Electrical insulation material and transformer

Patent metadata

Field	Value
Publication number	US-2016343465-A1
Application number	US-201515113943-A
Country	US
Kind code	A1
Filing date	Jan 27, 2015
Priority date	Jan 27, 2014
Publication date	Nov 24, 2016
Grant date	—

Abstract

An article comprises an inorganic filler, fully hydrolyzed polyvinyl alcohol fibers, a polymer binder, and high surface area fibers. The article can be formed as an electrically insulating paper for electrical equipment, such as a liquid filled transformer, which can thereby be substantially cellulose free.

First claim

1 . An article comprising:
an inorganic filler; fully hydrolyzed polyvinyl alcohol fibers; a polymer binder; and high surface area fibers.

2 . The article of claim 1 formed as a nonwoven paper.

3 . The article of claim 1 wherein the inorganic filler comprises at least one of kaolin clay, talc, mica, calcium carbonate, silica, alumina, alumina trihydrate, montmorillonite, smectite, bentonite, illite, chlorite, sepiolite, attapulgite, halloysite, vermiculite, laponite, rectorite, perlite, aluminum nitride, silicon carbide, boron nitride, and combinations thereof.

4 . The article of claim 3 wherein inorganic filler comprises kaolin clay.

5 . The article of claim 4 wherein the kaolin clay comprises at least one of water-washed kaolin clay, delaminated kaolin clay, calcined kaolin clay, and surface-treated kaolin clay.

6 . The article of claim 1 , wherein the polymer binder comprises a latex-based material.

7 . The article of claim 1 , wherein the polymer binder comprises at least one of acrylic, nitrile, and styrene acrylic latex.

8 . The article of claim 1 , wherein the high surface area fibers comprise glass microfiber.

9 . The article of claim 1 comprising from about 3% to about 20% fully hydrolyzed polyvinyl alcohol fibers, wherein the percentages are by weight.

10 . The article of claim 9 , comprising:
from about 50% to about 85% kaolin clay; from about 7% to about 25% polymer binder; and from about 2% to about 10% glass microfiber, wherein the percentages are by weight.

11 . The article of claim 1 , wherein the article is substantially cellulose free.

12 . The article of claim 1 wherein the article is non-hygroscopic.

13 . An insulation system for electrical equipment, wherein the insulation system comprises the article of claim 1 .

14 . The insulation system of claim 13 , wherein the electrical equipment comprises one of a transformer, a motor, and a generator.

15 . The insulation system of claim 13 , wherein the electrical equipment comprises a liquid filled transformer.

16 . An oil filled transformer comprising electrically insulating paper having fully hydrolyzed polyvinyl alcohol fibers.

17 . The oil filled transformer of claim 16 , wherein the electrically insulating paper further comprises an inorganic filler, a polymer binder, and glass microfibers.

18 . The oil filled transformer of claim 17 , wherein the electrically insulating paper further comprises about 3% to about 20% fully hydrolyzed polyvinyl alcohol fibers, from about 50% to about 85% kaolin clay, from about 7% to about 25% polymer binder, and from about 2% to about 10% glass microfiber, wherein the percentages are by weight.

19 . The oil filled transformer of claim 16 , wherein the electrically insulating paper is substantially cellulose free.

Assignees

• 3M Innovative Properties Co

Inventors

• Turpin Robert H
• Browning Rhesa M
• Mahoney David V
• Huang Mitchell T
• Stankes David S
• Fox Martin H

Classifications

• D21H13/40

  vitreous, e.g. mineral wool, glass fibres · CPC title

• H01F27/2876

  Cooling (cooling transformers and inductances in general H01F27/08) · CPC title

• H01B3/47

  fibre-reinforced plastics, e.g. glass-reinforced plastics · CPC title

• H01F27/327

  Encapsulating or impregnating (encapsulating coil and core H01F27/022) · CPC title

• D21H13/16

  Polyalkenylalcohols; Polyalkenylethers; Polyalkenylesters · CPC title