Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L23/00—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers
  • C08L23/02—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers not modified by chemical after-treatment
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
  • C08K3/00—Use of inorganic substances as compounding ingredients
  • C08K3/01—Use of inorganic substances as compounding ingredients characterized by their specific function
  • C08K3/013—Fillers, pigments or reinforcing additives
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
  • C08K3/00—Use of inorganic substances as compounding ingredients
  • C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
  • C08K3/20—Oxides; Hydroxides
  • C08K3/22—Oxides; Hydroxides of metals
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
  • C08K3/00—Use of inorganic substances as compounding ingredients
  • C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
  • C08K3/24—Acids; Salts thereof
  • C08K3/26—Carbonates; Bicarbonates
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
  • C08K5/00—Use of organic ingredients
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L23/00—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers
  • C08L23/02—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers not modified by chemical after-treatment
  • C08L23/04—Homopolymers or copolymers of ethene
  • C08L23/06—Polyethene
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L23/00—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers
  • C08L23/02—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers not modified by chemical after-treatment
  • C08L23/04—Homopolymers or copolymers of ethene
  • C08L23/08—Copolymers of ethene
  • C08L23/0807—Copolymers of ethene with unsaturated hydrocarbons only containing four or more carbon atoms
  • C08L23/0815—Copolymers of ethene with unsaturated hydrocarbons only containing four or more carbon atoms with aliphatic 1-olefins containing one carbon-to-carbon double bond
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L25/00—Compositions of, homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an aromatic carbocyclic ring; Compositions of derivatives of such polymers
  • C08L25/02—Homopolymers or copolymers of hydrocarbons
  • C08L25/04—Homopolymers or copolymers of styrene
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L25/00—Compositions of, homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an aromatic carbocyclic ring; Compositions of derivatives of such polymers
  • C08L25/02—Homopolymers or copolymers of hydrocarbons
  • C08L25/04—Homopolymers or copolymers of styrene
  • C08L25/08—Copolymers of styrene
  • C08L25/10—Copolymers of styrene with conjugated dienes
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L9/00—Compositions of homopolymers or copolymers of conjugated diene hydrocarbons
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L91/00—Compositions of oils, fats or waxes; Compositions of derivatives thereof
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L2205/00—Polymer mixtures characterised by other features
  • C08L2205/03—Polymer mixtures characterised by other features containing three or more polymers in a blend
  • C08L2205/035—Polymer mixtures characterised by other features containing three or more polymers in a blend containing four or more polymers in a blend
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L2207/00—Properties characterising the ingredient of the composition
  • C08L2207/06—Properties of polyethylene
  • C08L2207/062—HDPE

Definitions

• the present invention relates to the production of artificial paper of improved physical characteristics yet [52] U.S. Cl. 264/22; 260/4243; 260/4246; which retains the advantageous properties of cellulose 260/4256; 260/889; 260/897 A; 260/897 B; paper. 260/897 C; 264/80; 264/83; 264/234; 264/284
• This novel artificial paper is comprised of (a) at least [Sl] ll'lt.
• the present invention relates to a film resembling paper and to processes for'the manufacture thereof.
• cellulose paper is characterized by lower specific strengths and elongations at break and .by greater rigidity. Moreover. the resistance to tearing of cellulose paper is relatively poor and practically equal in both directions of the plane of the paper. Apart from these measurable properties. cellulose paper is characterized by some specific properties, namely:
• the synthetic materials may provide additional properties not possessed by cellulose paper. such as impermeability to water vapor and gases. resistance to greases. dimensional stability under various atmospheric conditions. and scalability.
• a synthetic film may for example be treated by one of the following processes:
• the base polymer in the film provides the mechanical properties. This film may or may not be oriented.
• paper-like films which are simple films the paper-like feel of which is obtained by a controlled melt fracture phenomenon during extrusion. These films are normally manufactured to form a film imitating tissuepaper.
• spun-bonded artificial papers also exist, which are papers manufactured with synthetic fibres instead of cellulose fibres. These papers may also be subsequently coated.
• Another type of artificial paper is obtained from a composition containing at least one high density polyethylene, a copolymer of ethylene and a vinyl compound (for example vinyl acetate. acrylic ester. etc.). mineral fillers, and unmodified polystyrene. This mixture must first be calendered before its extrusion.
• an artificial paper composed of (a) olefinic resins. (b) resins of the group comprising styrene resins, acrylic resins, acetal resins. phenol resins. (c) fillers and (d) optionally a synthetic elastomer. this mixture likewise being calendered. extruded, and then additionally subjected to biorientation.
• the process according to the invention for the manufacture of an artificial paper requiring neither calendering nor biorientation comprises homogenizing in a conventional rotary mixer a composition containing the following:
• At least one rigid polyolefin (A) selected from the group consisting of homopolymers and copolymers of ethylene. propylene, and butylene. and also mixtures thereof, having a melt index of at most 1 decigramme per minute:
• adjuvants (E) selected from the group consisting of antioxidizing agents. heat stabilizers. optical bleaching agents. pigments, coloring agents, antistatic agents and lubricants, in that the mixture thus homogenized is subjected to extrusion in order to obtain an artificial paper. and that the artificial paper thus obtained. if desired. is subjected to surface treatment.
• adjuvants (E) selected from the group consisting of antioxidizing agents. heat stabilizers. optical bleaching agents. pigments, coloring agents, antistatic agents and lubricants, in that the mixture thus homogenized is subjected to extrusion in order to obtain an artificial paper. and that the artificial paper thus obtained. if desired. is subjected to surface treatment.
• rigid polyolefin (A) is understood a high density polyethylene. an isotactic polypropylene. or an isotactic polybutene which has a melt index (M.l.) of at most I decigramme/minute. preferably lower than 0.2 decigramme per minute. measured according to the standard ASTM D l238/57T. Nevertheless. the rigid polyolefin (A) may also consist of a physical mixture of these homopolymers with one another. or of copolymers obtained from ethylene. propylene. and/or butene.
• the polyolefin (A) has a modulus of elasticity higher than 2000 kg per cm measured according to the standard ASTM D 882/6lT.
• the polyolefin (A) is used in the composition according to the invention at the rate of 94.8 percent by weight. preferably from 40 to 80 percent by weight; it provides the artificial paper of the invention with rigidity and constitutes its framework.
• the polymer (B) which is incompatible with the rigid polyolefin (A) and which when extruded by itself supplies a brittle. hard. fragile film. is obtained by polymerization of a preponderant quantity of a polymerizable.
• ethylene-unsaturated monomer having the end group CH- C selected particularly from the group consisting of styrene. styrene haloand alkylsubstituted on the side chain or on the nucleus.
• the polymer (B) imparts hardness and tearability to the artificial paper manufactured from this composition.
• the properties of the polymer (B) may be modified by the conjoint utilisation of minor amounts of olefinic or diolefinic elastomers. derived for example from isobutylene. butadiene. isoprene. etc.. in a proportion representing at most 49 percent by weight of the polymer (B). It is also possible to modify the polymer (B) by external plastification with conventional plasticizers for vinyl resins. such as for example dioctyl phthalate. tricresyl phosphate. in an amount from 0.1 to 30 percent by weight of the polymer (B).
• the M.l. of the polymer (B) must be lower than l0 decigrammes per minute. preferably lower than 5.
• the polymer (B) is used in an amount from 0.l to percent by weight. preferably from 5 to 30 percent by weight. of the total composition of the invention.
• the macromolecular material (C) provides compatibility in the molten state between the polyolefin (A) and the polymer (B). It is obtained in two ways: l by copolymerisation of two monomers, one of which is compatible with the polyolefin (A). for example ethylene. propylene. or butylene. and the other is compatible with the polymer (B). for example isobutylene. bu-
• macromolecular materials (C) mention'will be made of a 50/50 ethylene/isobutylene copolymer.
• the macromolecular material (C) must be of at most 2 decigrammes per minute. preferably lower than 1 decigramme per minute. It is used in the composition of the invention at the rate of 0.1 to 35 percent by weight of the total mixture. preferably at the rate of 0.l to 25 percent by weight.
• the inorganic filler (D) is selected from inorganic substances which impart opaqueness and a suitable surface structure to the artificial paper of the invention. It may consist of talc. titanium dioxide. kaolin. zeolites. silica. zinc oxide. natural or precipitated calcium carbonate. magnesium carbonate. barytine. etc.
• the granulometry of the inorganic filler will as a maximum amount to 50 microns. Granulometry higher than this limit is disadvantageous because of the formation of grains which are detrimental to the uniformity of the artificial paper.
• the amount of inorganic filler added represents from 5 to 45 percent by weight of the total composition of the artificial paper of the invention. preferably from 5 to 25 percent by weight.
• the adjuvants (E) are constituted by:
• thermal stabilizers such as diphenylthiourea. alphaphenyl-indol. barium. cadmium. or zinc palmitate or stearate. tris-nonlyphenyl phosphite. etc.
• antioxidizing agents such as 4.4'-thio-bis(6-t-butylmetacresol 4.4-methylene-bis( 2.6-di-tbutylphenol). butylated hydroxytoluenes. etc.
• optical bleaching agents such as sulfonated derivatives of stilbene.
• organic coloring agents such as the phthalocyanines. disazoic coloring agents. chlorinated indanthrenes. etc.
• inorganic pigments such as zinc chromate. cadmium sulfide. iron oxide. etc.
• lubricants such as magnesium and calcium stearate.
• adjuvants (E) are added to the composition of the artificial paper according to the invention in an amount ranging from 0 to 10 percent by weight.
• the components (A). (B). (C). (D), and (E) are mixed together in a mixer of conventional construction. preferably in an ordinary rotary mixer.
• the composition of the invention therefore makes it possible to eliminate calendering and subsequent granulation before extrusion. which constitutes a considerable saving in manufacturing costs.
• a suitable way of preparing this mixture consists in adding components (A). (B). and (C) with a lubricant to the rotary mixer. then adding to the resulting mixture the components (D) and (E), which are in the form of a powder. This technique is not necessary if the components (D) and (E) are added in the form of a master batch.
• the length of the operation of mixing in the rotary mixer amounts at most to 60 minutes and is preferably from to 45 minutes. at ambient temperature.
• the homogeneous mixture thus obtained is subjected to extrusion in an apparatus of conventional design. in which the mixture is brought to a temperature achieving at most 290C.
• the extrusion temperature may vary between 100 and 290C in dependence on the composition of the mixture. Moreover. while remaining within the temperature limits specified above. temperature EXAMPLE I.
• a high density polyethylene having a melt index of l dg/min (component A) percent by weight of a mixture of the impact polystyrene type containing 90 percent polystyrene and 10 percent polybutadiene. with a melt index of 3 dg/min under a pressure of 100 psi (7 kg/cm") (comgradients may exist from the supply zone of the ex- 15 ponen't B) truder to the end zone of the extrusion die. percent by weight of a 50/50 mixture of polyethyl-
• the extruder may contain one or more extrusion ene and polyisobutylene with a melt index of 0.2
• the g/min (component C) composition obtained should be perfectly homogene- 10 percent by weight of titanium dioxide passing ous at the outlet of the die. through a 50 micron screen (component D)
• the die should in turn be constructed so that the ex- 4 percent by weight of precipitated calcium carbonate truded film has a regular final calibre. passing through a 50 micron screen (component D)
• the properties of the artificial paper ob- 1 percent by weight of paraffin oil (component E). tained at the outlet of the die are such that subsequent The components (A). (B), and (C) are wetted with biorientation is unnecessary, which provides a second 25 the compound (E) before incorporating the fillers (D).
• the artificial paper according to the invention may is then passed into a laboratory extruder of the type L then undergo surface treatment to improve subsequent 20 D, with a round die, at a temperature of 235C;
• Softening temperature Start C 121 Total 133 Dimensional variations in SM nil in 24h in water at 20C ST nil SM machine direction S'l transversal direction number of ml of air passing through a l m film. with a pressure difference of 1 atmosphere between the faces of the film. in 24 hours.
• This treatment which is well knownin the field of plastics. may consist in subjecting the paper to the action of a flame. corona effect. oxidizing chemical agents. etc.
• the surface treatment of the paper as described above may bepreceded by an operation of em-
• the properties of tearability, impact resistance, rigidity, and permeabilities are properties which depend on the thickness of the paper, while the breaking load, elongation at break, and modulus of elasticity are properties independent of the thickness of the paper.
• EXAMPLE 2 The following are mixed in an ordinary rotary mixer: 35 percent by weight of a high density polyethylene having a melt index of 0.4 dg/min (component A) l4 percent by weight of a styrene-butadiene (90/10) copolymer having a melt index of 3.5 dg/min under a pressure of 100 psi (7 kg/cm (component B) percent by weight of an ethylene-isobutylene (50/50) copolymer having a melt index of 0.2 dg/min (component C) 20 percent by weight of a master batch of titanium dioxide and of high density polyethylene (60/40) having a melt index of 8 dg/min (components A and D) [0 percent by weight of a master batch of calcium carbonate and of high density polyethylene (50/50) having a melt index of4 dg/min (components A and D) percent by weight of antistatic agent (component E) consisting ofa mixture ofC C
• the artificial paper obtained in this manner possesses characteristics similar to those of the paper prepared in Example 1.
• a master batch consisting of a 50/50 mixture of titanium dioxide and high density polyethylene with a melt index equal to 5 dg/min (component A D).
• optical bleaching agent component E
• the properties of the artificial paper obtained are similar to those of the paper prepared in Example I.
• the artificial paper of the invention can be printed in particular by the following processes: offset, li-tho, letterpress, gravure, flexography, silk screen, it can be impulse or heat sealed, it can be stuck on ordinary paper with glues normally suitable for polyethylene, it can be laminated on different types of film, on cellophane, etc., with the aid of standard glues, it is thermoformable, so that embossing can be carried out and any desired surface structures obtained by simply passing over heated rollers.
• the artificial paper manufactured according to the present invention can be used for making maps of any kind: tourist maps, topographical maps. road maps, etc., for printing instructions on official documents (driving licenses, hunting permits, fishing permits), for forms, catalogues. etc.
• the synthetic paper according to the invention can also be used for any artistic printing application and for posters displayed outdoors.
• [t can also be used for printing childrens' books because the pages are washable with water.
• the synthetic paper of the invention does not form dust, it is recommended for special applications in certain industries (for example the manufacture of transistors) where the presence of dust is not allowable.
• the artificial paper of the invention is very particularly recommended for use in places where oil or grease is found, for example as manuals for the greasing of cars. machines, etc.. as self-adhesive labels resisting oils and greases. etc.
• a process for the manufacture of artificial paper requiring neither calendering nor biorientation which comprises homogenizing in a conventional rotary mixer a composition containing:
• At least one rigid polyolefin (A) selected from the group consisting of homopolymers and copolymers of ethylene, propylene, and butylene, and also mixtures thereof, and
• melt index of at most 1 dg./min.
• polymer (B) which is incompatible with the rigid polyolefin (A) and which when extruded by itself produces a brittle film which has a melt index lower than l0 dg./min..
• the polymer (B) being selected from the group consisting of homopolymers and copolymers containing a preponderant amount of styrene an amount within the range of 20 to 25 percent by weight of a macromolecular material (C), said amount being sufficient to produce compatibility between (A) and (B), selected from the group consisting of:
• said macromolecular material having a melt index of at most 2 dg/min.:
• adjuvants (E) selected from the group consisting of antioxidizing agents. thermal stabilizers. optical bleaching agents. pigments. coloring materials, antistatic agents. and lubricants.
• the mixture thus homogenized being subjected to extrusion to obtain an artificial paper and the artificial paper thus obtained. if desired, being subjected to surface treatment.
• polyolefin (A) is selected from the group consisting of high density polyethylene. isotactic polypropylene. and isotactic polybutene.
• polyolefin (A) is a physical mixture of at least two polyolefins selected from the group consisting of high density polyethylene. isotactic polypropylene. and isotactic polybutene.
• polyolefin (A) is a copolymer obtained from at least two olefins selected from the group consisting of ethylene. propylene and butylene.
• polymer (B) is constituted by a mixture containing a major amount of a homopolymer of styrene and a minor amount of a homopolymer obtained by polymerization of an olefinic compound selected from the group consisting of isobutylene. butadiene. and isoprene.
• polymer (B) is a copolymer obtained by copolymerization of a major amount of styrene and a minor amount of a polymerizable olefinic monomer selected from the group consisting of isobutylene. butadiene. and isoprene.
• the macromolecular material (C) is selected from the group consisting of a 50/50 ethylene-isobutylene copolymer and a 75/25 ethylene-butadiene copolymer.
• the inorganic filler (D) is selected from the group consisting of talc. titanium dioxide. kaolin. zeolites. silica. zinc oxide. natural or precipitated calcium carbonate. magnesium carbonate. and barytine.
• thermal stabilizer used as adjuvant (E) is selected from the group consisting of diphenylthiourea. alpha-phenylindol. barium palmitate. cadmium palmitate, zinc palmitate, barium stearate, cadmium stearate. zinc stearate. and tris-nonylphenyl phosphite.
• antioxidizing agent used as adjuvant (E) is selected from the group consisting of 4,4'-thio-bis(6-t-butyl-metacresol). 4.4'-methylene-bis(2,6-di-t-butylphenol), and butylated hydroxytoluenes.
• optical bleaching agent used as adjuvant (E) is selected from the class of sulfonated derivatives of stilbene.
• organic coloring agent used as adjuvant (E) is selected from the group consisting of phthalocyanines. disazoic coloring agents. and chlorinated indanthrenes.
• pigment used as adjuvant (E) is selected from the group consisting of zinc chromate. cadmium sulfide. and iron oxide.
• lubricant used as adjuvant (E) is selected from the group consisting of magnesium stearate. calcium stearate. and paraffin oil.

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• Chemical Kinetics & Catalysis (AREA)
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• Organic Chemistry (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Compositions Of Macromolecular Compounds (AREA)

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• 1970
  • 1970-07-03 BE BE752917D patent/BE752917A/xx unknown
• 1971
  • 1971-06-28 NL NL7108905A patent/NL7108905A/xx unknown
  • 1971-06-29 DK DK319571A patent/DK132090C/da active
  • 1971-06-29 FR FR7124041A patent/FR2097165B1/fr not_active Expired
  • 1971-06-29 PL PL1971149111A patent/PL81823B1/pl unknown
  • 1971-06-29 US US158060A patent/US3876735A/en not_active Expired - Lifetime
  • 1971-06-29 RO RO7100067495A patent/RO63330A/ro unknown
  • 1971-06-29 CA CA117,036A patent/CA978685A/en not_active Expired
  • 1971-06-30 GB GB3064871A patent/GB1336492A/en not_active Expired
  • 1971-06-30 DE DE19712132510 patent/DE2132510A1/de active Pending
  • 1971-06-30 ZA ZA714301A patent/ZA714301B/xx unknown
  • 1971-06-30 LU LU63443D patent/LU63443A1/xx unknown
  • 1971-07-01 CH CH972971A patent/CH544185A/fr not_active IP Right Cessation
  • 1971-07-02 HU HUUI176A patent/HU166037B/hu unknown
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