JPS6217634B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ultraviolet curing bind tape used as a fastening member for laminated cores or windings of electrical equipment. Ultraviolet curable bind tape cures quickly by irradiating it with ultraviolet rays, so in the production of bind-wound laminated cores or wound wires, it saves labor in tape curing work, reduces curing time, saves energy, and shortens manufacturing time. It is very useful in that it is possible. The method of manufacturing a bind-wound laminated core or wound wire using UV-curable bind tape is to wrap the bind tape in several layers while applying tension.
The process consists of curing the resin by irradiating it with ultraviolet light. Applying tension when wrapping bind tape is absolutely necessary in order to strengthen the adhesion between the tape layers and increase the strength of the bind tape after curing by allowing each tape layer to harden as one after the resin hardens. . However, because the UV-curable resin contained in conventional UV-curable bind tape has a relatively low molecular weight, it lacks so-called stiffness, has low tape strength when uncured, and breaks when tension is applied when winding the tape. There were flaws. In other words, if tension is applied uniformly along the lateral direction of the tape, it will not break, but
In actual laminated cores or windings, the surface in contact with the tape has unevenness, so the tension is not applied uniformly to the tape, so the bond between the fibers due to the impregnated resin is destroyed first, and the fibers become separated and unravel. When the tension is concentrated on one fiber in the fibers, this fiber is broken, and the tension is further concentrated on the next fiber, causing it to break. In this way, it is thought that the rupture due to the concentrated tension occurs one after another, and finally the entire bind tape ruptures. Furthermore, conventional UV-curable bind tapes have relatively low tackiness in an uncured state, and therefore have the disadvantage that the tape layers cannot be integrated with each other after curing unless strong tension is applied. The purpose of the present invention is to provide a tape that does not have the above-mentioned drawbacks, has high bonding strength of fibers even when uncured, does not break even when winding tension is applied, and has appropriate adhesiveness. An object of the present invention is to provide an ultraviolet curable bind tape that tightly adheres each tape layer when wet. The present invention comprises a resin component selected from the group consisting of a resin component that is a mixture of an ultraviolet curable resin, which is a vinyl ester synthesized from an epoxy resin and (meth)acrylic acid, and a phenoxy resin, and a glass cloth or glass yarn with no folded weft threads. The present invention relates to an ultraviolet curable bind tape characterized by being made of glass fiber. The glass fiber according to the invention uses a glass cloth or a glass yarn without weft turns, such as a unidirectionally aligned glass yarn. Glass cloth has conventionally been available with or without folded wefts, but in the present invention, among these, glass cloth without folded wefts is used. As the ultraviolet curable resin according to the present invention, a vinyl ester synthesized from an epoxy resin and (meth)acrylic acid is used. As an epoxy resin,
There are no particular restrictions, and the oxirane ring is
It can be used as long as it is a compound having at least
Epoxy resins obtained by reacting bisphenol A, hydrogenated bisphenol A, bisphenol F or novolak resin with epichlorohydrin, or (methyl)glycidyl ether, (methyl)glycidyl ester, (methyl)glycidylamine type epoxy resins, or Aliphatic or cycloaliphatic epoxy resins or epoxy resins having heterocycles can be used. One or more vinyl esters obtained from these epoxy resins and (meth)acrylic acid can be mixed and used as an ultraviolet curable resin. Furthermore, fillers, colorants, flame retardants, and plasticizers that do not reduce the adhesiveness and light transmittance of the bind tape may be mixed with the ultraviolet curable resin. The phenoxy resin used in the present invention has the general formula The molecular weight is preferably 10,000 to 50,000. Also, 20 parts by weight for 100 parts by weight of ultraviolet curable resin.
It is preferable to use from 50 parts by weight. When mixed with an ultraviolet curable resin, the phenoxy resin imparts uncured fiber bonding strength and appropriate adhesiveness to the tape. If the phenoxy resin is less than 20 parts by weight, the adhesion between the tape layers will deteriorate, and
Adding winding tension makes it easier to break. but,
If the amount is more than 50 parts by weight, the resin component becomes brittle and the glass fibers may break during winding. The ultraviolet curable bind tape according to the present invention includes:
After adding appropriate photosensitizers, solvents, etc. to the mixture of the vinyl ester and phenoxy resin and applying or impregnating it onto glass fibers with a brush or roller,
It is made by removing the solvent by drying. The tape after solvent drying has moderate tackiness. The amount of the resin component applied to the glass fibers is preferably 20 to 30 parts by weight per 100 parts by weight of the glass fibers. The ultraviolet curable bind tape according to the present invention includes:
Normal winding tension (7 to 15 kg per 1 mm of tape width)
The tape does not break even when added, and the adhesion between the layers is good even when thickly wound, and each layer is cured as one, down to the bottom layer, by irradiation with ultraviolet rays, so the tape has great strength after curing, and is heat resistant and oil resistant. It has excellent properties and is extremely useful as a tightening member for bind-wound laminated cores or wire windings. The present invention will be explained in more detail below with reference to Examples and Comparative Examples. In addition, in the examples and comparative examples, the following table -
The characteristic values shown in 1 were determined by the following test method: Bonding strength: Cut the uncured bind tape to a length of 50 mm, narrow it with chucks parallel to the fibers, and set the gap between the chucks to 20 mm in the transverse direction of the tape. The chuck was pulled at a moving speed of 10 mm/min, and the maximum strength until the resin bond between the fibers broke and separated, and the elongation when the fibers separated were determined. Tensile strength after curing: Measured by the ring method according to JIS2412. The ring test fitting is split type and has an inner diameter.
It is 156mm and the tape winding width is 19mm. Tensile samples were prepared with a tape width of 19 mm and a winding tension of 130 mm.
Kg was wrapped around the metal fitting three or six times, and then the test metal fitting was irradiated with ultraviolet rays while rotating and cured. For the tensile test, each divided piece was
The tensile strength was defined as the tensile strength at breakage at a rate of mm/min. In a tensile test in the transverse direction of this tape, when the strength of separation between fibers and the elongation when fibers separate are expressed as bonding force, it was found that there is a relationship between bonding force and breakage due to winding tension. In other words, a tape with a high bond strength will not break even when a winding tension is applied. Examples and Comparative Examples The middle part refers to parts by weight. Examples 1 to 4 100 parts of vinyl ester synthesized from Epicote 828 (epoxy resin, trade name of Ciel Corporation) and methacrylic acid, 20 parts of BAKELITE (phenoxy resin, trade name of Union Carbide Corporation) (Example 1), 30 parts
(Example 2), 40 parts (Example 3), and 50 parts (Example 4), added 1 part of benzoin isobutyl ether as a photosensitizer, and added toluene/MEK (70 parts).
parts/30 parts) A resin mixture made with a mixed solvent to a viscosity (room temperature) of 1000 cp or less is applied to the unidirectionally aligned yarn (ELG1502/290 pieces) with a roller so that the resin adhesion is 24-26% and the tape width is 30 mm. , and dried with hot air at 100°C for 5 minutes to obtain an ultraviolet curable bind tape. The tapes obtained in Examples 1 to 4 did not break even when they were wound around a laminated iron core having irregularities under tension (7 to 15 kg per tape width). Table 1 shows the bond strength of these tapes and the tensile strength after curing with 3 or 6 turns. Example 5 100 parts of vinyl ester synthesized from Epikote 1001 (epoxy resin, trade name of Ciel Co., Ltd.) and methacrylic acid and 30 parts of BAKELITE (phenoxy resin) were mixed and treated in the same manner as in Example 1 to obtain an ultraviolet curing type. Obtained binding tape. The bond strength and tensile strength after curing of this tape are shown in Table 1 below. This tape did not break even when winding tension was applied. Example 6 A resin prepared by mixing 100 parts of vinyl ester synthesized from DEN438 (epoxy resin, trade name of Dow Chemical Company) and methacrylic acid, and 30 parts of BAKELITE (phenoxy resin) was treated in the same manner as in Example 1 and cured with ultraviolet light. Obtained mold binding tape. The bond strength and tensile strength after curing of this tape are shown in Table 1 below. This tape did not break even when winding tension was applied. Example 7 100 parts of vinyl ester synthesized from Epicote 828 and methacrylic acid and 20 parts of BAKELITE (phenoxy resin) were mixed, 2 parts of benzoin isobutyl ether was added, and toluene/MEK (70 parts/30 parts) was mixed.
part) Width made with a mixed solvent to a viscosity of 1000 cp or less
A 19 mm glass cloth was impregnated with resin to a coating amount of 24 to 26% to obtain an ultraviolet curable bind tape. Table 1 shows the tensile strength of this tape after curing. Comparative Example 1 One part of benzoin butyl ether was added only to the vinyl ester synthesized from Epicote 828 and methacrylic acid, and treated in the same manner as in Example 1 to obtain an ultraviolet curable bind tape. Table 1 shows the tensile strength of this tape after curing. This tape broke when winding tension was applied. Further, the tensile strength after curing becomes lower when the film is rolled thickly. 【table】

Claims (1)

[Claims] 1. Consists of a resin component that is a mixture of an ultraviolet curable resin, which is a vinyl ester synthesized from an epoxy resin and (meth)acrylic acid, and a phenoxy resin, and glass cloth and glass yarn with no folded wefts. An ultraviolet curing bind tape characterized by being made of glass fiber selected from the group. 2. The ultraviolet curable bind tape according to claim 1, comprising a resin component in which 20 to 50 parts by weight of a phenoxy resin is mixed with 100 parts by weight of an ultraviolet curable resin and glass fibers.