AU614843B2 - Laminated structure with low dielectric losses - Google Patents

Laminated structure with low dielectric losses Download PDF

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Publication number
AU614843B2
AU614843B2 AU35688/89A AU3568889A AU614843B2 AU 614843 B2 AU614843 B2 AU 614843B2 AU 35688/89 A AU35688/89 A AU 35688/89A AU 3568889 A AU3568889 A AU 3568889A AU 614843 B2 AU614843 B2 AU 614843B2
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AU
Australia
Prior art keywords
fibres
process according
paper
layers
layer
Prior art date
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AU35688/89A
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AU3568889A (en
Inventor
Jan-Fredrik Jansson
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JANSSON JAN F
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JANSSON JAN F
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Application filed by JANSSON JAN F filed Critical JANSSON JAN F
Publication of AU3568889A publication Critical patent/AU3568889A/en
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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B29/00—Layered products comprising a layer of paper or cardboard
    • B32B29/02—Layered products comprising a layer of paper or cardboard next to a fibrous or filamentary layer
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B27/00—Layered products comprising a layer of synthetic resin
    • B32B27/02—Layered products comprising a layer of synthetic resin in the form of fibres or filaments
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B27/00—Layered products comprising a layer of synthetic resin
    • B32B27/04—Layered products comprising a layer of synthetic resin as impregnant, bonding, or embedding substance
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B27/00—Layered products comprising a layer of synthetic resin
    • B32B27/06—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material
    • B32B27/10—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material of paper or cardboard
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B27/00—Layered products comprising a layer of synthetic resin
    • B32B27/32—Layered products comprising a layer of synthetic resin comprising polyolefins
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B5/00—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts
    • B32B5/02—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by structural features of a fibrous or filamentary layer
    • B32B5/08—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by structural features of a fibrous or filamentary layer the fibres or filaments of a layer being of different substances, e.g. conjugate fibres, mixture of different fibres
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B5/00—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts
    • B32B5/22—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed
    • B32B5/24—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed one layer being a fibrous or filamentary layer
    • B32B5/26—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed one layer being a fibrous or filamentary layer another layer next to it also being fibrous or filamentary
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B5/00—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts
    • B32B5/22—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed
    • B32B5/24—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed one layer being a fibrous or filamentary layer
    • B32B5/28—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed one layer being a fibrous or filamentary layer impregnated with or embedded in a plastic substance
    • D—TEXTILES; PAPER
    • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
    • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
    • D04H13/00—Other non-woven fabrics
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B3/00—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties
    • H01B3/18—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances
    • H01B3/48—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances fibrous materials
    • H01B3/52—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances fibrous materials wood; paper; press board
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2262/00—Composition or structural features of fibres which form a fibrous or filamentary layer or are present as additives
    • B32B2262/02—Synthetic macromolecular fibres
    • B32B2262/0253—Polyolefin fibres
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2323/00—Polyalkenes
    • B32B2323/04—Polyethylene

Landscapes

  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Wood Science & Technology (AREA)
  • Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Textile Engineering (AREA)
  • Laminated Bodies (AREA)
  • Paper (AREA)
  • Multicomponent Fibers (AREA)
  • Organic Insulating Materials (AREA)

Description

OPI DATE 29/11/89 APPLN- ID 35688 89 AOJP DATE 04/01/90 PCT NUMBER PCT/SE89/00251
PCT
INTERNATIONAL APPLICATIO ?BL H R HP t T COOPERATION TREATY (PCT) (51) International Patent Classification 4 (11) international Publication Number: WO 89/11151 HOiB 3/48 A (43) International Publication Date: 16 November 1989 (16.11,89) (21) International Application Number: PCT/SE89'00251 SE (European patent), US.
(22) International Filing Date: 3 May 1989 (03.05.89) Published With international search report.
Priority data: In English translation (filed in Swedish.
8801668-8 3 May 1988 (03.05.88) SE (71X72) Applicant and Inventor: JANSSON, Jan-Fredrik [SE/ SE]; Heimdalsvagen 8, S-184 51 Ostersk'r (SE).
(74) Agents: HALLDIN, Bo et al.; Dr. Ludwig Brann PatentbyrA AB, P.O. Box 7524, S-103 92 Stockholm (SE).
(81) Designated States: AT (European patent), AU, BE (European patent), BR, CH (European patent), DE (European patent), DK, FI, FR (European patent), GB (European patent), IT (European patent), JP, KR, LU (European patent), NL (European patent), NO, (54) Title: LAMINATED STRUCTURE WITH LOW DIELECTRIC LOSSES (57) Abstract The present invention relates to a laminated structure with low dielectric losses, which structure is characterized in that it comprises two or more layers of cellulose fibre paper separated by spacing layers comprising fibres which by adhesion to one another by means of a suitable surface lay',r on said fibres of a material which melts at lower temperature than the fibres, form a lattice structure with a fibre content of less than 30 percent by volume.
WO 89/11151 PCr/SE89/00251 1 1 Laminated structure with low dielectric losses Coarse cables are today insulated with oil impregnated, socalled cable paper, where the cable paper i.a. serves as a carrier of the oil insulation. Cable paper is found partly in the form of cellulose fibre paper, partly in combinations of cellulose fibre, polyolefin fibre and/or film of polyolefins.
The purpose of the polyolefin additives, which have lower dielectric losses than cellulose, is to lower the total dielectric losses of the construction by "diluting".
SE-B-7705609-1 describes a laminated structure in which a PP-non-woven material is laminated together with paper by pressing at temperatures at which the PP-fibres partly melt to cause bonding on one hand between the PP-fibres and on the other hand between the PP-fibres and the paper fibres. If the temperature is too low no bonding is achieved. If the temperature is too high the fibres melt and the non-woven material is destroyed. The temperature range which must be applied to achieve bonding but not melting of the PP-fibres is very limited and causes problems in industrial production.
The present invention relates to a laminated structure comprising two or more layers of cellulose fibre paper separated by spacing layers (non-woven) built upp of fibres which by Ssuitable adhesion to one another form a lattice structure with a fibre content of less than 30 percent by volume. By means of said adhesion one can achieve the same stability, i.e.
mechanical strength, thickness tolerances etc. previously achieved with non-bonded fibres with a fibre content of over percent by volume.
WO89/11151 PCT/SE89/00251 2 The laminates produced have dielectric losses which closely follow the mixing rule, i.e.
dYtp d d p p p n wherein d represents the dielectric losses, t represents the total thickness of the layer types used and indexes i, p and n represent laminate, paper and non-woven, respectively.
Since the dielectric losses of the non-woven material are much lower than those of the paper the dielectic losses are reduced approximately proportionally to the reduced amount of paper used. This means, for example, that with a thickness of the layers: paper: 40 pm, non-woven: 100 pm, paper 40 pm, the laminate has dielectric losses of approx. 0.5 of the dielectric losses of a cable paper of the same thickness produced entirely of the same paper.
The lattice fibre structure is built up of fibres with a sheath of, or in another way applied suitable polymer which melts at temperatures lower than the fibres. The sheath can either be continuous and completely surround the fibre core or cover it partially. This sheath can be produced by fibre spinning through a double extruder.
By heating a "non-woven"-structure of this fibre to temperatures at which the low melting sheath sticks and simultaneously compressing the non-woven structure and maintaining it pressed together until the temperature has lowered so that the sheathing material has stiffened, the sheathing material at those points where two fibres are pressed against each other serve as joining points whereby a lattice structure with good dimension stability even at relatively low fibre contents is formed.. An example of this type of fibre is ES-fibre from Danaklon A/S, which on heating to 1200 C, compressing and cooling to 800 C forms the required structure, cf. the drawing.
7 WO 89/11151 PCT/SE89/00251 The lattice structure can alternatively be obtained by providing the joints between the fibres which are not melted at the heating, compression and cooling, by means of the addition of a suitable binding agent which melts at a lower temperature than the fibres. The additive may be supplied in the form of fibres or film of suitable polymer, which melts at a lower temperature than the fibres forming the spacing layer, whereby on heating to the melting point of the additive this melts and creates the joints.
Examples of suitable material for the construction are, for example, different types of polyolefins, polypropylene-fibres (PP-fibre) with polyethylene (PE) or a suitable olefin copolymer with lower melting point than polypropylene as a "binding agent".
The invention is illustrated by means of the following comparative examples which, however, are not meant to limit the scope of the invention in any way but are only intended to illustrate it.
i Example 1 CABLE PAPER LAMINATE BUILT UP OF CABLE PAPER AND NON-WOVEN I LAYERS OF PP-FIBRE WITH A SHEATH OF PE i Laminates were produced by compressing normal cable paper and non-woven of polypropylene fibre (PP-fibre) with a sheath of polyethylene (PE).
Before compression the non-woven material was washed for removal of any optional substances added during its manufacture.
Laminates were produced having different thicknesses: 120-400 Vm by combining cable paper and non-woven layers having different thicknesses.
F 4 WO 89/11151 PCT/SE89/00251
I
1 4 All the laminates consisted of three layers: cable paper I non-woven cable paper. The outer layer of the cable paper H was chosen to provide a surface with the same properties as those of normal cable paper. The thickness of the paper I layers and the non-woven layers was chosen in relation to the thickness of commercially available cable paper.
The laminates were produced by pressing at temperatures above the melting point of the surface layer but below that of the PP-fibres, for example between 130-150 0 C and at a pressure of i between 0.1-5 MPa.
The dielectric losses of the laminate followed the same formula as stated above.
Example 2 CABLE PAPER LAMINATE BUILT UP OF CABLE PAPER AND LAYERS OF NON-WOVEN OF PP-FIBRES WITH PE-FILM AS BINDING AGENT i Laminates were produced by pressing at the same temperature and pressure as in example 1 but with a non-woven layer comprising PP-fibre only. The bonding, n one hand between the i PP-fibres and on the other hand between the PP-fibres and the i paper fibres, was achieved by placing a thin PE-film on one jhand between PP-fibre layers and on the other hand between i the outer PP-fibre layers and the paper layers and by melting at the compression.
The construction of the laminates was cable paper thin PE-film (PP-non-woven/thin PE-film/PP-non-woven)m thin PE-film/-cable paper.
m represents the number of layers laminated in between the cable paper layers. Surfaces of normal cable paper were used to give the laminate the same surface properties as those of normal cable paper.
WO 89/11151 PCT/SE89/00251 For the thinner laminates m=l was chosen, for the thicker laminates 1< m Laminates with thicknesses between 100 and 400 pm were produced.
The thickness of the PE-films was 4 20 pm and did not add to the thickness of the laminate because they melted under the compression.
The dielectric losses of the laminate followed the same formula as previously stated.
Example 3 CABLE PAPER LAMINATE BUILT UP OF CABLE PAPER AND NON-WOVEN LAYERS OF PP-FIBRES AND PE-FIBRES Laminates were produced in the same way as in example 2 but the PE-film was replaced by PE-fibres which either were placed Sbetween the different layers in the laminate or mixed in among the PP-fibres in the non-woven material.
The dielectric losses of the laminate followed the same approximate formula as previously stated.

Claims (4)

  1. 2. A process according to claim 1, c h a r a c t e r i z e d in that the surface layer comprises a sheath surrounding the fibres which form the spacing layer.
  2. 3. A process according to claim 1, c h a r a c t e r i z e d in that the surface layer is produced by means of a film of polymeric material placed between layers of fibres of which the spacing layer(s) is(are) built up whereafter the film is melted by heating to the melting point of the film material. ii 4. A process according to claim i, c h a r a c t e r i z e d in that the surface layer on the fibres which form the spacing layer is provided by means of fibres of polymeric material mixed in among the fibres of the spacing layer whereafter the mixed in fibres are melted by heating to their melting point. A process according to ,-laim 1, c h a r a c t e r i z e d in that the surface layer on the fibres forming the spacing layer is provided by means of -C1* SUPSTITUTh S"-ET 2 1 7 point than the fibres of the spacing layer, which are alternately layered with layers of spacing fibres, whereafter the lower melting fibres are melted by heating to their melting point. t 6. A process according to any of the previous claims, I c h a r a c t e r i z e d in that the spacing layer is i comprised of polypropylene fibres.
  3. 7. A process according to any of the previous claims, Sc h a r a c t e r i z e d in that the material forming the surface layer on the fibres of the spacing layer consists of polyethylene. i
  4. 8. A process according to any of claims 1-6, c h a r a c t e r i z e d in that the material forming the surface layer on the fibres of the spacing layer consists of an olefin copolymer with lower melting point than poly- propylene. i 'i -i SURSTITUTE St,-"_EET
AU35688/89A 1988-05-03 1989-05-03 Laminated structure with low dielectric losses Ceased AU614843B2 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE8801668 1988-05-03
SE8801668A SE8801668D0 (en) 1988-05-03 1988-05-03 CABLE PAPERS WITH LOW DIELECTRIC LOSSES

Publications (2)

Publication Number Publication Date
AU3568889A AU3568889A (en) 1989-11-29
AU614843B2 true AU614843B2 (en) 1991-09-12

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
AU35688/89A Ceased AU614843B2 (en) 1988-05-03 1989-05-03 Laminated structure with low dielectric losses

Country Status (7)

Country Link
EP (1) EP0426685A1 (en)
JP (1) JPH03505019A (en)
AU (1) AU614843B2 (en)
DK (1) DK260590A (en)
FI (1) FI905386A0 (en)
SE (1) SE8801668D0 (en)
WO (1) WO1989011151A1 (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA2087999A1 (en) * 1992-09-23 1994-03-24 Lee K. Jameson Hydrosonically bonded nonwoven/paper material and process for forming the same
US9437348B2 (en) * 2010-12-17 2016-09-06 3M Innovative Properties Company Electrical insulation material
WO2013187956A1 (en) 2012-06-15 2013-12-19 3M Innovative Properties Company Electrical insulation material

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE427592B (en) * 1976-05-14 1983-04-18 Dainichi Nippon Cables Ltd LAMINATED ELISOLATION MATERIAL FOR USE IN OIL IMPROVED CONDITION

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE427592B (en) * 1976-05-14 1983-04-18 Dainichi Nippon Cables Ltd LAMINATED ELISOLATION MATERIAL FOR USE IN OIL IMPROVED CONDITION

Also Published As

Publication number Publication date
DK260590D0 (en) 1990-10-30
WO1989011151A1 (en) 1989-11-16
DK260590A (en) 1990-10-30
SE8801668D0 (en) 1988-05-03
AU3568889A (en) 1989-11-29
JPH03505019A (en) 1991-10-31
EP0426685A1 (en) 1991-05-15
FI905386A0 (en) 1990-10-31

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