US5364585A — Injection orientation blow molding method

Claim 1

Independent Claim 171 words

An injection orientation blow molding method comprising the steps of: injecting and filling molten resin into an injection mold to form a preform; holding a mouth portion of said preform by a lip mold cooperating with said injection mold for forming said mouth portion; transferring a preform by said lip mold from the injection mold to a blow mold; and orientation blow molding the preform into a thin-wall hollow molded article, the method being characterized by further comprising: quick cooling the preform in said injection mold by an amount sufficient to form a skin layer on a surface of the preform which enables the preform to maintain its shape; removing the preform from the injection mold when an internal portion of the preform lying inward from the skin layer is at a higher temperature than the skin layer; and orientation blow molding the preform within a given time interval which terminates before a surface temperature of the preform, which rises due to the elevated internal temperature, reaches a predetermined peak temperature.

Claim 2

Dependent Claim 171 words

An injection orientation blow molding method comprising the steps of: injecting and filling molten resin into an injection mold to form a preform; holding a mouth portion of said preform by a lip mold cooperating with said injection mold for forming said mouth portion; transferring a preform by said lip mold from the injection mold to a blow mold; and orientation blow molding the preform into a thin-wall hollow molded article, the method being characterized by further comprising: quick cooling the preform in said injection mold by an amount sufficient to form a skin layer on a surface of the preform which enables the preform to maintain its shape; removing the preform from the injection mold when an internal portion of the preform lying inward from the skin layer is at a higher temperature than the skin layer; and orientation blow molding the preform within a given time interval which terminates before a surface temperature of the preform, which rises due to the elevated internal temperature, reaches a predetermined peak temperature.

Claim 3

Dependent Claim 63 words

An injection orientation blow molding method according to claim 1 further comprising the step of controlling the internal heat of various portions of the preform by providing said injection mold with a cavity for receiving the molten resin having a varying wall thickness to control the thickness of the preform to obtain a desired heat quantity, which heat quantity differs with wall thickness.

Claim 4

Dependent Claim 72 words

An injection orientation blow molding method according to claim 1 further comprising the step of cooling the preform by removing the preform from the injection mold and maintaining the preform in the released condition for a predetermined time interval prior to initiation of the orientation blow molding step wherein the time interval in which the preform is so maintained to make orientation blow molding possible at any wall thickness of the preform.

Claim 5

Dependent Claim 67 words

An injection orientation blow molding method according to claim 1 wherein the step of injecting and filling to form a preform further comprises the step of providing the injection mold with a cavity which controls the wall thickness of the preform wherein the thickness of the preform is selected according to the degree of orientation various portions of the preform are to undergo during orientation blow molding.

Claim 6

Dependent Claim 46 words

The method of claim 1 wherein the preform is formed from polyethylene terephthalate and the step of removing the preform further includes removing the preform from the injection mold when the surface temperature of the preform is in the range of 60° C. to 70° C.

Claim 7

Dependent Claim 163 words

An injection orientation blow molding method comprising the steps of: quick cooling a preform made of a polyethylene terephthalate in an injection mold by an amount sufficient to form a skin layer on the surface of the preform engaging the injection mold, said skin layer enabling the preform to maintain its shape upon release of the preform from the mold; releasing the preform from the injection mold at a time such that, immediately after release from the injection mold, the temperature of the skin layer is above 60° C. and below 70° C. and an internal portion of the preform lying inward from the skin layer is at a higher temperature than the skin layer; and orientation blow molding the preform during a given time interval which terminates before the surface temperature of the preform reaches a peak temperature, and wherein said time interval starts when the surface temperature is above 80° C. and terminates when the surface temperature is below 95° C.

Claim 8

Dependent Claim 163 words

An injection orientation blow molding method comprising the steps of: quick cooling a preform made of a polyethylene terephthalate in an injection mold by an amount sufficient to form a skin layer on the surface of the preform engaging the injection mold, said skin layer enabling the preform to maintain its shape upon release of the preform from the mold; releasing the preform from the injection mold at a time such that, immediately after release from the injection mold, the temperature of the skin layer is above 60° C. and below 70° C. and an internal portion of the preform lying inward from the skin layer is at a higher temperature than the skin layer; and orientation blow molding the preform during a given time interval which terminates before the surface temperature of the preform reaches a peak temperature, and wherein said time interval starts when the surface temperature is above 80° C. and terminates when the surface temperature is below 95° C.

Claim 9

Dependent Claim 51 words

An injection orientation blow molding method according to claim 6 wherein the step of quick cooling the preform further comprises controlling the time when the preform is cooled to occur within a specific time interval to render orientation blow molding after release possible regardless of the wall thickness of the preform.

Claim 10

Dependent Claim 96 words

An injection orientation blow molding method according to claim 6 wherein the heat of the internal portion of the preform is controlled by maintaining the injection mold at a predetermined cooling temperature and by providing the mold with a cavity receiving molten resin having a varying wall thickness to control the wall thickness of the preform such that the degree of orientation of the preform during orientation blow molding is controlled by a temperature different at the desired portions of the preform, the temperature at each portion of the preform being a function of wall thickness.

Claim 11

Dependent Claim 82 words

An injection orientation blow molding method according to claim 6 further comprising a step of injection molding the preform in said injection mold wherein the injection mold has a cavity for receiving the molten resins, said molten resin being injection molded in the cavity and wherein the dimensions of the cavity control the thickness of the injection molded preform and wherein the thickness is controlled according to the desired degree of orientation various portions of the preform undergo during orientation blow molding.

Claim 12

Dependent Claim 154 words

An injection orientation blow molding method comprising the steps of: making a preform of polypropylene in an injection mold; quick cooling the preform by an amount sufficient to form a skin layer on the surface of the preform engaging the injection mold, said skin layer enabling the preform to maintain its shape upon release of the preform from the mold; releasing the preform from said injection mold such that, immediately after release from the mold, the temperature of the skin layer is above 90° C. and below 100° C. and an internal portion of the preform lying inward from the skin layer is at a higher temperature than the skin layer; and orientation blow molding the preform during a time interval which begins when the surface temperature of the preform is above 100° C. and which terminates when the surface temperature of the preform is below a peak temperature and is below 122° C.

Claim 13

Dependent Claim 154 words

An injection orientation blow molding method comprising the steps of: making a preform of polypropylene in an injection mold; quick cooling the preform by an amount sufficient to form a skin layer on the surface of the preform engaging the injection mold, said skin layer enabling the preform to maintain its shape upon release of the preform from the mold; releasing the preform from said injection mold such that, immediately after release from the mold, the temperature of the skin layer is above 90° C. and below 100° C. and an internal portion of the preform lying inward from the skin layer is at a higher temperature than the skin layer; and orientation blow molding the preform during a time interval which begins when the surface temperature of the preform is above 100° C. and which terminates when the surface temperature of the preform is below a peak temperature and is below 122° C.

Claim 14

Dependent Claim 51 words

An injection orientation blow molding method according to claim 10 wherein the step of quick cooling the preform further comprises controlling the time when the preform is cooled to occur within a specific time interval to render orientation blow molding after release possible regardless of the wall thickness of the preform.

Claim 15

Dependent Claim 88 words

An injection orientation blow molding method according to claim 10 wherein the temperature of the internal portion of the preform is controlled by maintaining the injection mold at a predetermined cooling temperature and by providing the injection mold with a cavity receiving molten resin having a varying wall thickness to control the wall thickness of the preform such that the degree of orientation of the preform during orientation blow molding is controlled by temperature at each portion of the preform, the temperature being a function of wall thickness.

Claim 16

Dependent Claim 82 words

An injection orientation blow molding method according to claim 10 further comprising a step of injection molding the preform in said injection mold wherein the injection mold has a cavity for receiving the molten resin, said molten resin being injection molded in the cavity and wherein the dimensions of the cavity control the thickness of the injection molded preform and wherein the thickness is controlled according to the desired degree of orientation various portions of the preform undergo during orientation blow molding.

Claim 17

Independent Claim 248 words

A method for injection orientation blow molding a thin walled hollow molded article comprising the steps of: (a) providing an injection mold for molding a preform and including a lip mold for forming a mouth portion and a body mold for forming the main body portion, said injection mold having cavity means designed to provide a preform of a predetermined configuration; (b) injecting molten resin into the injection mold cavity means; (c) holding the mouth portion of said preform by said lip mold which cooperates with the body mold to initially form the preform; (d) releasing the preform from the body mold; (e) transferring the preform from the injection mold towards a blow mold by means of said lip mold; (f) orientation blow molding the preform into a thin wall hollow molded article in said blow mold; said method being characterized by the step of quick cooling the preform after completing step (c) and before performing step (d) to control the temperature of said injection mold to form a skin layer to maintain the shape of the preform engaging said injection mold; step (d) further comprising releasing the preform therefrom during an interval which begins when an internal temperature of the preform is higher than the temperature of the skin layer and which ends before the temperature of the preform skin layer has reached a peak value; and blow molding the preform prior to the time that the temperature of the skin layer reaches said predetermined peak value.

Claim 18

Independent Claim 248 words

A method for injection orientation blow molding a thin walled hollow molded article comprising the steps of: (a) providing an injection mold for molding a preform and including a lip mold for forming a mouth portion and a body mold for forming the main body portion, said injection mold having cavity means designed to provide a preform of a predetermined configuration; (b) injecting molten resin into the injection mold cavity means; (c) holding the mouth portion of said preform by said lip mold which cooperates with the body mold to initially form the preform; (d) releasing the preform from the body mold; (e) transferring the preform from the injection mold towards a blow mold by means of said lip mold; (f) orientation blow molding the preform into a thin wall hollow molded article in said blow mold; said method being characterized by the step of quick cooling the preform after completing step (c) and before performing step (d) to control the temperature of said injection mold to form a skin layer to maintain the shape of the preform engaging said injection mold; step (d) further comprising releasing the preform therefrom during an interval which begins when an internal temperature of the preform is higher than the temperature of the skin layer and which ends before the temperature of the preform skin layer has reached a peak value; and blow molding the preform prior to the time that the temperature of the skin layer reaches said predetermined peak value.

Claim 19

Dependent Claim 45 words

The method of claim 14 wherein the step of quick cooling the preform further includes the step of lowering the temperature of the skin layer of the preform to a value which is less than a temperature value which is acceptable for orientation blow molding.

Claim 20

Dependent Claim 53 words

The method of claim 14 wherein the step of orientation blow molding the preform prior to the time that the temperature of the skin layer reaches said predetermined peak value further comprises initiating the orientation blow molding at least one-half second before the skin layer of the preform reaches said predetermined peak value.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1997-11-14	1998-05-16	1998-11-15	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	2001-11-14	2002-05-16	2002-11-15	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2005-11-14	2006-05-16	2006-11-15	$7700.00	Window Closed / Lapsed

Injection orientation blow molding method

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