An apparatus (10) for converting a slit-sheet stock material (16) into an expanded dunnage product (12) includes a housing (20), a pair of rollers (22, 24) within the housing extending widthwise across a path of the sheet material, and a plurality of guide strips (90) extending from an upstream side of the pair of rollers to a downstream side of the pair of rollers at a plurality of locations spaced across the width of the path. The guide strips guide the sheet material between and around the rollers. Exemplary rollers have a plurality of grooves spaced across the width of the path, and the guide strips are received in respective grooves. The guide strips may be connected by a crossbar to form a guide member.

A dunnage conversion system (20) for expanding an unexpanded slit sheet stock material (23) to form an expanded dunnage product (26). The dunnage conversion system includes a converging chute (28) to inwardly gather laterally-extending edges of sheet stock material towards one another, causing random crumpling of the sheet stock material to form a modified ply. The conversion system also includes feed wheels (120) that advance the modified ply through the converging chute and pinch rollers (122) that cooperate with the feed wheels to expand the modified ply traveling between the feed wheels and the pinch rollers to form a dunnage product. The expanded dunnage product is expanded both in a longitudinal feed direction and in thickness as compared to the unexpanded slit sheet stock material, and thus is a three-dimensional product having increased volume and lower density per unit of length as compared to the unexpanded slit sheet stock material.

An improved expandable slit-sheet stock material is configured to aid in temporarily restricting opening of a plurality of slits of the slit-sheet stock material, such as during winding of the unexpanded stock material or during expansion of the stock material. Each slit of the plurality of slits includes one or more un-slit reinforcement portions, such as reinforcement ties, extending fully between opposite longitudinal sides of the slit, and disposed between opposed transverse endpoints of the slit. The reinforcement ties minimize or prevent tearing of the stock material during the winding or expansion. A dunnage conversion system for expanding the slit-sheet stock material includes an expander having a pair of opposed rollers. The rollers engage the stock material to effect breaking of the un-slit reinforcement portions and expansion of the slit-sheet stock material.

According to some embodiments, systems and methods for applying labeling or indicia upon expandable slit sheet cushioning material is provided, including, in some examples, a) providing one or more unslit region within the expandable slit sheet material, b) providing one or more label or the like that is adhered or connected to a region of the expandable slit sheet material, and/or c) providing an over-layer sheet around the expandable slit sheet material.

An extensible slit sheet paper product is produced having an expandable slit pattern that forms open cells upon expansion of the paper product. The paper product is an extensible paper having an extensibility in the range from 1-9% in the machine direction and 1-5% in the cross direction. The expansion produces an array of hexagonal cells. The expanded extensible paper can be used to wrap an object for shipping by wrapping and cushioning the object in the expanded slit sheet material. The extensible, expandable slit sheet paper can be wrapped around itself to produce a void fill product.

A dunnage conversion system for expanding an unexpanded slit sheet stock material to form an expanded dunnage product. The dunnage conversion system includes a converging chute to inwardly gather laterally-extending edges of sheet stock material towards one another, causing random crumpling of the sheet stock material to form a modified ply. The conversion system also includes feed wheels that advance the modified ply through the converging chute and pinch rollers that cooperate with the feed wheels to expand the modified ply traveling between the feed wheels and the pinch rollers to form a dunnage product. The expanded dunnage product is expanded both in a longitudinal feed direction and in thickness as compared to the unexpanded slit sheet stock material, and thus is a three-dimensional product having increased volume and lower density per unit of length as compared to the unexpanded slit sheet stock material.

In the preferred embodiments, the present invention provides substantially improved slit sheet cushioning products by advantageously combining novel paper properties with novel slit patterns for improved features and characteristics. In some illustrative and non-limiting example embodiments, cushioning products of the present invention can include, e.g., a novel slit sheet material in combination with extensible paper employed as, e.g., a cushioning pad or as cushioning within an envelope product, wherein the cushioning product can be substantially more resilient, but, yet, e.g., thinner for better utilization of space.

According to some embodiments, systems and methods for applying labeling or indicia upon expandable slit sheet cushioning material is provided, including, in some examples, a) providing one or more unslit region within the expandable slit sheet material, b) providing one or more label or the like that is adhered or connected to a region of the expandable slit sheet material, and/or c) providing an over-layer sheet around the expandable slit sheet material.

In the preferred embodiments, the present invention provides substantially improved slit sheet cushioning products by advantageously combining novel paper properties with novel slit patterns for improved features and characteristics. In some illustrative and non-limiting example embodiments, cushioning products of the present invention can include, e.g., a novel slit sheet material in combination with extensible paper employed as, e.g., a cushioning pad or as cushioning within an envelope product, wherein the cushioning product can be substantially more resilient, but, yet, e.g., thinner for better utilization of space.

In accordance with a broad embodiment of the invention, a novel paper product is comprised of two or more slit sheet packing material layers, each layer having its own slit pattern design to create interlocking layers of expansion sheet packaging materials. Each layer expands to create a three dimensional open netting of cells of hexagons, and the like, and is designed to have limited nesting with its opposing layer, thereby maximizing the thickness of the combined layers as compared to nested layers. Adjacent layers have differing slit patterns and can be expanded through expander type machinery such that the expansion rates of the differing slit pattern layers can be varied to deliver the same width of exiting expanded material from each layer. Preferably the differing slit pattern produce when expanded, inclined land areas that have the same number of rows per inch, but different angles of inclination of the land areas, such that adjacent layers can interlock, that is, have a restricted amount of nesting.