GB2044128A - Reinforced cement sheets - Google Patents

Reinforced cement sheets Download PDF

Info

Publication number
GB2044128A
GB2044128A GB7909153A GB7909153A GB2044128A GB 2044128 A GB2044128 A GB 2044128A GB 7909153 A GB7909153 A GB 7909153A GB 7909153 A GB7909153 A GB 7909153A GB 2044128 A GB2044128 A GB 2044128A
Authority
GB
United Kingdom
Prior art keywords
film
treatment
cement
plastics
fibrillated
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
GB7909153A
Other versions
GB2044128B (en
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Dow Mac Concrete Ltd
Original Assignee
Dow Mac Concrete Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Dow Mac Concrete Ltd filed Critical Dow Mac Concrete Ltd
Priority to GB7909153A priority Critical patent/GB2044128B/en
Publication of GB2044128A publication Critical patent/GB2044128A/en
Application granted granted Critical
Publication of GB2044128B publication Critical patent/GB2044128B/en
Expired legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B16/00—Use of organic materials as fillers, e.g. pigments, for mortars, concrete or artificial stone; Treatment of organic materials specially adapted to enhance their filling properties in mortars, concrete or artificial stone
    • C04B16/04—Macromolecular compounds
    • C04B16/06—Macromolecular compounds fibrous
    • C04B16/0608—Fibrilles, e.g. fibrillated films
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B28—WORKING CEMENT, CLAY, OR STONE
    • B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
    • B28B23/00—Arrangements specially adapted for the production of shaped articles with elements wholly or partly embedded in the moulding material; Production of reinforced objects
    • B28B23/0006—Arrangements specially adapted for the production of shaped articles with elements wholly or partly embedded in the moulding material; Production of reinforced objects the reinforcement consisting of aligned, non-metal reinforcing elements
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C59/00—Surface shaping of articles, e.g. embossing; Apparatus therefor
    • B29C59/10—Surface shaping of articles, e.g. embossing; Apparatus therefor by electric discharge treatment
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29D—PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
    • B29D28/00—Producing nets or the like, e.g. meshes, lattices
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
    • B29K2105/00—Condition, form or state of moulded material or of the material to be shaped
    • B29K2105/25—Solid

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Ceramic Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Chemical Or Physical Treatment Of Fibers (AREA)
  • Laminated Bodies (AREA)
  • Shaping By String And By Release Of Stress In Plastics And The Like (AREA)

Abstract

Cement sheets are reinforced by fibrillated plastics, e.g. polypropylene or polyethylene film, which has been subjected to a spark discharge treatment (E-treatment). The film is first drawn (2) and fibrillated by a pin wheel (3) before subjected to high voltage high frequency sparks from electrodes (4). The film is subsequently laterally stretched (5) to form a net and then incorporated with cement. <IMAGE>

Description

SPECIFICATION Reinforced cement sheets This invention relates to cement sheets of the kind comprising layers of fibrillated polypropylene or other plastics net or short lengths of polypropylene or other plastics fibres in a cementitious matrix.
For many years the surface treatment of plastics materials by electric radiation or corona discharge, commonly known as E-treatment, has been used to improve the receptivity of the materials to inks, laquers, and other organic substances. We have now found that such treatment applied to fibrillated plastics reinforcement materials in cement sheets provides a surprising improvement in the bond between such materials and the cement.
In accordance with the invention therefore the plastics material is subjected to an electrical radiation treatment of the kind commonly known as E-treatment prior to incorporation in the sheets.
An embodiment of the invention will now be described with reference to the accompanying drawing which shows diagrammatically the steps of the process of the invention.
Polypropylene film is extruded into a water bath 1 and fed to a drawing machine 2 in which the film is subjected to longitudinal stretching so as to orient the polymer chains along the length of the film.
Following the stretching process, the film is fibrillated by being passed over a pin wheel 3 which produces longitudinal slits in the film which thus is given the characteristics of a fibrous tape. The film is then fed through E-treatment equipment 4 in which it is subjected to a high voltage, high frequency electric discharge from electrodes between which the film passes. Typical values for the treatment are frequencies of 20 KHz to 30KHz and voltages 15KV to 25KV. This treatment causes bombardment of the film by spark discharges which penetrates the surface of the film.
Atthe next stage, the film is fed through a mesh spreader 5 which extends the film transversely so that it forms a mesh or net of polypropylene fibres.
The mesh or net so produced is then fed forward to the known final stages of reinforced cement sheet manufacture at which, for example, it is coated with a cement mix and lengths of the coated mesh or net are laminated and the cement is allowed or caused to set and harden.
In a variation of this process, the film is subjected to the E-treatment before it is fibrillated.
1. A method of making cement sheets reinforced with fibrillated plastics film comprising the step of subjecting the film to a high voltage, high frequency spark discharge treatment before it is incorporated with the cement mix.
2. A method according to claim 1, wherein the film is drawn longitudinally and slit to produce a fibrous sheet structure before being subjected to the spark discharge treatment.
3. A method according to claim 1 or 2, wherein the film is stretched laterally of the direction of its fibres after being subjected to the spark discharge treatment.
4. A method of making cement sheets reinforced with fibrillated plastics film substantially as hereinbefore described with reference to the accompanying drawings.
5. Reinforced cement sheets whenever made by a method according to any of the preceding claims.
**WARNING** end of DESC field may overlap start of CLMS **.

Claims (5)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Reinforced cement sheets This invention relates to cement sheets of the kind comprising layers of fibrillated polypropylene or other plastics net or short lengths of polypropylene or other plastics fibres in a cementitious matrix. For many years the surface treatment of plastics materials by electric radiation or corona discharge, commonly known as E-treatment, has been used to improve the receptivity of the materials to inks, laquers, and other organic substances. We have now found that such treatment applied to fibrillated plastics reinforcement materials in cement sheets provides a surprising improvement in the bond between such materials and the cement. In accordance with the invention therefore the plastics material is subjected to an electrical radiation treatment of the kind commonly known as E-treatment prior to incorporation in the sheets. An embodiment of the invention will now be described with reference to the accompanying drawing which shows diagrammatically the steps of the process of the invention. Polypropylene film is extruded into a water bath 1 and fed to a drawing machine 2 in which the film is subjected to longitudinal stretching so as to orient the polymer chains along the length of the film. Following the stretching process, the film is fibrillated by being passed over a pin wheel 3 which produces longitudinal slits in the film which thus is given the characteristics of a fibrous tape. The film is then fed through E-treatment equipment 4 in which it is subjected to a high voltage, high frequency electric discharge from electrodes between which the film passes. Typical values for the treatment are frequencies of 20 KHz to 30KHz and voltages 15KV to 25KV. This treatment causes bombardment of the film by spark discharges which penetrates the surface of the film. Atthe next stage, the film is fed through a mesh spreader 5 which extends the film transversely so that it forms a mesh or net of polypropylene fibres. The mesh or net so produced is then fed forward to the known final stages of reinforced cement sheet manufacture at which, for example, it is coated with a cement mix and lengths of the coated mesh or net are laminated and the cement is allowed or caused to set and harden. In a variation of this process, the film is subjected to the E-treatment before it is fibrillated. CLAIMS
1. A method of making cement sheets reinforced with fibrillated plastics film comprising the step of subjecting the film to a high voltage, high frequency spark discharge treatment before it is incorporated with the cement mix.
2. A method according to claim 1, wherein the film is drawn longitudinally and slit to produce a fibrous sheet structure before being subjected to the spark discharge treatment.
3. A method according to claim 1 or 2, wherein the film is stretched laterally of the direction of its fibres after being subjected to the spark discharge treatment.
4. A method of making cement sheets reinforced with fibrillated plastics film substantially as hereinbefore described with reference to the accompanying drawings.
5. Reinforced cement sheets whenever made by a method according to any of the preceding claims.
GB7909153A 1979-03-15 1979-03-15 Reinforced cement sheets Expired GB2044128B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB7909153A GB2044128B (en) 1979-03-15 1979-03-15 Reinforced cement sheets

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB7909153A GB2044128B (en) 1979-03-15 1979-03-15 Reinforced cement sheets

Publications (2)

Publication Number Publication Date
GB2044128A true GB2044128A (en) 1980-10-15
GB2044128B GB2044128B (en) 1983-01-26

Family

ID=10503900

Family Applications (1)

Application Number Title Priority Date Filing Date
GB7909153A Expired GB2044128B (en) 1979-03-15 1979-03-15 Reinforced cement sheets

Country Status (1)

Country Link
GB (1) GB2044128B (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0248776A2 (en) * 1986-05-22 1987-12-09 Hans-Erik Gram Sheet-like products or molded products reinforced with an expanded material

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0248776A2 (en) * 1986-05-22 1987-12-09 Hans-Erik Gram Sheet-like products or molded products reinforced with an expanded material
EP0248776A3 (en) * 1986-05-22 1989-06-07 Hans-Erik Gram Sheet-like products or molded products reinforced with an expanded material

Also Published As

Publication number Publication date
GB2044128B (en) 1983-01-26

Similar Documents

Publication Publication Date Title
DE4343027B4 (en) Gas barrier rubber laminate and process for its preparation
EP0090062B1 (en) Process and apparatus for the manufacture of electret filaments, fibres or the like
DE2942298C2 (en) Process for the production of a rough polypropylene electrical insulation film
GB2026379A (en) Reinforcing fibres and method of producing same
EP0280103B1 (en) Process for the coating of printing cylinders or cores with a continuous jointless photosensitive layer, and their use in the production of printing forms for rotoprinting
DE2362915B2 (en) Corona discharge electrode for generating a negative corona discharge
DE1504741A1 (en) Method and device for the electrical discharge treatment of foils
EP0073427B2 (en) Process and apparatus for the pretreatment of polymer base materials
DE3105138A1 (en) METHOD FOR PRODUCING A HIGH VOLTAGE IGNITION CABLE WITH LOW ELECTROSTATIC CAPACITY
US2303341A (en) Method and apparatus for heating and vulcanizing rubber and similar matter
DE2550664C3 (en) Process for the production of a hose carrying pressure fluid
DE1629569B1 (en) Process to improve the quality of a polyamide film
GB2044128A (en) Reinforced cement sheets
DE3103211A1 (en) HIGH VOLTAGE IGNITION CABLES
EP0870595A2 (en) Process for manufacturing a preform for vehicle tyres
EP0277552A2 (en) Sheet-like or cap-like mask for paint work on motor vehicles or parts thereof
US1646825A (en) Fibrous article and method for producing such article
EP0598195B1 (en) Method and apparatus for treating a yarn-like product
EP0132219A1 (en) Anti-corrosively coated pipe with a mechanical insulating layer
DE3341415C2 (en) Process for discharging electrostatically charged, insulating surfaces
EP0588246B1 (en) Method and apparatus for treatment of endless webs
AT330936B (en) PROCESS FOR THE MANUFACTURING OF FILMS FROM POLYMERIC MATERIALS FURTHER PROCESSABLE INTO SPLIT FIBERS WITH LATENT CRIMPING
DE2101921A1 (en) Process for the production of insulated high voltage cables
DE102020124168B4 (en) Method and device for spreading a fiber bundle
DE1222241B (en) Process for treating the surfaces of metal foils

Legal Events

Date Code Title Description
PCNP Patent ceased through non-payment of renewal fee