JPS6079083A - Adhesive tape - Google Patents

Abstract

PURPOSE:To provide an adhesive tape having a high curing rate and excellent flexibility, prepd. by applying a resin compsn. consisting of epoxy resin, butyral resin, polyamide resin and hardener, to a base tape, followed by drying. CONSTITUTION:40-200pts.wt. polyamide resin having a structural unit of the formula (where n is 10-11) and 0.2-10pts.wt. hardener (e.g. ethylmethylimidazol) are added to 100pts.wt. resin comprising a mixture of 40-60wt% resin and 60-40wt% buryral resin, and the mixture is dissolved in an org. solvent (e.g. cresol). The resultant org. soln. is applied to a base tape in an amt. of 20-50g/ m<2> (by solid), followed by drying under conditions not causing curing of the adhesive.

Description

[Detailed description of the invention] do.

Conventionally, as insulated wires for generators, glass winding wires in which a glass thread is wound around a conductor have mainly been used.

However, from the viewpoint of Space 7 Actor and dielectric strength, adhesives were applied to one side of aromatic polyamide paper tapes, tapes containing aromatic polyamide paper as part of the base material, mica paper mixed paper, etc. Tape winding in which adhesive tape is attached vertically to a conductor is being considered.

The tape winding described above has a higher breakdown voltage per insulating layer thickness than a glass winding, and when used as a coil, the coil can be made compact. Furthermore, since the adhesive tape is applied vertically, the amount of adhesive tape material consumed can be reduced compared to when the adhesive tape is wound horizontally. However, when manufacturing such a tape winding,
Immediately after applying the A-stage adhesive to the preheated conductor, remove the insulating tape, or apply the adhesive in advance and dry it, then align the adhesive-coated surface of the B-stage tape, then heat and press it. The adhesive wraps around the conductor, but if the curing speed of the adhesive is slow, the tape may peel off between the tape and the conductor or between the tapes after heat-pressing. To prevent such problems,
There are methods such as increasing the heater temperature, lengthening the heater, and slowing down the linear speed, but all of these methods reduce production efficiency and
This will have an adverse effect on workability, etc.

The present inventors have solved the above-mentioned problems in manufacturing a tape winding in which an adhesive tape with a B-stage adhesive applied to one side of the tape is attached vertically to a conductor, and has applied the B-stage adhesive at high speed. As a result of extensive research in order to bond adhesive tape to conductors and obtain a tape winding with good flexibility, we found that epoxy resin and butyral resin were 40/60~6.
100 parts (parts by weight, same below) of resin mixed in the range of 0/40 (weight ratio, same below), general formula: % formula % (wherein n represents an integer from 10 to 11) The above-mentioned problems can be solved by using an adhesive tape obtained by coating a tape with an organic solvent solution of a resin composition consisting of 40 to 200 parts of a polyamide resin consisting of structural units of The present invention has been completed.

The epoxy resins used in the present invention are not particularly limited, and include Epikot 1001, Epicoat 1004, Epicoat 1007, and Epicoat 1009 (hereinafter, manufactured by Neru Kagaku Co., Ltd.) synthesized from Les, Ritoeva bisphenol A and shrimp chlorohydrin, and bisphenol A. Examples include bisphenol A type epoxy resins such as Epiclon 1010 and Epiclon 6010 (both manufactured by Dainippon Ink Chemical Industry Co., Ltd. 11) synthesized from β-methylepichlorohydrin, bisphenol Y type epoxy resins, novolak type epoxy resins, etc.

The butyral resin used in the present invention is not particularly limited, and examples include Denka Butyral $2000-L,
Denka Butyral #60 Hit-1, Denka Butyral #4
000-2 (hereinafter, manufactured by Denki Kagaku Kogyo ■), etc.

The mixing ratio of the epoxy resin and butyral resin is 40
AO to 60/40, preferably 45755 to 55A5. If the proportion of the epoxy resin is smaller than the above range, peeling will easily occur between the tapes when heated at 150°0 to 200°a after coil winding, and if it is larger than the above range, the adhesion speed between tapes and tape conductors will be slow. Become,
The production speed decreases, which is not preferable.

As the polyamide resin composed of the structural unit represented by the general formula: (wherein n is the same as above) used in the present invention, for example, Ny
Examples include polyamide resins with long alkylene groups such as lon 11 and nylon 12. n in the structural unit is an integer of 10 to 11; when n is less than 10, the melting point of the polyamide resin becomes high and the adhesiveness deteriorates, and when 1n exceeds 11, it becomes impossible to obtain it industrially.

The curing agent used in the present invention includes curing agents commonly used as curing agents for epoxy resins, such as imidazole curing agents such as ethylmethylimidazole or 2-methylimidazole, and amines such as diethylenetriamine, triethylenetetramine, and diazi/diphenylmethane. Amine complex curing agents such as boron trifluoride-monoethylamine, boron trifluoride-motumethylamine, boron trifluoride dimethylamine, hexahydrophthalic anhydride, methylnadic anhydride, chlorendic anhydride An acid anhydride curing agent such as an acid may be used.

The amount of doryamide resin blended is 40 to 200 parts, preferably 100 to 200 parts, per 100 parts of the mixture of epoxy resin and butyral resin. If the blending amount is less than 40 parts, peeling tends to occur between the tapes when heated at ISO 0 to 2oooO after coil winding, and if it exceeds 200 parts, the adhesion speed between tapes and tape conductors during molding is slow. This decreases the manufacturing speed, which is undesirable.

The source of the curing agent for 100 parts of the mixture of epoxy resin and butyral resin is imidazole, 7 tons, 0.2 to 10 parts of the amine complex curing agent, and 20 to 50 parts of the acid anhydride curing agent. It may be added within this range.

Other components may be added to the resin composition as necessary. Other components that may be added include, for example, phenol resin, melamine resin, etc., and the composition 100
The amount added per part is 10 parts or less, preferably 5 parts.
below.

There are no particular restrictions on the method for preparing the epoxy resin, butyral resin, polyamide resin, curing agent, and other components added as necessary. However, if a method that requires heating and mixing is adopted, this step It is preferable to add a curing agent after the completion of the curing process. The composition is applied to the tape in the form of an organic solvent solution and dried to produce the adhesive tape of the present invention. Therefore, dissolving the composition in an organic solvent and preparing it as a solution increases the production efficiency and the produced adhesive. This is preferable from the viewpoint of the performance of the adhesive tape.

The organic solvent used for the above purpose is not particularly limited as long as it dissolves epoxy resins, butyral resins, polyamide resins, curing agents, etc., and includes, for example, cresol, napht, )luene, quinolene, and cellosolve. can be lost. However, the aromatic amide paper tape used in the present invention, the tape containing aromatic polyamide paper as part of the base material, the tape made from mixed paper such as mica mixed paper,
Woven fabric tape, non-woven fabric tape, paper tape, or combination tape of film and these, etc. 20-2009
/m'', preferably 40 to 100 g/m 2 Cresol, naphtha, etc. are preferred from the viewpoint of ease of application to tape, drying properties, solubility of adhesive, etc.

As a method for applying the organic solvent solution to the tape, commonly used methods such as spray coating and roll-to-roll coating may be employed. After applying the solution to one side of the tape, the tape is heated under conditions such that the adhesive does not harden, e.g.
The adhesive tape is dried under conditions such as 0x15 to 60 minutes and replaced with adhesive tape. The amount of adhesive applied to the tape is 20 to sop/m2 in terms of solid content, preferably 25 to aoy/rn.
It is 2.

Next, the adhesive tape of the present invention will be explained based on Examples.

Examples 1 to 6 and Comparative Examples 1 to 4 20 in which the resin compositions shown in Table 1 were dissolved in cresol.
% (wt%, the same applies hereinafter) solution, and the solution was diluted with 2 n
il Nomex 410 (aromatic polyamide paper manufactured by DuPont) with a roll tool and rotated at 120°
A single-sided adhesive tape was produced by heating and drying it for 20 minutes. The butyral resin used was $5000-K manufactured by Denki Kagaku Kogyo ■, and the curing agent was boron trifluoride monoethylamine.

The resulting adhesive tape contained an adhesive composition with a solid content of 32
9/m” was applied.

The tape is 2-0mm x 5. Onm rectangular copper wire 2
After being aligned at a rate of 5 m/min, the wire was passed through a 300 qO11, 2 m heater, and was vertically attached to obtain a tape winding.

The adhesion speed of the adhesive tape was determined using the obtained tape winding in the following manner. Early adhesion, breakdown voltage (BD
V) (straight line), adhesion state after heating, and flexibility were measured.

The results are shown in Table 1.

(Early adhesion) When the tape was applied vertically at a linear speed of 25 m/min, the overlapped portion of the tape that did not open during winding was evaluated as good, and the tape that opened was evaluated as poor. For those that opened, the linear speed at which they did not open was measured by changing the linear speed, and the results were recorded in 0 in the early adhesion column of Table 1.

(BDV) Aluminum foil was wound around a linear tape winding over a length of 10 cm, and ilE was applied between the conductor and the aluminum foil to measure its withstand voltage.

(Adhesion state after heating) (a) In the case of a straight line: A straight tape winding is
The adhesive tape was left in a constant temperature bath for 6 hours, and the case where the adhesive tape did not peel off was judged as good, and the case where it peeled off was judged as poor.

(b) After bending: After bending 180° with a round rod of 10 times the diameter (in this case, 2Qmm) so that the overlapping part of the adhesive tape that exists in the flat size is on the inside, the adhesive tape is placed in a constant temperature oven at 200°C. The adhesive tape was left to stand for 6 hours, and the case where the adhesive tape did not peel off was judged as good, and the case where it peeled off was judged as poor.

(Flexibility) When a round bar is applied to the 7-ratwise or edge-wise tape winding and bent 180 degrees, the minimum round bar diameter is the thickness or width of the copper wire that does not cause tape fraying. It was measured as a magnification.

Claims (1)

[Claims] 1 The weight ratio of epoxy resin and butyral resin is 40/
100 parts by weight of a resin mixed in the range of 60 to 60/40, 40 to 200 parts by weight of a polyamide resin consisting of structural units represented by the general formula: (wherein n represents an integer of 10 to 11), and cured. An adhesive tape made by coating a tape with an organic solvent solution of a resin composition consisting of an agent and drying it.