Containers with improved crease-crack resistance

A substantially form retaining container for a fluid having a wall defining an interior and an exterior, at least a part of said wall comprising a plurality of layers including:

• (A) a first relatively stiff layer in close proximity to said interior of said container and formed from a polymer;
• said polymer, when in close proximity to said fluid, displaying less susceptibility to crease cracking than when out of close proximity to said fluid, said first layer being sufficiently thick so that the part of said first layer located layer away from said interior of said container has greater stiffness than said interior surface of said first layer when said first layer is in close proximity to said fluid;
• and
• (B) a second substantially continuous layer occurring at the portion of said part of said wall wherever said first layer occurs and being located, at said portion, toward the exterior of said container from said first layer, said second layer having less susceptibility to crease cracking than said part of said first layer located away from said interior of said container.

A substantially form retaining container having a wall defining an interior and an exterior, at least a part of said wall comprising a plurality of layers including:

• (A) a relatively stiff first layer;
• (B) a second substantially continuous layer occurring at the portion of said part of said wall wherever said first layer occurs and being located, at said portion, toward the exterior of said container from said first layer, said second layer having less stiffness than said first layer;
• and
• (C) a third substantially continuous layer occurring at the portion of said part of said wall wherever said first layer occurs and being located, at said portion, toward the interior of said container from said first layer, said third layer having less stiffness than said first layer.

A substantially form retaining container having a wall defining an interior and an exterior, at least a part of said wall comprising a plurality of layers including:

• (A) a first relatively stiff first layer;
• (B) a second substantially continuous layer occurring at the portion of said part of said wall wherever said first layer occurs and being located, at said portion, toward the exterior of said container from said first layer, said second layer having less susceptibility to crease cracking than said first layer;
• and
• (C) a third substantially continuous layer occurring at the portion of said part of said wall wherever said first layer occurs and being located, at said portion, toward the interior of said container from said first layer, said third layer having less susceptibility to crease cracking than said first layer.

A method for molding a substantially form retaining container for oil having a wall defining an interior and an exterior comprising:

• (A) forming a first relatively stiff layer in close proximity to said interior of said container from a polymer;
• said polymer, when on the interior surface of said layer and in close proximity to said oil, absorbing said oil, and after absorbing said oil, displaying less stiffness than when out of close proximity to said oil, said first layer being formed sufficiently thick so that the part of said first layer located layer away from said interior of said container has greater stiffness than said interior surface of said first layer when said first layer is in close proximity to said oil;
• and
• (B) forming a second substantially continuous layer at the portion of said wall wherever said first layer occurs, and at said portion, toward the exterior of said container from said first layer, said second layer having less stiffness than said part of said first layer located away from said interior of said container.

A method for molding a substantially form retaining container for fluid having a wall defining an interior and an exterior comprising:

• (A) forming a first relatively stiff layer in close proximity to said interior of said container from a polymer;
• said polymer, when in close proximity to said fluid, displaying less susceptibility to crease cracking than when out of close proximity to said fluid, said first layer being formed sufficiently thick so that the part of said first layer located layer away from said interior of said container has greater stiffness than said interior surface of said first layer when said first layer is in close proximity to said fluid;
• and
• (B) forming a second continuous layer at the portion of said wall wherever said first layer occurs, and at said portion, toward the exterior of said container from said first layer, said second layer having substantially less susceptibility to crease cracking than said part of said first layer located away from said interior of said container.

A method for molding a substantially form retaining having a wall defining an interior and an exterior comprising:

• (A) forming a first relatively stiff layer;
• (B) forming a second substantially continuous layer at the portion of said wall wherever said first layer occurs, and at said portion, toward the exterior of said container from said first layer, said second layer having less stiffness than said first layer;
• and
• (C) forming a third substantially continuous layer at the portion of said wall wherever said first layer occurs, and at said portion, toward the interior of said container from said first layer, said third layer having less stiffness than said first layer.

A method for molding a substantially form retaining having a wall defining an interior and an exterior comprising:

• (A) forming a first relatively stiff layer;
• (B) forming a second substantially continuous layer at the portion of said wall wherever said first layer occurs, and at said portion, toward the exterior of said container from said first layer, said second layer having less susceptibility to crease cracking than said first layer;
• and
• (C) forming a third substantially continuous layer at the portion of said wall wherever s aid first layer occurs, and at said portion, toward the interior of said container from said first layer, said third layer having less susceptibility to crease cracking than said first layer.