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US3980611A Expired / Lapsed US ⏱️ 0.0 years remaining

Filled thermoplastic films

Assignee: EIDP Inc
•
Filing: 1973-01-18
•
Granted: 1976-09-14
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Expires: 1993-01-18
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Abstract

Abstract A thermoplastic film having dispersed therein an inert material consisting essentially of: 1. coarse particles having a size greater than 2.5 microns in a concentration determined by the formula C.sub.1 = K.sub.coarse/T 0.6 where C 1 is the concentration of coarse particles in parts per million, K coarse is at least equal to an emperically determined value of K coarse at the minimum concentration of coarse particles which permits escape of air during film wind-up, and T is film thickness in mils, 2. medium particles having a size of 1 to 2.5 microns in a concentration determined by the formula C.sub.2 = K.sub.medium/T 0.6 where C 2 is the concentration of medium particles in parts per million, K medium is no greater than an emperically determined value of K medium at the concentration of medium particles in a film having a clarity of 50%, and T is film thickness in mils, and 3. fine particles having a size less than 1 micron in a concentration determined by the formula: C.sub.3 = K.sub.fine/T 0.6 where C 3 is the concentration of fine particles in parts per million, K fine is at least equal to an emperically determined value of K fine at an effective concentration of fine particles to give a film static coefficient of friction less than about 1, and T is film thickness in mils, with the provisos that: A. the total K total = K coarse + K medium + K fine is equal to or less than about 2,510, and B. the ratio of K medium /K total is equal to or less than about 0.3 Also a process for preparing the film. The filler material provides excellent winding characteristics while maintaining commercially acceptable clear films.

Inventors

  • 👤 Jerrel Charles Anderson
  • 👤 Richard Jay England
  • 👤 Gunter Friedrich Meier

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 05:14
CPC Classifications
C; C08; C08K; C08K3/00; C08K3/32; C08K3/01; C08K3/013; G; G11; G11B; G11B5/00; G11B5/62; G11B5/73; G11B5/739; G11B5/73923; G11B5/73927

Claims Analysis

Total Claims: 19
Claim 1
Independent Claim 294 words
A thermoplastic film having dispersed therein an inert material selected from the group consisting of silica, kaolin, china clay, an aluminosilicate, diatomaceous earth, calcium phosphate, and mixtures thereof, the inert material consisting essentially of 1. coarse particles having a size of 2.5 to about 10 microns in a concentration determined by the formula C.sub.1 = K.sub.coarse /T.sup.0.6 where C 1 is the concentration of coarse particles in parts per million, K coarse is at least equal to an empirically determined value of K coarse at the minimum concentration of coarse particles which permits escape of air during the film windup and T is film thickness in mils, 2. medium particles having a size of 1 to 2.5 microns in a concentration determined by the formula C.sub.2 = K.sub.medium /T.sup.0.6 where C 2 is the concentration of medium particles in parts per million, K medium is no greater than an empirically determined value of K medium at the concentration of medium particles in a film having a clarity of 70%, and T is film thickness in mils, and 3. fine particles having a size less than 1 micron in a concentration determined by the formula: C.sub.3 = K.sub.fine /T.sup.0.6 where C 3 is the concentration of fine particles in parts per million, K fine is at least equal to an empirically determined value of K fine at an effective concentration of fine particles to give a film static coefficient of friction less than about 1, and T is film thickness in mils, with the provisos that: a. the total K total = K coarse + K medium + K fine is equal to or less than about 2,510, and b. the ratio of K medium /K total is equal to or less than about 0.3.
Claim 2
Dependent Claim 294 words
A thermoplastic film having dispersed therein an inert material selected from the group consisting of silica, kaolin, china clay, an aluminosilicate, diatomaceous earth, calcium phosphate, and mixtures thereof, the inert material consisting essentially of 1. coarse particles having a size of 2.5 to about 10 microns in a concentration determined by the formula C.sub.1 = K.sub.coarse /T.sup.0.6 where C 1 is the concentration of coarse particles in parts per million, K coarse is at least equal to an empirically determined value of K coarse at the minimum concentration of coarse particles which permits escape of air during the film windup and T is film thickness in mils, 2. medium particles having a size of 1 to 2.5 microns in a concentration determined by the formula C.sub.2 = K.sub.medium /T.sup.0.6 where C 2 is the concentration of medium particles in parts per million, K medium is no greater than an empirically determined value of K medium at the concentration of medium particles in a film having a clarity of 70%, and T is film thickness in mils, and 3. fine particles having a size less than 1 micron in a concentration determined by the formula: C.sub.3 = K.sub.fine /T.sup.0.6 where C 3 is the concentration of fine particles in parts per million, K fine is at least equal to an empirically determined value of K fine at an effective concentration of fine particles to give a film static coefficient of friction less than about 1, and T is film thickness in mils, with the provisos that: a. the total K total = K coarse + K medium + K fine is equal to or less than about 2,510, and b. the ratio of K medium /K total is equal to or less than about 0.3.
Claim 3
Dependent Claim 13 words
The thermoplastic film of claim 1 wherein the thermoplastic film is polyethylene terephthalate.
Claim 4
Dependent Claim 14 words
The thermoplastic film of claim 2 having a thickness of 0.1 to 3.0 mils.
Claim 5
Dependent Claim 17 words
The thermoplastic film of claim 3 having a static coefficient of friction of about 0.2 to 0.6.
Claim 6
Dependent Claim 13 words
The thermoplastic film of claim 1 wherein the inert material is calcium phosphate.
Claim 7
Dependent Claim 27 words
The thermoplastic film of claim 5 wherein the inert material is tribasic calcium phosphate of the formula 3Ca 3 (PO 4 ) 2 . Ca(OH) 2 .
Claim 8
Dependent Claim 13 words
The thermoplastic film of claim 1 wherein the thermoplastic film is a polyolefin.
Claim 9
Dependent Claim 14 words
The thermoplastic film of claim 5 wherein the inert material is calcium hydrogen phosphate.
Claim 10
Dependent Claim 13 words
The thermoplastc film of claim 5 wherein the thermoplastic material is polyethylene terephthalate.
Claim 11
Dependent Claim 54 words
In a process for preparing thermoplastic film comprising dispersing an inert material in a filmforming thermoplastic polymer and subsequently extruding the thermoplastic polymer in a molten state; the improvement wherein the inert material is at least one of silica, kaolin, china clay, an aluminosilicate, diatomaceous earth, or a calcium phosphate and consists essentially of
Claim 12
Dependent Claim 54 words
In a process for preparing thermoplastic film comprising dispersing an inert material in a filmforming thermoplastic polymer and subsequently extruding the thermoplastic polymer in a molten state; the improvement wherein the inert material is at least one of silica, kaolin, china clay, an aluminosilicate, diatomaceous earth, or a calcium phosphate and consists essentially of
Claim 13
Dependent Claim 258 words
coarse particles having a size of 2.5 to about 10 microns in a concentration determined by the formula C.sub.1 = K.sub.coarse /T.sup.0.6 wherein C 1 is the concentration of coarse particles in parts per million, K coarse is at least eqaul to an empirically determined value of K coarse at the minimum concentration of coarse particles which permits escape of air during film windup, and T is film thickness in mils, 2. medium particles having a size of 1 to 2.5 microns in a concentration determined by the formula C.sub.2 = K.sub.medium /T.sup.0.6 where C 2 is the concentration of medium particles in parts per million, K medium is no greater than an empiricaly determined value of K medium at the concentration of medium particles in a film having a clarity of 70%, and T is film thickness in mils, and 3. fine particles havng a size less than 1 micron in a concentration determined by the formula C.sub.3 = K.sub.fine /T.sup.0.6 where C 3 is the concentration of fine particles in parts per million, K fine is at least equal to an empirically determined value of K fine at an effective concentration of fine particles to give a film static coefficient of friction less than about 1, and T is film thickness in mils, with the provisos that: a. the total K total = K coarse + K medium + K fine is equal to or less than about 2,510, and b. the ratio of K medium /K total is equal to or less than about 0.3.
Claim 14
Dependent Claim 258 words
coarse particles having a size of 2.5 to about 10 microns in a concentration determined by the formula C.sub.1 = K.sub.coarse /T.sup.0.6 wherein C 1 is the concentration of coarse particles in parts per million, K coarse is at least eqaul to an empirically determined value of K coarse at the minimum concentration of coarse particles which permits escape of air during film windup, and T is film thickness in mils, 2. medium particles having a size of 1 to 2.5 microns in a concentration determined by the formula C.sub.2 = K.sub.medium /T.sup.0.6 where C 2 is the concentration of medium particles in parts per million, K medium is no greater than an empiricaly determined value of K medium at the concentration of medium particles in a film having a clarity of 70%, and T is film thickness in mils, and 3. fine particles havng a size less than 1 micron in a concentration determined by the formula C.sub.3 = K.sub.fine /T.sup.0.6 where C 3 is the concentration of fine particles in parts per million, K fine is at least equal to an empirically determined value of K fine at an effective concentration of fine particles to give a film static coefficient of friction less than about 1, and T is film thickness in mils, with the provisos that: a. the total K total = K coarse + K medium + K fine is equal to or less than about 2,510, and b. the ratio of K medium /K total is equal to or less than about 0.3.
Claim 15
Dependent Claim 12 words
The process of claim 10 wherein the thermoplastic polymer is polyethylene terephthalate.
Claim 16
Dependent Claim 16 words
The process of claim 11 wherein the film has a thickness of 0.1 to 3.0 mils.
Claim 17
Dependent Claim 12 words
The process of claim 11 wherein the inert material is calcium phosphate.
Claim 18
Dependent Claim 26 words
The process of claim 13 wherein the inert material is tribasic calcium phosphate of the formula 3Ca 3 (PO 4 ) 2 . Ca(OH) 2 .
Claim 19
Dependent Claim 11 words
The process of claim 10 wheren the thermoplastic polymer is polyolefin.

References Cited (Backward Citations)

US3271343A Cited
US3419460A Cited
US3382206A Cited
US3374199A Cited
US3520846A Cited
US3445259A Cited
US3607818A Cited
US3590528A Cited
US3821156A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-09-14 1980-03-15 1980-09-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-09-14 1984-03-15 1984-09-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-09-14 1988-03-15 1988-09-14 $7700.00 Window Closed / Lapsed

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