US20220203188A1

US20220203188A1 - Clear lacrosse head

Info

Publication number: US20220203188A1
Application number: US17/136,165
Authority: US
Inventors: Hamilton Sean Michael Whitney; Andrew DIRKS; Keith MCKINLEY
Original assignee: East Coast Dyes Inc
Current assignee: East Coast Dyes Inc
Priority date: 2020-12-29
Filing date: 2020-12-29
Publication date: 2022-06-30

Abstract

The invention relates in general to lacrosse heads, and more particularly to preparation of a lacrosse head that is optically clear, but still maintains the desired stiffness and durability characteristics for optimal play.

Description

FIELD OF THE INVENTION

BACKGROUND OF THE INVENTION

Double-walled, synthetic lacrosse heads have revolutionized the game of lacrosse. The synthetic heads impart a lightness, maneuverability, and flexibility. These performance advantages greatly enhance players' skills and have increased the speed of the game.
In combination with qualities that enhance the skill of the game, many players desire unique esthetic characteristics, such as lacrosse heads that are optically clear, or translucent. However, obtaining such esthetic characteristics, while also maintaining the desired mechanical characteristics for optical play, has not yet been achieved.

BRIEF SUMMARY OF THE INVENTION

The present invention fulfills these needs by providing lacrosse heads that are optically clear, or translucent, but also have the desired mechanical characteristics for optical play.
Embodiments hereof are directed to a lacrosse head comprising opposing sidewalls joined at one end by a throat, the sidewalls diverging generally outwardly, and the sidewalls being connected at another end by a scoop, wherein the lacrosse head comprises a nylon polymer that exhibits greater than 60% light transmission.
In further embodiments, provided herein is a lacrosse head comprising opposing sidewalls joined at one end by a throat, the sidewalls diverging generally outwardly, and the sidewalls being connected at another end by a scoop, wherein the lacrosse head comprises a polymer that exhibits greater than 60% light transmission, and wherein the lacrosse head has a weight of about 110 g to about 150 g, a stiffness of about 20 lbf to about 35 lbf when measured at a temperature between 70° F.-75° F., and wherein the lacrosse head can withstand more than 150 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact, or wherein the lacrosse head has a weight of about 100 g to about 125 g, a stiffness of about 5 lbf to about 20 lbf when measured at a temperature between 70° F.-75°, and wherein the lacrosse head can withstand more than 20 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact.
In additional embodiments, provided herein is a lacrosse head comprising opposing sidewalls joined at one end by a throat, the sidewalls diverging generally outwardly, and the sidewalls being connected at another end by a scoop, wherein the lacrosse head comprises a nylon polymer that exhibits about 15% to about 50% light transmission, and wherein the lacrosse head has a weight of about 100 g to about 150 g, a stiffness of about 20 lbf to about 35 lbf when measured at a temperature between 70° F.-75° F., and wherein the lacrosse head can withstand more than 150 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact, or wherein the lacrosse head has a weight of about 100 g to about 125 g, a stiffness of about 5 lbf to about 20 lbf when measured at a temperature between 70° F.-75°, and wherein the lacrosse head can withstand more than 20 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact.
Also provided herein is a lacrosse head comprising opposing sidewalls joined at one end by a throat, the sidewalls diverging generally outwardly, and the sidewalls being connected at another end by a scoop, wherein the lacrosse head comprises an impact modified nylon 12 polymer that exhibits greater than 75% light transmission, and wherein the lacrosse head has a weight of less than 150 g, a stiffness of less than 30.0 lbf when measured at a temperature between 70° F.-75° F., and wherein the lacrosse head can withstand more than 250 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact.

BRIEF DESCRIPTION OF DRAWINGS

The foregoing and other features and advantages of the invention will be apparent from the following description of embodiments hereof as illustrated in the accompanying drawings. The accompanying drawings, which are incorporated herein and form a part of the specification, further serve to explain the principles of the invention and to enable a person skilled in the pertinent art to make and use the invention. The drawings are not to scale.

FIG. 1 shows an exemplary lacrosse head according to embodiments hereof.

FIG. 2 is a perspective view of a lacrosse head according to embodiments hereof.

FIG. 3A shows the experimental set-up and device used in an impact test in accordance with embodiments hereof.

FIG. 3B shows a lacrosse head following an impact test.

FIG. 4A shows the experimental set-up and device used to measure stiffness of a lacrosse head in accordance with embodiments hereof.

FIGS. 4B-4C show components used in the stiffness measurements described herein.

FIGS. 5A-5C show the results of mechanical testing of a DNA lacrosse head in accordance with embodiments hereof.

FIGS. 6A-6C show the results of mechanical testing of a Mirage 2 lacrosse head in accordance with embodiments hereof.

FIGS. 7A-7C show the results of mechanical testing of an Infinity lacrosse head in accordance with embodiments hereof.

FIG. 8 shows reference photographs of materials measured using a window tint meter.

FIGS. 9A-9C show the results of mechanical testing of a polycarbonate optically clear material in a DNA lacrosse head geometry.

FIGS. 10A-10C show the results of mechanical testing of a polycarbonate optically clear material in an infinity lacrosse head geometry.

DETAILED DESCRIPTION OF THE INVENTION

Specific embodiments of the present invention are now described with reference to the figures, wherein like reference numbers indicate identical or functionally similar elements. The following detailed description is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. Furthermore, there is no intention to be bound by any expressed or implied theory presented in the preceding technical field, background, brief summary or the following detailed description.
Embodiments hereof relate to a lacrosse head that is optically clear or translucent, providing a unique esthetic experience for the player, in comparison to traditional lacrosse heads that are prepared from plastics that do not provide any light transmission. FIG. 1 shows an exemplary lacrosse head 100 that is optically clear. As used herein, “optically clear” means that the material that is used to make the lacrosse head exhibits a light transmission of greater than 60%. The terms “optically clear,” “clear,” “optically transparent,” and “transparent” are used interchangeably herein. In other embodiments, a lacrosse head is “translucent.” As used herein, “translucent” means that the material used to make the lacrosse head exhibits a light transmission of about 10% to about 60%, and includes materials that contain a tint or coloring, but otherwise allow for the specified amount of light transmission.
FIG. 2 shows a line drawing of lacrosse head 100, showing the location of opposing sidewalls (202 and 204) joined at one end by a throat 206, the sidewalls diverging generally outwardly, and the sidewalls being connected at another end by a scoop 208. The diagram of lacrosse head 100 in FIG. 2 is not meant to be limiting, and is provided to illustrate the components of the lacrosse head, but is not meant to imply any design or specific features of the lacrosse head, other than those described herein. The materials described herein can be utilized in any design or configuration of a lacrosse head.
In embodiments, provided herein is a lacrosse head comprising opposing sidewalls (202 and 204) joined at one end by a throat (206), the sidewalls diverging generally outwardly, and the sidewalls being connected at another end by a scoop (208), wherein the lacrosse head comprises a polymer that exhibits greater than 60% light transmission.
Suitably, the polymer utilized in the lacrosse heads described herein is a nylon polymer. In exemplary embodiments, the nylon polymer is an impact modified nylon polymer, including an impact modified nylon 12 (IMPA 12). Nylon 12 has a formula [(CH₂)₁₁C(O)NH]_n, and is made from ω-aminolauric acid or laurolactam monomers that each have 12 carbons, and has the following structure:
“Impact modified” refers to the addition of one or more additional polymers or monomers, or other impact modifiers, into the nylon 12 to increase its durability and toughness.
In exemplary embodiments, the impact modified nylon 12 is GRILAMID® TR RDS 4863 from EMS-CHEMIE (Sumter, S.C.), a thermos-plastic polyamide based on aliphatic and cycloaliphatic blocks. Suitably the impact modified nylon 12 is GRILAMID® TR RDS 4863 Blue L 12309.01, having the following properties:

TABLE 1

Properties of GRILAMID ® TR RDS 4863

			Grilamid TR
Standard	Unit	State	ROS 4863

Mechanical Properties

Tensile E-Modulus

	1	mm/min	ISO 527	MPa	cond.	1400
Tensile Strength at yield	50	mm/min	ISO 527	MPa	cond.	>50
Elongation at yield	5	mm/min	ISO 527	%	cond.	7
Tensile Strength at break	50	mm/min	ISO 527	MPa	cond.	50
Elongation at break	5	mm/min	ISO 527	%	cond.	>50

Impact strength	Charpy, 23° C.	ISO 179/2-1eU	kJ/m²	cond.	no break
Srspaci strength	Charpy, −30° C.	ISO 179/2-1eU	kJ/m²	cond.	no break
Notched Impact strength	Charpy, 23° C.	ISO 179/2-1eA	kJ/m²	cond.	17
Notched Impact strength	Charpy, −30° C.	ISO 179/2-1eA	kJ/m²	cond.	*

Thermal Properties

Glass transition temperature

DSC

ISO 11357

° C.

dry

150

Heat deflection temperature HDT/A	1.80	MPa	ISO 75	° C.	dry	110
Heat deflection temperature HDT/B	0.45	MPa	ISO 75	° C.	dry	135

Maximum usage temperature	long term	ISO 257	° C.	dry	80-100
Maximum usage temperature	short term	EMS	° C.	dry	120

Electrical Properties

Dielectric strength

IEC 60243-1

KV/mm

cond.

34

Comparative tracking index

CTI

IEC 60112

—

cond.

600

Specific volume resistivity			IEC 60093	Ω · m	cond.	10¹¹
Specific surface resistivity			IEC 60093	Ω	cond.	10¹²

General Properties

Density			ISO 1183	g/cm	dry	1.00
Water absorption	23°	C./sat.	ISO 62	%	—	3.0
Moisture absorption	23°	C./50% r.h.	ISO 62	%	—	1.5
Linear mould shrinkage long	24	h/23° C.	ISO 294	%	dry	1.05
Linear mould shrinkage trans.	24	h/23° C.	ISO 294	%	dry	1.10

indicates data missing or illegible when filed

Examples of additional suitable polymeric materials that can be used or included in the lacrosse heads include polypropylene (PP), polyethylene (PE), amorphous polar plastics (e.g., polycarbonate (PC)), polymethylmethacrylate (PMMA), polystyrene (PS), high impact polystyrene (HIPS), polyphenylene oxide (PPO), glycol modified polyethylene terphthalate (PETG), acrylonitrile butadiene styrene (ABS), semicrystalline polar plastics (e.g., polyester PET and PBT), polyamide (nylon) (e.g., Nylon 6 and Nylon 6-6 (also called Nylon 6/6, Nylon 66 or Nylon 6,6), amorphous nylon, urethane, polyketone, polybutylene terephalate, acetals (e.g., DELRIN™ by DuPont), acrylic, acrylic-styrene-acrylonitrile (ASA), metallocene ethylene-propylene-diene terpolymer (EPDM) (e.g., NORDEL™ by DuPont), and composites thereof. In addition, fillers such as fiberglass, carbon fiber, mineral fill and the like can be added (for example 5-40% by weight) to create a custom polymeric composition.
As described herein, in embodiments the lacrosse head comprises a polymer, such as a nylon polymer, that exhibits greater than 50% light transmission. In further embodiments, the lacrosse head comprises a polymer, such as a nylon polymer, that exhibits greater than 60% light transmission, greater than 70% light transmission, greater than 75% light transmission, greater than 80% light transmission, greater than 85% light transmission, greater than 90% light transmission, or about 60% to about 90% light transmission, about 70% to about 90% light transmission, about 80% to about 90% light transmission, about 75% to about 85% light transmission, or about 80% to about 85% light transmission.
Light transmission can be measured by any suitable method, including for example via the use of a Window Tint Meter that measures light transmission from 0 to 100%. A Window Tint Meter is a hand held device that measures the amount of light that passes through a glass or polymeric structure. The meter can be held up to a sample of the polymers utilized to produce the lacrosse heads described herein and the percent (%) light transmission read off of the meter. The following provides an overview of the specifications of the meter used to measure light transmission:

TABLE 2

Window Tint Meter Specifications
Parameters

Display	10 mm LCD
Measurement Range	0 to 100% Light Transmission
Resolution	0.1
Accuracy	±2%
Sample Thickness	Less Than 18 mm/0.7 inch
Light Source	LED
Measuring Mode	Single/Continuous
Operating conditions	Temperature: 0~50° C. Humidity: <90%
Power Supply	4 × 1.5 V AAA Size (UM-4) Battery
Dimensions	Unit: 126 × 65 × 27 mm (5.0 × 2.6 × 1.1 inch)
	Sensor: 125 × 38 × 38 mm
Weight	100 g (Not Including Batteries)

Features:
This Window Tint Meter is a hand held device that measures the amount of light that passes through a window.
Technology is designed in accordance with GB 2410-80, ASTM D1033-61, JIS 7105-81 and other standards.
Digital display, wide measurement range, high resolution.
One key calibration, easy to use.
Solid structure, small volume, light weight, exquisite, easy to carry.
Single/Continuous measuring mode.
Use “USB data output” and “RS -232 data output” no connect with PC.
Provide “Bluetooth ™ data output” choice.
indicates data missing or illegible when filed

In embodiments, the lacrosse head has a stiffness of less than 50 lbf, when measured at a temperature of between 70° F. and 75° F.
As described herein, “stiffness” also called “compression stiffness,” refers to the force required to deflect a lacrosse head a distance of 0.25 inches, when the lacrosse head is pressed in a compressive manner when oriented vertically (compression is provided normal to scoop 208). See below and FIG. 4A regarding an exemplary stiffness measurement. The force to cause the 0.25 inch deflection varies only about over a temperature range of −15° C. to 52° C., and thus for comparison purposes, the stiffness of the lacrosse heads described herein are determined at a temperature of between about 70° F. and 75° F., suitably at about 71° F. or 72° F.
In embodiments, the stiffness of the lacrosse heads provided herein are less than about 40.0 lbf, when measured at a temperature of between 70° F. and 75° F., more suitably less than about 35.0 lbf, or less than about 33 lbf, or less than about 30 lbf, or less than about 27 lbf, or less than about 25 lbf, or less than about 23 lbf, or less than about 20 lbf, or less than about 10 lbf, or less than about 5 lbf, or the lacrosse heads have a stiffness of about 20 lbf to about 35 lbf, a stiffness of about 31 lbf to about 35 lbf, a stiffness of about 25 lbf to about 35 lbf, a stiffness of about 25 lbf to about 30 lbf; a stiffness of about 27 lbf to about 32 lbf, a stiffness of about 20 lbf to about 31 lbf, a stiffness of about 20 lbf to about 30 lbf, a stiffness of about 10 lbf to about 20 lbf, a stiffness of about 15 lbf to about 20 lbf, a stiffness of about 5 lbf to about 20 lbf, a stiffness of about 5 lbf to about 10 lbf, or a stiffness of about 15 lbf to about 25 lbf, when measured at a temperature of between 70° F. and 75° F.
In exemplary embodiments, the lacrosse head can withstand more than 150 impacts prior to failure.
As described in detail herein, an exemplary method has been developed to test the impact strength of a lacrosse head, that includes a repeated rotation of a lacrosse head impacting a spring-loaded, steel impact arm having a weight of about 2-4 lbs. Prior to each impact, the lacrosse head attains a kinetic energy of about 25-55 Joules, depending on the weight of the lacrosse head and variability in the speed of the impacts. That is, prior to each time the lacrosse head impacts the impact arm, the lacrosse head has attained a kinetic energy of about 25-55 Joules, and then impacts that impact arm, before again attaining the same kinetic energy range prior to another impact. See below and FIG. 3A regarding the exemplary testing method.
As described herein, this impact test is designed to provide a repeatable measure of the impact strength of a lacrosse head, so that different head designs and lacrosse head compositions can be compared. The number of impacts between the lacrosse head and the steel impact arm are counted. In embodiments, the lacrosse heads described herein can withstand more than 250 impacts (that is 250 contacts between the lacrosse head and the steel impact arm), prior to failure. As used herein “failure” refers to a visual crack or break 320 in the lacrosse head, rather than an elongation or plastic deformation 322 in the lacrosse head (see FIG. 3B).
A person of ordinary skill in the art will be able to calculate a kinetic energy that the lacrosse head attains prior to an impact, using standard physics principles. As described herein, the method used to determine the impact strength utilizes a rotating arm to impact the head against a steel impact arm, and thus rotational kinetic energy calculations are used to determine the kinetic energy the lacrosse head attains prior to each impact, of about 25-55 Joules.
In exemplary embodiments, the lacrosse heads described herein can withstand more than 15 impacts, more than 20 impacts, more than 25 impacts, more than 30 impacts, more than 35 impacts, more than 40 impacts, more than 50 impacts, more than 60 impacts, more than 70 impacts, more than 80 impacts, more than 90 impacts, more than 100 impacts, more than 110 impacts, more than 120 impacts, more than 130 impacts, more than 140 impacts, more than 150 impacts, more than 160 impacts, more than 170 impacts, more than 180 impacts, more than 190 impacts, more than 200 impacts, more than 210 impacts, more than 220 impacts, more than 230 impacts, more than 240 impacts, more than 250 impacts, more than 260 impacts, more than 270 impacts, more than 280 impacts, more than 290 impacts, more than 300 impacts, more than 400 impacts, more than 500 impacts, more than 600 impacts, more than 700 impacts, more than 800 impacts, more than 900 impacts, more than 1,000 impacts, more than 1,100 impacts, more than 1,200 impacts, more than 1,300 impacts, more than 1,400 impacts, or more than 1,500 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules, prior to each impact.
In embodiments of this impact test as described herein with reference to FIG. 3A, lacrosse head 100 is attached to a shaft 302, the impact arm having a length of about 25-35 inches, suitably about 30 inches (center of point of rotation to impact bar). Shaft 302 is configured to rotate in a circular path 304, suitably via a rotating motor 306, or similar device.
Lacrosse head 100 is rotated in the circular path, suitably at a rate of about 20-25 m/s (at impact), and once during each rotation, lacrosse head 100 impacts a spring-loaded, steel impact arm 308. Suitably, spring-loaded, steel impact arm has a weight of about 2-4 lbs. Prior to each impact against spring-loaded, steel impact arm 308, lacrosse head 100 attains a kinetic energy of about 25 Joules to about 55 Joules. Following the impact, spring-loaded, steel impact arm 308, deflects out of the way, allowing lacrosse head 100 to continue on its circular path and repeat the impact test. The lacrosse head attains the same range of kinetic energy (about 25 to about 55 Joules) prior to each impact.
Suitably, the impact test is repeated at cycles of 10 impacts/cycle, before the test is started again. This also allows for repeatable and simple counting of the number of impacts until the lacrosse head fails, and to inspect the lacrosse head to determine if a failure has occurred.
As described herein, suitably the lacrosse head has a weight that is less than 200 g, more suitably less than 170 g, and in embodiments, the lacrosse head has a weight that is less than 160 g, less than 150 g, less than 140 g, less than 130 g, less than 120 g, less than 110 g, or in other embodiments, the weight of the lacrosse head is between 110 g and 170 g, more suitably between 110 g and 150 g, between 110 g and 140 g, between 110 g and 140 g, between 120 g and 125 g, between 120 g and 150 g, between 130 g and 150 g, or between 140 g and 150 g.
In exemplary embodiments, the lacrosse head has a stiffness of about 20 lbf to about 31 lbf when measured at a temperature between 70° F.-75° F., a weight of about 110 g to about 130 g, and the lacrosse head can withstand more than 150 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact.
In further embodiments, the lacrosse head has a stiffness of about 5 lbf to about 20 lbf when measured at a temperature between 70° F.-75° F., a weight of about 100 g to about 125 g, and the lacrosse head can withstand more than 20 impacts prior to failure, when the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact.
In additional embodiments, provided herein is a lacrosse head comprising opposing sidewalls joined at one end by a throat, the sidewalls diverging generally outwardly, and the sidewalls being connected at another end by a scoop. Suitably, the lacrosse head comprises a polymer that exhibits greater than 60% light transmission, and the lacrosse head has a weight of about 110 g to about 150 g, a stiffness of about 20 lbf to about 35 lbf when measured at a temperature between 70° F.-75° F., and the lacrosse head can withstand more than 150 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact, or the lacrosse head has a weight of about 100 g to about 125 g, a stiffness of about 5 lbf to about 20 lbf when measured at a temperature between 70° F.-75°, and wherein the lacrosse head can withstand more than 20 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact.
In embodiments, the polymer exhibits greater than 75% light transmission. As described herein, suitably the polymer is an impact modified nylon, such as impact modified nylon 12.
In suitable embodiments, the lacrosse head can withstand more than 150 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact.
In further embodiments, the lacrosse head has a weight of about 130 g to about 150 g, a stiffness of about 25 lbf to about 30 lbf when measured at a temperature between 70° F.-75° F., and the lacrosse head can withstand more than 200 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact.
In still further embodiments, the lacrosse head has a weight of about 100 g to about 125 g, a stiffness of about 5 lbf to about 20 lbf when measured at a temperature between 70° F.-75° F., and the lacrosse head can withstand more than 30 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact.
In additional embodiments, a lacrosse head provided herein is translucent, in that it exhibits a light transmission of about 10% to about 60%, and includes materials that contain a tint or coloring, but otherwise allow for the specified amount of light transmission. For example, provided herein is a lacrosse head comprising opposing sidewalls joined at one end by a throat, the sidewalls diverging generally outwardly, and the sidewalls being connected at another end by a scoop. Suitably the lacrosse head comprises a nylon polymer that exhibits about 15% to about 50% light transmission, and

- the lacrosse head has a weight of about 100 g to about 150 g, a stiffness of about 20 lbf to about 35 lbf when measured at a temperature between 70° F.-75° F., and the lacrosse head can withstand more than 150 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact, or
- the lacrosse head has a weight of about 100 g to about 125 g, a stiffness of about 5 lbf to about 20 lbf when measured at a temperature between 70° F.-75° F., and the lacrosse head can withstand more than 20 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact.

In embodiments, the lacrosse heads described herein that are translucent comprise a nylon polymer, such as an impact modified nylon, that exhibits about 18% to about 30% light transmission, and can include a tint, such as a brown, grey, black, green, blue, red, orange, or yellow tint.
In exemplary embodiments, the lacrosse head can withstand more than 200 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact.
In further embodiments, the lacrosse head has a weight of about 130 g to about 150 g, a stiffness of about 25 lbf to about 30 lbf when measured at a temperature between 70° F.-75° F., and the lacrosse head can withstand more than 150 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact.
In further embodiments, the lacrosse head has a weight of about 120 g to about 125 g, a stiffness of about 15 lbf to about 20 lbf when measured at a temperature between 70° F.-75° F., and wherein the lacrosse head can withstand more than 30 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact.
In still further embodiments, provided herein is a lacrosse head comprising opposing sidewalls joined at one end by a throat, the sidewalls diverging generally outwardly, and the sidewalls being connected at another end by a scoop, the lacrosse head comprises an impact modified nylon 12 polymer that exhibits greater than 75% light transmission, and the lacrosse head has a weight of less than 150 g, a stiffness of less than 30.0 lbf when measured at a temperature between 70° F.-75° F., and wherein the lacrosse head can withstand more than 250 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact.

EXAMPLES

Example 1: Compression Stiffness

The following example describes the methods used to measure the compression stiffness (stiffness) of a lacrosse head.
Compression stiffness determinations are used in order to understand how flexible a lacrosse head is at a variety of temperatures. The stiffness of a lacrosse head is one of the first things lacrosse players check. Many players want a stiff head while others prefer a more flexible head.

Equipment

MTS Exceed Model E43 (see FIG. 4A)
Custom 3D Printed Attachments

- Lacrosse Head Coupling (402) (see FIG. 4B)
- Grooved Pressure Plate Attachment (404) (see FIG. 4C)

Infrared Laser Thermometer

Environment

Temperature: 22° C. (71.6° F.)
Humidity: 50% (+/−10%)

Procedure

Turn MTS on and start software.
Place lacrosse head 100 on MTS using custom coupling 402.
Select the “Head Flexibility Test” in the software.
Lower crosshead 222 on MTS until a pre-load of 0.5 lbf on lacrosse head 100 is reached.
Start test, with increasing force (pounds force, lbf; perpendicular to lacrosse head 100) until a 0.25″ deflection in the lacrosse head is reached.
Continue testing head and record stiffness.

Example 2: Impact Testing

The following example describes the methods used to measure the impact durability (or strength) of a lacrosse head. If a lacrosse head survives a predetermined amount of cycles (generally 300 cycles) it is considered ready for play. The test also provides competitive matrices from the data collected.

Equipment

Thor XL (custom built—see FIG. 3A)

Environment

Temperature: 22° C. (71.6° F.)
Humidity: 50% (+/−10%)

Materials And Specs

3-Phase Induction Motor (306) (IronHorse model #MTCP-001-3BD12)
Impact Arm (308) (McMaster-Carr Part #6527K364)

- Steel
- Weight—2.8 lbs. (including flange and fasteners)
- Height—1″
- Width—1″
- Length—1′

Torsion Spring (308) (McMaster-Carr Part #9271K126)

TABLE 3

Torsion Spring Characteristics

Spring Type	Torsion	Leg length		4

Defection Angle	180°	Number of Colts	9
Wind Direction	Right-Hand	Spring Length @	1.553
		Maximum Torque
OD	1.189°	Maximum Torque	42.86 in. lbs.
For Shaft Diameter	0.735°	Material	Music-Wire Steel
Wire Diameter	0.135°	RoHS	Compliant

indicates data missing or illegible when filed

AC Drive (GS2 Series Drive Model GS2-11P0)
Frequency—50 hz (Velocity at impact is 50 mph±5 mph (22.4 m/s±2.2 m/s)
Titanium Shaft (302) to hold lacrosse head
30″ radius from center axis of motor (306) and impact arm (308).

Procedure

Place a lacrosse head on shaft and screw into place.
Turn on and release the E-stop.
Press the “10 Cycle” button.
Record the # of hits.
Continue testing and observing until the lacrosse head fails (defined as a visual crack, fracture or break (320 in FIG. 3B), not a plastic deformation or elongation (322 in FIG. 3B)).
Stop test after head reaches the desired number of minimum impacts (suitably 100-300).
Record the number of impacts along with a pass/fail grade.
** Additional testing can go beyond the minimum number of impacts in order to reach failure to understand the limits of different types of heads and materials.

Results

Pass Criteria: Head survives 100 impacts (or higher, e.g., 300 impacts) without breaking for men's lacrosse head; 20 impacts or higher without breaking for women's lacrosse head.
Fail Criteria: Head breaks before 100 impacts (or lower, e.g., 40 impacts, 30 impacts, 20 impacts, depending on desired impact resistance for the men's or women's game). Heads are also taken beyond 250 impacts to determine the ultimate number of impacts that can be withstood prior to failure.
Table 4 shows the calculation of the kinetic energy of the lacrosse head prior to impact between the lacrosse head and the spring-loaded, steel impact beam. A range of linear velocities was used to provide general ranges for the kinetic energy. In addition, several different lacrosse head styles were included, with different masses, to provide a range for the kinetic energy of the lacrosse head during the impact testing. As indicated, the range of kinetic energies of the lacrosse head prior to each impact is from about 25 Joules to about 55 Joules.

TABLE 4

Kinetic Energy Calculation for Impact Testing

Test Instrument Characteristics

Shaft (302 in FIG. 3A)	0.762	m
Radius
Linear Velocity (low)	20.11677	m/s
Linear Velocity (mid)	22.35196	m/s
Linear Velocity (high)	24.58716	m/s

Kinetic Energy Calculations

					Mass
				Angular	Moment	Rotational
				Velocity	of	Kinetic
				(rad/s)	Inertia	Energy
				(ω =	(kg m²)	(Joules)
Lacrosse Head	Mass	Velocity	Radius	Velocity/	I = Mass*	KE_rot=
Design	(kg)	(m/s)	(m)	Radius)	Radius²	½* I*ω²

Rebel - O	0.139	20.117	0.762	26.400	0.0807	28.126
Rebel - O	0.139	22.35196	0.762	29.333	0.0807	34.723
Rebel - O	0.139	24.58716	0.762	32.267	0.0807	42.015
Rebel - O	0.145	20.117	0.762	26.400	0.0842	29.340
Rebel - O	0.145	22.35196	0.762	29.333	0.0842	36.222
Rebel - O	0.145	24.58716	0.762	32.267	0.0842	43.828
Rebel - O	0.156	20.117	0.762	26.400	0.0906	31.565
Rebel - O	0.156	22.35196	0.762	29.333	0.0906	38.970
Rebel - O	0.156	24.58716	0.762	32.267	0.0906	47.153
Rebel - O	0.159	20.117	0.762	26.400	0.0923	32.172
Rebel - O	0.159	22.35196	0.762	29.333	0.0923	39.719
Rebel - O	0.159	24.58716	0.762	32.267	0.0923	48.060
Rebel - O	0.156	20.117	0.762	26.400	0.0906	31.565
Rebel - O	0.156	22.35196	0.762	29.333	0.0906	38.970
Rebel - O	0.156	24.58716	0.762	32.267	0.0906	47.153
Rebel - O	0.153	20.117	0.762	26.400	0.0888	30.958
Rebel - O	0.153	22.35196	0.762	29.333	0.0888	38.220
Rebel - O	0.153	24.58716	0.762	32.267	0.0888	46.246
Mirage	0.131	20.117	0.762	26.400	0.0761	26.507
Mirage	0.131	22.35196	0.762	29.333	0.0761	32.724
Mirage	0.131	24.58716	0.762	32.267	0.0761	39.597
Mirage	0.147	20.117	0.762	26.400	0.0854	29.744
Mirage	0.147	22.35196	0.762	29.333	0.0854	36.721
Mirage	0.147	24.58716	0.762	32.267	0.0854	44.433
Mirage	0.147	20.117	0.762	26.400	0.0854	29.744
Mirage	0.147	22.35196	0.762	29.333	0.0854	36.721
Mirage	0.147	24.58716	0.762	32.267	0.0854	44.433
Rebel - D	0.174	20.117	0.762	26.400	0.1010	35.208
Rebel - D	0.174	22.35196	0.762	29.333	0.1010	43.466
Rebel - D	0.174	24.58716	0.762	32.267	0.1010	52.594
Rebel - D	0.174	20.117	0.762	26.400	0.1010	35.208
Rebel - D	0.174	22.35196	0.762	29.333	0.1010	43.466
Rebel - D	0.174	24.58716	0.762	32.267	0.1010	52.594

Example 3: Development and Testing of Clear and Translucent Lacrosse Heads

Background

Prior attempts to create clear lacrosse heads focused on using several thermoplastics, including polycarbonate, thermoplastic polyurethane (TPU) and amorphous polyamides. The resulting heads were not acceptable for the following reasons:

- Polycarbonate—Clear, but with resulting head exhibiting low durability, heavy and very stiff
- TPU—Cloudy appearance with resulting head exhibiting very low durability and high flexibility.
- Amorphous Polyamide—Clear with very yellow tint, resulting head exhibiting low durability, high stiffness and difficult to process.

The issues to overcome, included balancing minimum durability requirements versus optical clarity. However, an increase in impact modifier to boost durability, can have a detrimental effect on optical clarity and stiffness.

Impact Modified Nylon

A transition to impact modified nylon resulted in the desired optical clarity characteristics, while also achieving the needed material characteristics for optimal playability.
Manufacturing of the lacrosse heads with the impact modified nylon utilized “packing out” (pushing more plastic into the part) to the maximum extent possible, to optimize the desired mechanical characteristics. Parts that are more packed are heavy, which is often not desired, and can cause flash (sharp plastic) on the part surface. It can also be very hard on the injection molding press. Packing of the parts to the maximum extent possible, well beyond the calculated weight, was carried out. The increased pack out pressure acts to increase the strength of knit lines. Knit lines are created when plastic flows around geometric features in parts. Knit line strength is very critical to durability.
As shown in the Table 5 below, the clear lacrosse head part weights were >4-7% heavier than the calculated weight (due to packing out), and achieved the durability desired for play. This extra pack out minimizes the benefits of the lower specific gravity of the impact modified nylon material in exchange for durability. It was surprising and unexpected that use of packing out resulted in the desired playability characteristics, while still maintaining a manageable weight and the optical clarity of the lacrosse head.

TABLE 5

Calculated weight versus Actual weights of Impact Modified Nylon (IMN)

				Impact		IMN		% diff. in
				modified		Weight		IMN
Lacrosse		Material		nylon	%	(calc.	IMN	weight
Head	Production	Specific	Production	specific	difference	by %	Weight	(Actual
Geometry	Material	Gravity	Weight (g)	gravity	in S.G.	diff.)	(Actual)	vs Calc.)

DNA	PolySource	1.24	170.7 g	1.00	80.65%	137.67 g	146.5 g	106.41%
	Integra 9060
	(Polyketone)
Mirage 2	RTP 200H	1.08	141.5 g	1.00	92.59%	131.01 g	140 g	106.86%
	(Impact
	modified
	Nylon 6)
Infinity	RTP 200H	1.08	128.1 g	1.00	92.59%	118.61 g	123.5 g	104.12%
	(Impact
	modified
	Nylon 6)

Performance Results

DNA Lacrosse Head Geometry

DNA lacrosse head geometry trials utilizing the impact modified nylon demonstrated the desired mechanical characteristics for a playable lacrosse head. See FIGS. 5A-5C. As shown, without packing out the lacrosse head with the impact modified nylon (see DNA Head), the lacrosse head had a weight of about 140 g, and a stiffness of about 26 lbf at 72° F., but failed the impact test, breaking at the back strut after 240 impacts. Packing out the lacrosse head with the impact modified nylon (see DNA Diamond) resulted in a lacrosse head that was able to withstand an acceptable 290 hits without breaking, and have a weight of about 146.5 g, and a stiffness of between 27-29 lbf.

Mirage 2 Lacrosse Head Geometry

Mirage 2 lacrosse head geometry trials utilizing the impact modified nylon demonstrated the desired mechanical characteristics for a playable lacrosse head. See FIGS. 6A-6C. Packing out the lacrosse head with the impact modified nylon resulted in a lacrosse head that was able to withstand an acceptable 240 hits without breaking, and have a weight of about 140.9 g, and a stiffness of about 27.6 lbf.

Infinity Lacrosse Head Geometry

Infinity lacrosse head geometry trials (a lacrosse head for use in women's lacrosse) comprising the impact modified nylon demonstrated the desired mechanical characteristics for a playable lacrosse head. See FIGS. 7A-7C. Packing out the lacrosse head with the impact modified nylon resulted in a lacrosse head that was able to withstand an acceptable 25 hits without breaking, and have a weight of about 124.1 g, and a stiffness of about 16.2 lbf at 72° F.

Optical Clarity Results

In order to determine the level of light transmission, a Window Tint Meter which measures between 0% to 100% light transmission was utilized. Device specifications are provided above.
Utilizing this device, light transmission measurements were made through several plastic samples, including a device calibration plate (provided with unit) and clear glass. The light transmission of each material is noted in Table 6. A side by side reference photograph of the materials is provided in FIG. 8.

TABLE 6

Light Transmission Measurements

	Material	Light Transmission (%)

	Glass	95.6
	Resmart Ultra PC	84.9
	Grilamid TR RDS 4863	81.3
	Calibration Plate	18.6
	TPU	17.2

As indicated, the impact modified nylon product GRILAMID® TR RDS 4863, demonstrated a light transmission of about 81.3%.

Performance of Other Optically Clear Materials

Resmart Ultra PC, a polycarbonate material, was molded into the DNA geometry. The DNA Ultra PC provides a comparison for clarity and durability versus the DNA Diamond (GRILAMID® TR RDS 4863). The results of the DNA Ultra PC (polycarbonate) are provided in FIGS. 9A-9C. As indicated, while the polycarbonate version of the DNA exhibits higher light transmission, the playability characteristics are lower than the DNA Diamond. The weight of the DNA head using the polycarbonate material was significantly higher (about 169 g) than the impact modified nylon, an undesirable characteristic. In addition, the polycarbonate material resulted in a much higher stiffness (41.7 lbf), and was only able to withstand 50 impact hits prior to failure. These characteristics are not acceptable for a lacrosse head for use in men's lacrosse. See FIGS. 5A-5C for mechanical characteristics of the DNA Diamond head comprising impact modified nylon.
The Ultra PC polycarbonate material was also used to prepare an Infinity lacrosse head, to explore its characteristics as a lacrosse head for use in women's lacrosse. As shown in FIGS. 10A-10C, while the lacrosse head did have a higher light transmission, it had significantly greater weight (147.9 g), much higher stiffness (27 lbf), and failed after less than 10 impacts (very low durability). All of these characteristics are not optimal for use in a head for women's lacrosse, in contrast to the characteristics observed with the impact modified nylon of the Diamond lacrosse head (see FIGS. 7A-7C)
In summary, these results demonstrate the surprising and unexpected mechanical properties of the optically clear lacrosse heads described herein.
The breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the appended claims and their equivalents. It will also be understood that each feature of each embodiment discussed herein, and of each reference cited herein, can be used in combination with the features of any other embodiment. All patents and publications discussed herein are incorporated by reference herein in their entirety.

Claims

What is claimed is:

1. A lacrosse head comprising:

opposing sidewalls joined at one end by a throat, the sidewalls diverging generally outwardly, and the sidewall being connected at another end by a scoop,

wherein the lacrosse head comprises a nylon polymer that exhibits greater than 60% light transmission.

2. The lacrosse head of claim 1, wherein the nylon polymer is an impact modified nylon.

3. The lacrosse head of claim 1, having a stiffness of less than 35.0 lbf when measured at a temperature between 70° F.-75° F.

4. The lacrosse head of claim 1, wherein the lacrosse head can withstand more than 250 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact.

5. The lacrosse head of claim 1, wherein the nylon polymer exhibits greater than 75% light transmission.

6. The lacrosse head of claim 1, having a weight of less than 170 g.

7. The lacrosse head of claim 1, having a stiffness of about 20 lbf to about 31 lbf when measured at a temperature between 70T-75″F, a weight of about 110 g to about 130 g, and wherein the lacrosse head can withstand more than 150 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 joules to about 55 Joules prior to each impact.

8. The lacrosse head of claim 1, having a stiffness of about 5 lbf to about 20 lbf when measured at a temperature between 70° F.-75° F., a weight of about 100 g to about 125 g, and wherein the lacrosse head can withstand more than 20 impacts prior to failure, when the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact.

9. A lacrosse head comprising:

opposing sidewalls joined at one end by a throat, the sidewall diverging generally outwardly, and the sidewalls being connected at another end by a scoop,

wherein the lacrosse head comprises a polymer that exhibits greater than 60% light transmission, and

wherein the lacrosse head has a weight of about 110 g to about 150 g, a stiffness of about 20 lbf to about 35 lbf When measured at a temperature between 70° F.-75° F., and wherein the lacrosse head can withstand more than L50 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact, or

wherein the lacrosse head has a weight of about 100 g to about 125 g, a stiffness of about 5 lbf to about 20 lbf when measured at a temperature between 70° F.-75°, and wherein the lacrosse head can withstand more than 20 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact.

10. The lacrosse head of claim 9, wherein the polymer exhibits greater than 75% light transmission.

11. The lacrosse head of claim 9, wherein the lacrosse head can withstand more than 200 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 joules prior to each impact.

12. The lacrosse head of claim 9, wherein the polymer is an impact modified nylon.

13. The lacrosse head of claim 9, wherein the lacrosse head has a weight of about 130 g to about 150 g, a stiffness of about 25 lbf to about 30 lbf when measured at a temperature between 70° F.-75° F., and wherein the lacrosse head can withstand more than 200 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact.

14. The lacrosse head of claim 9, wherein the lacrosse head has a weight of about 100 g to about 125 g, a stiffness of about 5 lbf to about 20 lbf when measured at a temperature between 70° F.-75° F., and wherein the lacrosse head can withstand more than 30 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact.

15. A lacrosse head comprising:

wherein the lacrosse head comprises a nylon polymer that exhibits about 15% to about 50% light transmission, and

wherein the lacrosse head has a weight of about 100 g to about 150 g, a stiffness of about 20 lbf to about 35 lbf when measured at a temperature between 70° F.-75° F., and wherein the lacrosse head can withstand more than 150 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact, or

16. The lacrosse head of claim 15, wherein the nylon polymer exhibits about 18% to about 30% light transmission.

17. The lacrosse head of claim 15, wherein the lacrosse head can withstand more than 200 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact.

18. The lacrosse head of claim 15, wherein the nylon polymer is an impact modified nylon.

19. The lacrosse head of claim 15, Wherein the lacrosse head has a weight of about 130 g to about 150 g, a stiffness of about 25 lbf to about 30 lbf when measured at a temperature between 70° F.-75° F., and wherein the lacrosse head can withstand more than 200 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact.

20. The lacrosse head of claim 15 wherein the lacrosse head has a weight of about 120 g to about 125 g, a stiffness of about 15 lbf to about 20 lbf when measured at a temperature between 70° F.-75° F., and wherein the lacrosse head can withstand more than 30 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact.

21. A lacrosse head comprising:

opposing sidewalls joined at one end by a throat, the sidewalls diverging generally outwardly, and the sidewalls being connected at another end by a scoop,

wherein the lacrosse head comprises an impact modified nylon 12 polymer that exhibits greater than 75% light transmission,

and wherein the lacrosse head has a weight of less than 150 g, a stiffness of less than 30.0 lbf when measured at a temperature between 70° F.-75° F., and wherein the lacrosse head can withstand more than 150 impacts prior to failure, wherein the lacrosse head has attained a kinetic energy of about 25 Joules to about 55 Joules prior to each impact.