton constituting the polyester nonwoven abrasive material of the present invention.
is a polyester synthetic fiber; 7 is a polyester resin that temporarily binds the polyester synthetic fibers together; 8 is a polyurethane resin that serves as a make coat layer; and 9 is an abrasive grain 3 that is further bonded onto the polyurethane resin. This shows the size coat layer made of phenolic resin applied for this purpose. The interface 10 between the polyester resin 7 and the polyurethane resin 8 is firmly bonded by urethane bonding, and there is no boundary layer at the bond between the polyester synthetic fiber 6 and the polyester resin 7, resulting in complete adhesion and strong bonding. It forms a part. Next, the present invention will be explained in more detail with reference to Examples. Example 1 A random web having a weight of 350 g/m ² was formed from polyester fibers having a thickness of 30 denier and 38 mm using a Land Weber machine. Next, a binder liquid having the following composition is sequentially sprayed on both the front and back sides of the web and drying is repeated to obtain a primary temporary bonded nonwoven fabric mat in which the fibers are bonded to each other. Mixing ratio Water-dispersed polyester resin 100 parts Melamine resin 30 parts Catalyst 3 parts Concentration 30% The amount of the above mixed solution sprayed is 100 parts on both the front and back surfaces.
g/m ² (solid content), and the polyester resin was completely fixed to form a primary temporarily fixed nonwoven fabric mat having a thickness of 30 mm and a weight of 550 g/m ² . Next, using this temporarily fixed nonwoven fabric mat as a base material,
It was immersed in a urethane resin emulsion with the following formulation. Composition ratio Urethane resin emulsion 100 parts Melamine resin 30 parts Catalyst 3 parts Water Concentration 30% Squeeze the excess liquid with a mangle and adjust the adhesion amount to 250 g/m ² . After drying, the weight is 800 g/m ² and the thickness is 30 mm polyurethane. A secondary bonded nonwoven fabric mat having a make coat layer coated with a resin was formed. Furthermore, a non-woven fabric mat with a make coat was immersed in a size coat material solution containing abrasive grains with the following composition, and the composition ratio was 100 parts phenol resin, 200 parts abrasive grains, 200 parts methyl alcohol, a small amount of pigment, concentration 70%, adhesion amount 750 g/m2. ² (solid content), and is dried and heated to fix the abrasive grains on the make coat layer of the secondary bonded nonwoven mat, and form a size coat layer coated with phenolic resin. . The resulting polyester nonwoven abrasive had a weight of 1550 g/m ² and a thickness of 30 mm. Example 2 A bulky land web having a weight of 600 g/m ² and a thickness of 60 mm was formed using a land webber machine using a mixed fiber of 70% polyester fibers of 60 denier and 30% of low melting point polyester fibers of 15 denier x 51 mm. This land web was sandwiched between punch metals with gauges adjusted to a spacing of 50 mm above and below, introduced into a dryer kept at 150℃, and heated to reduce the weight to 600℃.
A nonwoven fabric mat having a controlled weight of ⁵⁰ mm and a thickness of 50 mm was obtained. Next, it was immersed in the same polyester resin blend solution as in Example 1 and squeezed with a mangle so that the solid content was 180 g/m ² to form a primary temporary nonwoven mat with a weight of 780 g/m ² and a thickness of 50 mm. Formed. Subsequently, it is immersed in the same urethane resin mixture solution that forms the make coat layer as in Example 1, squeezed with a mangle so that the solid content is 390 g/m ² , and dried to coat the surface of the primary temporary nonwoven fabric mat with urethane. Weight 1170g/m ² and thickness of resin make coat layer
A 50 mm secondary bonded nonwoven mat was obtained. Next, the secondary adhesive nonwoven fabric mat was immersed in a resin/abrasive grain mixture having the composition shown below. Mixing ratio Urethane resin prepolymer 100 parts Abrasive grains 200 parts Methyl isobutyl ketone pigment A little Concentration 70% Squeezed with a mangle to a coating amount of 1000 g/m ² (solid content), and dried and heated to dry and heat the secondary base mat. A polyester nonwoven abrasive material having a weight of 2170 g/m ² and a thickness of 50 mm was obtained by fixing abrasive grains on a make coat layer and forming a size coat layer made of polyurethane resin. The polyester nonwoven fabric abrasive material of the present invention obtained in Example 1 and the polyamide fiber web of the same denier and weight as in Example 1 as a comparative example, as well as the same amount of polyester and polyurethane resin adhesion.
A polyamide nonwoven abrasive material was prepared by depositing SBR latex and further depositing an abrasive grain-containing phenolic resin as a size coat layer in the same manner as in Example 1. The thickness of this polyamide nonwoven abrasive was 15 mm. The polyester nonwoven abrasive of the present invention and the conventional polyamide nonwoven abrasive of the comparative example were punched into wheels with a diameter of 20 cm, and a grinding test was conducted on a vinyl chloride resin plate at a rotation speed of 500 rpm and a load of 10 kg. Shown in the figure. The polyamide nonwoven abrasive material gradually becomes clogged due to the PVC debris being ground, and as shown in the figure, the grinding ratio decreases significantly over time. Also, the wheels gradually lost their stiffness and became soft, until they could no longer withstand rotation. On the other hand, the polyester nonwoven abrasive material of the present invention has a coarse mesh, does not show a decrease in grinding ratio due to clogging, and has a high Young's modulus of polyester fibers and a three-dimensional By cross-linking, rebound resilience,
Excellent adhesion and gradual reduction in grinding ratio were obtained. Next, as Comparative Example 2, a comparison was made with a conventional polyester fiber nonwoven abrasive material A made using the same SBR and phenolic resin as in Comparative Example 1 using a polyester fiber web with the same denier and weight as in Example 1. In order to compare the performance of the polyamide nonwoven abrasive material B of Example 1 and the polyester nonwoven abrasive material C of the present invention, the tensile strength, tear strength,
The results of measuring the compressive elastic recovery rate are shown in FIGS. 4 and 5. The above tensile strength was measured under the following test conditions. Testing machine: Shimadzu Autograph test piece 5cm wide,
Clamp distance 10cm, tensile speed 300mm/min, tear strength measured by JIS single tongue method, and compression recovery rate by compressing each 20mm thick test piece to 2mm.
After being left for 1 hour, the compression was released, and the thickness after 1 minute was measured to calculate the recovery rate. As shown in Figure 4, the polyester nonwoven abrasive material C of the present invention has greatly improved tensile and tear strength compared to the conventional polyester fiber nonwoven abrasive material A, and has a strength equivalent to or higher than that of the conventional polyamide nonwoven abrasive material B. Furthermore, as shown in FIG. 5, the compressive elastic recovery rate was very superior to that of the nonwoven abrasive materials A and B of Comparative Examples 1 and 2. The present invention, configured as described above, has excellent abrasion resistance and adhesion due to the combination of the excellent elastic properties of polyester fibers and the urethane bonding of polyester resin and urethane resin, and is suitable for make coat and size coat layers. There is little resin shedding, and the adhesive strength between polyester fiber and polyester resin is particularly good, so it connects the bulky fiber skeleton of the abrasive base material, has excellent compression recovery rate and rebound resilience, does not clog, and improves grinding performance. This invention has a variety of effects, including the following: it is ideal as a household scrubbing brush, and as an industrial abrasive for finishing the grinding of wood, metal, etc.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of fibers constituting a conventional polyester fiber nonwoven abrasive, FIG. 2 is a cross-sectional view of fibers constituting a polyester nonwoven abrasive according to an embodiment of the present invention, and FIG. FIG. 4 is a curve diagram showing the progress of grinding ratio with Comparative Example, FIG. 4 is a curve diagram showing the tensile strength and tearing strength of the present invention and Comparative Example 1 and Comparative Example 2, and FIG. be. DESCRIPTION OF SYMBOLS 1... Polyester fiber, 2... Make coat resin, 3... Abrasive grain, 4... Size coat resin, 5... Boundary layer, 6... Polyester synthetic fiber, 7... Polyester resin, 8... Polyurethane resin, 9...Size coat layer, 10...Boundary surface.

Claims (1)

[Claims] 1. A web made of polyester synthetic fiber,
A base material is a temporarily fixed nonwoven fabric mat temporarily fixed with a polyester resin, the surface of the constituent fibers of the base material is coated with a polyurethane resin to form a make coat layer, and a layer of aluminum oxide, silicon carbide, etc. is further coated on the make coat layer. A polyester nonwoven abrasive material characterized by forming a size coat layer formed by coating with a thermosetting resin such as epoxy, phenol, or polyurethane containing abrasive grains. 2. The polyester nonwoven abrasive material according to claim 1, wherein the temporarily fixed nonwoven fabric mat is formed containing low melting point polyester fibers.